大气污染物与呼吸系统疾病急诊就诊关系的病例交叉研究

Association between ambient air pollution and hospital emergency room visits for respiratory diseases： a case-crossover study

目的 分析大气污染急性暴露对呼吸系统疾病急诊人次的影响.方法 收集2004年1月1日至2005年12月31日北京大学第三医院急诊科呼吸系统疾病急诊资料和北京市环境监测中心大气污染物数据,应用时间分层的病例交叉设计研究方法进行数据分析,同时比较单向回顾性对照设计和双向对照设计研究结果的差异.结果 在调整气象因素并采用单向回顾性（多污染物）模型中,无滞后大气可吸入颗粒物（PM10）、二氧化硫（SO2）、滞后2 d二氧化氮（NO2）日平均浓度每增加10 μg/m^3,呼吸系统疾病总急诊的OR值（95%CI）分别为1.010（1.005～1.014）、1.010（1.001～1.018）、0.996（0.983～1.009）;双向对称性（多污染物）模型中,其相应OR值（95%CI）分别为1.002（0.998～1.005）、1.011（1.003～1.018）、1.012（1.001～1.022）.采用不同对照选择方案,病例交叉设计的研究结果有变化.结论 区域内大气污染物暴露对居民呼吸系统疾病急诊人次有急性效应.

Objective Using case-crossover design to explore the association between ambient air pollution and the hospital emergency room visits for respiratory diseases （International Classification of Diseases, tenth vision ICD-10： J00-J99） in Beijing, China. Methods Data regarding the daily hospital emergency room visits＇ of the respiratory diseases （ICD-10： J00-J99）were obtained in 2004.01.01-2005.12.31, from the Peking University Third Hospital and data on relevant air pollution and meteorological factors from the local municipal environmental monitoring center and meteorology bureau of Beijing, respectively. Time-stratified case-crossover technique was used to evaluate their relationships. Results from the bi-directional control sampling approach were compared with unidirectional approach. Results Using a unidirectional control sampling approach,the results obtained from a conditional logistic regression model （multi-pollutant model） after adjusting for meteorological variables, showed that the ORs of the hospital emergency room visits for the respiratory diseases associated with each 10 μg/m^3 increment of PM10, SO2, NO2 were 1.010（95%CI： 1.005-1.014）, 1.010（95%CI： 1.001-1.018） ,0.996（95%CI：0.983-1.009） respectively.In the bi-directional control sampling approach, the ORs were 1.002（95%CI：0.998-1.005）、 1.011 （95%CI：1.003-1.018）、 1.012（95%CI： 1.001-1.022）. Conclusion Results from this study provided evidence that higher levels of ambient air pollutants increased the risk of hospital emergency room visits for respiratory diseases.