Short‐Term Exposure to Ambient Air Pollution and Hospitalization Risks and Costs on Type 2 Diabetes With Three Typical Comorbidities in Sichuan, China: A Time‐Stratified Case‐Crossover Study

This study is aimed at examining the associations and hospitalization costs between air pollutants and hospital admissions (HAs) for type 2 diabetes mellitus (T2DM) with three typical comorbidities, namely cardiovascular disease (CVD), hypertension, and peripheral vascular disease (PVD). Conditional Poisson regression based on Poisson distribution was used to confirm the relationship between air pollution and HAs for T2DM with comorbidities. Potential effect modifiers, such as age and gender, were also involved. The attributable hospitalization number and costs due to air pollutants exposure were estimated, using WHO's air quality guidelines as reference. In total, 92,381 T2DM HAs were recorded, of which 6,855 patients with CVD, 23,403 with hypertension, and 21,207 with PVD, respectively. The significant short‐term effects of NO 2 , PM 10 , PM 2.5 and SO 2 on HAs for T2DM with CVD, hypertension and PVD were different, mainly concentrated on lag 6 and lag 7. Stratified analysis demonstrated that mainly female and elder people (≥45 years) were more vulnerable to air pollutants. Total hospitalization costs attributable to air pollution were substantial. For T2DM patients with CVD, the hospitalization costs linked to NO 2 , PM 10 , and PM 2.5 were 7.43, 3.04, and 6.79 million China Yuan (CNY), respectively. For the hypertension comorbidity group, costs reached 12.17 million CNY for NO 2 and 10.89 million CNY for PM 10 . Additionally, NO 2 exposure for 10.82 million CNY in hospitalization costs for T2DM patients with PVD. These findings underscore that air pollution not only exacerbates health risks but also imposes a significant financial strain on the healthcare system for vulnerable populations.