Education, occupation, and multimorbidity as determinants of domain-specific cognitive performance in community-dwelling older adults: a cross-sectional study

Background Although multimorbidity burden has been associated with cognitive decline in individuals with dementia, its role in cognitive aging remains unclear when cognitive reserve is considered. The objective of this study was to examine the independent and interactive effects of chronic disease burden and cognitive reserve—indexed by education and occupation—on domain-specific cognitive performance in older adults. Methods A cross-sectional study was conducted among 170 community-dwelling volunteers aged 60–80 years in Hualien County during 2014–2018, Taiwan. Multimorbidity burden was assessed using the Cumulative Illness Rating Scale for Geriatrics. Cognitive function was evaluated across five domains—attention, visual perception, executive function, language, and learning/memory—using standardized neuropsychological tests. Multiple linear models were used to analyze associations. Results Higher educational attainment was consistently associated with better performance across all cognitive domains. Managerial/professional occupational history predicted enhanced attention, language, and learning/memory. No significant associations were found between multimorbidity burden and overall cognitive performance. However, multimorbidity was negatively associated with visual perception among individuals with lower education. Conclusions Education emerged as the strongest predictor of cognitive performance. While multimorbidity had minimal overall impact, its adverse effect on visual perception was evident in those with limited education. These findings underscore the protective role of cognitive reserve and the importance of lifelong cognitive engagement and chronic disease management in promoting healthy cognitive aging.