Association of socioeconomic status and cognitive functioning change among elderly Chinese people

Background and Objective: the inverse association between high socioeconomic status and impaired cognitive functioning in old age has been widely studied. However, it is still inconclusive whether higher socioeconomic status slows the rate of cognitive decline over ageing, especially in non-Western populations. We examined this association using a large population-based longitudinal survey of older Chinese persons. Methods: the sample came from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) (from the years 2002 to 2011, N = 15,798 at baseline, aged 65-105). The Mini-Mental State Examination (MMSE) based on face-to-face interviews was used to assess cognitive functioning. Socioeconomic status was assessed using educational attainment and household income per capita. Latent growth curve and selection model considering the attrition during the follow-up were utilised to assess the effect of socioeconomic status on the rate of change in cognitive functioning. Results: at baseline, younger elderly people, urban residents and elderly people living alone had better cognitive performance in both genders. Educational attainment was positively associated with cognitive functioning at baseline but did not have a significant effect on the rate of change in cognitive functioning. Higher incomes were associated with better cognitive functioning at baseline, but this difference diminished during the follow-up. Conclusion: higher socioeconomic status was associated with better cognitive performance at baseline but could not protect against the rate of decline in cognitive functioning measured by MMSE in this longitudinal study for elderly Chinese people.