[Association between ambient PM10/PM2.5 levels and population mortality of circulatory diseases: a case-crossover...

To explore the association between levels of ambient particulate matters (PM10 and PM2.5) and population mortality of circulatory diseases (ICD10: I00~I99) in Beijing.

The daily data of ambient PM2.5 levels were monitored by the research team in Peking University from Jan. 1, 2007 to Dec. 31, 2008, and the corresponding meteorological and other air quality data (PM10, SO2 and NO2) were collected from National Meteorological Information Center (NMIC) of China and Beijing Environmental Monitoring Center. The data of daily death for the circulatory diseases were collected from the local center for Disease Control and Prevention of Haidian District in Beijing. The symmetric bidirectional case-crossover design and conditional logistic regression model were used for the data analysis. The cases were stratified by gender, age and seasons. The lagged effect was analyzed and the related confounders from meteorological factors and other air pollutants were adjusted.

For a 10 μg/m(3) increase of the ambient concentration of PM2.5, the corresponding increase of daily mortality of the circulatory diseases, cardiovascular diseases and cerebrovascular diseases was 0.78% (95% CI: 0.07% to 1.49%), 0.85% (95% CI: -0.28% to 1.99%), and 0.75% (95% CI: -0.17% to 1.68%), respectively, for a 10 μg/m(3) increase of the ambient concentration of PM10, the corresponding increase of daily mortality of the circulatory diseases, cardiovascular diseases and cerebrovascular diseases was 0.36% (95% CI: -0.07% to 0.78%), 0.63% (95% CI: -0.02% to 1.28%), and 0.33% (95% CI: -0.26% to 0.92%),respectively. The significant positive associations were observed statistically between PM2.5 and the circulatory diseases (P<0.05). The association between ambient PMs and the population mortality was stronger in "warm season (April to September)" than in "cool season (October to the next March)" in Beijing (P<0.05).

The elevated levels of ambient PM2.5 and PM10 were positively associated with the increase of the population mortality of the circulatory diseases, and the association is stronger in warm season, and the adverse effect of PM2.5 is greater than that of PM10.