Marital transition and cognitive function among older adults: the korean Longitudinal Study of Aging (2006–2020)

BACKGROUND: Marital status has been suggested as an associated factor for cognitive impairment. The consequences of marital transitions are still understudied. This study evaluated the influence of marital transitions on cognitive function using longitudinal, nationwide data of Korean older adults. METHODS: This research comprised a longitudinal sample of older adults aged ≥ 45 years old, drawn from the Korean Longitudinal Study of Aging (2006–2020). Marital transition was determined through the biennial assessment of change in marital status; cognitive function was measured using the Korean version of the Mini-Mental State Examination. We employed general estimating equations to assess the temporal effect of marital transition on cognitive function. RESULTS: Compared to married individuals, the odds ratios (ORs) of cognitive decline were higher in not married and transitioned out of marriage participants: men (OR 1.32, 95% confidence interval (CI) 0.96–1.82; OR 1.42, 95% CI 0.90–2.24), women (OR 1.21, 95% CI 1.03–1.42; OR 1.20, 95% CI 1.01–1.52), respectively, despite the findings being not statistically significant in men. The participants who transitioned out of marriage over time also showed greater ORs for mild cognitive impairment: men (OR 1.39, 95% CI 0.79–1.87), women (OR 1.33, 95% CI 1.05–1.80), and dementia: men (OR 1.60, 95% CI 0.85–1.99), women: (OR 1.49, 95% CI 1.20–2.19). CONCLUSION: Marital transition is found to be associated with cognitive function decline. Not-married individuals and those who became divorced or widowed were associated with the risk of cognitive function decline. Particular attention should be paid to these marital transitioned groups. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12877-022-03697-x.