Trends in the Prevalence of Cognitive Impairment Among Older Adults Aged 65 to 105 Years — China, 2002–2018

Abstract

<abstract abstract-type="Abstract"> <sec> <b>Introduction</b> This study aims to analyze trends and subgroup differences in the prevalence of cognitive impairment among older Chinese adults aged 65–105 years from 2002 to 2018. </sec><sec> <b>Methods</b> Data were drawn from six waves of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Cognitive function was measured using the Chinese version of the Mini-Mental State Examination (CMMSE). Cognitive impairment was determined by the total CMMSE score and educational attainment of participants. The generalized estimating equation (GEE) models with a logistic link and binominal distribution were performed to assess the secular trend in the prevalence. </sec><sec> <b>Results</b> The prevalence of cognitive impairment among older adults aged 65–105 years decreased from 3.44% [95% confidence interval (CI): 3.15%–3.73%] in 2002 to 2.41% (95% CI: 2.17%–2.65%) in 2018 in China. The prevalence was slightly higher in women than in men in 2002 (3.71% <i>vs</i>. 3.13%, <i>P</i>&lt;0.05), and there was no significant difference between women and men in 2018 (2.60% <i>vs</i>. 2.21%, <i>P</i>=0.12). Rural older adults had a higher prevalence of cognitive impairment before 2014, but their urban counterparts had a higher prevalence in 2018 (2.75% <i>vs</i>. 2.06%, <i>P</i>&lt;0.05). The GEE regression model showed that each successive year was associated with a 3% reduction in the odds of the prevalence of cognitive impairment [odds ratio (OR)=0.97; 95% CI: 0.97–0.97; <i>P</i>&lt;0.05]. </sec><sec> <b>Conclusions</b> The prevalence of cognitive impairment among Chinese older adults aged 65–105 years declined slowly from 2002 to 2018. The gender, urban-rural, age, and regional differences in the prevalence of cognitive impairment changed over time. </sec>