Influencing factors of mild cognitive impairment among the Chinese elderly: a meta-analysis

Abstract

Objective: To conduct a meta-analysis on the influencing factors of mild cognitive impairment (MCI) in the Chinese elderly. Methods: The literature related to the influencing factors of MCI in Chinese elderly population was retrieved through CNKI, Wanfang, VIP, PubMed, Embase and Web of Science databases up to March 13, 2022. Stata17.0 software was used to calculate the combined risk ratio (RR) with the 95% confidence interval (CI), test the heterogeneity, and assess the publication bias. Results: A total of 2 450 articles were retrieved, and 49 articles met the inclusion criteria, including 5 cohort studies and 44 case-control studies. Meta-analysis results showed that male (RR=0.778, 95%CI: 0.696-0.870, I2=73.1), education>6years (RR=0.428, 95%CI: 0.374-0.490, I2=86.9) and regular exercise (RR=0.496, 95%CI: 0.421-0.585, I2=81.5) were protective factors for MCI, while age≥70 years (RR=2.431, 95%CI: 2.086-2.833, I2=79.3), family history of dementia (RR=3.228, 95%CI: 2.140-4.867, I2=0.0), smoking (RR=1.214, 95%CI: 1.098-1.342, I2=78.8), alcohol consumption (RR=1.165, 95%CI: 1.047-1.297, I2=68.2), solitary living (RR=2.816, 95%CI: 2.123-3.736, I2=42.0), insomnia (RR=1.402, 95%CI: 1.093-1.799, I2=41.3), overweight/obesity (RR=1.431, 95%CI: 1.207-1.696, I2=75.9), hypertension (RR=1.731, 95%CI: 1.589-1.886, I2=67.1), hyperlipidemia (RR=1.722, 95%CI: 1.541-1.924, I2=63.9), diabetes mellitus (RR=1.495, 95%CI: 1.341-1.666, I2=71.6), cardiovascular diseases (RR=1.671, 95%CI: 1.446-1.932, I2=74.6) and cerebrovascular diseases (RR=2.309, 95%CI: 2.040-2.613, I2=76.3) were risk factors of MCI. Conclusion: The present study indicates that male, junior high school education or above and regular exercise are protective factors of MCI, while age≥70 years, family history of dementia, smoking, alcohol consumption, living alone, insomnia, overweight/obesity, hypertension, hyperlipidemia, diabetes, cardiovascular diseases and cerebrovascular diseases are risk factors of MCI.