School of Population Health, University of Western Australia, Perth, WA, Australia.
Med J Aust. 2010 Nov 1;193(9):511-4. doi: 10.5694/j.1326-5377.2010.tb04034.x.
To determine whether changes in 24-hour average background ozone (O₃), nitrogen dioxide (NO₂), carbon monoxide (CO) and particulates < 10 μm (PM₁₀) increase the risk of hospital emergency department (ED) presentations for asthma among children.
DESIGN, SETTING AND SUBJECTS: A time-stratified case-crossover method was used to analyse data of 603 children and young adults aged 0-19 years who were resident in a south-west metropolitan area of Perth, Western Australia, and who had presented with asthma at any public ED within Perth between 1 January 2002 and 31 December 2006. Effect sizes were assessed in relation to age group, sex and season of exposure. City-wide background air pollution was estimated from air monitoring network data.
ED presentation with asthma.
Patients 0-4 years with 1-day lagged exposure to NO₂ and CO showed the most significant risk of ED presentation for asthma. An interquartile range (IQR) increase in NO₂ resulted in an odds ratio (OR) of 1.70 (95% CI, 1.08-2.69). An IQR increase in CO resulted in an OR of 1.40 (95% CI, 1.06-1.84).
The effect sizes observed in this study were higher than those of past studies, and indicated that children aged 0-4 years were the most vulnerable to the effects of air pollution. The period of exposure most clinically relevant is the day before ED presentation.
确定 24 小时平均背景臭氧（O₃）、二氧化氮（NO₂）、一氧化碳（CO）和小于 10μm 的颗粒物（PM₁₀）的变化是否会增加儿童因哮喘到医院急诊部（ED）就诊的风险。
设计、设置和研究对象：采用时间分层病例交叉法，分析了 2002 年 1 月 1 日至 2006 年 12 月 31 日期间，居住在澳大利亚西澳大利亚州珀斯市西南部，0-19 岁的儿童和年轻人中，在珀斯任何公共 ED 因哮喘就诊的 603 名儿童和年轻人的数据。按年龄组、性别和暴露季节评估了效应大小。从空气质量监测网络数据估算了城市范围的背景空气污染。
ED 就诊的哮喘发作。
0-4 岁的患者在有 1 天滞后的 NO₂和 CO 暴露的情况下，哮喘就诊的风险最大。NO₂的一个四分位间距（IQR）增加导致比值比（OR）为 1.70（95%可信区间，1.08-2.69）。CO 的 IQR 增加导致 OR 为 1.40（95%可信区间，1.06-1.84）。
本研究观察到的效应大小高于过去的研究，表明 0-4 岁的儿童最容易受到空气污染的影响。与临床最相关的暴露期是 ED 就诊前一天。
