Associations of short-term exposure to air pollution with outpatient visits and treatment costs for chronic obstructive pulmonary disease in Xinxiang, China (2016-2021)

The acute health effects of air pollution on the risk of chronic obstructive pulmonary disease (COPD) have not been adequately studied and results remain inconsistent. Furthermore, fewer studies have explored the impact of air pollution on the cost of treating patients with COPD. Generalized additive models (GAM) based on Poisson distribution and gamma were applied to evaluate the association between short-term exposure to air pollution and daily COPD outpatient visits and daily COPD treatment costs. A total of 14,611 outpatient in Xinxiang from 2016 to 2021 were included for analysis. We found that short-term exposure to PM_2.5, PM₁₀, NO₂ and CO were positively associated with COPD outpatient visits, and gaseous pollutants appeared to have greater effects on outpatient visits than particulate matter. For the largest effect, per 10 μg/m³ increment in (per 1 mg/m³ increment in CO concentration) CO (lag 01), NO₂ (lag 01), PM_2.5 (lag 02) and PM₁₀ (lag 06) were significantly associated with 7.859 % (95 % CI:3.421,12.488), 4.894 % (95 % CI:3.422,6.386), 0.627 % (95 % CI:0.010, 1.248) and 0.531 % (95 % CI:0.050,1.014) increase in daily COPD outpatient visits, respectively. Short-term exposure to air pollutants (PM₁₀, CO and NO₂) was positively associated with COPD treatment costs. No significant sex or age differences were found in the stratified analysis of outpatient visits. The effect of gaseous pollutants (NO₂) on COPD outpatient visits was greater in the cold season (October to March) (P < 0.05), whereas the effect of particulate matter (PM_2.5 and PM₁₀) was greater in the warm season (April to September) (P < 0.05). Greater health benefits could be obtained when pollutant concentrations meet WHO standards. In conclusion, short-term exposure to PM_2.5, PM₁₀, NO₂ and CO was significantly associated with increased COPD outpatient visits, and gaseous pollutants appeared to have greater effects on outpatient visits than particulate matter. Further larger-scale studies are needed to validate our findings.