Associations between air pollutants and hospital admissions for chronic obstructive pulmonary disease in Jinan: potential benefits from air quality improvements

Evidence between air pollution and chronic obstructive pulmonary disease (COPD) is inconsistent and limited in China. In this study, we aim to examine the associations between air pollutants and hospital admissions for COPD, hoping to provide practical advice for prevention and control of COPD. Hospital admissions for COPD were collected from a Grade-A tertiary hospital in Jinan from 2014 to 2020. A generalized additive model (GAM) was used to examine the associations between air pollutants and hospital admissions for COPD. Stratified analysis was also conducted for gender, age (20-74 and >= 75 years), and season (warm and cold). The avoidable number of COPD hospital admissions was calculated when air pollutants were controlled under national and WHO standards. Over the study period, a total of 4,012 hospital admissions for COPD were recorded. The daily hospital admissions of COPD increased by 2.36% (95%CI: 0.13-4.65%) and 2.39% (95%CI: 0.19-4.65%) for per 10 mu g/m(3) increase of NO2 and SO2 concentrations at lag2, respectively. There was no statistically significant difference in health effects caused by increased concentrations of PM2.5, PM10, CO, and O-3. The health effects of increased SO2 concentration were stronger in women, the >= 75 years old people and the cold season. About 2 (95%CI: 0-3), 64 (95%CI: 4-132) and 86 (95%CI: 6-177) COPD admissions would be avoided when the SO2 concentration was controlled below the NAAQS-II (150 mu g/m(3)), NAAQS-I (50 mu g/m(3)), and WHO's AQG2021 standard (40 mu g/m(3)), respectively. These findings suggest that short-term exposure to NO2 and SO2 was associated with increased risks of daily COPD admissions, especially for females and the elderly. The control of SO2 and NO2 under the national and WHO standards could avoid more COPD admissions and obtain greater health benefits.