Assessing short-term impacts of PM_(2.5) constituents on cardiorespiratory hospitalizations: Multi-city evidence from China

摘要

Apart from concentrations of particulate mass, PM2.5-associated effects on health may largely depend on its chemical components. However, little is known regarding the underlying effects of specific PM2.5 constituents. The study included nearly 1 million hospital admissions from five Chinese cities during 2015–2017. Based on the modified Community Multiscale Air Quality model, our study simulated daily concentrations of PM2.5 and five main components. We used a time-stratified case-crossover design with conditional logistic regression models to estimate short-term effects of PM2.5 constituents on cause-specific hospital admissions. Per interquartile range increase in exposure to PM2.5, elemental carbon, organic carbon, nitrate, sulfate and ammonium at lag 04-day was related to an excess risk (ER%) for non-accidental admissions of 1.6% [95% confidence interval: 1.1–2.0], 1.9% [1.3–2.4], 1.0% [0.5–1.6], 1.2% [0.4–2.0], 1.2% [0.9–1.5] and 1.4% [0.9–1.9], respectively. Great heterogeneities of constituents-admission associations existed in diverse causes and constituents. This study provided multi-center high-quality evidence that hospital admissions, particularly those for ischemic heart disease (ER% ranging from 2.3 to 5.4% at lag 04-day) and pneumonia (1.9–5.1% at lag 4-day), could be triggered by short-term exposures to ambient PM2.5 constituents. Relatively stronger constituents-admission associations were found among females for respiratory causes and the elderly for cardiovascular causes.