Childhood adversity and adolescent epigenetic age acceleration: the role of adolescent sleep health.

Study Objectives: We investigated how a dimension of early life adversity (ELA), capturing threat in the home, relates to later epigenetic age acceleration in adolescence through sleep (duration, efficiency, and timing) to empirically test theoretical models suggesting the importance of sleep as a key mechanism linking ELA with poor health outcomes and to expand the limited literature on sleep and epigenetic aging among youth. Methods: We utilized data from 861 participants in the Future of Families and Child Wellbeing Study who participated in the actigraphy substudy at age 15. Sleep variables used were average total sleep time (TST), sleep efficiency (SE), and sleep onset timing. Home threat was determined at ages 3, 5, and 9 from parent reports on the Child Conflict Tactics Scale, and epigenetic aging was measured through DNA methylation analyses of saliva samples collected at age 15. Results: Higher levels of childhood home threat exposure were associated with less adolescent TST, lower SE, and later sleep onset timing. Adolescent SE and timing were associated with a faster pace of aging and epigenetic age acceleration. SE and timing mediated the link between childhood home threat exposure and adolescent epigenetic aging. Conclusions: Epigenetic embedding of childhood threat exposure in the home may occur through adversity-related sleep disturbances in adolescence. Findings warrant greater attention to pediatric sleep health in theoretical models of biological embedding of adversity and point to sleep health improvement as a potential way to prevent adversity-related epigenetic age acceleration.