The Effects of Long-term Social Distancing on Sleep and Mood in Adolescents During the COVID-19 Pandemic

Background: School timings could influence teens' sleeping patterns by interrupting their sleep or the timing of light can shift their biological clock. The COVID-19 pandemic has altered teens’ sleeping schedule making it important to analyze the effects of long-term social distancing on adolescents’ sleep and mood. Objectives: This study analyzes the effects of long-term social distancing, due to the COVID-19 pandemic, on their sleeping patterns and mood. Methods: In this cohort study, data from the 2018 – 2020 Korea Youth Risk Behavior Web-based Survey (KYRBS) were used to compare teens’ sleep patterns in 2020 with those in 2018 – 2019. The primary outcomes of this study were the sleep duration and sleep time of adolescents throughout the week, between 2018 and 2019, and in 2020. The secondary outcomes were the teens’ mood, health perception, and sleep satisfaction, including differences in total sleep time and sleep discrepancies between weekends and weekdays. Results: Around 58 – 63 thousand students were surveyed each year, and the participation rate was 94.9 – 95.6%. After exclusion, 132,839 teens participated in the survey. From 2018–2020, the height and body weight of the participants did not change. After adjusting for participants’ sex and school year, it was found that more teens felt happy, fewer teens experienced sadness and desperation, and fewer teens had suicidal thoughts in 2020, compared with the previous two years. They also slept 10 minutes later (9.743 (95% confidence interval 7.954 - 11.530)), with wake-up times of 3 – 5 minutes later on weekdays (4.684 (3.449 - 5.919)). On weekends during social distancing, they slept 16 minutes later (15.721 (14.077 - 17.366)), with wake-up times of 12 minutes later (12.309 (10.393 - 14.225)). Although they slept five minutes less on weekdays (-5.059 (-6.817 to -3.301)) and three minutes less on weekends (-3.413 (-5.419 to -1.407)), their overall sleep satisfaction increased, and differences in sleep duration between weekdays and weekends decreased in 2020. Conclusions: During social distancing, the mood and sleep efficiency of teens improved. In the future, once the COVID-19 pandemic subsides, online classes can be included in the curriculum of school systems to ensure healthy sleep patterns in teenagers.