A study on the short-term impact of fine particulate matter pollution on the incidence of cardiovascular diseases in Beijing, China

Recently, air pollution has been substantially decreased in China, including particulate matter (PM) pollution in Beijing. However, PM pollution still has a great impact on human health, as stated in several epidemiological studies. In this paper, we used a generalized additive model (GAM) to evaluate the associations between PM2.5 and cardiovascular diseases from 2009 to 2012 in the Beijing metropolitan area. In GAM, we controlled the confounding factors, such as day of the week and long-term trends. We used the number of daily hospital emergency room (ER) visits to represent the incidence of the studied diseases. We divided the entire study group by gender (i.e., male and female) and age (i.e., 15-60 yr, 60-75 yr, and >= 75 yr). The results showed strong links were observed between increase in PM2.5 concentration and the number of hospital ER visits for cardiovascular diseases. For each interquartile range (IQR) increase in PM2.5, the relative risks (RRs) of the incidence of ischemic heart disease, arrhythmia, high blood pressure, and cerebrovascular disease were 1.023 (95% CI: 1.007-1.040), 1.019 (95% CI: 0.992-1.047), 1.082 (95% CI: 0.985-1.188), 0.976 (95%CI: 0.957-0.996), and 1.038 (95% CI: 1.005-1.072), respectively. Overall, the short-term impact of PM2.5 on the incidence of cardiovascular diseases was the strongest for the 60-75 yr subgroup. For the two different gender subgroups, the short-term impact of PM2.5 on ischemic heart disease and high blood pressure was relatively stronger for the females than for the males, while the opposite was true for arrhythmia and cerebrovascular disease.