Ambient air pollution and hospital visits for peptic ulcer disease in China: A three-year analysis

Background: Peptic ulcer disease (PUD) continued to be a source of significant morbidity and mortality worldwide. Recently, it has been reported that exposure to air pollution is a potential risk factor for PUD, but evidence on the association still remains inconsistent. Methods: We performed an ecological study to examine the association between short-term exposure to air pollution and daily hospital visits for PUD in Yinzhou, China from January 1st, 2017 to December 31st, 2019. Distributed lag nonlinear models were used to estimate the nonlinear and lag-response effects of air pollutants. Subgroup analyses stratified by sex, age and season were conducted to examine the effect modifications. Results: Overall, we found that short-term exposure to air pollution including SO2, NO2, CO, O3 and PM2.5 was significantly associated with hospital visits for PUD among all subjects. The lag-response effects of SO2, NO2 and O3 varied at different concentrations and lag days. The cumulative risk ratios of CO and PM2.5 showed nearly linear adverse effects and increased to maxima of 2.68 (95% CI: 1.49–4.78) and 2.40 (95% CI: 1.36–4.24) with their ranges from the references to the maximum concentrations, respectively. Moreover, the cumulative risks of particulate matters on hospital visits for PUD increased significantly in cold seasons, but not in warm seasons. Conclusions: Our findings could provide growing evidence regarding the adverse health effects of air pollution on PUD, thereby strengthening the hypothesis that air pollutants have harmful impacts on digestive system.