Grandparent caregiving and epigenetic aging among midlife and older adults in the United States

ObjectivesGrandparents have increasingly taken more active caregiving roles for grandchildren. Given their vulnerability to aging-associated health declines, it is essential to understand how grandparent caregiving, along with grandparent gender and family relationships, may influence aging processes. This study examined how grandparent caregiving status interacts with gender and family affectual solidarity (FAS) to affect epigenetic aging, an indicator of healthspan and mortality risk.MethodsOur sample included grandparents participating in the Midlife in the United States (MIDUS) study (N = 492; mean age = 61.94; female = 59.96%), 18.29% of whom reported being grandparent caregivers for 6+ months. Epigenetic age was measured using the Horvath, Hannum, PhenoAge, GrimAge, and DunedinPACE epigenetic clocks. We tested for moderation by gender and FAS, the degree of positive (and negative) sentiment between family members.ResultsLinear regression found, controlling for sociodemographic characteristics and BMI, associations between grandparent caregiving and DunedinPACE, indicating that more time spent caring for grandchildren is related to a faster pace of aging. Two-way interactions between grandparent caregiving and gender showed epigenetic age acceleration (higher biological age compared to chronological age) for grandfather caregivers versus non-caregiving grandfathers across multiple clocks. Three-way interactions between grandparent caregiving, gender, and FAS indicated that caregiving grandfathers experience epigenetic age deceleration with higher FAS compared to caregiving grandmothers. Similarly, caregiving grandfathers experience epigenetic age deceleration with higher partner affectual solidarity compared to caregiving grandmothers.DiscussionThese results have implications for targeted interventions to benefit the healthy aging of grandparent caregivers.