The following is a summary of “Stressful life events and accelerated biological aging over time in youths,” published in the May 2023 issue of Psychoneuroendocrinology by Sumner et al.
Experiencing adversity in childhood and adolescence, including stressful life events (SLEs), may hasten development, resulting in poor mental and physical health. However, most research on adverse early experiences and biological aging (BA) in adolescents is cross-sectional. Researchers examined whether SLEs predicted the rate of change in two BA metrics: epigenetic age and Tanner stage, in 171 adolescents followed for approximately two years. In addition, they examined whether the rate of change in BA was related to variations in depressive symptoms over time. Youths aged 8–16 years at baseline self-reported Tanner stage and depressive symptoms at baseline and follow-up assessments and provided saliva samples for DNA analysis at both reviews.
Horvath epigenetic age estimations were derived from Illumina EPIC array-measured DNA methylation data. At follow-up, adolescents and caregivers were administered contextual threat interviews to assess youths’ experiences with SLEs over the past year. An independent rating team objectively classified interviews to generate an SLE impact score that reflects the severity of all SLEs that occurred during the previous year. The rate of change in BA metrics was operationalized as a function of the shift in epigenetic age or Tanner stage between assessments. A greater rate of change in epigenetic age was associated with higher objective SLE impact scores over time (β = 0.21, P =.043). In addition, among adolescents whose Tanner stage at baseline was lower but not higher, there was a positive relationship between SLE impact scores and rate of change in the Tanner stage (Baseline Tanner Stage × SLE Impact Score interaction: β = -0.21, P=.001).
Adjusting for baseline symptoms, a greater rate of change in epigenetic age was also associated with higher levels of depressive symptoms at follow-up (β = 0.15, P =.043). When epithelial (buccal) cell proportions were accounted for, the associations with epigenetic age remained similar, albeit attenuated slightly. They demonstrate that more commonly experienced SLEs during adolescence may also contribute to accelerated BA, whereas most research on adolescents has focused on severe early adversity experiences. More research is required to comprehend the long-term health effects of changes in BA metrics.