Factors affecting cognitive function in older adults: a sex-specific analysis using panel quantile regression

The aging population has significantly increased in South Korea because of the factors such as longer life expectancy and lower birth rate. Healthy aging requires to preserve the cognitive function. Cognitive decline can hinder daily independent living. It is imperative to understand determinants of cognitive function in older adults for formulating effective interventions and policies. This study analyzed the data of Korean Longitudinal Study of Aging (KLoSA) from 2006 to 2020. A total of 4001 participants (1695 men and 2306 women) aged 65 and older were included in the final analysis. The sex-specific differences in cognitive function were assessed using statistical analyses including panel regression and panel quantile regression. Cognitive function had significant difference between men and women. Men showed higher cognitive function scores than women. Both men and women depicted significant influence on cognitive function based on age, employment status and depression. These factors had varying effects depending on the cognitive function level. Men’s age, working status, and depression were associated with dementia regardless of cognitive function, whereas women’s factors were more pronounced with low cognitive function. This study emphasizes the tailored sex-specific interventions and policies to improve cognitive function in older adults by considering sex-specific differences and varying cognitive function levels.

Cognitive function; Older adults; Sex-specific analysis; Panel quantile regression

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