Acute Effects of Particulate Air Pollution on Ischemic Heart Disease Hospitalizations in Shanghai, China

Background: Air pollution has been demonstrated to be a major risk factor for the development of cardiovascular and respiratory diseases worldwide. This study examines the relationship between the exposure to fine particulate matter (PM) and patient hospitalizations as a result of ischemic heart disease (IHD) during 2013–2014 in Shanghai, China. Methods: Daily IHD hospitalization data were acquired from the Shanghai Health Insurance Bureau (SHIB) from 1 January 2013 to 21 December 2014. Daily average concentrations of air pollution as well as meteorological data were obtained from the database of Shanghai Environmental Monitoring Center (SEMC) during the same time period, and all data were analyzed using standard epidemiological methodology. Generalized linear model (GLM) adjusted for time trends, weather conditions, and medical insurance policy was used to estimate the immediate and delayed effects of PMs on IHD hospitalizations, and the effects of PMs were also examined based on gender, age group and seasonal variation. Results: A total of 188,198 IHD hospitalizations were recorded during 2013–2014 in Shanghai, China. During this period, the average concentrations of the fine particulate matter with aerodynamic diameter of <10 μm (PM(10)) and ≤2.5 (PM(2.5)) were 76 µg/m(3) and 56.3 µg/m(3), respectively. The effect of PMs was strongest on days when a 10 μg/m(3) increment increase of PM(2.5) and PM(10), which coincided with an increase in IHD hospitalizations by 0.25% (95% CI: 0.10%, 0.39%) and 0.57% (95% CI: 0.46%, 0.68%), respectively. Furthermore, the effect of PMs was significantly greater in males and people between 41 and 65 years old. Conclusions: Hospitalizations of IHD was strongly associated with short-term exposure to high levels of PM(10) and PM(2.5) during 2013–2014 in Shanghai, China.