Epigenetic age acceleration and psychosocial stressors in early childhood.

The impact of psychosocial stress on mental and physical health is well-documented. Adverse experiences that occur early in life are particularly impactful on later life health. Epigenetic modifications, such as DNA methylation, have been proposed as a possible mechanism to mediate the impact of childhood events on adult health outcomes. The development of epigenetic clocks to estimate epigenetic age has revealed many examples of epigenetic age acceleration (and deceleration) in association with exposure to psychosocial stressors. Furthermore, altered epigenetic aging has been associated with downstream health outcomes. Here studies are discussed that have reported associations of epigenetic aging with early-life exposure to psychosocial stressors, such as childhood abuse and neglect, and with later-life health outcomes, including increased mortality, morbidity, and disease risk. Protective factors that may mitigate the effect of psychosocial stress on epigenetic aging, and possibly enable reversal of epigenetic aging, are also discussed.