The relationship between sleep and physical activity: the moderating role of daily alcohol consumption.

STUDY OBJECTIVES: Studies have demonstrated a daily, bidirectional relationship between sleep and physical activity. However, little is known about how other health behaviors, such as alcohol consumption affect this relationship. This study examined how daily and average alcohol consumption affects the relationships between sleep and physical activity. METHODS: Participants included 70 men and women, ages 18-50 with sleep duration >6.5 hours. Participants wore an actigraph, physical activity monitor and recorded number of alcoholic drinks by daily food logs for 7 days. Results were analyzed using multi-level models to evaluate the 7-day average (i.e. between-person effects) and daily effects (i.e. within-person effects) simultaneously. RESULTS: Those with more average (7 day) minutes of vigorous physical activity had less wake after sleep onset (WASO). Furthermore, a higher number of alcoholic drinks was associated with longer sleep duration and higher WASO over 7 days. Days with a higher number of alcoholic drinks were associated with higher WASO and sleep fragmentation that night. Alcohol intake moderated the average (7 days) and daily relationships between sleep and physical activity such that high average (7 days) WASO was associated with shorter average total physical activity duration, but only for those with higher alcohol intake. In addition, longer physical activity duration during the day was associated with lower sleep fragmentation that night, but only for those with lower alcohol intake. CONCLUSIONS: These data demonstrate that in a naturalistic setting, alcohol intake negatively impacts sleep and diminishes the benefits of physical activity on sleep.

Association of depressive symptoms, trait anxiety, and perceived stress with subclinical atherosclerosis: results from the Chicago Healthy Aging Study (CHAS).

OBJECTIVE: Examine the association between multiple psychological factors (depressive symptoms, trait anxiety, perceived stress) and subclinical atherosclerosis in older age. METHOD: This cross-sectional study included 1101 adults ages 65-84 from the Chicago Healthy Aging Study (CHAS - 2007-2010). Previously validated self-report instruments were used to assess psychological factors. Non-invasive methods were used to assess subclinical atherosclerosis in two regions of the body, i.e., ankle-brachial blood pressure index (ABI) and coronary artery calcification (CAC). Multivariate logistic regression was used to examine the association between each psychological measure and subclinical atherosclerosis, after the adjustment for socio-demographic factors, sleep quality, young adulthood/early middle age and late-life CVD risk status, and psychological ill-being as appropriate. RESULTS: The burden of major cardiovascular disease risk factors did not significantly differ across tertiles of psychological factors. In multivariate adjusted models, trait anxiety was associated with calcification: those in the second tertile were significantly more likely to have CAC >0 compared to those in the lowest anxiety tertile [OR=1.68; 95% CI=1.09-2.58], but no significant difference was observed for Tertile III of trait anxiety [OR=1.31; 95% CI=0.75-2.27]. No association was seen between psychological measures and ABI. CONCLUSION: Of several psychological factors, only trait anxiety was significantly associated with CAC.

Phase-shifting response to light in older adults.

Age-related changes in circadian rhythms may contribute to the sleep disruption observed in older adults. A reduction in responsiveness to photic stimuli in the circadian timing system has been hypothesized as a possible reason for the advanced circadian phase in older adults. This project compared phase-shifting responses to 2 h of broad-spectrum white light at moderate and high intensities in younger and older adults. Subjects included 29 healthy young (25.1 ± 4.1 years; male to female ratio: 8: 21) and 16 healthy older (66.5 ± 6.0 years; male to female ratio: 5: 11) subjects, who participated in two 4-night and 3-day laboratory stays, separated by at least 3 weeks. Subjects were randomly assigned to one of three different time-points, 8 h before (-8), 3 h before (-3) or 3 h after (+3) the core body temperature minimum (CBTmin) measured on the baseline night. For each condition, subjects were exposed in a randomized order to 2 h light pulses of two intensities (2000 lux and 8000 lux) during the two different laboratory stays. Phase shifts were analysed according to the time of melatonin midpoint on the nights before and after light exposure. Older subjects in this study showed an earlier baseline phase and lower amplitude of melatonin rhythm compared to younger subjects, but there was no evidence of age-related changes in the magnitude or direction of phase shifts of melatonin midpoint in response to 2 h of light at either 2000 lux or 8000 lux. These results indicate that the acute phase-shifting response to moderate- or high-intensity broad spectrum light is not significantly affected by age.