The increased medical burden associated with frailty is partly attributable to household solid fuel: A nationwide prospective study of middle-aged and older people in China

Frail individuals often face a high medical burden, and household solid fuel use is associated with a range of functional declines or diseases, but evidence on the relationship between household solid fuel and frailty and the resulting medical burden is limited. We aim to investigate the effect of household solid fuel on frailty and further quantify how much of the increased medical burden associated with frailty is attributable to household solid fuel.The prospective data were from the China Health and Retirement Longitudinal Study, 4685 non-frail participants at baseline were included. Inverse probability weighting was used to balance the covariates between groups. The modified Poisson regression was used to analyze the association of household solid fuel (including baseline and switching across three-wave survey) with frailty, and the generalized linear model was used to analyze the association of frailty with the change in medical burden. Further, the increased medical burden associated with frailty attributable to household solid fuel was quantified.Using solid fuel for cooking (RR = 1.29, 95%CI, 1.07-1.57), heating (RR = 1.38, 95%CI, 1.09-1.73), or both (RR = 1.40, 95%CI, 1.05-1.86) had a higher risk of frailty than using clean fuel. In addition, the risk of frailty generally increases with the times of solid fuel use across the three-wave survey. Then, frailty participants had a greater increase in the annual number of hospitalizations (β = 0.11, 95%CI, 0.02-0.19) and annual costs of hospitalizations (β = 2953.35, 95%CI, 1149.87-4756.83) than those non-frailty. Heating coal caused the largest frailty-related increase in the annual number of hospitalizations and annual costs of hospitalizations, with 0.04 and 1195.40, respectively.The increased medical burden associated with frailty was partly attributable to household solid fuel, which suggested that intervention targeting household solid fuels can delay frailty and thus reduce individual medical burden.