Drink more, sleep less: Applying compositional data analysis to investigate day-to-day associations between alcohol use and 24-hour movement behaviors

Background. Alcohol use impacts sleep; however, sleep is also impacted by other 24-hour movement behaviors, including sedentary behavior (SB) and physical activity (PA). This study used compositional data analysis (CoDA) to simultaneously account for SB and PA and investigate within- and between-person associations between sleep and alcohol use behaviors. Methods. Participants were 21-44-year-old overweight/obese adults. Across 21 days, participants wore an activPAL monitor to assess sleep, PA, and SB hours, and completed morning surveys of past day alcohol use to assess drinks/day. CoDA identified the daily proportions of time spent in sleep, PA, and SB. Multilevel models investigated within- and between-person associations between sleep, demographic factors, and alcohol use. Differences in sleep, SB, and PA across drinking versus non-drinking days were investigated with individual MANOVAs for each participant. Results. Participants (N=91, Mage=30.7{+/-}6.5, 57% female, 75% White) reported drinking on 23% (n=437) of days, consumed 1 drink/day, and averaged 8.5{+/-}2.3 sleep hours, 7.4{+/-}2.8 SB hours, and 8.0{+/-}2.7 PA hours per day. Multilevel models indicated that participants slept 16.6 fewer minutes on drinking days (p=.046) each additional drink corresponded with 4.4 fewer minutes of sleep (p=.04). There was large between-person variability in time use allocations across drinking versus non-drinking days. For many the change was non-significant; however, three participants spent significantly less time sleeping on drinking days (1.16-4.74 fewer hours of sleep) and one participant spent significantly (2.62) more hours sleeping on drinking versus non-drinking days. Conclusions. Drinking days and greater alcohol consumption were associated with fewer minutes of sleep within-people; however, shifts towards PA and SB were inconsistent. Investigating contextual factors, such as the physical/social context of alcohol use, the time-of-day drinking occurs, the type of alcohol consumed, or the type of PA a person engages in could provide deeper insight into the conditions under which alcohol use detrimentally impacts sleep.