Adiyaman A, Dechering DG, Boggia J, Li Y, Hansen TW, Kikuya M, Björklund-Bodegård K, Richart T, Thijs L, Torp-Pedersen C, Ohkubo T, Dolan E, Imai Y, Sandoya E, Ibsen H, Wang J, Lind L, O’Brien E, Thien T, Staessen JA; International Database on Ambulatory Blood Pressure Monitoring in Relation to Cardiovascular Outcomes Investigators. (Dec 2008). Determinants of the ambulatory arterial stiffness index in 7604 subjects from 6 populations.Hypertension. 52(6):1038-44.
The ambulatory arterial stiffness index (AASI) is derived from 24-hour ambulatory blood pressure recordings. We investigated whether the goodness-of-fit of the AASI regression line in individual subjects (r(2)) impacts on the association of AASI with established determinants of the relation between diastolic and systolic blood pressures. We constructed the International Database on the Ambulatory Blood Pressure in Relation to Cardiovascular Outcomes (7604 participants from 6 countries). AASI was unity minus the regression slope of diastolic on systolic blood pressure in individual 24-hour ambulatory recordings. AASI correlated positively with age and 24-hour mean arterial pressure and negatively with body height and 24-hour heart rate. The single correlation coefficients and the mutually adjusted partial regression coefficients of AASI with age, height, 24-hour mean pressure, and 24-hour heart rate increased from the lowest to the highest quartile of r(2). These findings were consistent in dippers and nondippers (night:day ratio of systolic pressure >or=0.90), women and men, and in Europeans, Asians, and South Americans. The cumulative z score for the association of AASI with these determinants of the relation between diastolic and systolic blood pressures increased curvilinearly with r(2), with most of the improvement in the association occurring above the 20th percentile of r(2) (0.36). In conclusion, a better fit of the AASI regression line enhances the statistical power of analyses involving AASI as marker of arterial stiffness. An r(2) value of 0.36 might be a threshold in sensitivity analyses to improve the stratification of cardiovascular risk.
Agarwal R, Light RP. (Nov 2008). Physical activity and hemodynamic reactivity in chronic kidney disease. Clin J Am Soc Nephrol.3(6):1660-8.
BACKGROUND AND OBJECTIVES: Patients with chronic kidney disease (CKD) have an elevated cardiovascular risk. This study was designed to understand better the presence and strength of the relationship between physical activity and BP and to explore determinants of hemodynamic reactivity. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Twenty-four patients with CKD (mean age 69.5 yr; 3.1 antihypertensive drugs; estimated GFR 47 ml/min per 1.73 m(2), albumin/creatinine ratio 403 mg/g) were studied on three occasions during a 6-wk period with 24-h ambulatory BP monitoring and simultaneous activity monitoring with wrist actigraphy. RESULTS: Nondippers were found have a greater level of sleep activity compared with dippers, although the awake activity level was similar (7.06 versus 6.73) between groups (P = 0.042 for interaction). In 3587 BP activity pairs, hemodynamic reactivity was variable between individuals (systolic BP reactivity 1.06 [SD 10.50]; diastolic BP reactivity 0.89 [SD 7.80] heart rate reactivity 1.18 [SD 11.00]); those who were more sedentary had a greater increment in systolic BP compared with those who were less sedentary. Antihypertensive drugs blunted hemodynamic reactivity. Hemodynamic reactivity was greatest between 12 a.m. and 8 a.m., making this a vulnerable period for cardiovascular events. CONCLUSIONS: Greater hemodynamic reactivity in sedentary people with CKD offers a possible and thus far unrecognized mechanism of cardiovascular damage. Besides reducing BP, antihypertensive drugs reduce hemodynamic reactivity, which offers another plausible mechanism of cardiovascular protection with their use.
Amici A, Cicconetti P, Sagrafoli C, Baratta A, Passador P, Pecci T, Tassan G, Verrusio W, Marigliano V, Cacciafesta M. (Dec 2008). Exaggerated morning blood pressure surge and cardiovascular events. A 5-year longitudinal study in normotensive and well-controlled hypertensive elderly. Arch Gerontol Geriatr. [Epub ahead of print]
Cardiovascular events (CE) occur most frequently in the morning hours in hypertensive subjects. We studied the association between the morning blood pressure (BP) surge and CE in prognosis of 10 normotensive and 32 well-controlled hypertensive elderly, in whom ambulatory BP monitoring was performed and who were followed prospectively for 5 years. The morning surge (MS) of BP was calculated as mean systolic BP during 2h after awakening-mean systolic BP during 1h that included the lowest sleep BP. During an average of 60 months, five CE occurred. When the patients were divided into two groups according to MS, those in the top terzile (MS group; MS>/=34 mmHg, n=14) had a higher prevalence of CE (5 versus 0, p=0.001) during the follow-up period, than the others (non-MS group; MS<34 mmHg, n=28). The logistic regression analysis showed the MS sleep-trough surge as predictive variable of CE (odds ratio, OR=0.794, p=0.022). In conclusion, in older normotensives and well-controlled hypertensives, a higher BP MS is associated with vascular risk independently of clinical and ambulatory BP. Reduction of the MS could thus be a therapeutic target for preventing vascular events also in non-hypertensive patients.
Anderson DE, McNeely JD, Chesney MA, Windham BG. (Dec 2008). Breathing variability at rest is positively associated with 24-h blood pressure level. Am J Hypertens. 21(12):1324-9.
BACKGROUND: Previous research has reported that inhibition of breathing can be observed in hypertensive patients at rest during the daytime, as well as in sleep at night. The present study hypothesized that the variability of breathing and end-tidal CO(2) (PetCO(2)) in seated women at rest is positively associated with their 24-h blood pressure level. METHODS: Breath-to-breath measures of breathing rate and tidal volume were recorded via inductive plethysmography in each of 54 women during two 20-min sessions of seated rest, and in 32 women during night time sleep. PetCO(2) was also recorded during these sessions via a respiratory gas monitor. Ambulatory blood pressure was recorded for 24 h between the two clinic sessions via oscillometry. RESULTS: Breath pauses >10 s were observed significantly more often in women in the upper than the lower tertile of 24-h systolic blood pressure. Breath-to-breath variability in breathing rate, tidal volume, and minute ventilation were greater in the higher blood pressure tertile women. Variability in PetCO(2) was also greater in high blood pressure tertile. These associations were independent of age, weight, and body surface area (BSA). Breathing variability was inversely correlated with heart rate variability (HRV). CONCLUSION: Greater variability in breathing at rest that is independent of metabolic activity characterizes women with elevated blood pressure. The linear association of breathing variability with 24-h blood pressure level is consistent with the hypothesis that intermittent breathing inhibition may predispose to the development of some forms of hypertension.
Axelsson J, Reinprecht F, Siennicki-Lantz A, Elmståhl S. (Oct 2008). Low ambulatory blood pressure is associated with lower cognitive function in healthy elderly men. Blood Press Monit. 13(5):269-75.
INTRODUCTION: Low blood pressure (BP) has been found to be associated with cerebrovascular damage in the elderly. Studies of the relation of ambulatory BP to cognitive function in elderly persons aged 80 years or above is lacking, however. METHODS: Ninety-seven 81-year-old men from the population study ‘Men born in 1914′ underwent ambulatory BP monitoring and were given a cognitive test battery, 79 subjects completing all six tests. Low ambulatory systolic blood pressure (SBP) was defined as <130 mmHg and low ambulatory diastolic blood pressure (DBP) as <80 mmHg (corresponding in terms of office BP to approximately <140 and <90 mmHg, respectively). Odds ratios (OR) for lower cognitive function were calculated using a forward stepwise logistic regression model, controlling for confounding factors. RESULTS: Subjects with ambulatory SBP <130 mmHg had higher OR values for daytime (OR 2.6; P=0.037), nighttime (OR 3.6; P=0.032) and 24h (OR 2.6; P=0.038) BP measurements. A lower cognitive function was associated with lower nighttime SBP and DBP levels and lower 24-h mean SBP compared to subjects with higher cognitive function. OR values connected to low nocturnal SBP, had a tendency to be particularly high among subjects on anti-hypertensive drugs (OR 9.1; P=0.067, n.s.). CONCLUSION: Ambulatory SBP levels <130 mmHg and lower nighttime SBP and DBP were associated with lower cognitive function in healthy elderly men. Further investigation is needed to ascertain the effects of the presently recommended treatment goal of <140 mmHg for office SBP also on elderly over 80 years of age.
Ayazi S, Leers JM, Oezcelik A, Abate E, Peyre CG, Hagen JA, Demeester SR, Banki F, Lipham JC, Demeester TR, Crookes PF. (Dec 2008). Measurement of gastric pH in ambulatory esophageal pH monitoring. Surg Endosc. [Epub ahead of print]
BACKGROUND: Ambulatory esophageal pH monitoring is the method used most widely to quantify gastroesophageal reflux. The degree of gastroesophageal reflux may potentially be underestimated if the resting gastric pH is high. Normal subjects and symptomatic patients undergoing 24-h pH monitoring were studied to determine whether a relationship exists between resting gastric pH and the degree of esophageal acid exposure. METHODS: Normal volunteers (n = 54) and symptomatic patients without prior gastric surgery and off medication (n = 1,582) were studied. Gastric pH was measured by advancing the pH catheter into the stomach before positioning the electrode in the esophagus. The normal range of gastric pH was defined from the normal subjects, and the patients then were classified as having either normal gastric pH or hypochlorhydria. Esophageal acid exposure was compared between the two groups. RESULTS: The normal range for gastric pH was 0.3-2.9. The median age of the 1,582 patients was 51 years, and their median gastric pH was 1.7. Abnormal esophageal acid exposure was found in 797 patients (50.3%). Hypochlorhydria (resting gastric pH >2.9) was detected in 176 patients (11%). There was an inverse relationship between gastric pH and esophageal acid exposure (r = -0.13). For the patients with positive 24-h pH test results, the major effect of gastric pH was that the hypochlorhydric patients tended to have more reflux in the supine position than those with normal gastric pH. CONCLUSION: There is an inverse, dose-dependent relationship between gastric pH and esophageal acid exposure. Negative 24-h esophageal pH test results for a patient with hypochlorhydria may prompt a search for nonacid reflux as the explanation for the patient’s symptoms.
Aziz O, Lo B, Pansiot J, Atallah L, Yang GZ, Darzi A. (Oct 2008). From computers to ubiquitous computing by 2010: health care. Philos Transact A Math Phys Eng Sci. 366(1881):3805-11.
Over the past decade, miniaturization and cost reduction in semiconductors have led to computers smaller in size than a pinhead with powerful processing abilities that are affordable enough to be disposable. Similar advances in wireless communication, sensor design and energy storage have meant that the concept of a truly pervasive ‘wireless sensor network’, used to monitor environments and objects within them, has become a reality. The need for a wireless sensor network designed specifically for human body monitoring has led to the development of wireless ‘body sensor network’ (BSN) platforms composed of tiny integrated microsensors with on-board processing and wireless data transfer capability. The ubiquitous computing abilities of BSNs offer the prospect of continuous monitoring of human health in any environment, be it home, hospital, outdoors or the workplace. This pervasive technology comes at a time when Western world health care costs have sharply risen, reflected by increasing expenditure on health care as a proportion of gross domestic product over the last 20 years. Drivers of this rise include an ageing post ‘baby boom’ population, higher incidence of chronic disease and the need for earlier diagnosis. This paper outlines the role of pervasive health care technologies in providing more efficient health care.
Baggett CD, Stevens J, McMurray RG, Evenson KR, Murray DM, Catellier DJ, He K. (Oct 2008). Tracking of Physical Activity and Inactivity in Middle School Girls. Med Sci Sports Exerc. [Epub ahead of print]
PURPOSE: The purpose of this study was to describe and compare the levels of tracking of physical activity and inactivity as assessed by self-report and accelerometry in middle school girls during a 2-yr period. METHODS: Participants (n = 951) were from the Trial of Activity for Adolescent Girls (TAAG). The TAAG intervention had minimal effect on physical activity; therefore, both intervention and control participants were included. Inactivity and physical activity were measured by accelerometry (MTI ActiGraph) and self-report (3-d physical activity recall). RESULTS: Weighted kappa statistics ranged from 0.14 to 0.17 across inactivity, moderate-to-vigorous physical activity (MVPA), and vigorous physical activity (VPA) for self-report, from 0.13 to 0.20 for 3-d accelerometry, and from 0.22 to 0.29 for a 6-d accelerometry. Intraclass correlations ranged from 0.17 to 0.22 for self-report, 0.06 to 0.23 for 3-d accelerometry, and 0.16 to 0.33 for a 6-d accelerometry. In general, the estimates from the 6-d accelerometry tended to be higher than those from self-report, whereas few differences were observed between 3-d accelerometry and self-report. Odds ratios (OR) for being in the highest quintile at eighth grade for those in the highest quintile at sixth grade compared with those in any other quintile at sixth grade were 3.26 (95% confidence interval = 2.28-4.67), 3.64 (2.55-5.20), and 3.45 (2.42-4.93) for the 6-d accelerometry-measured inactivity, MVPA, and VPA. Corresponding OR from self-report were 2.44 (1.66-3.58) for inactivity, 2.63 (1.83-3.79) for MVPA, and 2.23 (1.54-3.23) for VPA. CONCLUSION: Tracking of inactivity and physical activity in middle school girls was fair to moderate. Our results suggest that physical activity and inactivity habits are dynamic for most girls during early adolescence. Population-based efforts should be made in this age group to promote physical activity and offer alternatives to inactivity for all girls.
Balkau B, Mhamdi L, Oppert JM, Nolan J, Golay A, Porcellati F, Laakso M, Ferrannini E; EGIR-RISC Study Group. (Oct 2008). Physical activity and insulin sensitivity: the RISC study. Diabetes. 57(10):2613-8.
OBJECTIVE: Physical activity is a modifiable risk factor for type 2 diabetes, partly through its action on insulin sensitivity. We report the relation between insulin sensitivity and physical activity measured by accelerometry. RESEARCH DESIGN AND METHODS: This is a cross-sectional study of 346 men and 455 women, aged 30-60 years, without cardiovascular disease and not treated by drugs for diabetes, hypertension, dyslipidemia, or obesity. Participants were recruited in 18 clinical centers from 13 European countries. Insulin sensitivity was measured by hyperinsulinemic-euglycemic clamp. Physical activity was recorded by accelerometry for a median of 6 days. We studied the relationship of insulin sensitivity with total activity (in counts per minute), percent of time spent sedentary, percent of time in light activity, and activity intensity (whether the participant recorded some vigorous or some moderate activity). RESULTS: In both men and women, total activity was associated with insulin sensitivity (P < 0.0001). Time spent sedentary, in light activity, and activity intensity was also associated with insulin sensitivity (P < 0.0004/0.01, 0.002/0.03, and 0.02/0.004, respectively, for men/women) but lost significance once adjusted for total activity. Adjustment for confounders such as adiposity attenuated the relationship with total activity; there were no interactions with confounders. Even in the 25% most sedentary individuals, total activity was significantly associated with better insulin sensitivity (P < 0.0001). CONCLUSIONS: Accumulated daily physical activity is a major determinant of insulin sensitivity. Time spent sedentary, time spent in light-activity, and bouts of moderate or vigorous activity did not impact insulin sensitivity independently of total activity.
Banegas JR, Segura J, de la Sierra A, Gorostidi M, Rodríguez-Artalejo F, Sobrino J, de la Cruz JJ, Vinyoles E, del Rey RH, Graciani A, Ruilope LM; Spanish Society of Hypertension ABPM Registry Investigators. (Dec 2008). Gender differences in office and ambulatory control of hypertension. Am J Med. 121(12):1078-84.
BACKGROUND: Gender differences in hypertension control have not been explored fully. METHODS: We studied 15,212 white men and 13,936 white women with treated hypertension who were drawn from the Spanish Ambulatory Blood Pressure Registry. For each participant, we obtained office blood pressure (BP) (average of 2 readings) and 24-hour ambulatory BP (average of measurements performed every 20 minutes during day and night). RESULTS: Only 16.4% of women and 14.7% of men had both office (<140/90 mm Hg) and ambulatory (<130/80 mm Hg) BP controlled (P<.001). Women had a lower frequency of masked hypertension (office BP<140/90 mm Hg and ambulatory BP> or =130/80 mm Hg) than men (5.9% vs 7.9%, P<.001). Women had a higher frequency of isolated office hypertension (office BP> or =140/90 mm Hg and ambulatory BP<130/80 mm Hg) (32.5% vs 24.2%, P<.001). Although office BP control (office BP<140/90 mm Hg, regardless of ambulatory values) was similar in women and men (22.3% vs 22.6%, P=.542), ambulatory BP control (ambulatory BP<130/80 mm Hg, regardless of office values) was higher in women than in men (48.9% vs 38.9%, P<.001). After adjustment for age, number of antihypertensive drugs, hypertension duration, and risk factors, gender differences in BP control remained practically unchanged. CONCLUSION: Ambulatory BP control was higher in women than in men. This may be due to the higher frequency of isolated office hypertension in women, and it is not explained by gender differences in other important clinical characteristics.
Barclay JL, Miller BG, Dick S, Dennekamp M, Ford I, Hillis GS, Ayres JG, Seaton A. (Nov 2008). A panel study of air pollution in subjects with heart failure; negative results in treated patients. Occup Environ Med. [Epub ahead of print]
Abstract Objectives To investigate pre-clinical adverse effects of ambient particulate air pollution and nitrogen oxides in patients with heart failure. Methods A cohort of 132 non-smoking patients resident in Aberdeen, Scotland, with stable chronic heart failure were enrolled in a repeated measures panel study. Patients with atrial fibrillation or pacemakers were excluded. Participants were studied for 3 days every two months for up to a year with monitoring of pollutant exposure and concurrent measurements of patho-physiological responses. Measurements included daily area PM10, particle number concentration (PNC) and nitrogen oxides, daily estimated personal PM2.5 and PNC exposures and 3-day cumulative personal nitrogen dioxide (NO2) measurements. Concurrent meteorologic data were recorded. Blood was taken at the end of each 3-day block for assays of markers of endothelial activation, inflammation and coagulation. Cardiac rhythm was monitored by ambulatory Holter monitor during the final 24 hours of each block. Results The average 24-hour background ambient PM10 ranged from 7.4-68 microg.m-3 and PNC from 454-11,283 particles.cm-3. No associations were demonstrated between the incidence of arrhythmias, heart rate variability or haematological/biochemical measures and any variations in pollutant exposures at any lags. Conclusions Assuming that low level pollution affects the parameters measured, these findings may suggest a beneficial effect of modern cardioprotective therapy which may modify responses to external risk factors. Widespread use of such drugs in susceptible populations may in future reduce the adverse effects of air pollution on the heart.
Basterfield L, Adamson AJ, Parkinson KN, Maute U, Li PX, Reilly JJ; Gateshead Millennium Study Core Team. (Dec 2008). Surveillance of physical activity in the UK is flawed: validation of the Health Survey for England Physical Activity Questionnaire. Arch Dis Child. 93(12):1054-8.
OBJECTIVE: Public health surveillance of physical activity in children in the UK depends on a parent-reported physical activity questionnaire which has not been validated. We aimed to validate this questionnaire against measurement of physical activity using accelerometry in 6-7-year-old children. METHODS: In 130 children aged 6-7 years (64 boys, 66 girls) we estimated habitual moderate-vigorous intensity physical activity (MVPA) using the Health Survey for England parent-report questionnaire for physical activity. For the same time period and the same children, we measured MVPA objectively using 7-day accelerometry with the Actigraph accelerometer. RESULTS: The questionnaire over-estimated MVPA significantly (paired t test, p<0.01). Mean error (bias) when using the questionnaire was 122 min/day (95% CI 124 to 169). Mean time spent in MVPA was 146 min/day (95% CI 124 to 169) using the questionnaire and 24 min/day (95% CI 22 to 26) using the accelerometer. Rank order correlations between MVPA measured by accelerometer and estimated by the questionnaire were not statistically significant. CONCLUSIONS: Public health surveillance of physical activity should not rely on this questionnaire. Levels of habitual physical activity in children are likely to be substantially lower than those reported in UK health surveys.
Biddle SJ, Gorely T, Marshall SJ, Cameron N. (Nov 2008). The prevalence of sedentary behavior and physical activity in leisure time: A study of Scottish adolescents using ecological momentary assessment. Prev Med. [Epub ahead of print]
OBJECTIVE: To report time and prevalence of leisure time sedentary and active behaviors in adolescents. METHOD: Cross-sectional, stratified, random sample from schools in 14 districts in Scotland, 2002-03, using ecological momentary assessment (n=385 boys, 606 girls; mean age 14.1 years; range 12.6-16.7 years). This is a method of capturing current behavioral episodes. We used 15 min time intervals. RESULTS: Television viewing occupied the most leisure time. The five most time consuming sedentary activities occupied 228 min per weekday and 396 min per weekend day for boys, and 244 min per weekday and 400 min per weekend day for girls, with TV occupying one-third to one-half of this time. In contrast, 62 min was occupied by active transport and sports/exercise per weekday and 91 min per weekend day for boys, with 55 min per weekday and 47 min per weekend day for girls. A minority watched more than 4 h of TV per day, with more at weekends. Other main sedentary behaviors for boys were homework, playing computer/video games, and motorised transport and, for girls, homework, motorised transport, and sitting and talking. CONCLUSION: Scottish adolescents engage in a variety of sedentary and active behaviors. Research into sedentary behavior must assess multiple behaviors and not rely solely on TV viewing.
Binder S, Deuschl G, Volkmann J (Dec 2008). Effect of Cabergoline on Parkinsonian Tremor Assessed by Long-Term Actigraphy. Eur Neurol. 18;61(3):149-153.
Background: Tremor is one of the cardinal symptoms in Parkinson’s disease, but only few clinical studies have focussed on its therapy as the primary endpoint. One reason is the substantial fluctuation of tremor severity over time, which is difficult to capture and may render momentary clinical assessments unreliable. Methods: We evaluated the usefulness of a novel wrist-worn actigraph allowing long-term recordings of tremor in a pilot study, in which we assessed the therapeutic effect of cabergoline on tremor in 10 patients with tremor-dominant Parkinson’s disease. Clinical data were obtained by using the Unified Parkinson’s Disease Rating Scale (UPDRS Part III, item 20) and simultaneously a patient’s tremor diary. Results: We found a significant reduction in UPDRS motor and tremor scores, in tremor duration and tremor amplitude by actigraphy and diaries. Furthermore, we found significant correlations between actigraphy measurements and patient ratings of tremor intensity and occurrence in diaries. Conclusion: Long-term actigraphy is a reliable method to assess tremor occurrence and severity and may be used to document antitremor effects in clinical studies.
Boon RM, Hamlin MJ, Steel GD, Ross JJ. (Nov 2008). Validation of the New Zealand Physical Activity Questionnaire (NZPAQ-LF) and the International Physical Activity Questionnaire (IPAQ-LF) with Accelerometry. Br J Sports Med. [Epub ahead of print]
BACKGROUND: Validation of instruments used to measure physical activity patterns are essential when attempting to assess the effectiveness of physical activity interventions. OBJECTIVES: To assess the validity of two self-report physical activity questionnaires on a representative sample of New Zealand adults. METHODS: Seventy adults aged 18-65 years from around Christchurch, New Zealand were required to wear an ActiGraph GT1M accelerometer during all waking hours for seven consecutive days. Immediately following the 7-day accelerometer period participants were required to complete the long forms of both the New Zealand Physical Activity Questionnaire (NZPAQ-LF) and the International Physical Activity Questionnaire (IPAQ-LF). RESULTS: Both the NZPAQ-LF and the IPAQ-LF questionnaires showed small to moderate correlations to Actigraph data for time spent in moderate-intensity physical activity (r = 0.19 – 0.30), and total physical activity (sum of moderate and vigorous-intensity physical activity r = 0.30 – 0.32). Compared to the Actigraph data both self-report questionnaires tended to overestimate activity levels by ~ 165%. Total physical activity levels gathered from both questionnaires were strongly correlated to each other (r = 0.79) and showed good levels of agreement in the Bland-Altman plots. CONCLUSIONS: We found the long forms of the NZPAQ and IPAQ had acceptable validity when detecting participant’s ability to meet activity guidelines based on exercise duration, but a significant amount of over-estimation was evident. This presents a need for both instruments to be further developed and tested in order to increase validity.
Borriello G. (Oct 2008). Invisible computing: automatically using the many bits of data we create. Philos Transact A Math Phys Eng Sci. 366(1881):3669-83.
As we go about our work and our daily lives, we leave a trail of bits behind. Every electronic device we interact with can keep a record of our actions. Even the devices themselves can keep track of their location and radio interactions, even without user involvement. The challenge of invisible computing is to make this wealth of data useful. This paper presents two examples of what has come to be known as ‘invisible computing’, namely, devices recording, distilling and rendering these many bits of data without unduly taxing human users. The first example is focused on a work environment. Labscape automates the record keeping required of experimenters in a cell biology laboratory. The second example looks at more ad hoc interactions. RFID Ecosystem is a collection of radio-frequency identification (RFID) readers and databases that collect the sightings of passive RFID tags, attached to people and objects, as they move throughout a large building. It provides services such as people and object finding as well as diary keeping.
Boschen, Mark J.; Casey, Leanne M. (Oct 2008). The use of mobile telephones as adjuncts to cognitive behavioral psychotherapy. Professional Psychology: Research and Practice, Vol 39(5), pp. 546-552.
Despite the rapid proliferation of technological adjuncts in cognitive behavior therapy (CBT), much of this development appears to have occurred on an ad hoc basis and in many cases has resulted in applications that are beyond the resources of most practicing clinicians. The authors delineate the specific areas in which CBT can be augmented through use of technology and outline the characteristics of an ideal therapy augmentor. Mobile telephones are identified as a low-cost and accessible device whose use has been largely untapped to date. The existing literature on use of the mobile phone is reviewed, and potential areas for its application in CBT are examined. The authors conclude with clinical guidelines for its use and the recommendation that use of mobile phones in CBT is a promising avenue for both clinical practice and research.
Bouhanick B, Bongard V, Amar J, Bousquel S, Chamontin B. (Dec 2008). Prognostic value of nocturnal blood pressure and reverse-dipping status on the occurrence of cardiovascular events in hypertensive diabetic patients. Diabetes Metab. 34(6):560-7.
AIM: To assess whether reverse-dipping status is associated with cardiovascular (CV) events such as CV death, myocardial infarction (MI) or stroke in diabetic patients with hypertension. METHODS: A total of 97 diabetic patients underwent their first ambulatory blood pressure monitoring (ABPM 1). “Reverse dippers” were defined as patients with a nighttime systolic and/or diastolic blood pressure (BP) greater than daytime systolic and/or diastolic BP. Other patients were called “others”. A second ABPM (ABPM 2) was done after a median delay of 2.6 years. Patients were then followed for a further 2.9-year median period (total median follow-up: 5.5 years). RESULTS: After ABPM 1, CV events occurred in 53% of the reverse dippers (n=15) and in 29% of the others (n=82). Kaplan-Meier curves showed significant differences between the two groups (P=0.003). Mean nighttime systolic BP on ABPM 1 was 148+/-23mmHg and 142+/-19mmHg in patients who did and did not experience a CV event, respectively. With Cox analysis adjusted for confounders, a 10 mmHg increase in nighttime systolic BP was associated with a 35% increase in the risk of a CV event (hazard ratio [HR]: 1.35, P=0.003). The HR for a CV event in reverse- versus nonreverse-dipping status was 2.79 (P=0.023). After ABPM 2, the relationship between the reverse-dipping status and occurrence of CV events was no longer evident (P=0.678). Nighttime systolic BP remained predictive of CV events (P=0.001). CONCLUSION: These findings suggest that nighttime systolic BP per se appeared to be a stronger predictor of an excess risk of CV events compared with reverse-dipping status.
Buffart LM, van den Berg-Emons RJ, Burdorf A, Janssen WG, Stam HJ, Roebroeck ME. (Nov 2008). Cardiovascular disease risk factors and the relationships with physical activity, aerobic fitness, and body fat in adolescents and young adults with myelomeningocele. Arch Phys Med Rehabil. 89(11):2167-73.
OBJECTIVES: To describe cardiovascular disease (CVD) risk factors in adolescents and young adults with myelomeningocele (MMC) and to explore relationships with physical activity, aerobic fitness, and body fat. DESIGN: Cross-sectional study. SETTING: Outpatient clinic. PARTICIPANTS: Adolescents and young adults (N=31) with MMC (58% men) age 16 through 30 years; 13 were ambulatory and 18 were nonambulatory. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: We studied biologic and lifestyle-related CVD risk factors, including lipid and lipoprotein profiles, blood pressure, aerobic fitness (Vo(2)peak), body fat, daily physical activity, and smoking behavior. We considered subjects at increased CVD risk when 2 or more of the following risk factors clustered: systolic blood pressure, total serum cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and cigarette smoking. Relationships were studied using regression analyses. RESULTS: Levels of TC, low-density lipoprotein cholesterol, and triglycerides were elevated in 29%, 38%, and 3% of the participants, respectively. HDL-C was reduced in 19%. Hypertension was found in 20%, and 19% were current cigarette smokers. Based on the clustering of risk factors, 42% of the participants were at increased CVD risk: 15% of ambulatory participants and 61% of nonambulatory participants (P=.03). Adjusted for sex and ambulatory status, participants with higher aerobic fitness tended to be more likely to have no CVD risk (odds ratio=13.0; P=.07). CVD risk was not associated to physical activity and body fat. CONCLUSIONS: A large proportion of the study sample was at CVD risk, indicated by clustering of risk factors. Improving aerobic fitness in young adults with MMC may contribute in reducing CVD risk; this needs to be confirmed in future studies.
Burd C, Mitchell JE, Crosby RD, Engel SG, Wonderlich SA, Lystad C, Le Grange D, Peterson CB, Crow S. (Nov 2008). An assessment of daily food intake in participants with anorexia nervosa in the natural environment. Int J Eat Disord. [Epub ahead of print]
OBJECTIVE:: To examine the caloric intake in women with anorexia nervosa (AN) and how it varies by day as a function of the presence or absence of binge eating and/or purging behaviors. METHOD:: Female participants with AN (n = 84, mean age = 24.4, range 18-51) were recruited from three different sites. Data on food intake were obtained through the use of 24-h dietary recall using the Nutritional Data Systems for Research, and data on binge eating and purging behaviors were collected on palmtop computers using an ecological momentary assessment paradigm. Daily macronutrient intake was compared on days during which binge eating and/or purging behaviors did or did not occur. RESULTS: On days during which binge eating and purging behaviors both occurred, participants reported significantly greater kilocalorie intake when compared with days when neither behavior occurred, or when only binge eating or purging occurred. Binge eating episodes were only modest in size on days when purging did not occur. Energy intake overall was higher than expected. CONCLUSION:: Intake on days where binge eating occurred varied dramatically based on whether or not purging occurred. Whether markedly increased binge eating intake was causally related to purging is unclear. Nonetheless eating episodes were at times quite large and equivalent to those reported by participants with bulimia nervosa in other research.
Chuang KJ, Coull BA, Zanobetti A, Suh H, Schwartz J, Stone PH, Litonjua A, Speizer FE, Gold DR. (2008). Particulate air pollution as a risk factor for ST-segment depression in patients with coronary artery disease. Circulation. 118(13):1314-20.
BACKGROUND: The association of particulate matter (PM) with cardiovascular morbidity and mortality is well documented. PM-induced ischemia is considered a potential mechanism linking PM to adverse cardiovascular outcomes. METHODS AND RESULTS: In a repeated-measures study including 5979 observations on 48 patients 43 to 75 years of age, we investigated associations of ambient pollution with ST-segment level changes averaged over half-hour periods measured in the modified V(5) position by 24-hour Holter ECG monitoring. Each patient was observed up to 4 times within 1 year after a percutaneous intervention for myocardial infarction, acute coronary syndrome without infarction, or stable coronary artery disease without acute coronary syndrome. Elevation in fine particles (PM(2.5)) and black carbon levels predicted depression of half-hour-averaged ST-segment levels. An interquartile increase in the previous 24-hour mean black carbon level was associated with a 1.50-fold increased risk of ST-segment depression > or =0.1 mm (95% CI, 1.19 to 1.89) and a -0.031-mm (95% CI, -0.042 to -0.019) decrease in half-hour-averaged ST-segment level (continuous outcome). Effects were greatest within the first month after hospitalization and for patients with myocardial infarction during hospitalization or with diabetes. CONCLUSIONS: ST-segment depression is associated with increased exposure to PM(2.5) and black carbon in cardiac patients. The risk of pollution-associated ST-segment depression may be greatest in those with myocardial injury in the first month after the cardiac event.
Ciolac EG, Guimarães GV, D’Avila VM, Bortolotto LA, Doria EL, Bocchi EA. (Dec 2008). Acute aerobic exercise reduces 24-h ambulatory blood pressure levels in long-term-treated hypertensive patients. Clinics. 63(6):753-8.
BACKGROUND: Even with anti-hypertensive therapy, it is difficult to maintain optimal systemic blood pressure values in hypertensive patients. Exercise may reduce blood pressure in untreated hypertensive, but its effect when combined with long-term anti-hypertensive therapy remains unclear. Our purpose was to evaluate the acute effects of a single session of aerobic exercise on the blood pressure of long-term-treated hypertensive patients. METHODS: Fifty treated hypertensive patients (18/32 male/female; 46.5+/-8.2 years; Body mass index: 27.8+/-4.7 kg/m(2)) were monitored for 24 h with respect to ambulatory (A) blood pressure after an aerobic exercise session (post-exercise) and a control period (control) in random order. Aerobic exercise consisted of 40 minutes on a cycle-ergometer, with the mean exercise intensity at 60% of the patient’s reserve heart rate. RESULTS: Post-exercise ambulatory blood pressure was reduced for 24 h systolic (126+/-8.6 vs. 123.1+/-8.7 mmHg, p=0.004) and diastolic blood pressure (81.9+/-8 vs. 79.8+/-8.5 mmHg, p=0.004), daytime diastolic blood pressure (85.5+/-8.5 vs. 83.9+/-8.8 mmHg, p=0.04), and nighttime S (116.8+/-9.9 vs. 112.5+/-9.2 mmHg, p<0.001) and diastolic blood pressure (73.5+/-8.8 vs. 70.1+/-8.4 mmHg, p<0.001). Post-exercise daytime systolic blood pressure also tended to be reduced (129.8+/-9.3 vs. 127.8+/-9.4 mmHg, p=0.06). These post-exercise decreases in ambulatory blood pressure increased the percentage of patients displaying normal 24h systolic blood pressure (58% vs. 76%, p=0.007), daytime systolic blood pressure (68% vs. 82%, p=0.02), and nighttime diastolic blood pressure (56% vs. 72%, p=0.02). Nighttime systolic blood pressure also tended to increase (58% vs. 80%, p=0.058). CONCLUSION: A single bout of aerobic exercise reduced 24h ambulatory blood pressure levels in long-term-treated hypertensive patients and increased the percentage of patients reaching normal ambulatory blood pressure values. These effects suggest that aerobic exercise may have a potential role in blood pressure management of long-term-treated hypertensive.
Cleland V, Crawford D, Baur LA, Hume C, Timperio A, Salmon J. (Nov 2008). A prospective examination of children’s time spent outdoors, objectively measured physical activity and overweight. Int J Obes (Lond) . 32(11):1685-93.
OBJECTIVE: This study aimed to determine whether time spent outdoors was associated with objectively measured physical activity, body mass index (BMI) z-score and overweight in elementary-school aged children, cross-sectionally and prospectively over 3 years. METHODS: Three-year cohort study with data collected during 2001 and 2004. Nineteen randomly selected state elementary schools across Melbourne, Australia. One hundred and eighty eight 5-6-year-old and 360 10-12-year-old children. Baseline parent reports of children’s time spent outdoors during warmer and cooler months, on weekdays and weekends. At baseline and follow-up, children’s moderate and vigorous physical activity (MVPA) was objectively assessed by accelerometry, and BMI z-score and overweight was calculated from measured height and weight. RESULTS: Cross-sectionally, each additional hour outdoors on weekdays and weekend days during the cooler months was associated with an extra 27 min week(-1) MVPA among older girls, and with an extra 20 min week(-1) MVPA among older boys. Longitudinally, more time outdoors on weekends predicted higher MVPA on weekends among older girls and boys (5 min week(-1)). The prevalence of overweight among older children at follow-up was 27-41% lower among those spending more time outdoors at baseline. CONCLUSION: Encouraging 10-12-year-old children to spend more time outdoors may be an effective strategy for increasing physical activity and preventing increases in overweight and obesity. Intervention research investigating the effect of increasing time outdoors on children’s physical activity and overweight is warranted.
Cohen, Lawrence H.; Gunthert, Kathleen C.; Butler, Andrew C.; Parrish, Brendt P.; Wenze, Susan J.; Beck, Judith S. (Dec 2008). Negative affective spillover from daily events predicts early response to cognitive therapy for depression. Journal of Consulting and Clinical Psychology, Vol 76(6), pp. 955-965.
This study evaluated the predictive role of depressed outpatients’ (N = 62) affective reactivity to daily stressors in their rates of improvement in cognitive therapy (CT). For 1 week before treatment, patients completed nightly electronic diaries that assessed daily stressors and negative affect (NA). The authors used multilevel modeling to compute each patient’s within-day relationship between daily stressors and daily NA (within-day reactivity), as well as the relationship between daily stressors and next-day NA (next-day reactivity; affective spillover). In growth model analyses, the authors evaluated the predictive role of patients’ NA reactivity in their early (Sessions 1-4) and late (Sessions 5-12) response to CT. Within-day NA reactivity did not predict early or late response to CT. However, next-day reactivity predicted early response to CT, such that patients who had greater NA spillover in response to negative events had a slower rate of symptom change during the first 4 sessions. Affective spillover did not influence later response to CT. The findings suggest that depressed patients who have difficulty bouncing back the next day from their NA reactions to a relative increase in daily negative events will respond less quickly to the early sessions of CT.
Coley B, Jolles BM, Farron A, Aminian K. (Nov 2008). Arm position during daily activity. Gait Posture. 28(4):581-7.
A new method of evaluation for functional assessment of the shoulder during daily activity is presented. An ambulatory system using inertial sensors attached on the humerus was used to detect the ability to work at a specific position of the shoulder. Nine arm positions were defined based on humerus elevation. The method was tested on 31 healthy volunteer subjects. First, we estimated the ability of the system to detect the different elevation angles and arm positions of each subject. Following that, we evaluated their arm positions during approximately 8h of daily activities. Each arm position was recognized with a good sensitivity (range 80-100%) and specificity (range 96-99%). During daily activity, we estimated the frequency (number/h) that the humerus reached each arm position during the periods of 0-1s (period P1), 1-5s (period P2) and 5-30s (period P3). Our data showed that all subjects had 96% of their arm position reached under the 5th level (100-120 degrees ). No significant difference was observed between dominant and non-dominant sides for the frequency and duration of arm positions (p>0.3). Our evaluation was in accordance with the clinical questionnaire (the Constant score) for the P1 duration, but differed for longer periods P2 and P3. By quantifying the arm positions and their durations for both shoulders, we proposed a new score to evaluate the ability to work at a specific level based on the symmetry index of the arms activity. Using this score, we obtained, on average, good symmetry for healthy subjects. This score can be useful in evaluating the asymmetry in arm function in patients with a shoulder disease. The proposed technique could be used in a number of shoulder diseases where problems in performing daily activities should be expressed in terms of objective measure of arm position.
Collop NA. (Nov 2008). Portable monitoring for the diagnosis of obstructive sleep apnea. Curr Opin Pulm Med. 14(6):525-9.
PURPOSE OF REVIEW: The demand for expedient diagnosis of suspected obstructive sleep apnea (OSA) has increased due to improved awareness of sleep disorders. Polysomnography (PSG) is the current preferred diagnostic modality but is relatively inconvenient, expensive and inefficient. Portable monitoring has been developed and is widely used in countries outside the United States as an alternative approach. A portable monitor records fewer physiologic variables but is typically unattended and can be performed in the home. RECENT FINDINGS: Numerous portable monitor studies have been performed over the past two to three decades. The US government and medical societies have extensively reviewed this literature several times in an attempt to determine if portable monitoring should be more broadly used for diagnosing OSA. In March 2008, the US Centers for Medicare and Medicaid Services released a statement allowing the use of portable monitoring to diagnose OSA and prescribe continuous positive airway pressure. This has potentially opened the door for more widespread use of these devices. This review will focus on the literature that has examined portable monitoring as a diagnostic tool for OSA. SUMMARY: It is anticipated that portable monitoring as a diagnostic modality for OSA will be used more frequently in the United States following the Centers for Medicare and Medicaid Services ruling. Physicians and others considering the use of portable monitors should thoroughly understand the advantages and limitations of this technology.
Cuddy JS, Ham JA, Harger SG, Slivka DR, Ruby BC. (Fall 2008). Effects of an electrolyte additive on hydration and drinking behavior during wildfire suppression. Wilderness Environ Med. 19(3):172-80.
OBJECTIVE: The purpose of this study was to compare the effects of a water + electrolyte solution versus plain water on changes in drinking behaviors, hydration status, and body temperatures during wildfire suppression. METHODS: Eight participants consumed plain water, and eight participants consumed water plus an electrolyte additive during 15 hours of wildfire suppression. Participants wore a specially outfitted backpack hydration system equipped with a digital flow meter system affixed inline to measure drinking characteristics (drinking frequency and volume). Body weight and urine-specific gravity were collected pre- and postshift. Ambient, core, and skin temperatures were measured continuously using a wireless system. Work output was monitored using accelerometry. RESULTS: There were no differences between groups for body weight, drinking frequency, temperature data, activity, or urine-specific gravity (1.019 +/- 0.007 to 1.023 +/- 0.010 vs. 1.019 +/- 0.005 to 1.024 +/- 0.009 for water and water + electrolyte groups pre- and postshift, respectively; P < .05). There was a main effect for time for body weight, demonstrating an overall decrease (78.1 +/- 13.3 and 77.3 +/- 13.3 kg pre- and postshift, respectively; P < .05) across the work shift. The water group consumed more total fluid (main effect for treatment) than the water + electrolyte group (504 +/- 472 vs. 285 +/- 279 mL.h(-1) for the water and water + electrolyte groups, respectively; P < .05). CONCLUSION: The addition of an electrolyte mixture to plain water decreased the overall fluid consumption of the water + electrolyte group by 220 mL.h(-1) (3.3 L.d(-1)). Supplementing water with electrolytes can reduce the amount of fluid necessary to consume and transport during extended activity. This can minimize carrying excessive weight, possibly reducing fatigue during extended exercise.
Cuspidi C, Meani S, Valerio C, Negri F, Sala C, Maisaidi M, Giudici V, Zanchetti A, Mancia G. (Dec 2008). Body mass index, nocturnal fall in blood pressure and organ damage in untreated essential hypertensive patients. Blood Press Monit. 13(6):318-24.
AIM: We sought to investigate the relationship between body mass index (BMI) and parameters derived from 48-h ambulatory blood pressure monitoring (ABPM) as well as organ damage in human hypertension. METHODS: A total of 658 consecutive outpatients with grade 1 and 2 hypertension, never treated with antihypertensive medications underwent the following procedures: (i) routine examination, (ii) 24-h urine collection for microalbuminuria, (iii) ABPM over two 24-h periods within 4 weeks, (iv) echocardiography and (v) carotid ultrasonography. Each patient was classified as lean (BMI<25 kg/m2) or overweight/obese (> or =25 kg/m2) and according to the consistency of the dipping or nondipping status in the first and second ABPM period, as dipper (DD), nondipper and variable dipper. RESULTS: Mean 48-h, daytime and nighttime systolic BP or diastolic BP were superimposable in the lean (n=314) and overweight (n=344) group. Overweight patients had a reduced nocturnal BP drop compared with their lean counterparts; the prevalence of DD pattern, indeed, was 15% lower in the overweight group as a whole, with a 17% difference in men and 13% in women. The prevalence of left ventricular hypertrophy was higher in overweight than in lean patients (31.8 vs. 15.9% in men and 48.7 vs. 15.6% in women, P<0.01); this more pronounced cardiac involvement was associated with structural carotid alterations. CONCLUSION: This study, the first to investigate the relationship between BMI and nocturnal BP patterns as assessed by two ABPM sessions, shows that overweight hypertensive patients are more likely to have a reduced nocturnal fall in BP and a greater cardiac and extracardiac organ damage as compared with their lean counterparts despite a similar overall BP load.
de Bruin ED, Hartmann A, Uebelhart D, Murer K, Zijlstra W. (Oct-Nov 2008). Wearable systems for monitoring mobility-related activities in older people: a systematic review. Clin Rehabil. 22(10-11):878-95.
OBJECTIVE: The use of wearable motion-sensing technology offers important advantages over conventional methods for obtaining measures of physical activity and/or physical functioning in aged individuals. This review aims to identify the actual state of applying wearable systems for monitoring mobility-related activity in older populations. In this review we focus on technologies and applications, research designs, feasibility and adherence aspects, and clinical relevance of wearable motion-sensing technology. DATA SOURCES: PubMed (MEDLINE since 1990), Ovid (BIOSIS, CINAHL), and Cochrane (Central) and reference lists of all relevant articles were searched. REVIEW METHODS: Two authors independently reviewed randomized and non-randomized trials on people above 65 years systematically. Quality of selected articles was scored and study results were summarised and discussed. RESULTS: Two hundred and twenty-seven abstracts were considered. After application of inclusion criteria and full text reading, 42 articles were taken into account in a full text review. Twenty of these papers evaluated walking with step counters, other papers used varying accelerometry approaches for obtaining overall activity measures (n = 16), or for monitoring changes in body postures and activity patterns (n = 17). Seven studies explicitly mentioned feasibility and/or adherence aspects. Eight studies presented outcome evaluations of interventions. Eight articles were representing descriptive research designs, three articles were using mixed descriptive and exploratory research designs, 23 articles used exploratory research-type designs, and eight articles used experimental research designs. CONCLUSION: Although feasible methods for monitoring human mobility are available, evidence-based clinical applications of these methods in older populations are in need of further development.
De Jongste JC, Carraro S, Hop WC, Baraldi E. (Oct 2008). Daily Telemonitoring of Exhaled Nitric Oxide and Symptoms in the Treatment of Childhood Asthma. Am J Respir Crit Care Med. [Epub ahead of print]
RATIONALE: Asthma treatment might improve when inhaled steroids are titrated on airway inflammation. Fractional exhaled nitric oxide (FeNO0.05), a marker of eosinophilic airway inflammation, can be measured at home. OBJECTIVES: We assessed daily FeNO0.05 telemonitoring in the management of childhood asthma. METHODS: Children with atopic asthma (n = 151) were randomly assigned to two groups: FeNO0.05 plus symptom monitoring, or monitoring of symptoms only. All patients scored asthma symptoms in an electronic diary over 30 weeks; 77 received a portable nitric oxide (NO) analyzer. Data were transmitted daily to the coordinating centers. Patients were phoned every 3 weeks and their steroid dose was adapted according to FeNO0.05 and symptoms, or according to symptoms. Children were seen at 3, 12, 21, and 30 weeks for examination and lung function testing. The primary end point was the proportion of symptom-free days in the last 12 study weeks. MEASUREMENTS AND MAIN RESULTS: Telemonitoring was feasible with reliable FeNO0.05 data for 86% of days, and valid diary entries for 79% of days. Both groups showed an increase in symptom-free days, improvement of FEV1 and quality of life, and a reduction in steroid dose. None of the changes from baseline differed between groups. The difference in symptom-free days over the last 12 weeks was 0.3% (P = 0.95; 95% confidence interval, -10 to 11%). There was a trend for fewer exacerbations in the FeNO0.05 group. CONCLUSIONS: Thirty weeks of daily FeNO0.05 and symptom telemonitoring was associated with improved asthma control and a lower steroid dose. We found no added value of daily FeNO0.05 monitoring compared with daily symptom monitoring only.
Dechering DG, van der Steen MS, Adiyaman A, Thijs L, Deinum J, Li Y, Dolan E, Akkermans RP, Richart T, Hansen TW, Kikuya M, Wang J, O’brien E, Thien T, Staessen JA. (Oct 2008). Reproducibility of the ambulatory arterial stiffness index in hypertensive patients. J Hypertens. 26(10):1993-2000.
BACKGROUND: We studied the repeatability of the ambulatory arterial stiffness index (AASI), which can be computed from 24-h blood pressure (BP) recordings as unity minus the regression slope of diastolic on systolic BP. METHODS: One hundred and fifty-two hypertensive outpatients recruited in Nijmegen (mean age = 46.2 years; 76.3% with systolic and diastolic hypertension) and 145 patients enrolled in the Systolic Hypertension in Europe (Syst-Eur) trial (71.0 years) underwent 24-h BP monitoring at a median interval of 8 and 31 days, respectively. We used the repeatability coefficient, which is twice the SD of the within-participant differences between repeat recordings, and expressed it as a percentage of four times the SD of the mean of the paired measurements. RESULTS: Mean AASI (crude or derived by time-weighted or robust regression) and 24-h pulse pressure (PP) were similar on repeat recordings in both cohorts. In Nijmegen patients, repeatability coefficients of AASI and PP were approximately 50%. In Syst-Eur trial patients, repeatability coefficient was approximately 60% for AASI and approximately 40% for PP. For comparison, repeatability coefficients for 24-h systolic and diastolic BP were approximately 30%. Differences in AASI between paired recordings were correlated with differences in the goodness of fit (r2) of the AASI regression line as well as with differences in the night-to-day BP ratio. However, in sensitivity analyses stratified for type of hypertension, r2, or dipping status, repeatability coefficients for AASI did not widely depart from 50 to 60% range. CONCLUSION: Estimates of mean AASI were not different between repeat recordings, and repeatability coefficients were within the 50-60% range.
Delaney A, Pellizzari M, Speiser PW, Frank GR. (Nov 2008). Pitfalls in the measurement of the nocturnal blood pressure dip in adolescents with type 1 diabetes. Diabetes Care. [Epub ahead of print]
OBJECTIVE: The purpose of this study was to screen adolescents with type 1 diabetes using ambulatory blood pressure monitoring (ABPM) to 1) test the hypothesis that using a preset sleep time results in an overdiagnosis of abnormal nocturnal dipping in systolic blood pressure and 2) assess the reproducibility of an abnormal nocturnal systolic blood pressure dip. RESEARCH DESIGN AND METHODS: For aim 1, ABPM from 53 adolescent patients with type 1 diabetes was reviewed. Nocturnal dips in systolic blood pressure calculated by actual sleep time were compared with those from a preset sleep time. For aim 2, blood pressure monitoring from 98 patients using actual reported sleep time was reviewed. Reproducibility of the nocturnal dip in systolic blood pressure was assessed in a subset of “nondippers.” RESULTS: For aim 1, the actual mean +/- SE decline in nocturnal systolic blood pressure was 11.6 +/- 4.7%, whereas the mean decline in nocturnal systolic blood pressure calculated using the preset sleep time was 8.8 +/- 4.9% (P < 0.0001). For aim 2, 64% of patients had a normal nocturnal decline in systolic blood pressure (14.9 +/- 3.1% mmHg), whereas 36% had an abnormal dip (5.7 +/- 2.8% mmHg). Repeat ABPM performed in 22 of the 35 nondippers revealed that only 36% had abnormal systolic dipping confirmed on the repeat ABPM. CONCLUSIONS: The use of actual reported sleep time is required to accurately determine the nocturnal dip in systolic blood pressure. Repeating ABPM in nondippers is essential to confirm this abnormality.
Denissen, Jaap J. A.; Butalid, Ligaya; Penke, Lars; van Aken, Marcel A. G. (Oct 2008). The effects of weather on daily mood: A multilevel approach. Emotion, Vol 8(5), pp. 662-667.
The present study examines the effects of six weather parameters (temperature, wind power, sunlight, precipitation, air pressure, and photoperiod) on mood (positive affect, negative affect, and tiredness). Data were gathered from an online diary study (N = 1,233), linked to weather station data, and analyzed by means of multilevel analysis. Multivariate and univariate analyses enabled distinction between unique and shared effects. The results revealed main effects of temperature, wind power, and sunlight on negative affect. Sunlight had a main effect on tiredness and mediated the effects of precipitation and air pressure on tiredness. In terms of explained variance, however, the average effect of weather on mood was only small, though significant random variation was found across individuals, especially regarding the effect of photoperiod. However, these individual differences in weather sensitivity could not be explained by the Five Factor Model personality traits, gender, or age.
Dollman J, Okely AD, Hardy L, Timperio A, Salmon J, Hills AP. (Nov 2008). A hitchhiker’s guide to assessing young people’s physical activity: Deciding what method to use. J Sci Med Sport. [Epub ahead of print]
Researchers and practitioners interested in assessing physical activity in children are often faced with the dilemma of what instrument to use. While there is a plethora of physical activity instruments to choose from, there is currently no guide regarding the suitability of common assessment instruments. The purpose of this paper is to provide a user’s guide for selecting physical activity assessment instruments appropriate for use with children and adolescents. While recommendations regarding specific instruments are not provided, the guide offers information about key attributes and considerations for the use of eight physical activity assessment approaches: heart rate monitoring; accelerometry; pedometry; direct observation; self-report; parent report; teacher report; and diaries/logs. Attributes of instruments and other factors to be considered in the selection of assessment instruments include: population (age); sample size; respondent burden; method/delivery mode; assessment time frame; physical activity information required (data output); data management; measurement error; cost (instrument and administration) and other limitations. A decision flow chart has been developed to assist researchers and practitioners to select an appropriate method of assessing physical activity. Five real-life scenarios are presented to illustrate this process in light of key instrument attributes. It is important that researchers, practitioners and policy makers understand the strengths and limitations of different methods of assessing physical activity, and are guided on selection of the most appropriate instrument/s to suit their needs.
Eguchi K, Ishikawa J, Hoshide S, Pickering TG, Schwartz JE, Shimada K, Kario K. (Oct 2008). Night Time Blood Pressure Variability Is a Strong Predictor for Cardiovascular Events in Patients With Type 2 Diabetes. Am J Hypertens. [Epub ahead of print]
BACKGROUND: We aimed this study to test the hypothesis that short-term blood pressure (BP) variability and abnormal patterns of diurnal BP variation, evaluated by ambulatory BP (ABP), predicts risk of incident cardiovascular disease (CVD) in patients with type 2 diabetes (T2DM). METHODS: ABP monitoring (ABPM) was performed in 300 patients with uncomplicated T2DM without known CVD and without BP medications, who were followed for 54 +/- 20 months. The relationships of different measures of BP variability, the presence of abnormal patterns of diurnal BP variation (nondipper, riser, or morning BP surge) and the standard deviations of awake and asleep ABP were determined. Cox proportional hazards models were used to estimate hazard ratios (HRs) and their 95% confidence intervals (CIs) before and after controlling for various covariates. RESULTS: The mean age was 67.8 +/- 9.6 years, 48% were male, 253 (84%) had a diagnosis of hypertension, and the mean of the standard deviations of awake systolic BP/diastolic BP (SBP/DBP) were 18 +/- 6/11 +/- 4 mm Hg, and those of sleep SBP/DBP were 13 +/- 5/9 +/- 3 mm Hg. During follow-up, there were 29 cardiovascular events. In multivariable analyses, the standard deviations of sleep SBP (HR = 1.08; 95% CI, 1.01-1.16, P < 0.05) and sleep DBP (HR = 1.13; 1.04-1.23, P < 0.01) were independently associated with incident CVD. Neither the nondipper and riser patterns nor the morning BP surge were associated with incident CVD events independently of clinic and 24-h BP levels. CONCLUSIONS: Abnormal diurnal BP variation was not a predictor of CVD in patients with T2DM. Night time BP variability was an independent predictor of future incidence of CVD, suggesting that this measure could reflect pathophysiology of T2DM.
Eguchi K, Pickering TG, Schwartz JE, Hoshide S, Ishikawa J, Ishikawa S, Shimada K, Kario K. (Nov 2008). Short sleep duration as an independent predictor of cardiovascular events in Japanese patients with hypertension. Arch Intern Med. 168(20):2225-31.
BACKGROUND: It is not known whether short duration of sleep is a predictor of future cardiovascular events in patients with hypertension. METHODS: To test the hypothesis that short duration of sleep is independently associated with incident cardiovascular diseases (CVD), we performed ambulatory blood pressure (BP) monitoring in 1255 subjects with hypertension (mean [SD] age, 70.4 [9.9] years) and followed them for a mean period of 50 (23) months. Short sleep duration was defined as less than 7.5 hours (20th percentile). Multivariable Cox hazard models predicting CVD events were used to estimate the adjusted hazard ratio and 95% confidence interval (CI) for short sleep duration. A riser pattern was defined when mean nighttime systolic BP exceeded daytime systolic BP. The end point was a cardiovascular event: stroke, fatal or nonfatal myocardial infarction (MI), and sudden cardiac death. RESULTS: In multivariable analyses, short duration of sleep (<7.5 hours) was associated with incident CVD (hazard ratio [HR], 1.68; 95% CI, 1.06-2.66; P = .03). A synergistic interaction was observed between short sleep duration and the riser pattern (P = .09). When subjects were classified according to their sleep time and a riser vs nonriser pattern, the group with shorter sleep duration plus the riser pattern had a substantially and significantly higher incidence of CVD than the group with predominant normal sleep duration plus the nonriser pattern (HR, 4.43; 95% CI, 2.09-9.39; P < .001), independent of covariates. CONCLUSIONS: Short duration of sleep is associated with incident CVD risk and the combination of the riser pattern and short duration of sleep that is most strongly predictive of future CVD, independent of ambulatory BP levels. Physicians should inquire about sleep duration in the risk assessment of patients with hypertension.
Eiholzer U, Meinhardt U, Rousson V, Petrò R, Schlumpf M, Fusch G, Fusch C, Gasser T, Gutzwiller F. (Nov 2008). Association between short sleeping hours and physical activity in boys playing ice hockey. J Pediatr. 153(5):640-5, 645.e1.
OBJECTIVES: To determine physical activity in healthy boys and how physical activity relates to training and daily awake hours. STUDY DESIGN: In 66 boys (5 to 15 years) affiliated with an ice-hockey club, we measured total daily energy expenditure (TDEE, doubly-labeled water) and basal metabolic rate (ventilated-hood method). Physical activity energy expenditure for the whole day (DAEE), during training, and during spontaneous physical activity was measured by accelerometry and activity protocols. Univariate (UA) and multivariate (MA) correlation analysis was applied. RESULTS: Physical activity level, DAEE, and TDEE for prepubertal (2.0 and 2.2 Mcal/d) and pubertal (bone age >or=13 years; 1.8 and 2.8 Mcal/d) boys were matched to literature data from normal boys of equal age. In prepubertal boys DAEE correlated positively with awake hours (r(UA) = 0.55, r(MA) = 0.39, P < .01). In pubertal boys this correlation was not significant, the slopes between the 2 groups being significantly different (P = .025). In prepubertal boys spontaneous physical activity expenditure correlated significantly positively with training activity expenditure (r(UA) = 0.72, r(MA) = 0.52, P < .001). CONCLUSION: Contrary to findings in adults, where short sleepers had lower physical activity and intensive training was negatively compensated reducing spontaneous physical activity, in physically active prepubertal boys, total daily and spontaneous physical activity relate positively to awake hours and training; suggesting child-specific control of physical activity.
Forbes EE, Hariri AR, Martin SL, Silk JS, Moyles DL, Fisher PM, Brown SM, Ryan ND, Birmaher B, Axelson DA, Dahl RE. (Dec 2008). Altered Striatal Activation Predicting Real-World Positive Affect in Adolescent Major Depressive Disorder. Am J Psychiatry. [Epub ahead of print]
Objective Alterations in reward-related brain function and phenomenological aspects of positive affect are increasingly examined in the development of major depressive disorder. The authors tested differences in reward-related brain function in healthy and depressed adolescents, and the authors examined direct links between reward-related brain function and positive mood that occurred in real-world contexts. Method Fifteen adolescents with major depressive disorder and 28 adolescents with no history of psychiatric disorder, ages 8-17 years, completed a functional magnetic resonance imaging guessing task involving monetary reward. Participants also reported their subjective positive affect in natural environments during a 4-day cell-phone-based ecological momentary assessment. Results Adolescents with major depressive disorder exhibited less striatal response than healthy comparison adolescents during reward anticipation and reward outcome, but more response in dorsolateral and medial prefrontal cortex. Diminished activation in a caudate region associated with this depression group difference was correlated with lower subjective positive affect in natural environments, particularly within the depressed group. Conclusions Results support models of altered reward processing and related positive affect in young people with major depressive disorder and indicate that depressed adolescents’ brain response to monetary reward is related to their affective experience in natural environments. Additionally, these results suggest that reward-processing paradigms capture brain function relevant to real-world positive affect.
Fukuda M, Mizuno M, Yamanaka T, Motokawa M, Shirasawa Y, Nishio T, Miyagi S, Yoshida A, Kimura G. (Dec 2008). Patients with renal dysfunction require a longer duration until blood pressure dips during the night. Hypertension. 52(6):1155-60.
We have postulated that the diminished renal capacity to excrete sodium causes nocturnal blood pressure (BP) elevation, which enhances pressure natriuresis in compensation for impaired daytime natriuresis. If such a mechanism holds, high BP during sleep at night may continue until excess sodium is sufficiently excreted into urine. This study examined whether the duration, defined as “dipping time,” until nocturnal mean arterial pressure began to fall to <90% of daytime average became longer as renal function deteriorated. Ambulatory BP measurements and urinary sodium excretion rates were evaluated for daytime and nighttime to estimate their circadian rhythms in 65 subjects with chronic kidney disease. Dipping time showed an inverse relationship with creatinine clearance (C(cr); rho=-0.61; P<0.0001) and positive relationships with night/day ratios of mean arterial pressure (rho=0.84; P<0.0001) and natriuresis (rho=0.61; P<0.0001), both of which were also inversely correlated with C(cr) (mean arterial pressure: r=-0.58, P<0.0001; natriuresis: r=-0.69, P<0.0001). When divided into tertiles by C(cr) (mL/min), hazard ratios of nocturnal BP dip adjusted for age, gender, and body mass index were 0.37 (95% CI: 0.17 to 0.79; P=0.01) for the second tertile (C(cr): 50 to 90) and 0.20 (95% CI: 0.08 to 0.55; P=0.002) for the third tertile (C(cr): 5 to 41) compared with the first tertile (C(cr): 91 to 164). These findings demonstrate that patients with renal dysfunction require a longer duration until BP falls during the night. The prolonged duration until BP dip during sleep seems an essential component of the nondipper pattern of the circadian BP rhythm.
Gaborieau V, Delarche N, Gosse P. (Oct 2008). Ambulatory blood pressure monitoring versus self-measurement of blood pressure at home: correlation with target organ damage. J Hypertens. 26(10):1919-27.
OBJECTIVE: Ambulatory blood pressure (BP) monitoring and home blood pressure measurements predicted the presence of target organ damage and the risk of cardiovascular events better than did office blood pressure. METHODS: To compare these two methods in their correlation with organ damage, we consecutively included 325 treated (70%) or untreated hypertensives (125 women, mean age = 64.5 +/- 11.3) with office (three measurements at two consultations), home (three measurements morning and evening over 3 days) and 24-h ambulatory monitoring. Target organs were evaluated by ECG, echocardiography, carotid echography and detection of microalbuminuria. Data from 302 patients were analyzed. RESULTS: Mean BP levels were 142/82 mmHg for office, 135.5/77 mmHg for home and 128/76 mmHg for 24-h monitoring (day = 130/78 mmHg; night = 118.5/67 mmHg). With a 135 mmHg cut-off, home and daytime blood pressure diverged in 20% of patients. Ambulatory and Home blood pressure were correlated with organ damage more closely than was office BP with a trend to better correlations with home BP. Using regression analysis, a 140 mmHg home systolic blood pressure corresponded to a 135 mmHg daytime systolic blood pressure; a 133 mmHg daytime ambulatory blood pressure and a 140 mmHg home blood pressure corresponded to the same organ damage cut-offs (Left ventricular mass index = 50 g/m, Cornell.QRS = 2440 mm/ms, carotid intima media thickness = 0.9 mm). Home-ambulatory differences were significantly associated with age and antihypertensive treatment. CONCLUSION: We showed that home blood pressure was at least as well correlated with target organ damage, as was the ambulatory blood pressure. Home-ambulatory correlation and their correlation with organ damage argue in favor of different cut-offs, that are approximately 5 mmHg higher for systolic home blood pressure.
Gardner AW, Montgomery PS, Scott KJ, Blevins SM, Afaq A, Nael R. (Nov 2008). Association between daily ambulatory activity patterns and exercise performance in patients with intermittent claudication. J Vasc Surg. 48(5):1238-44.
PURPOSE: To determine the association between daily ambulatory activity patterns and exercise performance in patients with intermittent claudication. METHODS: One hundred thirty-three patients limited by intermittent claudication participated in this study. Patients were assessed on their ambulatory activity patterns for 1 week with a small, lightweight step activity monitor attached to the ankle using elastic velcro straps above the lateral malleolus of the right leg. The step activity monitor recorded the number of strides taken on a minute-to-minute basis and the time spent ambulating. Patients also were characterized on ankle-brachial index (ABI), ischemic window (IW) after a treadmill test, as well as initial claudication distance (ICD), and absolute claudication distance (ACD) during treadmill exercise. RESULTS: The patient characteristics (mean +/- SD) were as follows: ABI = 0.71 +/- 0.23, IW = 0.54 +/- 0.72 mm Hg.min.meter(-1), ICD = 236 +/- 198 meters, and ACD = 424 +/- 285 meters. The patients took 3366 +/- 1694 strides/day, and were active for 272 +/- 103 min/day. The cadence for the 30 highest, consecutive minutes of each day (15.1 +/- 7.2 strides/min) was correlated with ICD (r = 0.316, P < .001) and ACD (r = 0.471, P < 0.001), and the cadence for the 60 highest, consecutive minutes of each day (11.1 +/- 5.4 strides/min) was correlated with ICD (r = 0.290, P < .01) and ACD (r = 0.453, P < .001). Similarly, the cadences for the highest 1, 5, and 20 consecutive minutes, and the cadence for the 30 highest, nonconsecutive minutes all were correlated with ICD and ACD (P < .05). None of the ambulatory cadences were correlated with ABI (P > .05) or with ischemic window (P > .05). CONCLUSION: Daily ambulatory cadences are associated with severity of intermittent claudication, as measured by ACD and ICD, but not with peripheral hemodynamic measures.
Gebruers N, Truijen S, Engelborghs S, Nagels G, Brouns R, De Deyn PP. (Nov 2008). Actigraphic measurement of motor deficits in acute ischemic stroke. Cerebrovasc Dis. 26(5):533-40.
BACKGROUND: This study aimed to investigate the use of actigraphy (accelerometry) to measure disuse of the impaired arm in acute stroke patients. We correlated the National Institute of Health Stroke Scale (NIHSS) and the Fugl-Meyer Assessment arm section (FMA) findings with actigraphic data as a measure of validity. METHODS: Thirty-nine acute ischemic stroke patients were included within 1 week after stroke onset. At inclusion, motor deficits were assessed by the NIHSS, FMA and 48-hour actigraphic recordings of both wrists were performed. RESULTS: Moderate but highly significant correlations (Spearman’s rho) between actigraphic recordings and total NIHSS (ratio r = -0.59 and activity of impaired arm r = -0.75; p < 0.001) and FMA (ratio r = 0.54 and activity of impaired arm r = 0.69; p < 0.001) scores were found. Based on actigraphic motor activity scores, ROC curves were calculated following dichotomization of the population based on NIHSS = 7 and FMA = 45, showing good sensitivity and specificity, with negative predictive value of 100% and positive predictive value of 91% for the ratio variable. CONCLUSIONS: Moderate but highly significant correlations were found between actigraphy and the stroke scales NIHSS and FMA. Actigraphy was able to reliably discriminate less impaired from more impaired stroke patients with excellent sensitivity and specificity values. Actigraphy is a simple, valid, objective and reliable clinical research tool that can be used to determine motor impairment of the upper limb in stroke patients. 2008 S. Karger AG, Basel.
Godfrey A, Conway R, Meagher D, Olaighin G. (Dec 2008). Direct measurement of human movement by accelerometry. Med Eng Phys. 30(10):1364-86.
Human movement has been the subject of investigation since the fifth century when early scientists and researchers attempted to model the human musculoskeletal system. The anatomical complexities of the human body have made it a constant source of research to this day with many anatomical, physiological, mechanical, environmental, sociological and psychological studies undertaken to define its key elements. These studies have utilised modern day techniques to assess human movement in many illnesses. One such modern technique has been direct measurement by accelerometry, which was first suggested in the 1970s but has only been refined and perfected during the last 10-15 years. Direct measurement by accelerometry has seen the introduction of the successful implementation of low power, low cost electronic sensors that have been employed in clinical and home environments for the constant monitoring of patients (and their controls). The qualitative and quantitative data provided by these sensors make it possible for engineers, clinicians and physicians to work together to be able to help their patients in overcoming their physical disability. This paper presents the underlying biomechanical elements necessary to understand and study human movement. It also reflects on the sociological elements of human movement and why it is important in patient life and well being. Finally the concept of direct measurement by accelerometry is presented with past studies and modern techniques used for data analysis.
Graves LE, Ridgers ND, Stratton G. (Nov 2008). The contribution of upper limb and total body movement to adolescents’ energy expenditure whilst playing Nintendo Wii. Eur J Appl Physiol. 104(4):617-23.
Little research documents the contribution of upper limb and total body movement to energy expenditure (EE) during active video gaming. To address this, EE, heart rate (HR), and, upper limb and total body movement were assessed in 11- to 17-year-old adolescents whilst playing three active (Nintendo Wii) and one sedentary (XBOX 360) video games. Non-dominant upper limb activity, EE and HR were significantly greater during Wii Sports boxing [mean 267.2 (SD 115.8) J kg(-1) min(-1); 136.7 (24.5) beats min(-1)] than tennis or bowling (P < or = 0.044). For all active games hip activity best predicted EE (R (2) > or = 0.53), with two-measure models of HR and single-site activity data, and multi-site activity data, similarly explaining the variance in EE (R (2) > or = 0.64). The physiological cost of upper-body orientated active video games increased when movement of both upper limbs was encouraged. Improvements in EE explanatory power provide support for multi-site activity monitoring during unique, non-ambulatory activities.
Grover SS, Pittman SD. (Nov 2008). Automated detection of sleep disordered breathing using a nasal pressure monitoring device. Sleep Breath. 12(4):339-45.
To assess the accuracy of a single channel portable monitoring device (RUSleepingtrade mark RTS, Respironics, Murrysville, PA) that measures nasal pressure (a surrogate for airflow) to detect sleep disordered breathing (SDB). Twenty-five adult patients referred to a community sleep laboratory with suspected obstructive sleep apnea (OSA) participated in this investigation. The portable monitoring device was used in the sleep laboratory to acquire data concurrently with a standard multi-channel polysomnogram (PSG) to assess SDB. Respiratory events were scored manually on the PSG using standard criteria for clinical research to quantify an apnea-hypopnea index (AHI) based on events during sleep. The portable monitoring device automatically calculated an unedited respiratory event index (REI) based on recording time. These data were then compared using the Pearson product-moment correlation coefficient, Bland-Altman analysis, receiver operating characteristic (ROC) curves, and likelihood ratios. All 25 subjects completed the study. Mean age of subjects was 42.4 +/- 12.9 years and mean body mass index was 31.0 +/- 7.4 kg m(-2). There was good agreement between the REI and the AHI (R = 0.77, p < 0.001, mean difference 2.6 events per hour [2 SD: 39.8] using a Bland-Altman plot). The area under the ROC curve for detecting SDB (PSG AHI greater than or equal to five events per hour) with the REI was 0.94 (95% CI 0.84-1.0). For an REI >11.9 events per hour, the sensitivity was 0.89 (95% CI 0.65-0.99) and the specificity was 0.86 (95% CI 0.42-1.0) with a likelihood ratio of 6.2 for a positive test (LR+) and 0.13 for a negative test (LR-). Similar results were observed for detecting moderate-severe SDB (PSG AHI > or = 15 events h(-1)) using REI >15.2 events h(-1). In a population of subjects with suspected OSA, this portable monitoring device can automatically quantify an REI that compares well to the AHI scored manually on a concurrent PSG. Such a device may prove useful to assess SDB in high risk populations with self-administered testing in ambulatory settings such as the home.
Gulur P, Rodi SW, Washington TA, Cravero JP, Fanciullo GJ, McHugo GJ, Baird JC. (Nov 2008). Computer Face Scale for Measuring Pediatric Pain and Mood. J Pain. [Epub ahead of print]
This investigation determined the psychometric properties and acceptability of an animated face scale presented on a hand-held computer as a means to measure pediatric pain and mood. In study 1, 79 hospitalized, pediatric patients indicated their levels of pain by adjusting the expression of an animated cartoon face. The first objective was to determine feasibility, concurrent validity, and acceptability of the method. All patients were tested both with the Computer Face Scale and the poster format of the Wong-Baker Faces Scale. A second objective was to evaluate test-retest reliability of the method. In study 2, 50 hospitalized, pediatric patients were tested on 2 occasions, but in this case the patients used the Computer Face Scale to indicate both their pain (how much they hurt) and their mood (how they felt). Children in study 1 were able to use the Computer Face Scale to express relative amounts of pain/hurt; the method showed concurrent validity with the Wong-Baker Face Scale; and most children expressed a preference for the Computer Face Scale. The method also showed adequate test-retest reliability. In study 2, adequate test-retest reliability was demonstrated for ratings of both pain and mood. PERSPECTIVE: The Computer Face Scale allows the health provider to obtain reliable and valid measures of pediatric pain and mood. The method can be understood and used by children as young as 3 years and is appropriate for use with adults.
Hagströmer M, Bergman P, De Bourdeaudhuij I, Ortega FB, Ruiz JR, Manios Y, Rey-López JP, Phillipp K, von Berlepsch J, Sjöström M; HELENA Study Group. (Nov 2008). Concurrent validity of a modified version of the International Physical Activity Questionnaire (IPAQ-A) in European adolescents: The HELENA Study. Int J Obes (Lond). 32 Suppl 5:S42-8.
INTRODUCTION: The International Physical Activity Questionnaire (IPAQ) was developed to measure health-enhancing physical activity in adult populations. This study explores the concurrent validity of a modified version of the long IPAQ (the IPAQ-A) for the assessment of physical activity among adolescents. PARTICIPANTS AND METHODS: In total, 248 healthy adolescents, divided into one older and one younger age group (aged 15-17 years (N=188) and 12-14 years (N=60), respectively) from nine Healthy Lifestyle by Nutrition in Adolescence (HELENA) Study centres across Europe, voluntarily participated in the study. Data on total physical activity, as well as activities in different intensities derived from the IPAQ-A, were compared using Spearman’s correlation coefficient and Bland-Altman analysis, with data from an accelerometer. Tertiles of total physical activity for the IPAQ-A and the accelerometer were compared using Kendall’s tau-b. RESULTS: For the older age group, significant correlations between the instruments were found for time spent walking, for moderate and vigorous activities as well as for total physical activity (Rs=0.17-0.30, P<0.05). No significant correlations were found for any of the variables studied in the younger age group. Kendall’s tau-b showed low but significant correlations for tertiles of total physical activity (P<0.001). CONCLUSIONS: The IPAQ-A has reasonable validity properties for assessing activities in different intensities and for total physical activity in healthy European adolescents aged 15-17 years. For adolescents aged 14 years and younger, the correlations were unsatisfactorily low and objective methodology, such as accelerometry, may be the appropriate alternative.
Håkanson BS, Berggren P, Granqvist S, Ljungqvist O, Thorell A. (Nov 2008). Comparison of wireless 48-h (Bravo) versus traditional ambulatory 24-h esophageal pH monitoring. Scand J Gastroenterol [Epub ahead of print]
Objective. To compare wireless with catheter-based esophageal pH recordings. Material and methods. Forty-five patients with symptoms suggestive of gastroesophageal reflux disease and 47 healthy volunteers were investigated in a university-affiliated hospital; 48-h wireless esophageal pH recording was performed. During the first 24 h, simultaneous traditional pH recording by catheter was undertaken. Nine of the volunteers underwent repeated measurements with both techniques. Outcome measures were feasibility, agreement, concordance of diagnostic yield, reproducibility, and subjective symptoms. Results. Subjective parameters were less affected when using the wireless technique alone (p<0.05). On using the wireless technique, esophageal acid exposure was underestimated approximately by half compared with traditional recording (p<0.05). Although pH data obtained with the two techniques were correlated (r(2)=0.66, p<0.001), the range between limits of agreement was wide (-3.7 to 10.0 percentage units of total time pH <4). Coefficients of variation for repeated measurements were 60.1+/-26.3% for catheter recordings, and 66.0+/-47.3 for wireless recordings on day 1 (NS). Concordance of diagnostic yield was 81.5% with all subjects included. Conclusions. Forty-eight-hour wireless Bravo pH monitoring is feasible but consistently underestimates esophageal acid exposure compared to the conventional technique. Although there is a significant correlation between the two techniques for pH recordings, the wide range in limits of agreement and the large coefficient of variation with both techniques suggest that the two methods are not immediately interchangeable for use in clinical practice.
Halsey LG, Green JA, Wilson RP, Frappell PB. (Nov 2008). Accelerometry to Estimate Energy Expenditure during Activity: Best Practice with Data Loggers. Physiol Biochem Zool. [Epub ahead of print]
Abstract Measurement of acceleration can be a proxy for energy expenditure during movement. The variable overall dynamic body acceleration (ODBA), used in recent studies, combines the dynamic elements of acceleration recorded in all three dimensions to measure acceleration and hence energy expenditure due to body movement. However, the simplicity of ODBA affords it limitations. Furthermore, while accelerometry data loggers enable measures to be stored, recording at high frequencies represents a limit to deployment periods as a result of logger memory and/or battery exhaustion. Using bantam chickens walking at different speeds in a respirometer while wearing an accelerometer logger, we investigated the best proxies for rate of oxygen consumption ([Formula: see text]) from a range of different models using acceleration. We also investigated the effects of sampling acceleration at different frequencies. The best predictor of [Formula: see text] was a multiple regression including individual measures of dynamic acceleration in each of the three dimensions. However, R(2) was relatively high for ODBA as well and also for certain measures of dynamic acceleration in single dimensions. The aforementioned are single variables, therefore easily derived onboard a data logger and from which a simple calibration equation can be derived. For calibrations of [Formula: see text] against ODBA, R(2) was consistent as sampling number decreased down to 600 samples of each acceleration channel per ODBA data point, beyond which R(2) tended to be considerably lower. In conclusion, data storage can be maximized when using acceleration as a proxy for [Formula: see text] by consideration of reductions in (1) number of axes measured and (2) sampling frequency.
Hanss R, Block D, Bauer M, Ilies C, Magheli A, Schildberg-Schroth H, Renner J, Scholz J, Bein B. (Nov 2008). Use of heart rate variability analysis to determine the risk of cardiac ischaemia in high-risk patients undergoing general anaesthesia. Anaesthesia. 63(11):1167-73.
The aim of this study was to investigate the use of pre-operative heart rate variability analysis to predict postoperative cardiac events (identified by 24 h Holter-ECG recording and an increase of creatine kinase MB) in high-risk cardiac patients. Length of hospital stay, the incidence of postoperative cardiac ischaemia and cardiac events after discharge were recorded. Fifty patients were assigned by the presence of cardiac events and the heart rate variability in 17 patients with an event was compared with 33 patients without. Total power was identified as a predictive parameter. The usefulness of this test was assessed in a second group of 50 patients. The incidence of cardiac events detected by Holter-ECG recording or an increased creatine kinase MB was greater and the duration of hospital stay longer in the 26 patients with total power < 400 ms(2).Hz(-1) compared with those with total power > 400 ms(2).Hz(-1) (eight and four patients and 10 (7) days (mean (SD)), vs 1 (p < 0.05) and 0 (p < 0.05) patients and 6 (2) days (p < 0.05), respectively). The total power of high-risk cardiac patients predicted postoperative cardiac events and extended length of hospital stay.
Hay DC, Wakayama A, Sakamura K, Fukashiro S. (Dec 2008). Improved estimation of energy expenditure by artificial neural network modeling. Appl Physiol Nutr Metab. 33(6):1213-22.
Estimation of energy expenditure in daily living conditions can be a tool for clinical assessment of health status, as well as a self-measure of lifestyle and general activity levels. Criterion measures are either prohibitively expensive or restricted to laboratory settings. Portable devices (heart rate monitors, pedometers) have gained recent popularity, but accuracy of the prediction equations remains questionable. This study applied an artificial neural network modeling approach to the problem of estimating energy expenditure with different dynamic inputs (accelerometry, heart rate above resting (HRar), and electromyography (EMG)). Nine feed-forward back-propagation models were trained, with the goal of minimizing the mean squared error (MSE) of the training datasets. Model 1 (accelerometry only) and model 2 (HRar only) performed poorly and had significantly greater MSE than all other models (p < 0.001). Model 3 (combined accelerometry and HRar) had overall performance similar to EMG models. Validation of all models was performed by simulating untrained datasets. MSE of all models increased when tested with validation data. While models 1 and 2 again performed poorly, model 3 MSE was lower than all but 2 EMG models. Squared correlation coefficients of measured and predicted energy expenditure for models 3 to 9 ranged from 0.745 to 0.817. Analysis of mean error within specific movement categories indicates that EMG models may be better at predicting higher-intensity energy expenditure, but combined accelerometry and HRar provides an economical solution, with sufficient accuracy.
Hilbert A, Rief W, Tuschen-Caffier B, de Zwaan M, Czaja J. (Oct 2008). Loss of control eating and psychological maintenance in children: An ecological momentary assessment study. Behav Res Ther. [Epub ahead of print]
OBJECTIVE: Recent research suggests that binge eating is a common experience in youth. However, it remains largely unknown how children’s binge eating presents in everyday life and which psychological factors serve to maintain this binge eating. METHODS: Children aged 8-13 years with binge eating (n=59), defined as at least one episode of loss of control (LOC) over eating within the past three months, and 59 matched children without LOC history were recruited from the community. Following a combined random- and event-sampling protocol, children were interviewed about their day-to-day eating behavior, mood, and eating disorder-specific cognitions using child-specific cell phones during a 4-day assessment period in their natural environment. RESULTS: LOC episodes led to a significantly greater intake of energy, particularly from carbohydrates, than regular meals of children with and without LOC eating. While LOC episodes were preceded and followed by cognitions about food/eating and body image, there was minimal evidence that negative mood states were antecedents of LOC eating. CONCLUSIONS: The results provide support for the construct validity of LOC eating in children. Maintenance theories of binge eating for adults apply to children regarding eating disorder-specific cognitions, but the association with affect regulation difficulties requires further investigation.
Holt-Lunstad J, Birmingham WA, Light KC. (Nov 2008). Influence of a “warm touch” support enhancement intervention among married couples on ambulatory blood pressure, oxytocin, alpha amylase, and cortisol. Psychosom Med. 70(9):976-85.
OBJECTIVE: To investigate whether a support intervention (warm touch enhancement) influences physiological stress systems that are linked to important health outcomes. Growing evidence points to a protective effect of social and emotional support on both morbidity and mortality. METHODS: In this study, 34 healthy married couples (n = 68), aged 20 to 39 years (mean = 25.2 years), were randomly assigned to a “behavior monitoring” control group or participated in a 4-week intervention study in which clinic levels of plasma oxytocin, 24-hour ambulatory blood pressure, and salivary cortisol and alpha amylase were obtained pre and post intervention, at the same time salivary oxytocin was taken at home during weeks 1 and 4. RESULTS: Salivary oxytocin was enhanced both early and late in the intervention group and alpha amylase was reduced at post treatment in intervention group husbands and wives relative to controls. Husbands in the intervention group had significantly lower post treatment 24-hour systolic blood pressure than the control group. CONCLUSION: Increasing warm touch among couples has a beneficial influence on multiple stress-sensitive systems.
Ishikawa J, Carroll DJ, Kuruvilla S, Schwartz JE, Pickering TG. (Nov 2008). Changes in home versus clinic blood pressure with antihypertensive treatments: a meta-analysis. Hypertension. 52(5):856-64.
Home blood pressure (HBP) monitoring is recommended for assessing the effects of antihypertensive treatment, but it is not clear how the treatment-induced changes in HBP compare with the changes in clinic blood pressure (CBP). We searched PubMed using the terms “home or self-measured blood pressure,” and selected articles in which the changes in CBP and HBP (using the upper arm oscillometric method) induced by antihypertensive drugs were presented. We performed a systematic review of 30 articles published before March 2008 that included a total of 6794 subjects. As there was significant heterogeneity in most of the outcomes, a random effects model was used for the meta-analyses. The mean changes (+/-SE) in CBP and HBP (systolic/diastolic) were -15.2+/-0.03/-10.3+/-0.03 mm Hg and -12.2+/-0.04/-8.0+/-0.04 mm Hg respectively, although there were wide varieties of differences in the reduction between HBP and CBP. The reductions in CBP were correlated with those of HBP (systolic BP; r=0.66, B=0.48, diastolic BP; r=0.71, B=0.52, P<0.001). In 7 studies that also included 24-hour BP monitoring, the reduction of HBP was greater than that of 24-hour BP in systolic (HBP; -12.6+/-0.06 mm Hg, 24-hour BP; -11.9+/-0.04 mm Hg, P<0.001). In 5 studies that included daytime and nighttime systolic BP separately, HBP decreased 15% more than daytime ambulatory BP and 30% more than nighttime ambulatory BP. In conclusion, HBP falls approximately 20% less than CBP with antihypertensive treatments. Daytime systolic BP falls 15% less and nighttime systolic BP falls 30% less than home systolic BP.
Jahng, Seungmin; Wood, Phillip K.; Trull, Timothy J. (Dec 2008). Analysis of affective instability in ecological momentary assessment: Indices using successive difference and group comparison via multilevel modeling. Psychological Methods, Vol 13(4), pp. 354-375.
Temporal instability of affect is a defining characteristic of psychological disorders such as borderline personality disorder (BPD) and mood cycling disorders. Ecological momentary assessment (EMA) enables researchers to directly assess such frequent and extreme fluctuations over time. The authors examined 4 operationalizations of such temporal instability: the within-person variance (WPV), the first-order autocorrelation, the mean square successive difference (MSSD), and the probability of acute change (PAC). It is argued that the MSSD and PAC measures are preferred indices of affective instability because they capture both variability and temporal dependency in a time series. Additionally, the performance of these 2 measures in capturing within- and between-day instability is discussed. To illustrate, the authors present EMA data from a study of negative mood in BPD and major depressive disorder patients. In this study, MSSD and PAC captured affective instability better than did WPV. Given that MSSD and PAC are individual difference measures, the authors propose that group differences on these indices be explored using generalized multilevel models. Versions of MSSD and PAC that adjust for randomly elapsed time interval between assessments are also presented.
Janssen WG, Külcü DG, Horemans HL, Stam HJ, Bussmann JB. (Oct 2008). Sensitivity of accelerometry to assess balance control during sit-to-stand movement. IEEE Trans Neural Syst Rehabil Eng. 16(5):479-84.
Accelerometry has the potential to measure balance, defined as high-frequency body sway, ambulatorily in a simple and inexpensive way. The aim of this study was to determine and compare the sensitivity of accelerometric balance parameters during the sit-to-stand (STS) movement. Eleven healthy subjects (four males, 28.2 +/-7.9 years) and 31 patients with stroke (21 males; 63.3+/-12.8 years) were included. The healthy subjects performed STS movements in four conditions with different levels of difficulty. Data of the patients were compared 1) with healthy subjects, 2) between patient subgroups, and 3) between different phases of recovery to assess the sensitivity of accelerometry for differences in balance control. Accelerometers were attached to the trunk, and force plate measurements were simultaneously done in the healthy subjects. Main outcome measures were root mean square (rms) and area under the curve (AUC) derived from the high-frequency component of the transversal acceleration signal of the trunk. In all comparisons there was a significant difference in AUC data ( p < 0.05), and AUC appeared to be more sensitive than rms. Variability in AUC was not completely or mainly the result of changes and differences in the duration of the STS movement. As a conclusion, accelerometry is a potentially valuable technique to measure balance during the STS movement.
Jones DP, Richey PA, Alpert BS. (Dec 2008). Validation of the AM5600 ambulatory blood pressure monitor in children and adolescents. Blood Press Monit. 13(6):349-51.
OBJECTIVE: We measured ambulatory blood pressure using the AM5600 in children and adolescents participating in a research study to assess the relationship of blood pressure to risk factors for cardiovascular disease. Although the use of this monitor has been previously reported in adults, it has not been validated in pediatric patients. PARTICIPANTS AND METHODS: In this study, we assess the accuracy of the monitor as compared with the mercury sphygmomanometer in children of 7-18 years of age. RESULTS: We found that the mean of the difference between the monitor and the mercury device was 0.29+/-3.5 and 0.045+/-3.7 mmHg for systolic and diastolic blood pressure, respectively, which fulfills the Advancement of Medical Instrumentation standard for use of a device. The cumulative percentage of readings between the two devices which differed by 5, 10 and 15 mmHg or more assigned a grade of A grade to the device according to the British Hypertension Society. CONCLUSION: The AM5600 ambulatory blood pressure device is valid for measurement of blood pressure in children and adolescents.
Jung W, Rillig A, Birkemeyer R, Miljak T, Meyerfeldt U. (Oct 2008). Advances in remote monitoring of implantable pacemakers, cardioverter defibrillators and cardiac resynchronization therapy systems. J Interv Card Electrophysiol. 23(1):73-85.
Unlike the standard quarterly or semi-annual direct ambulatory device interrogations procedures, state-of-the-art implantable electronic cardiovascular devices (IECD) enable their wireless remote interrogation and monitoring, and automatically send reports and special alerts on a daily basis. This allows physicians to respond more proactively to changes in patient or device status, more appropriately triage patient care, and more efficiently perform the post-implant ambulatory follow-ups. This review presents the-state-of the-art technology of remote IECD monitoring and summarizes the main clinical observations published through June 2008. Cardiovascular remote monitoring systems made by several manufacturers are currently in various phases of development, clinical investigation, and medical applications. Data collected in several completed and ongoing studies strongly suggest that this new technology will make important contributions, particularly with respect to the facilitation of IECD follow-ups, enhancement of patient safety and quality of life, and lowering of medical costs. Further technological advances and a more clear understanding and appreciation of the clinical and economic benefits of telecardiology, will likely increase sharply the use of remote IECD monitoring in upcoming years.
Juslin, Patrik N.; Liljeström, Simon; Västfjäll, Daniel; Barradas, Gonçalo; Silva, Ana (Oct 2008). An experience sampling study of emotional reactions to music: Listener, music, and situation. Emotion, Vol 8(5), pp. 668-683.
The Experience Sampling Method was used to explore emotions to music as they naturally occurred in everyday life, with a focus on the prevalence of different musical emotions and how such emotions are related to various factors in the listener, the music, and the situation. Thirty-two college students, 20 to 31 years old, carried a palmtop that emitted a sound signal seven times per day at random intervals for 2 weeks. When signaled, participants were required to complete a questionnaire on the palmtop. Results showed that music occurred in 37% of the episodes, and in 64% of the music episodes, the participants reported that the music affected how they felt. Comparisons showed that happiness-elation and nostalgia-longing were more frequent in episodes with musical emotions, whereas anger-irritation, boredom-indifference, and anxiety-fear were more frequent in episodes with nonmusical emotions. The prevalence of specific musical emotions correlated with personality measures and also varied depending on the situation (e.g., current activity, other people present), thus highlighting the need to use representative samples of situations to obtain valid estimates of prevalence.
Juth, Vanessa; Smyth, Joshua M.; Santuzzi, Alecia M. (Oct 2008). How do you feel?: Self-esteem predicts affect, stress, social interaction, and symptom severity during daily life in patients with chronic illness. Journal of Health Psychology, Vol 13(7), pp. 884-894.
Self-esteem has been demonstrated to predict health and well-being in a number of samples and domains using retrospective reports, but little is known about the effect of self-esteem in daily life. A community sample with asthma (n = 97) or rheumatoid arthritis (n = 31) completed a self-esteem measure and collected Ecological Momentary Assessment (EMA) data 5x/day for one week using a palmtop computer. Low self-esteem predicted more negative affect, less positive affect, greater stress severity, and greater symptom severity in daily life. Naturalistic exploration of mechanisms relating self-esteem to physiological and/or psychological components in illness may clarify causal relationships and inform theoretical models of self-care, well-being, and disease management.
Katz PO, Matheus T. (Dec 2008). Telemetry Capsule for Ambulatory pH Monitoring: Is It Time for a Change? Am J Gastroenterol. 103(12):2986-7.
There is currently no clear gold standard for the diagnosis of gastroesophageal reflux disease. The most common practice, a therapeutic trial of antisecretory therapy, falls short of being ideal. Endoscopy is insensitive and impractical as an early diagnostic test for the majority of patient presentations. Ambulatory reflux monitoring offers the most effective means of documenting the presence of abnormal esophageal acid exposure and abnormal reflux frequency and to correlate the association of symptoms and reflux episodes. However, even this diagnostic test has fallen short of being an adequate and reliable standard for diagnosis. Telemetry capsule monitoring offers the opportunity for creative improvement in the diagnostic utility of pH monitoring and is the subject of the study discussed.
Kop, Willem J.; Weinstein, Ali A.; Deuster, Patricia A.; Whittaker, Kerry S.; Tracy, Russell P. (Nov 2008). Inflammatory markers and negative mood symptoms following exercise withdrawal. Brain Behavior, and Immunity, Vol 22(8), pp. 1190-1196.
Objective: Physical inactivity is associated with elevated inflammatory markers, but little is known about the time trajectories of reduced physical activity and inflammatory markers. Changes in inflammatory markers in response to withholding regular aerobic exercise were prospectively examined and correlated with increased negative mood symptoms and fatigue that accompany exercise withdrawal. Methods: Participants with regular exercise habits (N = 40, mean age of 31.3 ± 7.5 years, 55% women) were randomized to aerobic exercise withdrawal or to continue regular exercise for 2 weeks. Protocol adherence was documented using ambulatory actigraphy. Inflammatory markers (interleukin-6, C-reactive protein, fibrinogen and soluble intercellular adhesion molecule-1) were assessed at weekly intervals. Negative mood was measured with the Profile of Mood States (POMS) and the Beck Depression Inventory (BDI), and fatigue with the Multidimensional Fatigue Inventory (MFI). Autonomic nervous system activity was examined using heart rate variability-based indices. Results: Changes in inflammatory markers did not differ between exercise withdrawal and control groups (multivariate p interaction = 0.25). Exercise withdrawal resulted in increased negative mood symptoms and fatigue from baseline to day 14 compared to controls (p ΔPOMS = 0.008, p ΔBDI = 0.002; p ΔMFI = 0.003), but these responses were not associated with changes in inflammatory markers (p-values > 0.10). Inflammatory markers were also not correlated with autonomic nervous system dysregulation (p-values > 0.10). Conclusion: Inflammatory markers were not increased following 2 weeks of exercise withdrawal. Negative mood symptoms and fatigue were not accounted for by changes in inflammatory markers. Compensatory feedback mechanisms may operate among healthy individuals to promote resilience from the effects of reduced exercise.
Krmar RT, Berg UB. (Oct 2008). Blood pressure control in hypertensive pediatric renal transplants: role of repeated ABPM following transplantation. Am J Hypertens. 21(10):1093-9.
BACKGROUND: Hypertension in pediatric renal transplants is a widespread condition associated with high mortality risk in early adult life. Ambulatory blood pressure monitoring (ABPM) was found to be superior to office blood pressure (BP) in identifying true hypertensive and responders to treatment. The aim of this study was to investigate the role of repeated ABPM, performed at yearly intervals following transplantation, in the assessment and decision-making processes of post-transplant hypertension. METHODS: Thirty-seven recipients (23 males; aged 10.5 +/- 4.3 years) who were followed for 4.3 +/- 2.2 years (range 2-9) after transplantation were eligible for analysis. The mean follow-up time between the baseline (1 year post-transplantation) and the most recent ABPM examination was 3.3 +/- 2.2 years (range 1-8). RESULTS: Throughout the follow-up period, antihypertensive therapy was either started or intensified in 27 recipients. These interventions were decided based on ABPM results obtained on 40 of 44 occasions. At last follow-up, 24 of 29 treated hypertensive recipients displayed controlled BP. This figure was significantly higher compared to our historical hypertensive control recipients in whom ABPM was applied for the first time in treatment at 6 +/- 3.3 years (range 2-15) after transplantation, while therapeutic decisions were driven by office BP measurements (95 % confidence interval (95% CI) for the difference between proportions (80.6-32 %) 36-60 %, P = 0.001). CONCLUSIONS: Our study shows that, in a population with high risk for hypertension, repeated ABPM may significantly help to improve BP control.
Lampert R, Bremner JD, Su S, Miller A, Lee F, Cheema F, Goldberg J, Vaccarino V. (Oct 2008). Decreased heart rate variability is associated with higher levels of inflammation in middle-aged men. Am Heart J. 156(4):759.e1-7.
BACKGROUND: Many traditional risk factors for coronary artery disease (CAD) are associated with altered autonomic function. Inflammation may provide a link between risk factors, autonomic dysfunction, and CAD. We examined the association between heart rate variability (HRV), a measure of autonomic function, and inflammation, measured by C-reactive protein (CRP) and interleukin-6 (IL-6). METHODS: We examined 264 middle-aged male twins free of symptomatic CAD. All underwent ambulatory electrocardiogram monitoring and 24-hour ultra low, very low, low, and high-frequency power were calculated using power spectral analysis. C-reactive protein and IL-6 were measured, and risk factors including age, smoking, hypertension, lipids, diabetes, body mass index (BMI), depression, and physical activity were assessed. RESULTS: Physical activity, BMI, high-density lipoprotein cholesterol, smoking, depression, and hypertension were directly associated with CRP and IL-6 and inversely associated with one or more HRV variables. There was a graded inverse relationship between all HRV parameters (except high frequency) and CRP and IL-6. After adjustment for age, BMI, activity, high-density lipoprotein, smoking, hypertension, depression, and diabetes, ultra low frequency and very low frequency remained significant predictors of CRP (P < .01). CONCLUSIONS: C-reactive protein is associated with decreased HRV, even after controlling for traditional CAD risk factors. Autonomic dysregulation leading to inflammation may represent one pathway through which traditional risk factors promote development of CAD.
Lauszus FF, Rosgaard A, Lousen T, Rasmussen OW, Klebe TM, Klebe JG. (Nov 2008). Night/day ratio as predictor of preeclampsia in normoalbuminuric, diabetic women: early signs of blood pressure disorders. Arch Gynecol Obstet. [Epub ahead of print]
PURPOSE: Day/night ratio from diurnal ambulatory blood pressure (AMBP) in pregnant women with type 1 diabetes mellitus (T1DM) and in non-diabetic women was evaluated for its association with preeclampsia, retinopathy, HbA1c, and birth weight. METHODS: One hundred and sixty-one women were recruited for AMBP performed with a Spacelab 90207 monitor. The pregnant women were 50 non-diabetic women and 111 T1DM women with normoalbuminuria and no hypertension. ANOVA, regression, and ROC curves analysis were applied. RESULTS: Women with simplex retinopathy had higher night/day ratio and lower birth weight than those without retinopathy. Women who developed preeclampsia had night/day ratio similar to those with simplex retinopathy. In first trimester they had higher blood pressure than those who did not develop preeclampsia. CONCLUSIONS: Simplex retinopathy and preeclampsia are associated with a reduced night/day ratio even with normal blood pressure but night/day ratio provides no better prediction of preeclampsia than the absolute values.
Lazarescu A, Sifrim D. (Dec 2008). Ambulatory Monitoring of GERD: Current Technology. Gastroenterol Clin North Am. 37(4):793-805.
Various techniques have been devised to diagnose, characterize, and classify gastroesophageal reflux (GER). Stationary techniques, such as fluoroscopy and scintigraphy, provide interesting anatomic and functional information related to GER but are not sensitive enough and are usually performed in nonphysiologic conditions. Ambulatory techniques for GER monitoring have been developed and used since 1974. The current available techniques include catheter and wireless pH-metry, Bilitec, and impedance-pH monitoring. Prolonged wireless pH monitoring can be useful to evaluate patients off and on proton pump inhibitor (PPI) treatment. Impedance-pH monitoring is being used increasingly in patients who have persistent symptoms on PPI therapy because it can establish an association between symptoms and weakly acidic or nonacid reflux. Bilitec is performed in patients suspected to have increased duodenogastroesophageal reflux (DGER). This article discusses the technical details, clinical indications, and applications of these diagnostic techniques.
Macfarlane DJ, Chan D, Chan KL, Ho EY, Lee CC. (Oct 2008). Using three objective criteria to examine pedometer guidelines for free-living individuals. Eur J Appl Physiol. 104(3):435-44.
The purpose was to examine in free-living individuals from a high-density city (1) the objectively determined physical activity levels across quartiles derived from pedometer step counts, (2) the pedometer steps day(-1) required to meet health-enhancing guidelines of accruing 30 min day(-1) of moderate physical activity and (3) the agreement between three objective criteria for the pedometer guidelines. Over 7 days 49 Hong Kong Chinese aged 15-55 years (n = 30 males) wore a polar heart rate monitor (HRM), an MTI and Tritrac accelerometer, plus a Yamax pedometer for >or=600 min day(-1). Participants averaged 9,839 +/- 3,088 steps day(-1), whilst accumulating 44.5 +/- 22.6, 43.1 +/- 21.7, and 24.7 +/- 19.3 min day(-1) of moderate physical activity by the Tritrac, MTI and HRM, respectively. Significant differences between quartiles of pedometer-determined activity were predominantly seen in the accelerometry data, especially during moderate and moderate-to-vigorous intensity activity (effect sizes >1.5 between upper and lower quartiles), but not seen in the HRM data. Using both criterion accelerometer datasets, a threshold of 8,000 steps day(-1) accurately categorized approximately 90% of those achieving, and approximately 80% of those not achieving, 30 min day(-1) of appropriate activity. They also produced a screening sensitivity of approximately 95% and a specificity of approximately 70%, which were considerably higher than those from the HRM data. Overall, the agreement between the three criterion measures suggests 8,000 steps day(-1) might be a valid screening tool as a proxy for classifying those meeting public health physical activity recommendations of 30 min day(-1) of moderate activity.
Marsden PA, Smith JA, Kelsall AA, Owen E, Naylor JR, Webster D, Sumner H, Alam U, McGuinness K, Woodcock AA. (Nov 2008). A comparison of objective and subjective measures of cough in asthma. J Allergy Clin Immunol. 122(5):903-7.
BACKGROUND: Cough is widely recognized as a key symptom in the diagnosis and the monitoring of asthma, but little is known about how best to assess cough in asthma. OBJECTIVE: To determine how objective cough rates correlate with subjective measures of cough in asthma. METHODS: We studied 56 subjects, median age 42.0 years (range, 28.5-71), 34 (60.7%) female, with asthma. Subjects performed cough reflex sensitivity testing (concentration of citric acid causing 2 and 5 coughs [C2 and C5]), 24-hour fully ambulatory cough recordings, subjectively scored the severity of their cough (visual analog scales and 0-5 score) and completed a cough-related quality of life questionnaire (Leicester Cough Questionnaire). Ambulatory cough recordings were manually counted and reported in cough seconds per hour (cs/h). RESULTS: The median time spent coughing was 2.6 cs/h (range, 0.0-14.2), with subjects spending more time coughing by day (median, 3.9 cs/h [0.0-18.5]) than by night (median, 0.3 cs/h [0.0-8.7]; P < .001). A weak inverse relationship was seen between day cough rates and log(10)C2 (r = -0.39; P = .03) but not log(10)C5 (r = -0.08; P = .65). Objective time spent coughing was also weak-moderately associated with subjective cough scores and visual analog scales, and most strongly correlated with cough-related quality of life (r = -0.54; P < .001). CONCLUSION: Subjective measures of cough and cough reflex sensitivity are poor surrogates for objective cough frequency in asthma. When designing studies to assess interventions for cough in asthma, we advocate a combination of both objective measures of cough and cough-related quality of life.
Mastrototaro J, Shin J, Marcus A, Sulur G; STAR 1 Clinical Trial Investigators. (Oct 2008). The accuracy and efficacy of real-time continuous glucose monitoring sensor in patients with type 1 diabetes. Diabetes Technol Ther. 10(5):385-90.
BACKGROUND: The accuracy and efficacy of the Medtronic Diabetes (Northridge, CA) Real-Time (RT)-Continuous Glucose Monitoring (CGM) sensor were analyzed in 72 subjects with type 1 diabetes. METHODS: This was a retrospective analysis of 60,050 temporally paired data points (sensor and glucose meter values) obtained during the course of an outpatient ambulatory study evaluating the efficacy of a sensor-augmented pump system in adults and adolescents. Subjects uploaded sensor values and self-monitoring blood glucose data to the CareLink Clinical Application (Medtronic Diabetes) via the Internet, every 2 weeks during the course of the study. RESULTS: The overall percentage of sensor readings within +/-20% or +/-30% agreement of reference glucose readings was 75.6% and 86.8%, respectively. The highest rate of agreement occurred in the 240-400 mg/dL range, where 79.9% of sensor readings were within +/-20% of meter values and 91.5% of sensor readings were within 30% of meter values. The mean absolute relative difference for all subjects was 15.8%, and the median absolute relative difference was 10.9%. The bias was -2.13 mg/dL. Paired glucose measurements from the RT-CGM and meter demonstrated that 95.9% of paired points in the overall subject population fell in zones A and B of the Clarke Error Grid. Consensus Error Grid Analysis established that 99.2% of paired data points were in zones A and B. CONCLUSIONS: This study reports the accuracy of a continuous glucose sensor with a large number of paired data points (60,050). RT-CGM is safe and well tolerated and provides readings that are in close agreement with glucose meter values.
McClellan CB, Schatz JC, Puffer E, Sanchez CE, Stancil MT, Roberts CW. (Nov 2008). Use of Handheld Wireless Technology for a Home-based Sickle Cell Pain Management Protocol. J Pediatr Psychol. [Epub ahead of print]
Purpose To evaluate use of a handheld electronic wireless device to implement a pain management protocol for participants with sickle cell disease (SCD). METHODS: Participants were 19 patients with SCD aged 9-20 who experienced vaso-occlusive pain. A single-session training on the use of cognitive-behavioral coping skills was followed by instruction on how to practice these skills and monitor daily pain experience using the device. Daily pain experience and practice of coping skills were collected for the 8-week intervention period using wireless technology. RESULTS: High rates of participation, daily diary completion and consumer satisfaction support the use of handheld wireless devices to implement this protocol. A comparison of the rates of self and device-recorded skills practice provides important information about the use of electronic monitoring for behavioral interventions. CONCLUSION: Wireless data transfer technology has significant potential to become a practical method to improve symptom monitoring and communication between patients and providers.
McCormick BP, Frey G, Lee CT, Chun S, Sibthorp J, Gajic T, Stamatovic-Gajic B, Maksimovich M. (Nov 2008). Predicting transitory mood from physical activity level among people with severe mental illness in two cultures. Int J Soc Psychiatry. 54(6):527-38.
BACKGROUND: Previous studies have indicated that physical activity (PA) is positively related to health-related quality of life and well-being among people with severe mental illness (SMI). Physical activity is broadly defined in this research as any skeletal muscle movement resulting in energy expenditure, including common daily activities such as housework and gardening, as well as walking for transportation and formal exercise. Although the physical health benefits of PA are well documented, evidence suggests that PA provides psychological benefits as well. AIMS: The purpose of this study was to identify if PA level was associated with transitory mood in the everyday lives of people with SMI across two cultures. METHODS: Subjects were drawn through mental health centres in Serbia (n = 12) and the USA (n = 11). Data were collected using both experience sampling methodology and accelerometry. Data were analyzed using hierarchical linear modelling. RESULTS: Subjects demonstrated low levels of PA, which did not differ significantly between groups. Hierarchical analysis indicated that PA remained significantly positively associated with mood after accounting for individual variation, and this was consistent across groups. CONCLUSIONS: This study reinforces previous findings that people with SMI demonstrate low PA levels generally. It also supports the consideration of physical activity interventions as a regular part of psychiatric rehabilitation. It appears that increased PA may have the potential to affect both physical health and mood among people with SMI.
McDermott MM, Ades PA, Dyer A, Guralnik JM, Kibbe M, Criqui MH. (Nov 2008). Corridor-based functional performance measures correlate better with physical activity during daily life than treadmill measures in persons with peripheral arterial disease. J Vasc Surg. 48(5):1231-7, 1237.e1.
OBJECTIVE: To compare associations of physical activity during daily life with treadmill walking performance and corridor-based functional performance measures in persons with lower extremity peripheral arterial disease (PAD). STUDY DESIGN: Cross-sectional. SUBJECTS: One hundred fifty-six men and women with PAD who completed baseline measurements and were randomized into the study to improve leg circulation (SILC) exercise clinical trial. MAIN OUTCOME MEASURES: Participants completed a Gardner-Skinner treadmill protocol. Corridor-based functional performance measures were the 6-minute walk, walking velocity over four meters at usual and fastest pace, and the short physical performance battery (SPPB) (0-12 scale, 12 = best). Physical activity during daily life was measured continuously over 7 days with a Caltrac (Muscle Dynamics Fitness Network, Inc, Torrence, Calif) accelerometer. RESULTS: Adjusting for age, gender, and race, higher levels of physical activity during daily life were associated with greater distance achieved in the 6-minute walk (P trend = .001), faster fast-paced four-meter walking velocity (P trend < .001), faster usual-paced four-meter walking speed (P trend = .027) and a higher SPPB (P trend = .005). The association of physical activity level with maximum treadmill walking distance did not reach statistical significance (P trend = .083). There were no associations of physical activity with treadmill distance to onset of leg symptoms (P trend = .795). CONCLUSION: Functional performance measures are more strongly associated with physical activity levels during daily life than treadmill walking measures.
Taylor RW, Murdoch L, Carter P, Gerrard DF, Williams SM, Taylor BJ. (Dec 2008). Longitudinal Study of Physical Activity and Inactivity in Preschoolers: The FLAME Study. Med Sci Sports Exerc. [Epub ahead of print]
PURPOSE: To investigate patterns of activity and inactivity in a birth cohort of children followed from 3 to 5 yr and to investigate whether changes in activity occurred over time. METHODS: Two hundred and forty-four children (44% female) were seen annually at 3, 4, and 5 yr. Physical activity and inactivity was measured by questionnaire (parent-proxy) and by Actical accelerometers for five consecutive days (24-h monitoring) each year in children and once in each parent for 7 d (69% with data). RESULTS: Retention of participants was high (92%). Viable accelerometry data were obtained for 76-85% of children at each age. Reliability estimates ranged from 0.80 (3 yr) to 0.84 (5 yr). Day of the week, season, sex, hours of childcare, or birth order did not affect daily average accelerometry counts (AAC) at any age. Parental activity correlated weakly with the child’s activity at 3 and 4 yr (r values = 0.17-0.28), but only the father’s activity remained a significant predictor of the child’s activity after adjustment for confounders. Children spent approximately 90 min.d in screen time (television, videos, DVD, and computers) with an additional 90 min in other sedentary activities (reading, drawing, and music). Physical activity was significantly reduced at 4 and 5 yr compared with 3 yr in both sexes, whether measured as AAC (24-h data, awake time only, weekend days, weekdays), time in moderate or vigorous activity, or from parental reports of activity. CONCLUSION: Levels of physical activity declined in boys and girls between the ages 3 and 4-5 yr, whether using objective measures or parental reports of activity.
Mifsud G, Duval K, Doucet E. (Nov 2008). Low body fat and high cardiorespiratory fitness at the onset of the freshmen year may not protect against weight gain. Br J Nutr. 14:1-7.
The purpose of this study was to examine the effects of pre-university adiposity and physical fitness on changes of body weight and adiposity during the freshmen year. Twenty-nine freshmen (sixteen females and thirteen males) completed the study. Body weight and composition (dual-energy X-ray absorptiometry), waist circumference (WC), energy intake (7 d food diary) and activity-related energy expenditure (accelerometry) were measured in September, December and at the end of March. Peak oxygen uptake (VO2peak) was assessed at baseline only. Significant increases in body weight (1.9 (sd 2.0) kg, P < 0.05), BMI (0.6 (sd 0.7) kg/m2, P < 0.05), WC (2.7 (sd 3.0) cm, P < 0.05) and % body fat (BF) (3.1 (sd 2.3) %, P < 0.01) were noted in males, especially over the course of the first semester. No significant changes were observed in females. Results from correlation analyses showed that, baseline %BF was negatively associated with changes in body weight (r – 0.53, P < 0.01) and %BF (r – 0.41, P < 0.05) over the academic year. Baseline %BF predicted 27 % (P < 0.05) of the change in weight. Alcohol intake explained 34 % (P < 0.01) and 17 % (P < 0.05) of the changes in WC and %BF, respectively. The change in body weight and %BF were also positively associated with baseline VO2peak (r 0.51, P < 0.01; r 0.48, P < 0.01, respectively) while dietary restraint was negatively related to the changes in %BF (r – 0.43, P < 0.05). In summary, lower pre-university adiposity, higher VO2peak and higher alcohol intake are associated with greater changes in adiposity and body weight during the freshmen year.
Moreira A, Delgado L, Haahtela T, Fonseca J, Moreira P, Lopes C, Mota J, Santos P, Rytilä P, Castel-Branco MG. (Oct 2008). Physical training does not increase allergic inflammation in asthmatic children. Eur Respir J. 32(6):1570-5.
The effects of a 3-month physical training programme on airway inflammation and clinical outcomes were studied in school-aged children with asthma. Subjects with persistent allergic asthma (aged 12.7+/-3.4 yrs; n = 34) were randomly allocated into training and control groups. Exercise consisted of twice-weekly 50-min sessions for 12 weeks. Inflammation was assessed by levels of exhaled nitric oxide, blood eosinophils, eosinophil cationic protein, C-reactive protein, and total and mite-specific immunoglobulin (Ig)E. Lung volumes and bronchial responsiveness to methacholine were determined. The Paediatric Asthma Quality of Life Questionnaire and Paediatric Asthma Caregiver’s Quality of Life Questionnaire were used to evaluate activity restrictions, symptoms and emotional stress. The efficacy of the training was assessed by accelerometry. Following the programme, the exercise group spent twice as much time as the controls undertaking moderate-to-vigorous activities. No differences in changes were seen between groups for asthma outcomes. However, total IgE decreased more in the exercise group, as did mite-specific IgE. Training did not increase inflammation in children with persistent asthma, and may have decreased both total and allergen-specific immunoglobulin E levels. It is concluded that there is no reason to discourage asthmatic children with controlled disease to exercise.
Muehlenkamp JJ, Engel SG, Wadeson A, Crosby RD, Wonderlich SA, Simonich H, Mitchell JE. (Oct 2008). Emotional states preceding and following acts of non-suicidal self-injury in bulimia nervosa patients. Behav Res Ther. [Epub ahead of print]
Bulimia nervosa and non-suicidal self-injury (NSSI) co-occur at high rates, and both have been conceptualized as maladaptive emotion regulation strategies. Treatments focusing on emotion regulation have been designed for both problem behaviors, yet, there exists very little research examining the temporal emotional states surrounding acts of NSSI. Using ecological momentary assessment (EMA) methodology, the current study examined the temporal association between positive and negative emotional states prior to and consequent to acts of NSSI within a subset of bulimia nervosa patients. Results indicate significant increases in negative affect, and decreases in positive affect, prior to an NSSI act. Post-NSSI, positive affect significantly increased while negative affect remained unchanged. The findings offer partial support for an emotion regulation paradigm to understanding NSSI within bulimic populations and implications for treatment are discussed.
Murphy SL, Strasburg DM, Lyden AK, Smith DM, Koliba JF, Dadabhoy DP, Wallis SM. (Oct 2008). Effects of activity strategy training on pain and physical activity in older adults with knee or hip osteoarthritis: a pilot study. Arthritis Rheum. 59(10):1480-7.
OBJECTIVE: To examine effects of activity strategy training (AST), a structured rehabilitation program taught by occupational therapists and designed to teach adaptive strategies for symptom control and engagement in physical activity (PA). METHODS: A randomized controlled pilot trial was conducted at 4 sites (3 senior housing facilities and 1 senior center) in southeastern, lower Michigan. Fifty-four older adults with hip or knee osteoarthritis (mean +/- SD age 75.3+/-7.1 years) participated. At each site, older adults were randomly assigned to 1 of 2 programs: exercise plus AST (Ex + AST) or exercise plus health education (Ex + Ed). The programs involved 8 sessions over 4 weeks with 2 followup sessions over a 6-month period, and were conducted concurrently within each site. Pain, total PA and PA intensity (measured objectively by actigraphy and subjectively by the Community Healthy Activities Model Program for Seniors questionnaire), arthritis self-efficacy, and physical function were assessed at baseline and posttest. RESULTS: At posttest, participants who received Ex + AST had significantly higher levels of objective peak PA (P=0.02) compared with participants who received Ex + Ed. Although not statistically significant, participants in Ex + AST tended to have larger pain decreases, increased total objective and subjective PA, and increased physical function. No effects were found for arthritis self-efficacy. CONCLUSION: Although participants were involved in identical exercise programs, participants who received AST tended to have larger increases in PA at posttest compared with participants who received health education. Future studies will be needed to examine larger samples and long-term effects of AST.
Myers MG, Valdivieso M, Kiss A. (Dec 2008). Optimum frequency of office blood pressure measurement using an automated sphygmomanometer. Blood Press Monit. 13(6):333-8.
OBJECTIVE: To determine the optimum interval between serial blood pressure measurements using an automated BpTRU sphygmomanometer. METHODS: Two groups of 200 patients each had automated office measurements taken using the BpTRU device at either 1-min or 2-min intervals from the start of one reading to the start of the next reading with a 24-h ambulatory blood pressure (ABP) recording being performed. Another series of 50 patients had BpTRU readings taken at 1-min and 2-min intervals before and after 24-h ABP monitoring. The difference between the mean awake ABP and the mean automated office BP readings were compared for recordings taken at 1-min versus 2-min intervals. RESULTS: In the between-patient comparison (n=400), mean awake ABP was similar to automated BP recordings in the examining room at either 1-min or 2-min intervals except for a slightly lower (-4 mmHg) diastolic BP with the 1-min interval (P<0.01 vs. ABP). In the within-patient comparison (n=50), there was no consistent difference between automated BP readings taken in the examining room at 1-min versus 2-min intervals. Overall, the mean automated BP values tended to be slightly lower than the mean awake ABP. CONCLUSION: Automated measurement of BP in the office setting with devices such as the BpTRU can be taken as frequently as every 1 min without affecting the accuracy of the reading. Small differences in BP between the 1 and 2-min settings and between the automated BpTRU and ABP readings were within accepted clinical standards for validation criteria.
Myers MG. (Oct 2008). Recent advances in automated blood pressure measurement. Curr Hypertens Rep. 10(5):355-8.
During the past 15 years, clinical outcome studies have consistently reported that home and 24-hour ambulatory blood pressure recordings provide a significantly better measure of cardiovascular risk than do manual blood pressure readings taken in the office or clinic. The advent of automated sphygmomanometers that record blood pressure with the patient alone in the examining room will be the next major change in our approach to recording blood pressure. These automated devices virtually eliminate the white coat response and their readings correlate significantly better with the ambulatory blood pressure compared with manual office blood pressure readings. The principal finding from recent research into automated blood pressure measurement is that the presence of an observer during the actual reading in itself provokes the white coat response.
Nakano H, Tanigawa T, Ohnishi Y, Uemori H, Senzaki K, Furukawa T, Nishima S. (Oct 2008). Validation of a single-channel airflow monitor for screening of sleep-disordered breathing. Eur Respir J. 32(4):1060-7.
A simple screening method for sleep-disordered breathing (SDB) is desirable for primary care practices. In the present study, a simple monitor, which utilises a new type of flow sensor and a novel algorithm, was prospectively validated. Home recording for 2 nights with the monitor only, followed by in-laboratory recording with the monitor together with polysomnography, were carried out in consecutive patients (n = 100) suspected of SDB. A subjective sleep log was also recorded. The signal was analysed using power spectral analysis, which yielded the flow respiratory disturbance index (flow-RDI). There was no recording failure at home. The reproducibility of the flow-RDI between the 2 nights at home was high (intraclass correlation coefficient = 0.92). The sensitivity and specificity of the in-laboratory flow-RDI to diagnose SDB were 0.96 and 0.82, 0.91 and 0.82, and 0.89 and 0.96, for apnoea/hypopnoea index (AHI) > or =5, > or =15 and > or =30 events x h(-1), respectively. The diagnostic ability in low-severity subgroups (female, normal weight, AHI <15 events x h(-1)) was almost comparable to that in the entire group. Excluding subjective waking time on the sleep log from the recording time had no significant effect on the flow-RDI. The single-channel monitor is considered feasible for ambulatory sleep disordered breathing monitoring because of its easy applicability, high reproducibility and relatively high agreement with polysomnography results.
Ng CM, Yiu SF, Choi KL, Choi CH, Ng YW, Tiu SC. (Dec 2008). Prevalence and significance of white-coat hypertension and masked hypertension in type 2 diabetics. Hong Kong Med J. 14(6):437-43.
OBJECTIVES: To explore the prevalence of various categories of hypertension in diabetic patients, and assess any corresponding associations with end-organ complications. DESIGN: Cross-sectional study. SETTING: Tertiary centre of a regional hospital in Hong Kong. PATIENTS: All ambulatory type 2 diabetic patients attending our clinics from January 2002 to November 2004 were invited to participate in the protocol. RESULTS: A total of 133 diabetic patients were included; 82 had normal clinic blood pressures, 15 (18%) of whom had masked hypertension, the remaining 67 (82%) had ‘normotension’. The remaining 51 patients had high clinic blood pressures, of whom 28 (55%) had white-coat hypertension and 23 (45%) had sustained hypertension. Urinary albumin excretion rate was higher in patients with masked hypertension (10 mg/day; range, 7-580 mg/day) and sustained hypertension (7 mg/day; 7-3360 mg/day) in comparison to those with white-coat hypertension (7 mg/day; 7-109 mg/day) or ‘normotension’ (7 mg/day; 7-181 mg/day) [P<0.01]. Likewise, the prevalence of albuminuria was significantly higher in patients with masked hypertension (40%) and sustained hypertension (26%) than in those with ‘normotension’ (6%) and white-coat hypertension (11%) [P<0.01]. The prevalence of left ventricular hypertrophy was significantly higher in subjects with masked hypertension (38%) and sustained hypertension (26%) compared to patients with ‘normotension’ (8%) or white-coat hypertension (11%) [P<0.01]. Left ventricular diastolic dysfunction was more prevalent in patients with masked hypertension (46%), sustained hypertension (48%), and white-coat hypertension (43%) in comparison to subjects with ‘normotension’ (18%) [P=0.01]. CONCLUSION: Masked hypertension is associated with a higher prevalence of albuminuria, left ventricular diastolic dysfunction, and hypertrophy. White-coat hypertension carries a more benign prognosis than sustained hypertension and masked hypertension. Our cross-sectional study supports the recommendation to performing ambulatory blood pressure measurements in type 2 diabetic patients.
O’Connell , Kathleen A.; Schwartz, Joseph E.; Shiffman, Saul (Dec 2008). Do resisted temptations during smoking cessation deplete or augment self-control resources? Psychology of Addictive Behaviors, Vol 22(4), pp. 486-495.
A resource depletion model of self-control posits that for some period following performance of a task requiring self-control, self-control will be reduced and thus less available for use in a subsequent task. Using 2 substantial data sets collected in real time from individuals who were trying to quit smoking (1,660 and 9,516 temptation episodes collected from 61 and 248 individuals, respectively), we evaluated this model by testing the hypotheses that the number and length of resisted temptations and the intensity of the most recently reported urge during the prior 4 hr predict decreased self-control and increased likelihood of lapsing. Survival and multilevel regression modeling showed that contrary to the hypothesis, the number of recently resisted temptations predicted a lower risk of lapsing in both samples. Duration of resisted temptations had no significant effect in either sample. Intensity of most recently reported urge predicted lapsing in 1 data set but not in the other. Overall, there was little support for the resource depletion model. The protective effect of successfully resisting temptations was an unexpected but provocative finding.
Ogedegbe G, Pickering TG, Clemow L, Chaplin W, Spruill TM, Albanese GM, Eguchi K, Burg M, Gerin W. (Dec 2008). The misdiagnosis of hypertension: the role of patient anxiety. Arch Intern Med. 168(22):2459-65.
BACKGROUND: The white coat effect (defined as the difference between blood pressure [BP] measurements taken at the physician’s office and those taken outside the office) is an important determinant of misdiagnosis of hypertension, but little is known about the mechanisms underlying this phenomenon. We tested the hypothesis that the white coat effect may be a conditioned response as opposed to a manifestation of general anxiety. METHODS: A total of 238 patients in a hypertension clinic wore ambulatory blood pressure monitors on 3 separate days 1 month apart. At each clinic visit, BP readings were manually triggered in the waiting area and the examination room (in the presence and absence of the physician) and were compared with the mercury sphygmomanometer readings taken by the physician in the examination room. Patients completed trait and state anxiety measures before and after each BP assessment. RESULTS: A total of 35% of the sample was normotensive, and 9%, 37%, and 19% had white coat, sustained, and masked hypertension, respectively. The diagnostic category was associated with the state anxiety measure (F(3,237) = 6.4, P < .001) but not with the trait anxiety measure. Patients with white coat hypertension had significantly higher state anxiety scores (t = 2.67, P < .01), with the greatest difference reported during the physician measurement. The same pattern was observed for BP changes, which generally paralleled the changes in state anxiety (t = 4.86, P < .002 for systolic BP; t = 3.51, P < .002 for diastolic BP). CONCLUSIONS: These findings support our hypothesis that the white coat effect is a conditioned response. The BP measurements taken by physicians appear to exacerbate the white coat effect more than other means. This problem could be addressed with uniform use of automated BP devices in office settings.
Ohira T, Tanigawa T, Tabata M, Imano H, Kitamura A, Kiyama M, Sato S, Okamura T, Cui R, Koike KA, Shimamoto T, Iso H. (Nov 2008). Effects of habitual alcohol intake on ambulatory blood pressure, heart rate, and its variability among Japanese men. Hypertension. [Epub ahead of print]
We sought to examine effects of habitual alcohol intake on ambulatory blood pressure (BP), heart rate (HR), and HR variability among Japanese men. Subjects were 539 men aged 35 to 65 years from rural and urban communities. Ambulatory BP and HR were monitored with an automated, portable, noninvasive multibiomedical recorder. Power spectral analysis of the RR intervals on the ECG was performed every 5 minutes. Compared with nondrinkers, moderate drinkers (alcohol intake 23 to 45 g/d) and heavy drinkers (alcohol intake >or=46 g/d) showed higher age- and field-adjusted mean values of systolic and diastolic BPs during the morning and while awake, but there were no differences in BPs over 24-hour periods and while asleep among the alcohol intake categories. Alcohol intake was positively associated with mean values of sleep-morning differences and daytime variability in BPs, HRs while awake and asleep, and low frequency:high frequency ratio while asleep. The results were virtually unchanged after adjustment for body mass index, smoking, and diabetes mellitus. Compared with the nondrinkers, age- and field-adjusted odds ratios of the morning BP surge (excess elevation of BP in the morning: morning systolic BP minus sleep systolic BP >or=37 mm Hg) for light (alcohol intake 0 to 22 g/d), moderate, and heavy drinkers were 0.96 (95% CI: 0.34 to 2.78), 1.68 (95% CI: 0.64 to 4.38), and 2.73 (95% CI: 1.12 to 6.67), respectively. Habitual alcohol intake was associated with increased BP in the morning, HR while awake and asleep, and sympathetic activity while asleep, which may explain some of the mechanisms of the relationship between heavy alcohol intake and risk of cardiovascular diseases.
Osse RJ, Tulen JH, Bogers AJ, Hengeveld MW. (Dec 2008).Disturbed circadian motor activity patterns in postcardiotomy delirium. Psychiatry Clin Neurosci. [Epub ahead of print]
Aims: More than 20% of patients of 65 years or older may develop a delirium after cardiac surgery. Patients with delirium frequently show a disturbed 24-hr motor activity pattern, but objective and quantitative data are scarce. Our aim was to quantify motor activity patterns in elderly patients with or without a postcardiotomy delirium after elective cardiac surgery. Methods: Wrist-actigraphy was used to quantify 24-hr motor activity patterns for a 5-day period following cardiac surgery in 79 patients of 65 years or older. Clinical state was monitored daily by means of the Confusion Assessment Method-Intensive Care Unit and the Delirium Rating Scale-Revised 98. Results: The activity Amplitude, and the daytime Activity/minute and Restlessness index were significantly higher and the daytime number of Immobility minutes significantly lower for the patients without delirium or with short delirium episodes, as compared to patients with a sustained delirium (>3 days). Conclusions: Actigraphy proves to be a valuable instrument for evaluating motor activity patterns in relation to clinical state in patients with a postcardiotomy delirium.
Otsuki, Michiko; Tinsley, Barbara J.; Chao, Ruth K.; Unger, Jennifer B. (Dec 2008). An ecological perspective on smoking among Asian American college students: The roles of social smoking and smoking motives. Psychology of Addictive Behaviors, Vol 22(4), pp. 514-523.
Using electronic diaries, the present study examined the roles of social smoking and smoking motives in relation to cigarette use patterns among Asian American college smokers. Multilevel modeling results showed that participants smoked more cigarettes when smoking with peers than when smoking alone. Participants’ coping (but not social) motives moderated the within-person associations between smoking with peers and the cigarettes smoked during a smoking episode. The findings support the utility of an ecological perspective in examining the dynamic interaction between smoking motives and the social settings of cigarette use, and call for further research on the social smoking behaviors in diverse populations.
Parrish, Brendt P.; Zautra, Alex J.; Davis, Mary C. (Nov 2008). The role of positive and negative interpersonal events on daily fatigue in women with fibromyalgia, rheumatoid arthritis, and osteoarthritis. Health Psychology, Vol 27(6), pp. 694-702.
Objective: The current study tested whether daily interpersonal events predicted fatigue from one day to the next among female chronic pain patients. Design: Self-reported fatigue, daily events, pain, sleep quality, depressive symptoms, and functional health across 30 days were assessed in women with rheumatoid arthritis (RA: n = 89), Osteoarthritis (OA: n = 76), and Fibromyalgia syndrome (FM: n = 90). Main Outcome Measures: Self-report fatigue measured on a 0 to 100 scale and fatigue affect from PANAS-X (Watson & Clark, 1994). Results: Multilevel analyses showed that both higher average levels of and daily increases in negative events predicted more fatigue, whereas daily increases in positive events predicted less fatigue. Across all pain conditions, increases in negative events continued to predict higher fatigue on the following day. Moreover, for participants with FM or RA, increases in positive events also predicted increased fatigue the following day. Daily increases in fatigue, in turn, predicted poorer functional health on both the same day and the next day. Conclusion: These results indicate that both on average and on a daily basis, interpersonal events influence levels of fatigue beyond common physical and psychological correlates of chronic pain and highlight differences between chronic pain groups.
Persaud N. (Dec 2008). How can I tell how I think till I see what I say? Conscious Cogn. 17(4):1375; discussion 1376-7.
Descriptive Experience Sampling is a clever method for determining the form of everyday thoughts. Results using this method show that people report that some of their thoughts are unsymbolic. Here I ask three questions: (1) Does this merely show that people know what they are thinking about but not what they are thinking? (2) Why do people have difficulty determining the form of their thoughts? (3) How does the act of reporting the form of thoughts affect the recall of those thoughts?
Pickering TG, Gerin W, Schwartz JE, Spruill TM, Davidson KW. (Dec 2008). Franz Volhard lecture: should doctors still measure blood pressure? The missing patients with masked hypertension. J Hypertens. 26(12):2259-67.
The traditional reliance on blood pressure (BP) measurement in the medical setting misses a significant number of individuals with masked hypertension, who have normal clinic BP but persistently high daytime BP when measured out of the office. We suggest that masked hypertension may be a precursor of clinically recognized sustained hypertension and is associated with increased cardiovascular risk compared with consistent normotension. We discuss factors that may contribute to clinic-daytime BP differences as well as the changing relationship between these two measures over time. Anxiety at the time of BP measurement and having been diagnosed as hypertensive appear to be two possible mechanisms. The identification of individuals with masked hypertension is of great clinical importance and requires out-of-office BP screening. Ambulatory BP monitoring is the best established technique for doing this, but home monitoring may be applicable in the future.
Pogue V, Rahman M, Lipkowitz M, Toto R, Miller E, Faulkner M, Rostand S, Hiremath L, Sika M, Kendrick C, Hu B, Greene T, Appel L, Phillips RA; for the African American Study of Kidney Disease and Hypertension Collaborative Research Group (Dec 2008). Disparate Estimates of Hypertension Control From Ambulatory and Clinic Blood Pressure Measurements in Hypertensive Kidney Disease. Hypertension. [Epub ahead of print]
Ambulatory blood pressure (ABP) monitoring provides unique information about day-night patterns of blood pressure (BP). The objectives of this article were to describe ABP patterns in African Americans with hypertensive kidney disease, to examine the joint distribution of clinic BP and ABP, and to determine associations of hypertensive target organ damage with clinic BP and ABP. This study is a cross-sectional analysis of baseline data from the African American Study of Kidney Disease Cohort Study. Masked hypertension was defined by elevated daytime (>or= 135/85 mm Hg) or elevated nighttime (>or= 120/70 mm Hg) ABP in those with controlled clinic BP (<140/90 mm Hg); nondipping was defined by a <or= 10% decrease in mean nighttime systolic BP; reverse dipping was defined by a higher nighttime than daytime systolic BP. Of the 617 participants (mean age: 60.2 years; 62% male; mean estimated glomerular filtration rate: 43.8 mL/min per 1.73 m(2)) with both clinic BP and ABP, 498 participants (80%) had a nondipping or reverse dipping profile. Of the 377 participants with controlled clinic BP (61%), 70% had masked hypertension. Compared with those with controlled clinic BP or white-coat hypertension, target organ damage (proteinuria and left ventricular hypertrophy) was more common in those with elevated nighttime BP, masked hypertension, or sustained hypertension. In conclusion, clinic BP provides an incomplete and potentially misleading assessment of the severity of hypertension in African Americans with hypertensive kidney disease, in large part because of increased nighttime BP. Whether lowering nighttime BP improves clinical outcomes is unknown but should be tested given the substantial burden of BP-related morbidity in this population.
Prince SA, Adamo KB, Hamel ME, Hardt J, Gorber SC, Tremblay M. (Nov 2008). A comparison of direct versus self-report measures for assessing physical activity in adults: a systematic review. Int J Behav Nutr Phys Act. 5:56.
ABSTRACT: BACKGROUND: Accurate assessment is required to assess current and changing physical activity levels, and to evaluate the effectiveness of interventions designed to increase activity levels. This study systematically reviewed the literature to determine the extent of agreement between subjectively (self-report e.g. questionnaire, diary) and objectively (directly measured; e.g. accelerometry, doubly labeled water) assessed physical activity in adults. METHODS: Eight electronic databases were searched to identify observational and experimental studies of adult populations. Searching identified 4,463 potential articles. Initial screening found that 293 examined the relationship between self-reported and directly measured physical activity and met the eligibility criteria. Data abstraction was completed for 187 articles, which described comparable data and/or comparisons, while 76 articles lacked comparable data or comparisons, and a further 30 did not meet the review’s eligibility requirements. A risk of bias assessment was conducted for all articles from which data was abstracted. RESULTS: Correlations between self-report and direct measures were generally low-to-moderate and ranged from -0.71 to 0.96. No clear pattern emerged for the mean differences between self-report and direct measures of physical activity. Trends differed by measure of physical activity employed, level of physical activity measured, and the gender of participants. Results of the risk of bias assessment indicated that 38% of the studies had lower quality scores. CONCLUSION: The findings suggest that the measurement method may have a significant impact on the observed levels of physical activity. Self-report measures of physical activity were both higher and lower than directly measured levels of physical activity, which poses a problem for both reliance on self-report measures and for attempts to correct for self-report – direct measure differences. This review reveals the need for valid, accurate and reliable measures of physical activity in evaluating current and changing physical activity levels, physical activity interventions, and the relationships between physical activity and health outcomes.
Probst-Hensch NM, Imboden M, Felber Dietrich D, Barthélemy JC, Ackermann-Liebrich U, Berger W, Gaspoz JM, Schwartz J. (Nov 2008). Glutathione S-transferase polymorphisms, passive smoking, obesity, and heart rate variability in nonsmokers. Environ Health Perspect. 116(11):1494-9.
BACKGROUND: Disturbances of heart rate variability (HRV) may represent one pathway by which second-hand smoke (SHS) and air pollutants affect cardiovascular morbidity and mortality. The mechanisms are poorly understood. OBJECTIVES: We investigated the hypothesis that oxidative stress alters cardiac autonomic control. We studied the association of polymorphisms in oxidant-scavenging glutathione S-transferase (GST) genes and their interactions with SHS and obesity with HRV. METHODS: A total of 1,133 nonsmokers > 50 years of age from a population-based Swiss cohort underwent ambulatory 24-hr electrocardiogram monitoring and reported on lifestyle and medical history. We genotyped GSTM1 and GSTT1 gene deletions and a GSTP1 (Ile105Val) single nucleotide polymorphism and analyzed genotype-HRV associations by multiple linear regressions. RESULTS: Homozygous GSTT1 null genotypes exhibited an average 10% decrease in total power (TP) and low-frequency-domain HRV parameters. All three polymorphisms modified the cross-sectional associations of HRV with SHS and obesity. Homozygous GSTM1 null genotypes with > 2 hr/day of SHS exposure exhibited a 26% lower TP [95% confidence interval (CI), 11 to 39%], versus a reduction of -5% (95% CI, -22 to 17%) in subjects with the gene and the same SHS exposure compared with GSTM1 carriers without SHS exposure. Similarly, obese GSTM1 null genotypes had, on average, a 22% (95% CI, 12 to 31%) lower TP, whereas with the gene present obesity was associated with only a 3% decline (95% CI, -15% to 10%) compared with nonobese GSTM1 carriers. CONCLUSIONS: GST deficiency is associated with significant HRV alterations in the general population. Its interaction with SHS and obesity in reducing HRV is consistent with an impact of oxidative stress on the autonomous nervous system.
Pruitt LA, Glynn NW, King AC, Guralnik JM, Aiken EK, Miller G, Haskell WL. (Oct 2008). Use of accelerometry to measure physical activity in older adults at risk for mobility disability. J Aging Phys Act. 16(4):416-34.
The authors explored using the ActiGraph accelerometer to differentiate activity levels between participants in a physical activity (PA, n = 54) or “successful aging” (SA) program (n = 52). The relationship between a PA questionnaire for older adults (CHAMPS) and accelerometry variables was also determined. Individualized accelerometry-count thresholds (ThreshIND) measured during a 400-m walk were used to identify “meaningful activity.” Participants then wore the ActiGraph for 7 days. Results indicated more activity bouts/day > or =10 min above ThreshIND in the PA group than in the SA group (1.1 +/- 2.0 vs 0.5 +/- 0.8, p = .05) and more activity counts/day above ThreshIND for the PA group (28,101 +/- 27,521) than for the SA group (17,234 +/- 15,620, p = .02). Correlations between activity counts/hr and CHAMPS ranged from .27 to .42, p < .01. The ActiGraph and ThreshIND might be useful for differentiating PA levels in older adults at risk for mobility disability.
Quittner AL, Modi AC, Lemanek KL, Ievers-Landis CE, Rapoff MA. (Oct 2008). Evidence-based assessment of adherence to medical treatments in pediatric psychology. J Pediatr Psychol. 33(9):916-36; discussion 937-8.
OBJECTIVES: Adherence to medical regimens for children and adolescents with chronic conditions is generally below 50% and is considered the single, greatest cause of treatment failure. As the prevalence of chronic illnesses in pediatric populations increases and awareness of the negative consequences of poor adherence become clearer, the need for reliable and valid measures of adherence has grown. METHODS: This review evaluated empirical evidence for 18 measures utilizing three assessment methods: (a) self-report or structured interviews, (b) daily diary methods, and (c) electronic monitors. RESULTS: Ten measures met the “well-established” evidence-based (EBA) criteria. CONCLUSIONS: Several recommendations for improving adherence assessment were made. In particular, consideration should be given to the use of innovative technologies that provide a window into the “real time” behaviors of patients and families. Providing written treatment plans, identifying barriers to good adherence, and examining racial and ethnic differences in attitudes, beliefs and behaviors affecting adherence were strongly recommended.
Ralston JD, Hirsch IB, Hoath J, Mullen M, Allen C, Goldberg HI. (Nov 2008). Web-based Collaborative Care for Type 2 Diabetes: a Pilot Randomized Trial. Diabetes Care. [Epub ahead of print]
Objective: To test Web-based care management of glycemic control using a shared electronic medical record with patients who have type 2 diabetes. Research Design and Methods: A trial of 83 adults with type 2 diabetes randomized to receive usual care plus Web-based care management or usual care alone between August 2002 and May 2004. All patients had a glycohemoglobin (GHb) >/=7.0%, Web access from home, and could use a computer in English. Intervention patients received 12 months of Web-based care management. The Web-based program included patient access to electronic medical records, secure e-mail with providers, feedback on blood glucose readings, an educational Web site, and an interactive online diary for entering exercise, diet, and medication. Primary outcome was change in GHb. Results: GHb levels declined by 0.7% (95% CI: 0.2 -1.3) on average among intervention patients compared to usual care patients. Systolic blood pressure, diastolic blood pressure, total cholesterol levels Use of in-person health care services did not differ between the two groups. Conclusions: Care management delivered through secure patient Web communications improved glycemic control in type 2 diabetes.
Reiterer V, Sauter C, Klösch G, Lalouschek W, Zeitlhofer J. (Nov 2008). Actigraphy–a useful tool for motor activity monitoring in stroke patients. Eur Neurol. 60(6):285-91.
AIM: The aim of the present study was the evaluation of actigraphy as a tool to objectify the recovery process after motor paresis due to stroke. METHODS: The motor activity of both arms of patients suffering from stroke was actigraphically recorded at four different time points during the course of rehabilitation: 24-36 h, 5-7 days, 3 months, and 6 months after stroke. RESULTS: Motor activity monitored by wrist-worn actigraphs located at the impaired side revealed an increase in activity between the first two time points and the subsequent ones. Additionally, actigraphic recordings showed lower total motor activity at the impaired side as compared to the nonimpaired side. A significant positive correlation was found between the actigraphically recorded motor activity and the results of the Scandinavian Stroke scale, the Barthel Index, the Rankin Scale Score and with the Motoricity Index during the 1st week, which corresponds to the time when neurological deficits were most pronounced. CONCLUSION: Our results suggest that actigraphy is a useful tool in the objective evaluation of motor activity after stroke. Moreover, actigraphy covers additional aspects that are not reflected by the usual stroke scales in a clinical situation.
Rothney MP, Apker GA, Song Y, Chen KY. (Oct 2008). Comparing the performance of three generations of ActiGraph accelerometers. J Appl Physiol. 105(4):1091-7.
ActiGraph accelerometers are a useful tool for objective assessment of physical activity in clinical and epidemiological studies. Several generations of ActiGraph are being used; however, little work has been done to verify that measurements are consistent across generations. This study employed mechanical oscillations to characterize the dynamic response and intermonitor variability of three generations of ActiGraph monitors, from the oldest 7164 (n = 13), 71256 (n = 12), to the newest GT1M (n = 12). The response due to independent radius (22.1-60.4 mm) and frequency (25-250 rpm) changes were measured, as well as intermonitor variability within each generation. The 7164 and 71256 have similar relationships between activity counts and radius (P = 0.229) but were significantly different from the GT1M (P < 0.001). The frequency responses were nonlinear in all three generations. Although the response curve shapes were similar, the differences between generations at various frequencies were significant (P < 0.017), especially in the extremes of the measurement range. Intermonitor variability was markedly reduced in the GT1M compared with the 7164 and 71256. Other measurement differences between generations include decreased peak counts and decreased sensitivity in low-frequency detection in the GT1M. The results of this study revealed an improvement of the intermonitor variability by the GT1M monitor. However, the reduced sensitivity in low-count ranges in the GT1M may not be well suited for monitoring sedentary or light-intensity movements. Furthermore, the algorithms for energy expenditure predictions developed using older 7164 monitors may need to be modified for the GT1M.
Ruslami R, van Crevel R, van de Berge E, Alisjahbana B, Aarnoutse RE. (Nov 2008). A step-wise approach to find a valid and feasible method to detect non-adherence to tuberculosis drugs. Southeast Asian J Trop Med Public Health. 39(6):1083-7.
A step-wise approach to identify valid and feasible methods to detect non-adherence to tuberculosis drugs was evaluated in a prospective study among pulmonary tuberculosis patients in an outpatient clinic in Indonesia. First, adherence was measured by self-reporting with the standardized Morisky questionnaire, physician assessment, pill-count, visit attendance, diary and an electronic medication event monitoring system (MEMS). Next, validity of single methods was assessed against MEMS as gold standard. Feasibility of methods was then judged by physicians in the field. Finally, when valid and feasible methods were combined, it appeared that self-reporting by a questionnaire plus physician assessment could identify all non-adherent patients. It is recommended to use a systematic approach to develop a valid and locally feasible combination of methods to detect non-adherence to TB drugs.
Sakamoto N, Yoshiuchi K, Kikuchi H, Takimoto Y, Kaiya H, Kumano H, Yamamoto Y, Akabayashi A. (Nov 2008). Panic disorder and locomotor activity. Biopsychosoc Med. 2:23.
BACKGROUND: Panic disorder is one of the anxiety disorders, and anxiety is associated with some locomotor activity changes such as “restlessness”. However, there have been few studies on locomotor activity in panic disorder using actigraphy, although many studies on other psychiatric disorders have been reported using actigraphy. Therefore, the aim of the present study was to investigate the relationship between panic disorder and locomotor activity pattern using a wrist-worn activity monitor. In addition, an ecological momentary assessment technique was used to record panic attacks in natural settings. METHODS: Sixteen patients with panic disorder were asked to wear a watch-type computer as an electronic diary for recording panic attacks for two weeks. In addition, locomotor activity was measured and recorded continuously in an accelerometer equipped in the watch-type computer. Locomotor activity data were analyzed using double cosinor analysis to calculate mesor and the amplitude and acrophase of each of the circadian rhythm and 12-hour harmonic component. Correlations between panic disorder symptoms and locomotor activity were investigated. RESULTS: There were significant positive correlations between the frequency of panic attacks and mesor calculated from double cosinor analysis of locomotor activity (r = 0.55) and between HAM-A scores and mesor calculated from double cosinor analysis of locomotor activity (r = 0.62). CONCLUSION: Panic disorder patients with more panic attacks and more anxiety have greater objectively assessed locomotor activity, which may reflect the “restlessness” of anxiety disorders.
Salles GF, Cardoso CR, Muxfeldt ES. (Nov 2008). Prognostic influence of office and ambulatory blood pressures in resistant hypertension. Arch Intern Med. 168(21):2340-6.
BACKGROUND: The prognostic value of office and ambulatory blood pressures (BPs) in patients with resistant hypertension is uncertain. METHODS: This prospective study investigates the importance of office and ambulatory BPs as predictors of cardiovascular morbidity and mortality. At baseline, 556 resistant hypertensive patients underwent clinical-laboratory and 24-hour ambulatory BP monitoring examinations. Primary end points were a composite of fatal and nonfatal cardiovascular events and all-cause and cardiovascular mortalities. Multiple Cox regression was used to assess associations between BP and subsequent end points. RESULTS: After median follow-up of 4.8 years, 109 patients (19.6%) reached the primary end point, and 70 all-cause deaths (12.6%) occurred (46 had cardiovascular causes). After adjustment for age, sex, body mass index, diabetes mellitus, smoking, physical inactivity, dyslipidemia, previous cardiovascular diseases, serum creatinine level, and number of antihypertensive drugs in use, no office BP showed any prognostic value. After further adjustment for office BP, higher mean ambulatory BPs were independent predictors of the composite end point. The hazard ratios associated with a 1-SD increment in daytime and nighttime systolic BP were 1.26 (95% confidence interval, 1.04-1.53) and 1.38 (1.13-1.68), respectively; the corresponding values for diastolic BP were 1.31 (1.05-1.63) and 1.36 (1.10-1.69). Ambulatory systolic and diastolic BP were equivalent predictors, and both were better than pulse pressure; nighttime BP was superior to daytime BP. For all-cause mortality, only the ambulatory BP monitoring diagnosis of true resistant hypertension was an independent predictor. CONCLUSION: Higher ambulatory BP predicts cardiovascular morbidity and mortality in resistant hypertensive patients, whereas office BP has no prognostic value.
Sandland CJ, Morgan MD, Singh SJ. (Oct 2008). Patterns of domestic activity and ambulatory oxygen usage in COPD. Chest. 134(4):753-60.
BACKGROUND: The aim of this study was to examine patterns of domestic activity and ambulatory oxygen usage in patients with COPD in their domestic environment. METHODS: Twenty patients (14 men; mean age, 73.4 years [SD, 6.8 years]; FEV1, 1.0 L [SD, 0.5 L]) with stable COPD were recruited after completing a 7-week pulmonary rehabilitation program. Patients were either hypoxic at rest or had desaturation during exercise. Patients were randomized to an 8-week, double-blind, placebo-controlled trial of cylinder oxygen vs cylinder air. Total domestic physical activity and health-related quality of life (HRQL) measures were recorded before and after intervention. RESULTS: There were no significant changes in domestic activity or HRQL measures after the intervention for either cylinder oxygen or cylinder air, except for a worsening of the Chronic Respiratory Questionnaire dyspnea domain on cylinder air. There was a significant increase in mean duration (minutes per day) of cylinder use (p < 0.05) between weeks 1 vs 7 and weeks 1 vs 8 for the oxygen group. However, when comparing the two groups together, there were no between-group differences in cylinder use or time spent outside the home. Over the 8 weeks the majority of patients were using the cylinders in the home rather than outside, however, the number of times patients reported using the cylinders outside the home increased over the 8 weeks for the oxygen group. CONCLUSION: In the short term, ambulatory oxygen therapy is not associated with improvements in physical activity, HRQL, or time spent away from home. However, the use of cylinder oxygen increased over the 8 weeks compared to cylinder air. Patients need time to learn how to use oxygen, and ambulatory oxygen appears to enhance activities rather than increase them.
Shiffman S, Ferguson SG. (Oct 2008). The effect of a nicotine patch on cigarette craving over the course of the day: results from two randomized clinical trials. Curr Med Res Opin. 24(10):2795-804.
OBJECTIVES: The objective of this analysis was to assess the efficacy of a 21 mg/24-h nicotine patch for the reduction of craving throughout the waking day, compared both to placebo, and to a 15 mg/16-h patch differing pharmacokinetic profile over the day. The primary end-point was craving during the evening hours, because previous research suggested that smoking relapse was particularly likely at that time. RESEARCH DESIGN AND METHODS: Data were drawn from two similar randomized clinical trials among nicotine-dependent smokers who were quitting smoking: Study 1 compared the 21 mg/24-h patch to a placebo patch, while Study 2 compared the 21 mg/24-h patch to a 15 mg/16-h nicotine patch. In both studies, subjects (Study 1: n = 102; Study 2: n = 244) were prompted by an electronic diary to rate their craving multiple times per day during a 1 week baseline period, and for up to 2 weeks after quitting. For analysis, the day was divided into five blocks: morning (up to 10:59 a.m.), mid-day (11:00 a.m.-1:59 p.m.), afternoon (2:00 p.m.-4:59 p.m.), evening (5:00 p.m.-8:59 p.m.), and late night (9:00 p.m. onwards). The individual craving ratings were divided into three intervals based on time since quitting: Days 1-3, 4-7, and 8-14. RESULTS: The 21 mg/24-h nicotine patch resulted in significantly lower craving during all post-quit intervals, at each time of day, both compared to placebo (Study 1), and compared to the 15 mg/16-h nicotine patch (Study 2). Study 2 saw a significant treatment by interval interaction: in later time intervals, the difference in craving experience between 24- and 16-h patch conditions shrunk–while remaining significantly different–as overall levels of craving experienced by subjects in the two groups dropped. Adverse events reported in both studies tended to be mild and transient, consistent with the well characterized adverse event profile of nicotine patches. CONCLUSIONS: Study 1 demonstrated that a 21 mg/24-h patch was effective in reducing craving throughout the day, including the evening period when relapse risk is heightened. A further study comparing the 21 mg/24-h patch to a 15 mg/16-h nicotine patch found that craving was significantly lower at all times of day for smokers using the 21 mg/24-h patch. The studies were limited in that craving was only monitored for the first 2 weeks of quitting (when craving is most prominent), and cannot elucidate the impact of patch use on craving outside of this time. Also, there was substantial attrition of the sample over time, partly due to relapse in all conditions.
Silbermann A, Henkel A, Müller A, de Zwaan M. (Dec 2008). [The application of ecological momentary assessment to the study of compulsive buying] Psychother Psychosom Med Psychol. 58(12):454-61. German.
Although compulsive buying is a disorder that has begun to receive attention from researchers in recent years, relatively little is known about the relationship between compulsive buying, mood, and daily stressful events. In our pilot study ecological momentary assessment (EMA) was used to examine the described relationships for the first time. 26 patients, who met criteria for compulsive buying, self-monitored their pathological behaviour, their momentary mood and the occurrence of stressful events four times a day on a handheld computer for a period of two weeks. On days with excessive buying behaviour patients reported significantly more daily stressful events compared to days without pathological buying. Before the buying episode patients recorded significantly more positive emotions. The most common consequence of compulsive buying was a significant decrease of positive affects. Thus the results of the current study suggest that mood states and daily stressful events are associated with compulsive buying behaviour. Although mood got worse immediately after excessive buying, this negative consequence did not reduce the frequency of pathological behaviour. This could implicate a high presence-orientation and impulsivity of the patients.
Soylu A, Akif Duzenli M, Yazici M, Ozdemir K, Tokac M, Gok H. (Nov 2008). The Effect of Nondipping Blood Pressure Patterns on Cardiac Structural Changes and Left Ventricular Diastolic Functions in Normotensives. Echocardiography. [Epub ahead of print]
Background: Cardiac structural changes have been reported to be more prominent in nondipper normotensives than the dipper ones. But the influence of nondipping status on cardiac diastolic functions of normotensives has not been studied yet. In this study, we investigated the effect of nondipping status on both cardiac structural changes and left ventricular (LV) diastolic functions in normotensives. Methods: We performed ambulatory blood pressure (BP) monitoring (ABPM) and echocardiography in 62 normotensive subjects with the following criteria: (1) office BP < 140/90 mmHg; (2) average 24-hour ambulatory BP < 130/80 mmHg. Results: In the evaluation by tissue Doppler imaging (TDI), the early diastolic myocardial peak velocity (Em) and Em/late diastolic myocardial peak velocity (Am) ratio (Em/Am ratio) were lower in nondippers than those in dippers (P = 0.009 and P < 0.001, respectively). Isovolumic relaxation time (IRT) and myocardial performance index (MPI) were higher in nondippers than those in dippers (P = 0.036 and P = 0.026, respectively). Nondipping status, independent of other factors, was observed to cause both a decrease in the Em and Em/Am ratio and an increase in IRT. However, its effect on IRT was not statistically significant (coefficient =-0.27, P = 0.027; coefficient =-0.37, P = 0.002; coefficient = 0.20, P = 0.082, respectively). Conclusions: Nondipping of nocturnal BP seems to be a determinant of cardiac remodeling and LV diastolic dysfunction (LVDD) and may result in a cardiovascular (CV) risk independent of the increase in LV mass (LVM) in normotensives.
Stergiou GS, Mastorantonakis SE, Roussias LG. (Oct 2008). Intraindividual reproducibility of blood pressure surge upon rising after nighttime sleep and siesta. Hypertens Res. 31(10):1859-64.
The surge in blood pressure (BP) upon rising after waking in the morning has been associated with increased risk of target organ damage and cardiovascular events. The reproducibility of this phenomenon within the same 24-h period was tested in subjects with a siesta during ambulatory BP monitoring by assessing the morning surge (MS) vs. the evening surge (ES) after siesta. Ambulatory BP recordings with reported siesta from hypertensive subjects were analyzed. MS and ES were assessed using four different definitions. The intraindividual reproducibility was assessed using the standard deviation of differences between MS and ES, the concordance correlation coefficient, the coefficient of variation and the agreement between MS and ES in detecting “surgers” among hypertensive subjects (top quartile of the BP surge distribution). A total of 562 ambulatory recordings were analyzed (476 subjects, mean age 54.9+/-13.2 [SD] years, treated 47%). Average MS (16.3/14.4 mmHg, systolic/diastolic) was higher than ES (13.3/12.1 mmHg, p<0.001) due to higher post-rising BP in the morning (p<0.01). The intraindividual reproducibility was rather poor, with no clear differences among different definitions. However, there was about 70% agreement between MS and ES in the detection of “surgers” (systolic and diastolic, kappa statistic 0.18). These data suggest that, although the intraindividual reproducibility of the BP surge within the same 24-h period is rather poor, about 70% of the “morning surgers” were also “evening surgers.” Thus, the BP surge might be an inherent pathophysiological characteristic of the BP behavior of an individual and deserves further investigation.
Swartz SJ, Srivaths PR, Croix B, Feig DI. (Dec 2008). Cost-effectiveness of ambulatory blood pressure monitoring in the initial evaluation of hypertension in children. Pediatrics. 122(6):1177-81.
OBJECTIVE: The goal was to determine the cost-effectiveness of ambulatory blood pressure monitoring in the initial evaluation of stage 1 hypertension. METHODS: Retrospective chart review of data for children referred to Texas Children’s Hospital hypertension clinic between January 2005 and August 2006 was performed. We compared the costs of standard evaluations versus the initial use of ambulatory blood pressure monitoring for children with clinic blood pressure measurements suggesting stage 1 hypertension. Charges for clinic visits, laboratory tests, and imaging were obtained from the Texas Children’s Hospital billing department. RESULTS: A total of 267 children were referred. One hundred thirty-nine children did not receive ambulatory blood pressure monitoring; 54 met clinical indications for ambulatory blood pressure monitoring but did not receive it because it was not a covered expense (44 children) or the family refused the study (10 children). One hundred twenty-six children received clinically indicated ambulatory blood pressure monitoring, paid for either through insurance or by the family. Fifty-eight children (46%) had confirmed white-coat hypertension, 62 (49%) stage 1 hypertension, and 6 (5%) stage 2 hypertension. With the observed prevalence of white-coat hypertension, initial ambulatory blood pressure monitoring use yielded net savings after evaluation of 3 patients, with projected savings of $2.4 million per 1000 patients. CONCLUSIONS: Ambulatory blood pressure monitoring in the initial evaluation of suspected childhood hypertension is highly cost-effective. Awareness of cost saving potential may increase the availability of ambulatory blood pressure monitoring for evaluation of new-onset hypertension.
Thalenberg JM, Póvoa RM, Bombig MT, de Sá GA, Atallah AN, Luna Filho B. (Oct 2008). Slow breathing test increases the suspicion of white-coat hypertension in the office. Arq Bras Cardiol. 91(4):243-9, 267-73.
BACKGROUND: It would be useful to have a clinical test that increases the suspicion of white coat hypertension (WCH) during the medical consultation. OBJECTIVE: To evaluate the Slow Breathing Test (SBT) when differentiating hypertension from WCH. METHODS: 101 hypertensive patients selected at triage had their medication withdrawn for 2-3 weeks. The blood pressure (BP) was measured before and after the SBT at two consultations at the office. The test consisted in breathing for 1 minute at the frequency of one respiratory cycle every 10 seconds. Two diagnostic criteria were compared: 1–decrease in diastolic BP > or = 10% in at least one visit or 2–decrease in BP to normal levels (<140/90 mm Hg) in at least one visit. The ambulatory blood pressure monitoring (ABPM) was performed while blinded to the clinical measurements. RESULTS: 71 women and 30 men, with a mean age of 51+/-10 years, with mean pre and post-test BP of 152+/-17/ 99+/-11 and 140+/-18/ 91+/-11 mm Hg were assessed. Nine patients had normal clinical and ambulatory measurements. Of the 92 patients, 28 (30%) were classified as having WCH; 15 had a positive test for Criterion 1 and 21 for the Criterion 2. Among 64 (70%) hypertensive individuals, 14 tested positive for Criterion 1 and 12 for Criterion 2. Sensitivity and specificity (95% CI): 0.54 (0.36-0.71) and 0.78 (0.67-0.87) for Criterion 1; 0.75 (0.57-0.87) and 0.81 (0.70-0.89) for Criterion 2. CONCLUSION: The SBT showed an increase in the clinical suspicion of WCH in two visits when using the BP normalization criterion. This finding suggests that the test can help in the optimization of ABPM requests for suspected cases.
Thomas AS, Greene LF, Ard JD, Oster RA, Darnell BE, Gower BA. (Oct 2008). Physical Activity May Facilitate Diabetes Prevention in Adolescents. Diabetes Care. [Epub ahead of print]
OBJECTIVE: The aim of this study was to examine the association of physical activity with glucose tolerance and resting energy expenditure (REE) among adolescents. RESEARCH DESIGN AND METHODS: Subjects were 32 male and female adolescents aged 12-18 years. Intravenous glucose tolerance (K(g)) and REE were assessed under inpatient conditions after an overnight fast. K(g) was determined as the inverse slope of time versus (ln) glucose over minutes 8-19 of an intravenous glucose tolerance test. Physical activity was assessed over 8 days using accelerometry (counts per minute). RESULTS: In multiple linear regression analysis, K(g) was positively associated with total physical activity (TPA), moderate physical activity (MPA), and 5-min bouts of MPA. Similarly, REE was positively associated with TPA, MPA, and 5-min bouts of MPA. CONCLUSIONS: In this population, physical activity was positively related to both glucose tolerance and REE. These results suggest that moderate activity may be beneficial in the prevention of diabetes in adolescent populations both through promoting efficient glucose disposal and through increasing energy expenditure.
Tsukasaki K, Makimoto K, Kido T. (Dec 2008). The impact of sleep on ambulatory blood pressure of female caregivers providing home care in Japan: An observational study. Int J Nurs Stud. 45(12):1721-30.
BACKGROUND: Elderly family caregivers are presumed to be susceptible to having various health problems. However, biomedical indicators of health in these caregivers are rarely examined. OBJECTIVE: To examine the effect of sleep quality, measured by hours of sleep and the number of times leaving bed, on various blood pressure parameters in elderly caregivers. DESIGN: Observational study. SETTING: Northern Japan. PARTICIPANTS: Seventy-eight female family caregivers. METHODS: Ambulatory blood pressure was monitored at 30-60-min intervals for a 24-h period. An actigraph was used to determine sleep/wake status. Face-to-face interviews were conducted to obtain home care and demographic information, and self-administered questionnaires were used to collect information on activities in a 24-h period. RESULTS: The mean age of the caregivers was 62.5+/-9.6 years, and the mean hours of sleep were 7.3. Out of 78 caregivers, 19 were on antihypertensive medication. Of the remaining 59, this study found 45.8% to be hypertensive, with the mean maximum systolic pressure exceeding 180mmHg. The hours of sleep at night and for the 24-h period were inversely associated with the mean systolic blood pressure. The majority of caregivers on antihypertensive medication also had high blood pressure. CONCLUSIONS: This study suggests the importance of 24-h ambulatory blood pressure monitoring for elderly caregivers, so as to screen for hypertension as well as to monitor the effectiveness of antihypertensive medication.
van den Berg-Emons RJ, Bussmann JB, Haisma JA, Sluis TA, van der Woude LH, Bergen MP, Stam HJ. (Nov 2008). A prospective study on physical activity levels after spinal cord injury during inpatient rehabilitation and the year after discharge. Arch Phys Med Rehabil. 89(11):2094-101.
OBJECTIVES: To assess the change over time in the physical activity level after a spinal cord injury (SCI), to explore its determinants, and to compare the physical activity level 1 year after discharge from the rehabilitation center with the level in able-bodied persons. DESIGN: Prospective cohort study. Measurements were obtained at the start of active rehabilitation, 3 months later, at discharge, 2 months after discharge, and 1 year after discharge. SETTING: Rehabilitation center in The Netherlands and the participant’s home. PARTICIPANTS: Persons (n=40) with SCI. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The physical activity level, as indicated by the duration of dynamic activities (ie, wheelchair driving, walking, cycling, noncyclic movement) per day, and the intensity of everyday activity; both were measured with an accelerometry-based activity monitor during 2 consecutive weekdays. RESULTS: Random coefficient analyses showed that the duration of dynamic activities and the intensity of everyday activity increased during inpatient rehabilitation at rates of 41% and 19%, respectively (P<.01). Shortly after discharge, there was a strong decline (33%; P<.001) in the duration of dynamic activities. One year after discharge, this decline was restored to the discharge level but was low in comparison with levels in able-bodied persons. The level of lesion and completeness of lesion were determinants of the change in the physical activity level after discharge. CONCLUSIONS: The physical activity level increased during inpatient rehabilitation, but this increase did not continue after discharge, and the level 1 year after discharge was distinctly lower than the level in able-bodied persons. Subpopulations had a different change over time in the physical activity level after discharge.
van Hedel HJ, Dietz V; European Multicenter Study on Human Spinal Cord Injury (EM-SCI) Study Group. (Nov 2008). Walking During Daily Life Can Be Validly and Responsively Assessed in Subjects With a Spinal Cord Injury. Neurorehabil Neural Repair. [Epub ahead of print]
OBJECTIVE: . This study assessed the validity and responsiveness of the Spinal Cord Independence Measure (SCIM II) items indoor mobility, mobility for moderate distances, and outdoor mobility. METHODS: . The data of 886 spinal cord injury subjects were derived from the European Multicenter Study for Human Spinal Cord Injury (EM-SCI) and analyzed at 2 weeks and 1, 3, 6, and 12 months after injury. The SCIM II items were compared using the preferred walking speed and the Walking Index for Spinal Cord Injury (WISCI II). The responsiveness to assess differences over time was determined. The analyses were performed for subjects with varying impairment scales according to the American Spinal Injury Association (ASIA). RESULTS: . An initially moderate correlation between walking capacity and the SCIM II mobility items improved to excellent at 6 and 12 months after injury. The correlations were higher for indoor mobility compared with outdoor mobility. These correlations increased in ASIA C, but decreased over time in ASIA D subjects. The SCIM II mobility items showed initially positive responsiveness in ASIA A and B subjects. In ASIA C and D subjects, SCIM II responsiveness was significant within the first 6 months. CONCLUSIONS: . The SCIM II items assess mobility (wheelchair and walking) during daily life. They show good validity and responsiveness, including postdischarge. They can be considered appropriate for evaluating the efficacy of new interventions on ambulatory function. Depending on the severity of the initial lesion and time of assessment, clinically applied walking tests can accurately predict walking performance during daily life.
van Sluijs EM, Page A, Ommundsen Y, Griffin SJ. (2008). Behavioural and social correlates of sedentary time in young people. Br J Sports Med. [Epub ahead of print]
OBJECTIVE: To identify behavioural and social correlates of objectively-measured sedentary time in young people. DESIGN: Cross-sectional analysis of data from the European Youth Heart Study (EYHS). SETTING: Schools in Denmark, Estonia, Portugal and Norway. PARTICIPANTS: Invited using a two-stage cluster sampling procedure. Analyses include 2107 children (9-10 years) and adolescents (14-15 years). Assessment of independent variables: Seven behavioral and 15 social variables assessed by parental and computerized child questionnaires. MAIN OUTCOME MEASURE: Sedentary activity as assessed by accelerometry (10-minute blocks at <200 counts/minute). Analyses were stratified by country and interactions with grade and gender were investigated. RESULTS: Adolescents were more sedentary than children (335.4 (SD: 90.4) vs. 217.2 (SD: 75.6) minutes/day, p<0.001). Patterns of associations differed across countries. High computer use and no television viewing before school in Norway, and being sedentary during school-breaks in Estonia were positively associated with sedentary time. No behavioural variables were associated with sedentary time in the Danish and Portuguese models. Socioeconomic position was positively associated with sedentary time in Portugal and Estonia, father inverted exclamation mark|s body mass index negatively in the Estonian model. Norwegian participants with a games console at home and Portuguese participants with a television in their bedroom were more sedentary. CONCLUSIONS: A single strategy aimed at reducing sedentary behaviour is unlikely to be effective across Europe as the target populations and behaviours of focus differ between countries. Targeting high socioeconomic groups in Portugal and Estonia or focusing on reducing computer use in Norway might be effective intervention strategies to reduce overall sedentary time.
Van Zundert RM, Nijhof LM, Engels RC. (Nov 2008). Testing Social Cognitive Theory as a theoretical framework to predict smoking relapse among daily smoking adolescents. Addict Behav. [Epub ahead of print]
Predictors of adolescent smoking relapse are largely unknown, since studies either focus on relapse among adults, or address (long-term) smoking cessation but not relapse. In the present study, Social Cognitive Theory (SCT) was used as a theoretical framework to examine the first and second lapses, as well as mild and heavy relapse into smoking among 135 daily smoking adolescents who embarked on a serious quit attempt. Baseline predictors were pros of smoking, pros of quitting, self-efficacy, and intensity of smoking. Using an ecological momentary assessment (EMA) study design, participants were monitored three times a day during 4 weeks. A follow-up was administered 2 months after the monitoring period. Perceiving many pros of smoking, reporting a low self-efficacy to quit, and high levels of baseline smoking significantly predicted relapse within 3 weeks after quitting. The effects of pros of smoking and self-efficacy on relapse, however, appeared to be accounted for by differences in intensity of smoking. Besides that pros of quitting showed a marginal effect on abstinence at the 2-month follow-up, no long-term effects were detected.
Vazire, Simine; Mehl, Matthias R. (Nov 2008). Knowing me, knowing you: The accuracy and unique predictive validity of self-ratings and other-ratings of daily behavior. Journal of Personality and Social Psychology, Vol 95(5), pp. 1202-1216.
Many people assume that they know themselves better than anyone else knows them. Recent research on inaccuracies in self-perception, however, suggests that self-knowledge may be more limited than people typically assume. In this article, the authors examine the possibility that people may know a person as well as (or better than) that person knows himself or herself. In Study 1, the authors document the strength of laypeople’s beliefs that the self is the best expert. In Study 2, the authors provide a direct test of self- and other-accuracy using an objective and representative behavioral criterion. To do this, the authors compared self- and other-ratings of daily behavior to real-life measures of act frequencies assessed unobtrusively over 4 days. Our results show that close others are as accurate as the self in predicting daily behavior. Furthermore, accuracy varies across behaviors for both the self and for others, and the two perspectives often independently predict behavior. These findings suggest that there is no single perspective from which a person is known best and that both the self and others possess unique insight into how a person typically behaves.
Virtanen MP, Kööbi T, Turjanmaa VM, Majahalme S, Tuomisto MT, Nieminen T, Kähönen M. (Nov 2008). Predicting arterial stiffness with ambulatory blood pressure: an 11-year follow-up. Clin Physiol Funct Imaging. 28(6):378-83.
No prospective data have been published on whether ambulatory blood pressure (BP) works better than casual measurements in predicting arterial stiffness. This study with 11-year follow-up was launched to evaluate the usefulness of ambulatory intra-arterial BP in predicting pulse wave velocity (PWV). Ninety-seven previously healthy men were recruited from a routine physical check-up at baseline. BP was measured with standard cuff and intra-arterial ambulatory methods. Sixty-seven subjects with no antihypertensive medication were enrolled for a visit after a follow-up of 11 years. Arterial stiffness was estimated with PWV derived with impedance cardiography. Ambulatory 24-h systolic blood pressure (SBP) (r = 0.30, P = 0.01), 24-h mean arterial pressure (r = 0.27, P = 0.03), 24-h pulse pressure (r = 0.27, P = 0.03) and daytime SBP (r = 0.26, P = 0.03) were the best BP variables in predicting future PWV. Casual BP values did not bear significant correlations with future PWV. In hierarchical regression analysis, the best predictive value for future PWV was achieved with the model including ambulatory 24-h SBP, smoking (number of cigarettes) and age (adjusted R(2) = 0.26). In conclusion, to our knowledge, this is the only prospective follow-up study to show that ambulatory BP is superior to casual BP measurement in predicting future PWV.
Vyssoulis G, Karpanou E, Adamopoulos D, Kyvelou SM, Gymnopoulou E, Cokkinos D, Stefanadis C. (Oct 2008). Nocturnal blood pressure fall and metabolic syndrome score in patients with white coat hypertension. Blood Press Monit. 13(5):251-6.
BACKGROUND: Accumulating data report that white coat hypertension (WCH) is associated with target organ damage. Metabolic syndrome (MS), and nondipping pattern is also associated with increased cardiovascular risk. The purpose of this study was to explore the nocturnal blood pressure fall in WCH patients according to their MS score. METHODS: The study comprised 2300 patients with WCH who attended our outpatient clinics. All underwent repeated office blood pressure measurements, 24-h ambulatory blood pressure monitoring, full clinical and laboratory evaluation. The diagnosis of MS was made according to the Adult Treatment Panel III criteria and patients were classified into five groups: group I (hypertension), group II (hypertension and any one component), group III (hypertension and any two components), group IV (hypertension and any three components), and group V (all five components). Dipping pattern was defined as ‘dippers’ with nocturnal systolic blood pressure (NSBP) fall greater than or equal to 10% but less than 20%, ‘nondippers’ with NSBP fall greater than or equal to 0% but less than 10%, ‘extreme dippers’ with NSBP fall greater than or equal to 20%, and ‘reverse dippers’ with NSBP increase. RESULTS: Patients were divided into two groups according to the presence (n=522) and absence (n=1778) of MS. The overall prevalence of MS in the study population was 22.7%. Comparing the non-MS group with the MS we observed significant differences for nondippers (24.5% vs. 38.9%, P<0.001), dippers (54.4% vs. 43.5%, P<0.001), extreme dippers (17.8% vs. 11.3%, P<0.001), and reverse dippers (3.3% vs. 6.3%, P=0.007). CONCLUSION: Patients with WCH and increased number of MS components present with elevated nighttime SBP levels. This observation is of a great significance in the assessment of the cardiovascular risk in these patients.
Weinstein, Sally M.; Mermelstein, Robin; Shiffman, Saul; Flay, Brian (Dec 2008). Mood variability and cigarette smoking escalation among adolescents. Psychology of Addictive Behaviors, Vol 22(4), pp. 504-513.
The current study examined how affect dysregulation, as indexed via within-person negative mood variability, related to longitudinal patterns of smoking among adolescents. Students in the 8th and 10th grades (N = 517, 56% girls) provided data on cigarette use at baseline, 6-, and 12-month waves and provided ecological momentary assessments of negative moods via palmtop computers for 1 week at each wave. Mood variability was examined via the intraindividual standard deviations of negative mood reports at each wave. As predicted, high levels of negative mood variability at baseline significantly differentiated participants who escalated in their smoking behavior over time from participants who never progressed beyond low levels of experimentation during the course of the study. Mixed-effects regression models revealed that participants who escalated in their smoking experienced a reduction in mood variability as smoking increased, whereas participants with consistently high or low levels of cigarette use had more stable mood variability levels. Results suggest that high negative mood variability is a risk factor for future smoking escalation and that mood-stabilizing effects may reinforce and maintain daily cigarette use among youths.
Wichers M, Aguilera M, Kenis G, Krabbendam L, Myin-Germeys I, Jacobs N, Peeters F, Derom C, Vlietinck R, Mengelers R, Delespaul P, van Os J. (Dec 2008). The catechol-O-methyl transferase Val158Met polymorphism and experience of reward in the flow of daily life. Neuropsychopharmacology. 33(13):3030-6.
Genetic moderation of experience of reward in response to environmental stimuli is relevant for the study of many psychiatric disorders. Experience of reward, however, is difficult to capture, as it involves small fluctuations in affect in response to small events in the flow of daily life. This study examined a momentary assessment reward phenotype in relation to the catechol-O-methyl transferase (COMT) Val(158)Met polymorphism. A total of 351 participants from a twin study participated in an Experience Sampling Method procedure to collect daily life experiences concerning events, event appraisals, and affect. Reward experience was operationalized, as the effect of event appraisal on positive affect (PA). Associations between COMT Val(158)Met genotype and event appraisal on the one hand and PA on the other were examined using multilevel random regression analysis. Ability to experience reward increased with the number of ‘Met’ alleles of the subject, and this differential effect of genotype was greater for events that were experienced as more pleasant. The effect size of genotypic moderation was quite large: subjects with the Val/Val genotype generated almost similar amounts of PA from a ‘very pleasant event’ as Met/Met subjects did from a ‘bit pleasant event’. Genetic variation with functional impact on cortical dopamine tone has a strong influence on reward experience in the flow of daily life. Genetic moderation of ecological measures of reward experience is hypothesized to be of major relevance to the development of various behavioral disorders, including depression and addiction.
Wichers M, Schrijvers D, Geschwind N, Jacobs N, Myin-Germeys I, Thiery E, Derom C, Sabbe B, Peeters F, Delespaul P, van Os J. (Oct 2008). Mechanisms of gene-environment interactions in depression: evidence that genes potentiate multiple sources of adversity. Psychol Med. [Epub ahead of print]
BACKGROUND: Previous work suggests that daily life stress-sensitivity may be an intermediary phenotype associated with both genetic risk for depression and developmental stress exposures. In the current analysis we hypothesized that genetic risk for depression and three environmental exposures over the course of development [prenatal stress, childhood adversity and adult negative life events (NLEs)] combine synergistically to produce the phenotype of stress-sensitivity.MethodTwin pairs (n=279) participated in a momentary assessment study using the Experience Sampling Method (ESM), collecting appraisals of stress and negative affect (NA) in the flow of daily life. Prospective data on birthweight and gestational age, questionnaire data on childhood adversity and recent NLEs, and interview data on depression were used in the analyses. Daily life stress-sensitivity was modelled as the effect of ESM daily life stress appraisals on ESM NA. RESULTS: All three developmental stress exposures were moderated by genetic vulnerability, modelled as dizygotic (DZ) or monozygotic (MZ) co-twin depression status, in their effect on daily life stress-sensitivity. Effects were much stronger in participants with MZ co-twin depression and a little stronger in participants with DZ co-twin depression status, compared to those without co-twin depression. NLE main effects and NLE genetic moderation were reducible to birthweight and childhood adversity. CONCLUSIONS: The findings are consistent with the hypothesis that adult daily life stress-sensitivity is the result of sensitization processes initiated by developmental stress exposures. Genes associated with depression may act by accelerating the process of stress-induced sensitization.
Wright, Kim A.; Lam, Dominic; Brown, Richard G. (Nov 2008). Dysregulation of the behavioral activation system in remitted bipolar I disorder. Journal of Abnormal Psychology, Vol 117(4), pp. 838-848.
The current study tests a prediction of the behavioral activation system (BAS) dysregulation theory of bipolar disorder, namely that following high levels of reward or frustration, individuals with bipolar disorder will take longer than will healthy controls to recover to baseline levels of BAS activity. Eighty individuals (40 with bipolar I disorder, currently euthymic; 40 with no history of affective disorder) completed a daily diary over a 28 day period. No differences were found between the 2 groups in terms of the relation among levels of reward or frustration experienced, magnitude of initial response, or time taken to recover. However, examination of the relation between number of previous episodes and time to recover revealed that history of mania was associated with prolonged activation following reward, whereas history of both mania and depression were associated with prolonged recovery following frustration. The findings do not support an association between lifetime diagnosis of bipolar disorder and slow recovery of BAS activity. Nevertheless, they offer tentative support for an association between number of previous episodes and slow recovery of BAS activity.
Yogarajah M, Powell HW, Smith S, Heaney D, Duncan JS Duncan, Sisodiya S. (Oct 2008). Long-term Monitoring in Refractory Epilepsy: The Gowers Unit Experience. J Neurol Neurosurg Psychiatry. [Epub ahead of print]
INTRODUCTION: Guidelines from NICE and the International League Against Epilepsy recommend long-term EEG monitoring (LTM) in patients in whom seizure or syndrome type is unclear, and in patients in whom it is proving difficult to differentiate between epilepsy and non-epileptic attack disorder (NEAD). The purpose of this study was to evaluate this recommended use of LTM in the setting of an epilepsy tertiary referral unit. METHODS: We reviewed the case notes of all admissions to the Sir William Gowers Unit at the National Society for Epilepsy in the years 2004 and 2005. We recorded the type, duration and result of all LTM performed both prior to and during the admission. Pre- and post-admission diagnoses were compared, and patients were divided according to whether LTM had resulted in a change in diagnosis, refinement in diagnosis or no change in diagnosis. The distinction between change and a refinement in the diagnosis was made on the basis of whether or not this alteration resulted in a change of management. RESULTS: A total of 612 patients were admitted during 2004 and 2005, 230 of whom were referred for diagnostic clarification. Of these, LTM was primarily responsible for a change in diagnosis in 133 (58%), and a refinement of diagnosis in 29 (13%). In 65 (29%) patients the diagnosis remained the same after LTM. In those patients in whom there was a change in diagnosis the most common change was in distinguishing epilepsy from NEAD in 73 (55%) and in distinguishing between focal and generalised epilepsy in 47 (35%). LTM was particularly helpful in differentiating frontal lobe seizures from generalized seizures and non-epileptic attacks. In-patient ambulatory EEG proved as effective as video telemetry (VT) in helping to distinguish between NEAD, focal and generalised epilepsy. DISCUSSION: Our study revealed that LTM led to an alteration in the diagnosis of 71% of patients referred to a tertiary centre for diagnostic clarification of possible epilepsy. Although LTM is relatively expensive, time consuming and of limited availability, this needs to be balanced against the considerable financial and social cost of misdiagnosed and uncontrolled seizures. Our service evaluation supports the use of performing LTM (either video or ambulatory) in a specialist setting in patients who present diagnostic difficulty.
Zheng K, Padman R, Johnson MP, Diamond HS. (Dec 2008). An Interface-Driven Analysis of User Interactions with an Electronic Health Records System. J Am Med Inform Assoc. [Epub ahead of print]
OBJECTIVE To study user interactions with an electronic health records (EHR) system by uncovering hidden navigational patterns in the EHR usage data automatically recorded as clinicians navigated through the system’s software user interface (UI) to perform different clinical tasks. DESIGN A homegrown EHR was adapted to allow real-time capture of comprehensive UI interaction events. These events, constituting time-stamped event sequences, were used to replay how the EHR was used in actual patient care settings. The study site is an ambulatory primary care clinic at an urban teaching hospital. Internal Medicine residents were the primary EHR users. METHODS We apply sequential pattern analysis (SPA) and a first-order Markov chain model to uncover recurring UI navigational patterns. RESULTS Out of 17 main EHR features provided in the system, SPA identified 3 bundled features: “Assessment & Plan” and “Diagnosis”, “Order” and “Medication”, and “Order” and “Laboratory Test”. Clinicians often accessed these paired features in a bundle together in a continuous sequence. The Markov chain analysis revealed a global navigational pathway, suggesting an overall sequential order of EHR feature accesses. “History of Present Illness” followed by “Social History” and then “Assessment & Plan” was identified as an example of such global navigational pathways commonly traversed by the EHR users. CONCLUSION Users demonstrated consistent UI navigational patterns, some of which were not anticipated by system designers or the clinic management. Awareness of such unanticipated patterns may help identify undesirable user behavior as well as reengineering opportunities for improving the system’s usability.
Zittrain J. (Oct 2008). Ubiquitous human computing. Philos Transact A Math Phys Eng Sci. 366(1881):3813-21.
Ubiquitous computing means network connectivity everywhere, linking devices and systems as small as a drawing pin and as large as a worldwide product distribution chain. What could happen when people are so readily networked? This paper explores issues arising from two possible emerging models of ubiquitous human computing: fungible networked brainpower and collective personal vital sign monitoring.