Fine particulate air pollution and hospital visits for asthma in Beijing, China

- Link between PM2.5 and adult asthma in a Chinese city was studied.
- PM2.5 was associated with asthma-attributed outpatient and emergency room visits.
- A linear exposure-response relationship between PM2.5 and asthma was observed.

Data on fine particulate matter (PM2.5) in China were first announced in 2013. The primary objective of this study was to evaluate the acute effects of PM2.5 on asthma morbidity in Beijing, China. A total of 978,658 asthma hospital visits consisting of 928,607 outpatient visits, 40,063 emergency room visits and 9988 hospital admissions from January 1, 2010, to June 30, 2012, were identified from the Beijing Medical Claim Data for Employees. A generalized additive Poisson model was applied to explore the association between PM2.5 and health service use. The mean daily PM2.5 concentration was 99.5 μg/m3 with a range from 7.2 μg/m3 to 492.8 μg/m3. Ambient PM2.5 concentration was significantly associated with increased use of asthma-related health services. Every 10 μg/m3 increase in PM2.5 concentration on the same day was significantly associated with a 0.67% (95% CI, 0.53%-0.81%), 0.65% (95% CI, 0.51%-0.80%), and 0.49% (95% CI, 0.35%-0.64%) increase in total hospital visits, outpatient visits and emergency room visits, respectively. The exposure-response association between PM2.5 concentration and hospital visits for asthma exacerbations was approximately linear. In conclusion, this study found that short-term elevations in PM2.5 concentration may increase the risk of asthma exacerbations. Our findings contribute to the limited scientific literature concerning the acute effects of PM2.5 on asthma morbidity outcomes in developing countries.

The exposure-response curve of 3-day (lag0-2) moving average fine particulate matter (PM2.5) concentrations and hospital visits for asthma between January 1, 2010, and June 30, 2012, in Beijing, China. Note: The X-axis is the 3-day (lag0-2) moving average PM2.5 concentrations (μg/m3). Y-axis is the predicted log (relative risk (RR)), after adjusting for temperature, relative humidity, day of week, public holiday, and calendar time, is shown by the solid line, and the dotted lines represent the 95% CI.80