Effect of short-term exposure to air pollution on hospital admission for cardiovascular disease: A time-series study in Xiangyang, China.

Background: Data on the relationship between short-term exposure to air pollution and cardiovascular diseases (CVDs) and the potential modifying factors are limited and inconsistent.

Objective: To explore the relationship between short-term exposure to air pollution and CVD risk, and potential modification effect factors.

Method: A time series study was conducted on 52,991 hospital admissions for CVD from 2015 to 2019 in Xiangyang City, China. Air pollution data from four national fixed monitoring stations were collected to estimate exposure level in Xiangyang City. A quasi-Poisson generalized additive model incorporating a distributed lag nonlinear model was applied to evaluate the association between air pollution and CVD risk. The potential modification effect of sex, age, and season on the above associations was also evaluated.

Results: CVD risk was positively associated with air pollution. Peak associations in single lag day structures were observed for particulate matter ≤10 μm in aerodynamic (PM; RR: 1.040, 95 % CI: 0.996-1.087), PM (1.025, 1.004-1.045), nitrogen dioxide (NO; 1.074, 1.039-1.111), and sulfur dioxide (SO; 1.079, 1.019-1.141) at Lag 0 and ozone (O; 1.018, 1.004-1.031) at Lag 4. In cumulative lag day structures, the highest RRs were 1.225 (1.079,1.392) for PM at Lag 06, 1.054 (1.013, 1.098) for PM at Lag 03, 1.200 (1.119, 1.287) for NO at Lag 04, and 1.135 (1.025, 1.257) for SO at Lag 02. Moreover, the association between air pollution and CVD risk was modified by sex and age (P < 0.05). Females and individuals aged ≤65 years were more vulnerable to NO and had a higher CVD risk.

Conclusion: Short-term exposure to air pollution was positively associated with CVD risk. Moreover, sex and age could modify the effect of air pollution on CVD risk. Females and individuals aged ≤65 years had a higher NO exposure-induced CVD risk.