Poverty increases the risk of incident cognitive impairment among older adults: a longitudinal study in China

Abstract

Objectives: With a longitudinal design, we aimed to investigate the relationship between poverty and the risk of incident cognitive impairment in China.Methods: We used three waves of the Chinese Longitudinal Healthy Longevity Survey (2008–2014). Cognitive impairment was assessed using the Chinese version of the Mini Mental State Examination. Poverty was measured according to the latest national poverty line settled at an annual per-capita income of 2300 yuan (approximately equivalent to 1.25 dollar/day) in 2011 in China. A marginal structural model was utilized to explore the association between poverty and the risk of incident cognitive impairment. The subgroup analyses were also conducted in this study.Results: The cumulative incidence of cognitive impairment over 6 years was 30.69% (1936/6309). Poverty increased 34% risk of incident cognitive impairment in the elderly (odds ratio = 1.34, 95% confidence interval (CI): 1.15–1.56) after controlling behavioral factors and health status covariates. Participants who were male (OR = 1.38, 95% CI: 1.08–1.76), lived in urban areas (OR = 1.55, 95% CI: 1.22–1.98), and were married (OR = 1.72, 95% CI: 1.28–2.32) had higher poverty risks on incident cognitive impairment in subgroup analyses.Conclusions: Our results provide empirical support for the ongoing discussion about how economic hardship impacts of cognitive functioning, and highlight the negative health risks that economically disadvantaged individuals may experience.