Spatiotemporal analysis of particulate air pollution and ischemic heart disease mortality in Beijing, China

BACKGROUND: Few studies have used spatially resolved ambient particulate matter with an aerodynamic diameter of <10 μm (PM(10)) to examine the impact of PM(10) on ischemic heart disease (IHD) mortality in China. The aim of our study is to evaluate the short-term effects of PM(10) concentrations on IHD mortality by means of spatiotemporal analysis approach. METHODS: We collected daily data on air pollution, weather conditions and IHD mortality in Beijing, China during 2008 and 2009. Ordinary kriging (OK) was used to interpolate daily PM(10) concentrations at the centroid of 287 township-level areas based on 27 monitoring sites covering the whole city. A generalized additive mixed model was used to estimate quantitatively the impact of spatially resolved PM(10) on the IHD mortality. The co-effects of the seasons, gender and age were studied in a stratified analysis. Generalized additive model was used to evaluate the effects of averaged PM(10) concentration as well. RESULTS: The averaged spatially resolved PM(10) concentration at 287 township-level areas was 120.3 ± 78.1 μg/m(3). Ambient PM(10) concentration was associated with IHD mortality in spatiotemporal analysis and the strongest effects were identified for the 2-day average. A 10 μg/m(3) increase in PM(10) was associated with an increase of 0.33% (95% confidence intervals: 0.13%, 0.52%) in daily IHD mortality. The effect estimates using spatially resolved PM(10) were larger than that using averaged PM(10). The seasonal stratification analysis showed that PM(10) had the statistically stronger effects on IHD mortality in summer than that in the other seasons. Males and older people demonstrated the larger response to PM(10) exposure. CONCLUSIONS: Our results suggest that short-term exposure to particulate air pollution is associated with increased IHD mortality. Spatial variation should be considered for assessing the impacts of particulate air pollution on mortality. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/1476-069X-13-109) contains supplementary material, which is available to authorized users.