Relationship stress and epigenetic age acceleration among older U.S. adults in the Midlife in the United States study.

BACKGROUND

Chronic interpersonal stress has been linked to accelerated biological aging, but questions remain about which relationship stress domains may be most consequential during midlife.

RESEARCH DESIGN AND

METHODS

Linear regression models quantified the cross-sectional associations between domain-specific relationship stressors (marital risk, partner strain, family strain, friendship strain) and next-generation epigenetic clocks (DunedinPACE and GrimAge2) in 1,310 midlife adults from the Midlife in the United States study (mean age = 51, SD = 13).

RESULTS

Controlling for sociodemographic and health behaviors, we found that friendship strain was uniquely associated with accelerated aging (GrimAge2: 0.03 SD increase, 95% CI: 0.01, 0.05, p = 0.003; DunedinPACE: 0.05 SD increase, 95% CI: 0.01, 0.09, p = 0.030). No statistically significant associations were observed for the other stressors with GrimAge2 or DunedinPACE in fully adjusted models.

CONCLUSIONS

These findings identify friendship strain as a potential specific risk factor for accelerated biological aging in midlife. Future research should investigate behavioral and physiological mechanisms linking friendship quality to cellular aging.