Search

Sleep disturbances, chronotype and social jetlag (SJL) have been associated with increased risks for major chronic diseases that take decades to develop, such as obesity, metabolic syndrome and cardiovascular disease. Potential relationships between poor sleep, chronotype and SJL as they relate to metabolic risk factors for chronic disease have not been extensively investigated. This prospective study examined chronotype, SJL and poor sleep in relation to both obesity and elevated blood pressure among healthy young adults. SJL and objective sleep measures (total sleep time, sleep onset latency, wake after sleep onset and sleep efficiency) were derived from personal rest/activity monitoring (armband actigraphy) among 390 healthy adults 21-35 years old. Participants wore the device for 6-10 days at 6-month intervals over a 2-year period (n = 1431 repeated observations). Chronotypes were categorized into morning, intermediate and evening groups using repeated measures latent class analysis. Means of SJL and sleep measures among latent chronotype groups were compared using partial F-tests in generalized linear mixed models. Generalized linear mixed models also were used to generate odds ratios (ORs) with 95% confidence intervals (CIs) examining the relationship between repeated measures of chronotype, SJL, sleep and concurrent anthropometric outcome measures (body mass index, percentage of body fat, waist-to-hip ratio, waist-to-height ratio), systolic blood pressure and diastolic blood pressure. Sleep latency ≥12 min was associated with increased odds of a high waist-to-height ratio (OR = 1.37; CI: 1.03-1.84). Neither chronotype nor SJL was independently associated with anthropometric outcomes or with blood pressure. Relationships between poor sleep and anthropometric outcomes or blood pressure varied by chronotype. Morning types with total sleep time <6 h, sleep efficiency <85% or wake after sleep onset ≥60 min were more likely to have an increased percentage of body fat, waist-to-hip ratio and waist-to-height ratio relative to those with an intermediate chronotype. Similarly, sleep latency ≥12 min was associated with increased odds of elevated systolic blood pressure (OR = 1.90; CI: 1.15-3.16, pinteraction = 0.02) among morning versus intermediate chronotypes. No relationships between poor sleep and obesity or elevated blood pressure were observed among evening chronotypes. The results from this study among healthy young adults suggest that poor sleep among morning types may be more strongly associated with obesity and elevated blood pressure relative to those with an intermediate (neutral) chronotype. Sleep-related metabolic alterations among different chronotypes warrant further investigation. [ABSTRACT FROM AUTHOR]

Sleep disruption has been associated with increased risks for several major chronic diseases that develop over decades. Differences in sleep/wake timing between work and free days can result in the development of social jetlag (SJL), a chronic misalignment between a person's preferred sleep/wake schedule and sleep/wake timing imposed by his/her work schedule. Only a few studies have examined the persistence of SJL or sleep disruption over time. This prospective investigation examined SJL and sleep characteristics over a 2-year period to evaluate whether SJL or poor sleep were chronic conditions during the study period. SJL and sleep measures (total sleep time [TST], sleep onset latency [SOL], wake after sleep onset [WASO]), and sleep efficiency [SE]), were derived from armband monitoring among 390 healthy men and women 21-35 years old. Participants wore the armband for periods of 4-10 days at 6-month intervals during the follow-up period (N = 1431 repeated observations). The consistency of SJL or sleep disruption over time was analyzed using generalized linear mixed models (GLMMs) for repeated measures. Repeated measures latent class analysis (RMLCA) was then used to identify subgroups among the study participants with different sleep trajectories over time. Individuals in each latent group were compared using GLMMs to identify personal characteristics that differed among the latent groups. Minor changes in mean SJL, chronotype, or TST were observed over time, whereas no statistically significant changes in SOL, WASO, or SE were observed during the study period. The RMLCA identified two groups of SJL that remained consistent throughout the study (low SJL, mean ± SE: 0.4 ± 0.04 h, 42% of the study population; and high SJL, 1.4 ± 0.03 h, 58%). Those in the SJL group with higher values tended to be employed and have an evening chronotype. Similarly, two distinct subgroups were observed for SOL, WASO, and SE; one group with a pattern suggesting disrupted sleep over time, and another with a consistently normal sleep pattern. Analyses of TST identified three latent groups with relatively short (5.6 ± 1.0 h, 21%), intermediate (6.5 ± 1.0 h, 44%), and long (7.3 ± 1.0 h, 36%) sleep durations, all with temporally stable, linear trajectories. The results from this study suggest that sleep disturbances among young adults can persist over a 2 year period. Latent groups with poor sleep tended to be male, African American, lower income, and have an evening chronotype relative to those with more normal sleep characteristics. Characterizing the persistence of sleep disruption over time and its contributing factors could be important for understanding the role of poor sleep as a chronic disease risk factor. [ABSTRACT FROM AUTHOR]

Energy flux, the rate of energy conversion from absorption to expenditure or storage, is a critical component of understanding weight management. Individuals who maintain body weight over time have common characteristics including a relatively high level of physical activity and minimal changes in body composition, muscle mass and metabolic rate. A higher state of energy flux resulting from high energy expenditure may provide for a greater ‘sensitivity’ between energy intake and expenditure. This sensitivity stabilizes body weight by enhancing reciprocal compensation among these components with changes in eating or activity. The energy balance framework suggests that a higher level of energy expenditure requires higher energy intake to maintain body mass. Maintaining energy balance at a higher caloric intake and expenditure should be a more successful long-term strategy for weight maintenance than reduced consumption or extreme caloric restriction at a low level of energy expenditure (a low energy flux) and improve intervention effectiveness for sustainable methods for body weight stability. [ABSTRACT FROM PUBLISHER]

Recent data show that people living with HIV/AIDS (PLWHA) are at a greater risk of cardiovascular disease (CVD), which could possibly be explained by an increased prevalence of metabolic syndrome (MetSyn) due to the known toxicities associated with antiretroviral therapy (ART). The purpose of this study is to examine the relationships between physical activity (PA) and components of MetSyn in a sample of PLWHA taking ART. A total of 31 males and 32 females living with HIV and currently taking ART were enrolled in a home-based PA intervention aimed to reduce risk factors for CVD. Clinical assessments included measures of resting blood pressure (BP), waist circumference, height, weight, PA levels via accelerometer, and a fasted blood draw. Components of MetSyn were divided into three clusters (1 = 0–1; 2 = 2; 3 = 3 or more). A one-way analysis of variance was used to determine differences between clusters. Multiple linear regressions were used to identify significant associations between moderate intensity PA (MPA) and sedentary time among components of MetSyn. MPA was significantly lower across MetSyn clusters (p< 0.001), whereas sedentary time was significantly higher (p= 0.01). A multiple linear regression showed MPA to be a significant predictor of waist circumference after controlling for age, race, gender, and sedentary time. Routine PA can be beneficial in helping PLWHA reduce waist circumference ultimately leading to metabolic improvements. This in turn would help PLWHA self-manage known components of MetSyn, thus reducing their risk of CVD and mortality. [ABSTRACT FROM AUTHOR]

The overarching goals of the evaluation are to assess the use of community-based interventions as an alternative to residential commitments for delinquent youth, and determine why some youth escalate from community-sanctions to residential placement. Using logistic regression and propensity score matching techniques, the study examined pathways through the continuum of care, and the relative effectiveness of probation and residential dispositions. All youth disposed to either juvenile probation (n = 2,823) or residential facilities (n = 269) in Connecticut between July 1, 2005 and June 30, 2007 were included in the study. The results demonstrate that delaying delinquency and increasing family protective factors help prevent youth escalation through the system. Further, an assessment of comparable probation and residential placements revealed that probationers had significantly lower recidivism than those placed in commitment programs. These findings suggest that community-based supervision is an effective alternative to more restrictive and costly residential services for some juvenile delinquents; and highlight important considerations for reducing system escalation. [ABSTRACT FROM PUBLISHER]

A growing body of evidence demonstrates a significant relationship between spirituality and health. HIV-infected individuals often find new meaning and purpose for their lives while establishing new connections and strengthening old ones. This descriptive, correlational study examined the relationships among spiritual well-being, sleep quality, and health status in 107 HIV-infected men and women. Spiritual well-being was found to be a significant factor related to both sleep quality and mental and physical health status. Every study participant reported sleep disturbance. The findings suggest that spiritual well-being and sleep quality need to be assessed so appropriate interventions can be implemented to improve health outcomes in this population. [ABSTRACT FROM AUTHOR]