Functional and Mental Health Outcomes of the Joint Effects of Spousal Health: The Potential Threats of "Concordant Frailty"

Objectives: Existing studies have indicated that caring for a person with disabilities in a family could result in strong adverse impacts on the health of his or her spouse. However, little is known about the potential joint burden and interactive patterns in a family when both spouses are in poor health. The objective of this study was to evaluate the impacts of self and spousal health statuses on the physical and mental health outcomes of older people in Taiwan.

Design: Retrospective observational study.

Setting: The Social Environment and Biomarkers of Aging Study (SEBAS), Taiwan.

Participants: Data of 1123 study participants from the SEBAS were retrieved for analysis and all participants were divided into 4 groups based on their self-rated and spousal health status: good self-good spousal health (GG), good self-poor spousal health (GP), poor self-good spousal health (PG), and poor self-poor spousal health (PP).

Measurements: Multinomial logistic regression models were used to evaluate the associations of the different health statuses of couples to disabilities of physical function, daily activity disabilities (activities of daily living, or ADLs, and instrumental activities of daily living, or IADLs) and depressive symptoms. Subgroup analyses were conducted for middle-aged (aged 53 to 64) and older (aged 65 and older) adults to examine whether the impacts of spousal health statuses on the physical and mental health outcomes increased with age.

Results: The adjusted multinomial logistic regressions showed that people in the PP group were at the highest risk for difficulties in physical function, daily activities, and depressive symptoms. This association was more significant in the elderly population than the middle-aged group. Elderly PP couples were associated with a 7-fold increase in risk of acquiring a disability of physical function (adjusted odds ratio [aOR] 7.5, 95% confidence interval [CI] 2.4-23.6, P < .01), an 8-fold increase in risk of an IADL disability (aOR 8.5, 95% CI 4.1-17.5, P < .01), a 47-fold increase in risk of an ADL disability (aOR 47.3, 95% CI 5.8-387.7, P < .01), and a 10-fold increase in risk of depressive symptoms (aOR 10.6, 95% CI 4.8-23.4, P < .01), compared with the elderly GG groups.

Conclusion: This is the first study to demonstrate that when both people in a couple have poor health status, it is a significant risk factor regarding difficulties in physical activities, daily activity disabilities, and depressive symptoms. This effect was particularly stronger in elderly couples compared with middle-aged couples.