The role of stress proliferation in linking childhood stressors to accelerated biological aging

Adverse childhood experiences (ACEs) are linked to negative health outcomes, but research has not examined the extent to which stress proliferation—the tendency of initial stressors to beget subsequent stressors—explains their association with accelerated biological aging. Using data from 2201 adults in the Person-to-Person Health Interview Study (mean age = 50, SD = 18.6; 61% female; 85% White) and second- and third-generation epigenetic clocks (AgeAccelGrim2 and DunedinPACE), we test whether adult stressors mediate the relationship between ACEs and biological aging, distinguishing between stressful life events and chronic financial strain as pathways. Results show that greater exposure to ACEs is associated with accelerated biological aging both directly and indirectly. Causal mediation analyses indicate that chronic financial strain accounts for 50% of the ACEs–AgeAccelGrim2 association and 47% of the ACEs–DunedinPACE association, while discrete events account for 42% of the ACEs–AgeAccelGrim2 association (the pathway through discrete events is not significant for DunedinPACE). Findings suggest that stressors in adulthood, including financial strain as well as acute stressful experiences like getting divorce or being fired, may be an important pathway through which early adversity contributes to physiological aging.