Network outcome analysis of cognitive function and daily functioning and risk of dementia among adults aged 50 years and older: an 8-year prospective study.

BACKGROUND: Pre-existing cognitive dysfunction and poor daily functioning are associated with the risk of developing dementia. However, the associations of specific cognitive domains and daily functioning with the incidence of dementia remain inadequately studied. This study examined the associations of cognitive function and daily functioning with subsequent development of dementia among older Chinese adults over an eight-year follow-up period. METHOD: The study was based on the China Health and Retirement Longitudinal Study Life History Survey (CHARLS) data from 2013 to 2020. Cognitive function was assessed across executive function and episodic memory domains. Daily functioning was measured with five items adapted from the Instrumental activities of daily living (IADL) scale. The outcome was incident dementia identified during the follow-up period. Generalized logistic model and network outcome analysis were performed to examine the associations of specific cognitive functions and daily functioning with incident dementia. RESULT: Among 9182 participants included in the study, the incidence of dementia was 5.3% during the follow-up period. Both decreased cognitive function [OR: 0.95 (95% CI: 0.92-0.99)] and daily functioning [OR: 0.70 (95% CI: 0.64-0.77)] at baseline were associated with increased risk of dementia. The network outcome analysis indicated that IADL2 (preparing hot meals), IADL5 (taking medicine), episodic memory, and IALD3 (shopping) negatively predicted subsequent development of dementia. CONCLUSION: Older adults with decreased cognitive function and daily functioning have an increased risk of dementia in later life. Appropriate interventions to address IADL2, IADL3, IADL5 and episodic memory function may be potentially useful in reducing the risk of dementia.