Associations between objective sleep duration, sleep duration variability, and sleep onset with emotion regulation and internalizing symptoms in adolescents: findings from the ABCD® study

Poor sleep and mental health are closely linked in adolescents, but most studies have relied on self-reported sleep measures. We investigated cross-sectional associations between objective sleep features (sleep duration, variability, and onset time) and mental health outcomes (internalizing symptoms and emotion regulation) in 1,371 U.S. adolescents from the Adolescent Brain Cognitive Development℠ Study (ABCD®) [year 4 follow-up; mean age 14.09±0.69, 51.84% female] controlling for age, sex, race/ethnicity, and parental education.Sleeping ≤7.05 hours (β=0.06 [95% CI: 0.00–0.11], p=0.036), greater sleep duration variability (β=0.09 [0.03–0.14], p=0.001), with stronger effects in females (interaction: β=-0.12 [-0.22–-0.02], p=0.020), and later sleep onset times (β=0.06 [0.01–0.11], p=0.030) were all associated with greater internalizing symptoms. Sleep was not linked to reappraisal (all p>0.05). Higher variability was associated with greater suppression (β=0.09 [0.03–0.14], p=0.001).Objective sleep features were differentially associated with mental health outcomes, highlighting that thoughtful sleep interventions can support adolescent well-being.