Sex Differences in Associations Between Adversity and Biological Ageing

Adverse events across the life course have been linked to older biological ageing profiles. Whether these associations differ between males and females, and whether such differences depend on adversity occurring in childhood, adulthood or both periods, remains unclear. In 153,557 UK Biobank participants aged 40-69 years, we assessed associations of childhood and/or adulthood adversity with metabolomic ageing, frailty, telomere length and grip strength. Sex differences were evaluated using stratified analyses and sex-by-adversity interaction tests. Exposure to adversity in childhood and/or adulthood was reported by 64.6% of males and 69.6% of females. Childhood adversity was associated with multiple ageing markers primarily in females, including a metabolite-predicted age exceeding chronological age, greater frailty, shorter telomeres and weaker grip strength. Adulthood adversity was more strongly associated with certain ageing markers in males, particularly greater frailty and weaker grip strength. This divergence in sex-specific associations between childhood and adulthood exposure was consistent across several markers, with statistically significant sex-by-adversity interactions for frailty and grip strength. In this large, population-based sample, the timing of adversity, distinguishing childhood from adulthood, shaped whether females or males showed stronger associations with biological ageing markers. These findings suggest that sex differences in biological ageing profiles may partly reflect distinct sensitive periods of vulnerability, highlighting the importance of considering both sex and timing of exposure to adversity when examining links between adversity and biological ageing.