目的 运用病例交叉的研究方法探讨大气污染对武汉市居民呼吸系统疾病每日死亡的影响。方法采用病例交叉(case—crossover)设计的方法研究2005年1月1日至2006年12月31日期间武汉市城区大气污染与居民每日呼吸系统疾病的死亡之间的关系,同时比较不同的对照选择方案研究结果的差异。结果调整相关气象因素后,采用双向1:2的对照设计分析表明,大气可吸入颗粒物(PMIO)、二氧化硫(SO:)以及二氧化氮(NO:)日平均浓度每增加10μg/m3,武汉市城区居民呼吸系统疾病死亡发生的OR值分别为1.005(95%CI:1.004~1.006)、1.021(95%CI:1.019~1.023)和1.054(95%CI:1.047—1.054);在不同的对照策略下,PM10、SO2以及NO2与呼吸系统死亡关联均有统计学意义(P〈O.05),且NO2的关联值相对较高。结论本研究区域内大气PMIO、SO2以及NO2浓度的上升促进呼吸系统疾病死亡的增加。
Objective Using case-crossover design to estimate the effect of air pollution on daily mortality of respiratory diseases in Wuhan. Methods Case-crossover technique was used to evaluate the relationship between air pollution and daily mortality from January 2005 to December 2006 in Wuhan. The results of the bidirectional control sampling approach were compared with unidirectional approach. Results As the weather conditions adjusted, the results showed that the odds ratio (OR) value of the daily mortality for the respiratory diseases associated with each 10 μg/m3 increment of PM10, SO2, NO2 were 1.005 (95%CI:1.004-1.006), 1.021 (95%CI:1.019-1.023), 1.054 (95%CI:1.047-1.054) respectively. Significant associations were observed between PM10, S02, NO2 and daily mortality of respiratory diseases by different control sampling approaches (P〈 0.05 ), especially for NO2. Conclusion The elevated level of PM 10, SO2 and NO2 can increase the daily mortality of respiratory diseases in Wuhan city.