Increase in the Number and Duration of Sleep Episodes During Class After Reopening of Schools Following Closure due to COVID-19

Sleep is important for the well-being of school-aged children. Almost all schools in Hyogo prefecture in Japan were closed from April 7 to May 31, 2020, owing to the coronavirus disease 2019 pandemic. The pandemic restrictions resulted in the disruption of the sleep routines of children. The number of children who experienced sleepiness in class after school closure increased. The number of children who visited our hospital 1 year before and after the closure was 208 (11.73 ± 3.24 years of age) and 155 (11.45 ± 3.30 years), respectively. The number of chief complaints of sleep-related symptoms at the first visits showed no significant difference between the two time periods. The percentage of patients who slept during class increased (but not significantly) after the school closure. However, the mean number and duration of sleep episodes during class significantly increased from 0.31 ± 0.76 to 1.04 ± 1.14 episodes/day and from 15.8 ± 38.6 to 45.7 ± 46.9 min/day (each P < 0.001) before and after school closure, respectively. The total number of patients in our hospital with the primary central disorders of hypersomnolence, i.e., narcolepsy, idiopathic hypersomnia, and Kleine–Levin syndrome, and the number of patients with insufficient sleep syndrome after the school closure significantly increased compared with those before closure (P = 0.034 and 0.048, respectively). School closure was associated with an increased incidence of sleeping during class; therefore, maintaining a stable daily routine for children with sleep disorders could have an alleviating effect.