Short-term exposure to coarse particulate matter and outpatient visits for cardiopulmonary disease in a Chinese city.

Limited studies have been conducted to evaluate the short-term relationships between exposure to coarse particulate matter (PM) and outpatient visits in China. We designed this time-series analysis in a Chinese city Yancheng, to explore the relationship of PM with outpatient visits for cardiopulmonary diseases. The study period was from 2013 to 2015. A typical generalized additive model was used. We explored the lag patterns by building a series of lag of exposure. We also built two-pollutant models to ascertain the independence of PM. Stratified analyses were applied to compare the season-specific associations. Finally, we pooled the concentration-response (C-R) curves for PM and outpatient visits. We recorded a daily average of 85 and 43 outpatient visits for cardiovascular and respiratory causes, respectively. PM exposures of lag 05 day yielded the best estimates for both outcomes. Per 10-μg/m increase in PM, there was a 1.69% (95% confidence interval [CI]: 0.68%-2.72%) increase in outpatient visits for respiratory causes, and a 0.85% (95% CI: 0.13%-1.57%) increase for cardiovascular causes. The association kept robust after adjusting for PM and O, and there were larger associations in warm seasons. The C-R curves had a larger slope for respiratory diseases in relatively lower concentrations (<30 μg/m), and PM was positively associated with cardiovascular diseases in higher concentrations (>30 μg/m). This study indicated significant associations of PM with cardiopulmonary outpatient visit. Such results may be used for health risk assessment and policy making for particulate air pollution control.