0169 Variability in Sleep and Eating are Associated with Subclinical Atherosclerosis in Early Adulthood

Abstract

Abstract Introduction Experimental studies show that sleeping and eating at times that do not align with one’s endogenous biological timing (‘circadian misalignment’) promotes a physiological environment that favors cardiovascular disease (CVD) development. Day-to-day variability in sleep and eating are considered common causes of circadian misalignment in the general population. While emerging evidence suggests that variability in sleep and eating behaviors predicts overt CVD in middle-aged and older adults, the extent to which these behaviors relate to biomarkers of CVD development in subclinical stages has not been fully elucidated. Methods Adults without chronic health conditions or sleep disorders completed 14 days of concurrent sleep and dietary assessments via continuous wrist actigraphy and time-stamped photo-assisted diet records, respectively. Variability in sleep duration, sleep midpoint, eating onset/offset (clock time of first and last caloric consumption, respectively), and caloric midpoint (clock time at which 50% of total daily calories are consumed) were quantified for each variable, operationalized as the standard deviation (SD) across the monitoring period. Multivariable regression models determined the cross-sectional association between metrics of sleep and eating variability with carotid intima-media thickness (CIMT), an established biomarker of subclinical atherosclerosis, measured at end-diastole via B-mode ultrasonography. Models adjusted for age, sex, resting systolic blood pressure, sleep duration, and total daily caloric intake. Results Participants (N=61) were 29.1±7.1 years, 66% female, with a blood pressure of 113±9/70±7 mmHg. Variability in sleep midpoint (p=0.19), eating onset (p=0.19), and eating offset (p=0.40) were not associated with CIMT. Alternatively, each 60-minute increase in sleep duration SD was associated with a 0.05±0.02 mm greater CIMT (p=0.005), while each 60-minute increase in caloric midpoint SD was associated with a 0.04±0.01 mm greater CIMT (p=0.009). Sleep duration SD (p=0.02) and caloric midpoint SD (p=0.04) remained associated with CIMT in an exploratory adjusted model that included both variables. Conclusion Metrics of sleep and eating variability are associated with subclinical atherosclerosis in free-living adults. These data support a growing body of literature indicating that encouraging regularity in nightly sleep duration and the timing of daily caloric consumption may represent behavioral strategies to mitigate risk for overt CVD. Support (if any) American Heart Association (#831488); University of Delaware Research Fund-SI Award