Marital dissatisfaction and functional performance in older adults: Heterogeneity in the association by educational...

The marital relationship is an important source of the well-being of older adults. Despite existing literature on marital dissatisfaction and adverse health outcomes, little is known about whether marital dissatisfaction is associated with functional performance in older adults.

Drawing on stress process model and health behavior model, this study examined the longitudinal association between marital dissatisfaction and older adults' functional performance. Furthermore, we sought to investigate whether this association varies based on educational level.

Using seven waves (12 years) of the Korean Longitudinal Study of Ageing (KLoSA) from 2006 to 2019, this study estimated fixed effects models to account for unobserved individual-level confounders. Objectively measured hand grip strength and subjective assessments of vision, hearing, masticatory functions, as well as limitations in activities of daily living (ADLs) and instrumental activities of daily living (IADLs) were used to evaluate functional performance. An interaction model was used to determine whether educational level moderates the association.

Fixed effects estimates revealed that marital dissatisfaction is negatively associated with grip strength, as well as masticatory, vision, and hearing functions, while also showing a positive association with limitations in ADLs and IADLs. The results of this study provided evidence on heterogeneity in the association by educational level. The associations between marital dissatisfaction and functional performance, including grip strength, mastication, and hearing, were driven primarily by those with older adults with a higher level of education.

The findings of this study suggest that marital dissatisfaction is a robust predictor of functional performance in older adults. Efforts to address marital dissatisfaction has the potential to improve functional performance, particularly for older adults with higher levels of education.