Does Low Subjective Social Status Predict Cognitive Decline in Chinese Older Adults? A 4-Year Longitudinal Study From Hong Kong

Abstract

Objective: Subjective social status (SSS), one's self-perceived social position, encompasses not only concrete socio-economic (SES) factors (e.g., income) but also intangible aspects of status (e.g., social capital). In recent years, there has been increasing research interest in SSS as a predictor of a vast array of health outcomes but very few studies examining effects on cognitive functioning. This study's main objective was to examine the association between SSS and long-term cognitive decline in older Chinese adults.

Design: A 4-year longitudinal study.

Setting: Hong Kong, China.

Participants: Chinese adults (aged ≥65) (n = 3,153).

Measurements: This study analyzed baseline SSS-Hong Kong (self-perceived social status within Hong Kong) and SSS-Community (self-perceived status within one's own social network) as predictors of long-term cognitive decline. Multiple-linear-regression was performed on 4-year follow-up Mini-Mental-Status-Examination (MMSE) cognitive function score (score range: 0-30) after adjusting for baseline MMSE scores, traditional SES indicators (e.g., education), demographic variables (e.g., sex), clinical conditions (e.g., stroke history, depression), and lifestyle variables (e.g., physical activity levels).

Results: Lower SSS-Community but not SSS-Hong Kong was associated with greater cognitive decline (unstandardized coefficient (95% CI) = 0.13 (0.07, 0.19) standardized β-coefficient = 0.08, after adjusting for objective SES measures and other background and clinical factors. The standardized β-coefficients for the SSS-Community variable were similar in magnitude to those for depression and diabetes.

Conclusion: Cognitive decline is influenced by self-perceived rank in proximal reference groups rather than socioeconomic comparison with society at-large. SSS-Community is a useful, single-item supplementary instrument to improve prediction of cognitive decline in elderly Chinese.

Keywords: Chinese; Geriatrics; MMSE; dementia; epidemiology; social status.