Adverse Childhood Experiences Associated with Epigenetic Age and Depressive Symptoms in Older Adults

Adverse childhood experiences (ACEs) increase risk for depression in adolescents and older adults and have been linked to accelerated biological aging. We hypothesized that accelerated epigenetic aging may partially explain the link between ACEs and depression. This study examines second-generation epigenetic clocks (viz., GrimAge, PhenoAge, and DunedinPoAm38) as mediators of the link between ACEs and depressive symptoms in older adulthood. We utilize structural equation modeling to assess mediation in the Innovative Subsample of the Venous Blood Study from the Health and Retirement Study (N = 2672). Results indicate that experiencing more than 1 ACE is significantly associated with greater GrimAge and DunedinPoAm38, with limited evidence of increasing aging with increasing ACEs. GrimAge and DunedinPoAm38 were also significantly associated with more depressive symptoms. These associations were partially reduced by lifestyle factors. GrimAge explained between 9 and 13% of the association between ACEs and adult depressive symptoms, and DunedinPoAm38 explained between 2 and 7% of the association between ACEs and adult depressive symptoms. Findings indicate that accelerated aging, as measured by GrimAge and DunedinPoAm38, is strongly associated with ACEs in older Americans, that these clocks are highly associated with depressive symptoms in older Americans, and that these clocks mediate a proportion of the association between ACEs and adult depressive symptoms. Epigenetic clocks may represent a physiological mechanism underlying the link between early life adversity and adult depression. Lifestyle factors are a potential area for intervention.