Linked emergence of racial disparities in mental health and epigenetic biological aging across childhood and adolescence.

Marginalization due to structural racism may confer an increased risk for aging-related diseases - in part - via effects on people's mental health. Here we leverage a prospective birth cohort study to examine whether the emergence of racial disparities in mental health and DNA-methylation measures of biological aging (i.e., DunedinPACE, GrimAge Acceleration, PhenoAge Acceleration) are linked across childhood and adolescence. We further consider to what extent racial disparities are statistically accounted for by perinatal and postnatal factors in preregistered analyses of 4898 participants from the Future of Families & Child Wellbeing Study, of which 2039 had repeated saliva DNA methylation at ages 9 and 15 years. We find that racially marginalized children had higher levels of externalizing and internalizing behaviors and diverging longitudinal internalizing slopes. Black compared to White identifying children, children living in more racially segregated neighborhoods, and racially marginalized children more affected by colorism tended to have higher age-9 levels of biological aging and more biological age acceleration over adolescence. Notably, longitudinal increases in internalizing and externalizing behavior were correlated with increases in biological aging. While racial and ethnic disparities in mental health were largely statistically accounted for by socioeconomic variables, differences in biological aging were often still visible after including potential mediating variables. These findings underscore the urgency for future research to consider biological aging processes from early life and collect more comprehensive measures of structural racism in developmental cohorts. Programs dedicated to advancing racial health equity must address the psychological and physical effects of structural racism on children and adolescents.