Thurston G D, Lippmann M, Scott M B, Fine J M
Nelson Institute of Environmental Medicine, New York University School of Medicine, Tuxedo 10987, USA.
Am J Respir Crit Care Med. 1997 Feb;155(2):654-60. doi: 10.1164/ajrccm.155.2.9032209.
In order to investigate associations between summertime haze air pollution and asthma at an individual level, 52, 58, and 56 children (ages 7 to 13) attending a summer "asthma camp" were followed during the last week of June in 1991, 1992, and 1993, respectively. Most of the subjects had moderate to severe asthma. Daily records were kept of the environmental conditions, as well as of subject medication use, lung function, and medical symptoms. Air pollution was found to be significantly and consistently correlated with acute asthma exacerbations, chest symptoms, and lung function decrements. The pollutant most consistently associated with adverse health consequences was ozone (O3), although associations with sulfates and hydrogen ion suggest a possible role by fine particles as well. Effects were found to be roughly monotonic as a function of O3 concentration. Regression of morning (8:00 A.M.) to afternoon (5:00 P.M.) peak flow change on O3 indicated pulmonary function reductions similar to those previously reported for more active children without asthma. Moreover, analyses also indicated an increased risk of an asthma exacerbation and of experiencing chest symptoms of approximately 40% on the highest pollution day, relative to the mean. Based on these relative risk estimates, a rise in the 1-h daily maximal O3 from 84 ppb to 160 ppb was associated in this group with an increase from 20 to 28 (+/- 2) in the expected number of unscheduled medications administered/day, and from 29 to 41 (+/- 3) in the expected total number of chest symptoms/day. Thus, air pollution can be a major contributor to the respiratory problems experienced by children with asthma during the summer months.
为了在个体层面研究夏季雾霾空气污染与哮喘之间的关联，分别于1991年、1992年和1993年6月的最后一周，对参加夏季“哮喘营”的52名、58名和56名儿童（7至13岁）进行了跟踪调查。大多数受试者患有中度至重度哮喘。每天记录环境状况以及受试者的药物使用情况、肺功能和医学症状。结果发现，空气污染与急性哮喘发作、胸部症状和肺功能下降显著且持续相关。与不良健康后果最密切相关的污染物是臭氧（O3），不过与硫酸盐和氢离子的关联也表明细颗粒物可能也起到了作用。发现影响大致呈O3浓度的单调函数关系。早晨（上午8:00）至下午（下午5:00）峰值流量变化对O3的回归表明，肺功能下降情况与先前报道的没有哮喘的更活跃儿童相似。此外，分析还表明，与平均水平相比，在污染最严重的日子里，哮喘发作和出现胸部症状的风险增加了约40%。基于这些相对风险估计，该组中每日1小时最大O3浓度从84 ppb升至160 ppb，与每日非计划用药预期数量从20次增加到28次（±2次）以及每日胸部症状预期总数从29次增加到41次（±3次）相关。因此，空气污染可能是夏季哮喘儿童呼吸问题的主要促成因素。
