Relationships between sleep duration and adolescent depression: a conceptual replication

Objective: Given the growing concern about research reproducibility, we conceptually replicated a previous analysis of the relationships between adolescent sleep and mental well-being using a new dataset. Methods: We conceptually reproduced an earlier analysis (Sleep Health, June 2017) using baseline data from the START Study. START is a longitudinal research study designed to evaluate a natural experiment in delaying high school start times, examining the impact of sleep duration on weight change in adolescents. In both START and the previous study, school day bedtime, wake-up time, and answers to a 6-item depression subscale were self-reported using a survey administered during the school day. Logistic regression models were used to compute the association and 95% confidence intervals between the sleep variables (sleep duration, wake-up time, and bedtime) and a range of outcomes. Results: In both analyses, greater sleep duration was associated with lower odds (P <.0001) of all 6 indicators of depressive mood. Five of the 6 sleep duration point estimates from the START Study and 4 of the 6 wake-up time point estimates fell within the 95% confidence intervals from the previous analysis. However, the associations between wake-up time and outcomes differed between the 2 studies' analyses. Conclusion: Our findings add strength to the evidence supporting an association between short sleep duration and depression. This issue deserves attention from school districts given the current epidemic of short sleep duration among youth and the potential impact school scheduling can have on teen sleep.