Health and economic impacts of ambient air pollution on hospital admissions for overall and specific cardiovascular diseases in Panzhihua, Southwestern China

Background The associations of ambient air pollution with hospital admissions (HAs) for overall and specific causes of cardiovascular diseases (CVDs), as well as related morbidity and economic burdens remain understudied, especially in low-pollution areas of low- and middle-income countries (LMICs). We evaluated the short-term effects of exposure to PM2.5 (particles with an aerodynamic diameter <= 2.5 mu m), PM10 (particles with an aerodynamic diameter <= 10 mu m), and SO2 (sulfur dioxide) on HAs for CVDs in Panzhihua, China, during 2016-2020, and calculated corresponding attributable risks and economic burden. Methods We used a generalized additive model (GAM) while controlling for time trends, meteorological conditions, holidays, and days of the week to estimate the associations. The cost of illness (COI) method was adopted to further assess corresponding hospitalization costs and productivity losses. Results A total of 27 660 HAs for CVDs were included in this study. PM10 and SO2 were significantly associated with elevated risks of CVDs hospitalizations. Each 10 mu g/m(3) increase in PM10 and SO2 at lag06 corresponded to an increase of 2.48% (95% confidence interval (CI) = 0.92%-4.06%), and 5.50% (95% CI = 3.09%-7.97%) in risk of HAs for CVDs, respectively. The risk estimates of PM10 and SO2 on CVD hospitalizations were generally robust after adjustment for other pollutants in two-pollutant models. We found stronger associations between air pollution (PM10 and SO2) and CVDs in cool seasons than in warm seasons. For specific causes of CVDs, significant associations of PM10 and SO2 exposure with cerebrovascular disease and ischaemic heart disease were observed. Using 0 mu g/m(3) as the reference concentrations, 11.91% (95%CI = 4.64%-18.56%) and 15.71% (95%CI = 9.30%-21.60%) of HAs for CVDs could be attributable to PM10 and SO2, respectively. During the study period, PM10 and SO2 brought 144.34 million Yuan economic losses for overall CVDs, accounting for 0.028% of local GDP. Conclusions Our results suggest that PM10 and SO2 exposure might be an important trigger of HAs for CVDs and accounted for substantial morbidity and economic burden.