The impact of fine particulate matter on chronic obstructive pulmonary disease deaths in Pudong New Area, Shanghai, during a long period of air quality improvement

Chronic obstructive pulmonary disease (COPD) deaths attributed to fine particulate matter (with an aerodynamic equivalent diameter <2.5 mu m, PM2.5) exposure are a common global public health concern. Recent improvements in air quality and the corresponding health benefits have received much attention. Thus, we have explored the trends of PM2.5 pollution improvement on COPD deaths during an important period of air pollution control (2008-2017) in Pudong New Area, Shanghai, China. Data, including daily COPD death counts, meteorological variables, and ambient air pollutants, were collected from 2008 to 2017. Generalized additive models were fitted to evaluate the percent change (%) in pollution-related COPD deaths. The results showed that the number of days with daily PM2.5 concentrations <35 mu g/m(3) increased from 19 days (5.19%) in 2008 to 166 days (45.48%) in 2017, and PM(2.5 )concentrations >75 mu g/m(3) decreased from 222 days (60.66%) in 2008 to 33 days (9.04%) in 2017. The associations in the overall period between 2008 and 2017 was significant. In subperiod analysis, each 10 mu g/m(3) increment in PM2.5 was associated with a percent change (%) of 0.89 (95% confidence interval [CI], 0.37, 1.42) at lag 5 and 0.78 (95% CI, 0.26, 1.30) at lag 6 during 2008-2013. Significant results were also found at lag 0-5 [percent change (%), 1.12 (95% CI, 0.09, 2.17)], lag 0-6 [percent change (%), 1.52 (95% CI, 0.43, 2.62)] and lag 0-7 [percent change (%), 1.72 (95% CI, 0.57, 2.88)] during 2008-2013. By contrast, no significant association was found between 2014 and 2017. In conclusion, the decreased COPD deaths associated with PM2.5 exposure were found, especially after the air quality improvement turning point in 2014.