Cognitive Impairment and Associated Factors among the Elderly in the Shanghai Suburb: Findings from a Low-Education Population

Objective: Our purpose was to investigate the prevalence of cognitive impairment and associated factors among elderly people in the Shanghai suburb. Methods: A population-based survey was conducted for people aged 60 years and over in a community of 2 towns (Huaxin and Xujing) in Qingpu district, located in the western suburb of Shanghai. Face-to-face interviews were carried out to collect relevant information with prepared questionnaires. The Chinese version of the Mini-Mental State Examination was used to screen subjects with cognitive impairment, and the criteria of cognitive impairment were adjusted for education level. Univariate and multivariate logistic regression analyses were performed to evaluate factors putatively associated with cognitive impairment. Results: There were 2,809 subjects (1,010 men and 1,799 women) aged 60 years and over (mean: 70.6, SD: 6.6) included in the study, and 198 people (42 men and 156 women) had cognitive impairment, with a prevalence of 7.0% (95% CI: 6.1–7.9) for both genders, 4.2% (95% CI: 3.6–4.8) for men and 8.7% (95% CI: 8.0–9.4) for women among the elderly. The prevalence rates of cognitive impairment increased with age. Although a number of factors were found to be significantly associated with the risk of cognitive impairment from the univariate analysis, only age (OR: 2.245, 95% CI: 1.755–2.872) and preferring a nonsalty diet (OR: 0.647, 95% CI: 0.460–0.912) were left in the final model of multivariate logistic regression analysis. Conclusion: The prevalence of cognitive impairment among the elderly in the Shanghai suburb is relatively high, compared with that previously reported from other areas in China, but lower than that from western countries. Factors associated with cognitive impairment need to be further investigated in the future.