Cognitive Decline and It’s Risk Factors in the Elderly in China: A Longitudinal Study

Abstract Background Cognitive decline，a prodromal symptom of Mild Cognitive Impairment (MCI) and Alzheimer's disease (AD) with no effective treatment, often occurs in the elderly. Prevent the occurrence of diseases by controlling risk factors is the best way to reduce its harms. The aim of this study was to identify the influencing factors of the cognitive function decline. Methods This study included analyzed 4482 participants obtained from the China Health and Retirement Longitudinal Study (CHARLS). Generalized estimating equation (GEE) model was used to analyze the factors affecting the decline of cognitive function level of the elderly.Results According to this study, being female (OR 1.39), older (OR 1.34 to 5.73 from group 65~69 years to group age≥80 years), unmarried/divorced/widowed (OR 1.41), lower education (OR 2.37 to 45.36 from junior high school graduation to illiteracy), living in a rural area before 16 years (OR 1.87), keep smoking (OR 1.26), over napping (OR 1.28), underweight (OR 1.73), having difficulties with everyday activities (OR 1.25), and poor self-rated health (OR 1.36) were at higher risk of cognitive function decline in the elderly. While drinking once a month and above (OR 0.80), taking care of grandchildren in the last year (OR 0.71), overweight (OR 0.73), and obese (OR 0.63) were the protective factors. Conclusion Cognitive decline in the elderly was associated with several risk factors. Thus, future research should be focused on high risk elderly with these predictive factors, both to delineate mechanisms for development of cognitive decline and to evaluate preventive interventions.