Associations of weekday-to-weekend sleep differences with academic performance and health-related outcomes in school-age children and youths.

Weekday-to-weekend sleep discrepancy is a common phenomenon in school-age children and youths. However, the effects of weekday-to-weekend sleep differences remain unclear. A systematic review that included 72 observational studies was conducted to examine the association of weekday-to-weekend differences in bedtime, rise time, mid-point of sleep and sleep duration with academic performance and health-related outcomes in children and youths. Weekday-to-weekend difference in sleep timing (e.g., bedtime) was associated with poorer academic performance and depressive symptoms in in youths, particularly secondary school students, and a higher risk of substance use as well as overweight/obesity in the overall samples. In addition, weekday-to-weekend difference in sleep duration showed a modest association with poorer academic performance and depressive symptoms in the overall samples, as well as a higher risk of overweight/obesity, particularly in Asian children and youths. Albeit limited evidence, greater sleep differences were related to an increased risk of behavioral problems and suicidality. Findings on the associations between weekday-to-weekend sleep differences and specific cognitive abilities, anxiety, and cardiometabolic risks were limited and inconclusive. Longitudinal and experimental studies utilizing objective sleep measures are recommended to further examine the impacts of weekday-to-weekend sleep differences on mental and physical health, and to gain more insight into the mechanisms underlying their associations.