COVID-19 instructional approaches (in-person, online, hybrid), school start times, and sleep in over 5,000 U.S. adolescents.

STUDY OBJECTIVES: To examine associations among instructional approaches, school start times, and sleep during the COVID-19 pandemic in a large, nationwide sample of U.S. adolescents. METHODS: Cross-sectional, anonymous self-report survey study of a community-dwelling sample of adolescents (grades 6-12), recruited through social media outlets in October/November 2020. Participants reported on instructional approach (in-person, online/synchronous, online/asynchronous) for each weekday (past week), school start times (in-person or online/synchronous days), and bedtimes (BT) and wake times (WT) for each identified school type and weekends/no school days. Sleep opportunity was calculated as BT-to-WT interval. Night-to-night sleep variability was calculated with mean square successive differences. RESULTS: Respondents included 5,245 racially and geographically diverse students (~50% female). BT and WT were earliest for in-person instruction; followed by online/synchronous days. Sleep opportunity was longer on individual nights students did not have scheduled instruction (>1.5 h longer for online/asynchronous than in-person). More students obtained sufficient sleep with later school start times. However, even with the same start times, more students with online/synchronous instruction obtained sufficient sleep than in-person instruction. Significantly greater night-to-night variability in sleep-wake patterns was observed for students with in-person hybrid schedules versus students with online/synchronous + asynchronous schedules. CONCLUSIONS: These findings provide important insights regarding the association between instructional approach and school start times on the timing, amount, and variability of sleep in U.S. adolescents. Given the public health consequences of short and variable sleep in adolescents, results may be useful for education and health policy decision-making for post-pandemic secondary schools.

Sleep of preschoolers during the coronavirus disease 2019 (COVID-19) outbreak.

Coronavirus disease 2019 (COVID-19) has resulted in a significantly large number of psychological consequences, including sleep health. The present study evaluated sleep patterns, sleep disturbances, and associated factors in Chinese preschoolers confined at home during the COVID-19 outbreak. Caregivers of 1619 preschoolers (aged 4-6 years) recruited from 11 preschools in Zunyi, Guizhou province completed the Children's Sleep Habit Questionnaire (CSHQ) between 17th and 19th February 2020. Data were compared to a sociodemographically similar sample of preschoolers (included in the 11 preschools) in 2018. Compared to the 2018 sample, the confined preschoolers demonstrated changes in sleep patterns characterized by later bedtimes and wake times, longer nocturnal and shorter nap sleep durations, comparable 24-hr sleep duration, and fewer caregiver-reported sleep disturbances. Moreover, behavioural practices (sleeping arrangement, reduced electronic device use, regular diet) and parenting practices (harmonious family atmosphere and increased parent-child communication) were associated with less sleep disturbances in the confined sample. The present study provides the first description of the impact of prolonged home confinement during the COVID-19 outbreak on sleep patterns and sleep disturbances in preschoolers, as well as highlighting the importance of the link between sleep health and family factors. Given that disrupted and insufficient sleep has been linked to immune system dysfunction, our findings also have potential implications for resilience to infection in young children during the COVID-19 pandemic. Future studies should further explore deficient sleep as a risk factor for coronavirus infection.