Objective: To carry out a quantitative estimate that related to the effects of short-term exposure to PM(2.5) on all-cause mortality and emergency visits in China by using the systematic review and Meta-analysis. Methods: We selected all the studies published before March 2018 from China National Knowledge Infrastructure, Wanfang database, PubMed and EMBASE and data on relative risk (RR), excess risk (ER) and their 95%CIs: appeared in these papers were extracted. According to the differences in the size or direction (heterogeneity) of the results, we computed summary estimates of the effect values using a random-effect or fixed effect model. We also conducted the subgroup analysis and Meta-analysis to have assessed the selected studies for the evidence of study bias. Results: A total of 33 original studies, indexed in databases, were identified. Among those studies, 39 sets of data on mortality and 4 sets of data on emergency were valid to show that within the daily concentration range from 47.7 to 176.7 μg/m(3), for 10 μg/m(3) increases in PM(2.5) concentrations, it would increase the daily numbers of deaths by 0.49% (95%CI: 0.39%-0.59%) and 0.30% (95%CI: 0.10%-0.51%) for all-cause deaths and all-cause emergency-room visits, respectively. For subgroup analysis, the combined effect of PM(2.5) in causing short-term all-cause deaths in the northern areas (ER=0.42%, 95%CI: 0.30%-0.54%) seemed lower than that in the southern areas (ER=0.63%, 95%CI: 0.44%-0.82%). The combined effect of PM(2.5) concentration below 75 μg/m(3) (ER=0.50%, 95%CI: 0.37%-0.62%) was higher than that of PM(2.5) concentration ≥75 μg/m(3) (ER=0.39%, 95%CI: 0.26%-0.52%). Conclusion: Within the concentration range from 47.7 to 176.7 μg/m(3), short-term exposure to current level of PM(2.5) might increase both the all-cause daily mortality and daily emergency visits in China.
目的： 利用Meta分析定量评价空气中粒径≤2.5 μm的颗粒物（PM(2.5)）短期暴露与我国居民全因死亡和急诊之间的关系。 方法： 于2018年3月系统检索中国知网、万方数据知识服务平台、PubMed和EMBASE收集相关文献，提取相对危险度（RR）、超额危险度（ER）及其95%CI，根据异质性检验结果，采用固定或随机效应模型对数据进行合并，并对其进行亚组分析、Meta回归和检验发表偏倚。 结果： 共纳入33篇原始文献，分别利用39组死亡数据和4组急诊量数据进行Meta分析，结果显示，在47.7~176.7 μg/m(3)的浓度范围内，PM(2.5)每上升10 μg/m(3)，居民每日全因死亡增加0.49%（95%CI：0.39%~0.59%），全因急诊量增加0.30%（95%CI：0.10%~0.51%）。对死亡数据的亚组分析显示北方地区（ER=0.42%，95%CI：0.30%~0.54%）合并效应值低于南方地区（ER=0.63%，95%CI：0.44%~0.82%），研究期间PM(2.5)浓度<75 μg/m(3)地区的合并效应值（ER=0.50%，95%CI：0.37%~0.62%）高于PM(2.5)浓度≥75 μg/m(3)的地区（ER=0.39%，95%CI：0.26%~0.52%）。 结论： 在47.7~176.7 μg/m(3)的浓度范围内，PM(2.5)短期暴露可能与全因死亡和急诊量增加有关。.
Keywords: Air pollution; All-cause emergency room visits; All-cause mortality; Short-term effects.