Frailty and socioeconomic stratification in Brazil, India, and China

We examine the association between social determinants of health (SDoH) and the health of older adults in three countries experiencing rapid economic growth: Brazil, India, and China. We assessed health using frailty, the vulnerability to poor recovery after a physiologic stressor. We created a frailty index with data from three health and retirement surveys: the Brazilian Longitudinal Study of Aging wave 1 (2015–2016), the China Health and Retirement Longitudinal Survey wave 3 (2015–2016), and the Longitudinal Aging Study in India wave 1 (2017–2019). SDoH measures included within-country income and wealth deciles, education level, and rural residence. We analyzed data using beta regression, first within country, then with merged data with interactions between country and each SDoH, and finally with the merged analysis stratified by age. Both within country and with merged data, education was consistently the SDoH most strongly and significantly associated with frailty, with higher education tied to lower frailty. These associations attenuated with greater age. We show first that education has associations with health into older age and second the value of cross-national comparisons for understanding drivers of the health of older adults.