Association of PM _2.5 with hypertension, type 2 diabetes, and multimorbidity: evidence from the China Migrants Dynamic Survey of 165,075 individuals

This study aims to investigate the relations of exposure to ambient PM_2.5 with hypertension, type 2 diabetes, and multimorbidity among the Chinese mobile population. The study used the China Migrants Dynamic Survey (CMDS) data, PM_2.5 and Meteorological data in 2017. Binary logistic regression models were performed to examine the relationships between PM_2.5 and chronic diseases in mobile population after adjusting for covariates. Overall, each tertile increase in PM_2.5 was associated with increased odds of hypertension (OR = 1.047, 95% CI: 1.013-1.082), type 2 diabetes (OR = 1.095, 95% CI: 1.014-1.182) and multimorbidity (OR = 1.098, 95% CI: 1.005-1.199) in mobile population. Greater OR for association of PM_2.5 with multimorbidity than a single disease. Stratified analyses revealed that males were susceptible to PM_2.5-related hypertension and diabetes, and females were susceptible to PM_2.5-related multimorbidity. The older and people with low incomes were more likely to be affected by PM_2.5 to develop hypertension, type 2 diabetes, and multimorbidity. This study suggested that PM_2.5 was associated with hypertension, type 2 diabetes, and multimorbidity in Chinese mobile population. The elderly and those with low incomes mobile population were susceptible to PM_2.5. Effective strategies for air pollution reduction should be taken by local policymakers to further improve the migrants' health status.