Association of depressive symptoms and dementia among middle-aged and elderly community-dwelling adults: Results from the China Health and Retirement Longitudinal Study (CHARLS).

Background: There has been a long-standing debate on whether depressive symptoms are associated with dementia. The aim of this study was to examine whether depressive symptoms were associated with a high risk for dementia in Chinese adults.

Methods: A total of 13,426 Chinese adults (≥45 years old) from the China Health and Retirement Longitudinal Study (CHARLS) baseline were selected for analysis. Depressive symptoms were assessed by the Center for Epidemiologic Studies Depression Scale (CESD-10). Dementia was assessed by the Community Screening Instrument for Dementia (CSI-D). When using linear regression for sensitivity analysis, there is still a correlation between depressive symptoms and dementia.

Results: Of the 13,426 respondents, the mean (SD) age was 60 (10) years old. The prevalence of depressive symptoms and dementia among participants was 38 % (n = 945) and 18.3 % (n = 2457), respectively. After fully adjusted for demographic factors, health behavior and psychological factors, living and working conditions factors, social network factors, and social policy factors, the cross-sectional analyses showed that depressive symptoms had an increased risk of dementia (OR = 1.390, 95%CI: 1.253-1.543), compared with those without depressive symptoms. In addition, sensitivity analyses of the association between depressive symptoms and dementia were unchanged when reanalyzing using linear regression.

Conclusions: In this study, depression symptoms may be associated with dementia. Regardless of whether depressive symptoms acts as a dementia risk factor or an early symptom, monitoring depressive symptoms is crucial to watch for potential dementia onset.