Padula Amy M, Mortimer Kathleen, Hubbard Alan, Lurmann Frederick, Jerrett Michael, Tager Ira B
Department of Epidemiology, School of Public Health, University of California, Berkeley, USA.
Am J Epidemiol. 2012 Nov 1;176(9):815-24. doi: 10.1093/aje/kws148. Epub 2012 Oct 7.
Traffic-related air pollution is recognized as an important contributor to health problems. Epidemiologic analyses suggest that prenatal exposure to traffic-related air pollutants may be associated with adverse birth outcomes; however, there is insufficient evidence to conclude that the relation is causal. The Study of Air Pollution, Genetics and Early Life Events comprises all births to women living in 4 counties in California's San Joaquin Valley during the years 2000-2006. The probability of low birth weight among full-term infants in the population was estimated using machine learning and targeted maximum likelihood estimation for each quartile of traffic exposure during pregnancy. If everyone lived near high-volume freeways (approximated as the fourth quartile of traffic density), the estimated probability of term low birth weight would be 2.27% (95% confidence interval: 2.16, 2.38) as compared with 2.02% (95% confidence interval: 1.90, 2.12) if everyone lived near smaller local roads (first quartile of traffic density). Assessment of potentially causal associations, in the absence of arbitrary model assumptions applied to the data, should result in relatively unbiased estimates. The current results support findings from previous studies that prenatal exposure to traffic-related air pollution may adversely affect birth weight among full-term infants.
交通相关空气污染被认为是导致健康问题的一个重要因素。流行病学分析表明，产前暴露于交通相关空气污染物可能与不良出生结局有关；然而，尚无足够证据得出这种关系是因果关系的结论。空气污染、遗传学与早期生活事件研究涵盖了2000年至2006年期间居住在加利福尼亚州圣华金河谷4个县的妇女所生的所有婴儿。利用机器学习和目标最大似然估计法，对孕期交通暴露各四分位数的足月婴儿低出生体重概率进行了估计。如果每个人都居住在交通流量大的高速公路附近（近似为交通密度的第四个四分位数），那么足月低出生体重的估计概率为2.27%（95%置信区间：2.16，2.38），而如果每个人都居住在较小的地方道路附近（交通密度的第一个四分位数），这一概率为2.02%（95%置信区间：1.90，2.12）。在不对数据应用任意模型假设的情况下评估潜在的因果关联，应该会得出相对无偏的估计。目前的结果支持了先前研究的发现，即产前暴露于交通相关空气污染可能会对足月婴儿的出生体重产生不利影响。
