Association between ambient air pollution exposure levels and the risk of developing pulmonary embolism in the Chinese population: findings from the Chinese Cardiovascular Association (CCA) Database–Chest Pain Centre

Objective To analyse the associations between exposure to different air pollutants and the morbidity of pulmonary embolism (PE). Design Time series study with a distribution lag non-linear model. Setting 275 cities in China, 1 January 2015 to 31 March 2022. Participants 27 369 cases of PE. Main outcome measures The associations between exposure to different air pollutants and the morbidity of PE. Results During the study period, 27 369 cases of PE were recorded. PM 2.5 (Particulate Matter 2.5), PM 10 (Particulate Matter 10) and NO 2 (Nitrogen Dioxide) exposure levels were associated with an increased risk of developing PE in the single-pollutant model. PM 2.5 exposure caused the greatest risk of developing PE at lag 1 in the single-day lag model, with a relative risk (RR) value of 1.033 (95% CI 1.007 to 1.058). PM 10 and NO 2 exposure had the greatest effects at lag 0, with RR values of 1.038 (95% CI 1.016 to 1.059) and 1.039 (95% CI 1.009 to 1.068), respectively. No associations were found between CO(Carbon Monoxide), O 3 (Ozone) or SO 2 (Sulfur Dioxide) exposure levels and the risk of developing PE. PM 2.5 , PM 10 and NO 2 exposure levels were most strongly associated with the development of PE at lag 01 in the cumulative lag model, with RR values of 1.052 (95% CI 1.009 to 1.095), 1.053 (95% CI 1.020 to 1.086) and 1.058 (95% CI 1.005 to 1.111), respectively. Conclusions Short-term exposure to PM 2.5 , PM 10 and NO 2 can increase the risk of developing PE, especially in females. The effects of PM 2.5 and PM 10 exposure were more significant in cold seasons and in North China.