Cognitive Function and Impairment in Older, Rural South African Adults: Evidence from 'Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in Rural South Africa'

摘要

Background/Aims: We aimed to estimate the prevalence of cognitive impairment, and the sociodemographic and comorbid predictors of cognitive function among older, rural South African adults. Methods: Data were from a population-based study of 5,059 adults aged = 40 years in rural South Africa in 2015. Cognitive impairment was defined as scoring = 1.5 SDs below the mean composite time orientation and memory score, or requiring a proxy interview with "fair" or "poor" proxy-reported memory. Multiple linear regression estimated the sociodemographic and comorbid predictors of cognitive score, with multiplicative statistical interactions between each of age and sex with education. Results: Cognitive impairment increased with age, from 2% of those aged 40-44 (11/516) to 24% of those aged = 75 years (214/899). The independent predictors of lower cognitive score were being older, female, unmarried, not working, having low education, low household wealth, and a history of cardiovascular conditions. Education modified the negative associations between female sex, older age, and cognitive function score. Conclusions: The prevalence of cognitive impairment increased with age and is comparable to rates of dementia reported in other sub-Saharan African countries. Age and sex differences in cognitive function scores were minimized as education increased, potentially reflecting the power of even poor-quality education to improve cognitive reserve. (C) 2018 S. Karger AG, Basel