Caregiving and all-cause mortality in postmenopausal women: Findings from the Women's Health Initiative

Background: Caregiving is commonly undertaken by older women. Research is mixed, however, about the impact of prolonged caregiving on their health, well-being, and mortality risk. Using a prospective study design, we examined the association of caregiving with mortality in a cohort of older women.

Methods: Participants were 158,987 postmenopausal women aged 50-79 years at enrollment into the Women's Health Initiative (WHI) who provided information on current caregiving status and caregiving frequency at baseline (1993-1998) and follow-up (2004-2005). Mortality was ascertained from baseline through March of 2019. Cox regression with caregiving status defined as a time-varying exposure was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for mortality, adjusting for sociodemographic factors, smoking, and history of diabetes, hypertension, cardiovascular disease (CVD), and cancer. Stratified analyses explored whether age, race-ethnicity, depressive symptoms, frequency of caregiving, optimism, and living status modified the association between caregiver status and mortality.

Results: At baseline, 40.7% of women (mean age 63.3 years) self-identified as caregivers. During a mean 17.5-year follow-up, all-cause mortality (50,526 deaths) was 9% lower (multivariable-adjusted HR = 0.91, 95% CI: 0.89-0.93) in caregivers compared to non-caregivers. The inverse association between caregiving and all-cause mortality did not differ according to caregiving frequency or when stratified by age, race-ethnicity, depressive symptoms, optimism, or living status (interaction p > 0.05, all). Caregiving was inversely associated with CVD and cancer mortality.

Conclusion: Among postmenopausal women residing across the United States, caregiving was associated with lower mortality. Studies detailing the type and amount of caregiving are needed to further determine its impact on older women.