Association of social jetlag and eating patterns with sleep quality and daytime sleepiness in Japanese high school students

Summary A high prevalence of excessive daytime sleepiness and poor sleep quality has been reported in adolescents, but the effects of social jetlag on sleep quality and daytime sleepiness are unclear. Therefore, we assessed the association of sleep and eating patterns with daytime sleepiness and sleep quality among a total of 756 Japanese high school students. Participants completed the Pittsburgh Sleep Quality Index to evaluate sleep quality, the Pediatric Daytime Sleepiness Scale to evaluate daytime sleepiness, and an 8‐day sleep diary. Data on average sleep duration, social jetlag, midsleep on free days sleep corrected, and the differences in the first and last meal timing between school days and non‐school days were obtained from participants' sleep diaries. The results reveal that social jetlag is associated with differences in the first meal timing between school days and non‐school days, and that social jetlag of more than 2 hr is associated with extremely poor sleep quality and excessive daytime sleepiness in Japanese high school students. Our findings suggest that reducing social jetlag to within a 2‐hr window is important to prevent poor sleep quality and excessive daytime sleepiness for this population.