220 Sleep schedule changes during the COVID-19 pandemic: Relations to circadian preferences

Ruder, Michael; Gahan, Luke; O’Mullane, Brian; Watson, Nathaniel; Raymann, Roy

INTRODUCTION: The COVID-19 pandemic profoundly altered individual lifestyles, reducing commutes and restricting nocturnal in-person socialization. We examine whether the stay-at-home orders and the attendant increase in sleep scheduling autonomy, impact bedtimes and waketimes and influence circadian preference alignment. METHODS: We compared bedtimes and wake times during the 4 weeks before and after a March 19th, 2020 stay-at-home order announcement. Data from the PSG-validated SleepScore Mobile Application were analyzed. Users answering a circadian preference question (a five-point Likert scale ranging from “definitely a morning person” to “definitely an evening person”) who also recorded 10 or more nights of sleep both before and after the March 19th announcement were included in the analysis. The data set included 69,656 total nights of sleep from 1,487 users: 51.0% female, age range 18 to 91 years (mean = 50.3 +/- 30.3). Differences in average bedtime and wake time before and after March 19th were compared using paired sample t-tests. Associations between circadian preference and changes in bedtime and wake time were examined using Spearman’s correlation coefficient. RESULTS: All five circadian preference groups showed a significant delay in both bedtime and wake time (p < .01) after the March 19th announcement. Greatest delays were observed in those reporting the strongest eveningness preference, with median bedtimes being 17 minutes later and wake times 33 minutes later. Delays were smallest in users with the strongest morningness preference, with bedtimes being 7 minutes later and wake times 12 minutes later. Wake time delay was significantly greater than bedtime delay for evening types (p < 0.001) but not morning types. Eveningness preference was associated with greater bedtime delay (Spearman correlation = 0.098, p <0.001) and wake time delay (Spearman correlation= 0.178, p < 0.000001). CONCLUSION: The stay-at-home order provided many individuals more freedom to choose their sleep schedule. This increased sleep scheduling autonomy was associated with delayed bedtimes and wake times for each circadian preference group, with the evening-types exhibiting the greatest shift towards a later sleep schedule. We conclude that stay-at-home orders allowed evening types to choose sleep schedules more aligned with their natural tendencies. Support (if any):