Mortimer K M, Tager I B, Dockery D W, Neas L M, Redline S
Department of Epidemiology and Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA.
Am J Respir Crit Care Med. 2000 Nov;162(5):1838-45. doi: 10.1164/ajrccm.162.5.9908113.
Within a cohort of 846 inner-city asthmatic children aged 4 to 9 yr, we looked for subgroups that were more susceptible to the effects of summer ozone. Daily diaries were compared with ambient ozone levels to evaluate effect modification by demographic and environmental characteristics. Children born > 3 wk prematurely or weighing < 5.5 lb. had greater declines in morning % peak expiratory flow rate (PEFR) (1.8% versus 0.3% per 15 ppb ozone, p < 0.05) and a higher incidence of morning symptoms (odds ratio = 1.42 versus 1.09 per 15 ppb ozone, p < 0.05) than did children who had been full-term infants of normal birthweight. Among children who had been of low birthweight (LBW) or had been premature infants, greater declines were seen among those whose reported baseline medication category was "no medication" (3.2% decline) or "steroids" (2.7%) as opposed to beta agonists or xanthines (0.8%) or cromolyn without steroids (0. 1%). Among the children who had been normal birthweight and full-term infants, the cromolyn without steroids group had the greatest declines in %PEFR (1.3%, versus < 0.5% in each of the other three groups). Nonatopic children also had greater responses to ozone. We conclude that among an asthmatic cohort, children who had had an LBW or a premature birth showed the greatest responses to ozone.
在846名年龄在4至9岁的市中心哮喘儿童队列中，我们寻找了对夏季臭氧影响更敏感的亚组。将每日日记与环境臭氧水平进行比较，以评估人口统计学和环境特征对效应的修正作用。早产超过3周或出生体重低于5.5磅的儿童，其早晨呼气峰值流速百分比（PEFR）的下降幅度更大（每15 ppb臭氧下降1.8%，而正常出生体重的足月婴儿为0.3%，p < 0.05），早晨症状的发生率也更高（每15 ppb臭氧的优势比为1.42，而正常出生体重的足月婴儿为1.09，p < 0.05）。在低出生体重（LBW）或早产的儿童中，报告基线用药类别为“不用药”（下降3.2%）或“类固醇”（2.7%）的儿童，其下降幅度大于使用β受体激动剂或黄嘌呤类药物（0.8%）或不含类固醇的色甘酸钠（0.1%）的儿童。在正常出生体重的足月婴儿中，不含类固醇的色甘酸钠组的PEFR百分比下降幅度最大（1.3%，而其他三组均< 0.5%）。非特应性儿童对臭氧的反应也更大。我们得出结论，在哮喘队列中，低出生体重或早产的儿童对臭氧的反应最大。
