BACKGROUND Prenatal exposures to ambient air pollution and traffic have been associated with adverse birth outcomes, and may also lead to an increased risk of obesity. Obesity risk may be reflected in changes in body composition in infancy. OBJECTIVE To estimate associations between prenatal ambient air pollution and traffic exposure, and infant weight and adiposity in a Colorado-based prospective cohort study. METHODS Participants were 1125 mother-infant pairs with term births. Birth weight was recorded from medical records and body composition measures (fat mass, fat-free mass, and adiposity [percent fat mass]) were evaluated via air displacement plethysmography at birth (n = 951) and at ~5 months (n = 574). Maternal residential address was used to calculate distance to nearest roadway, traffic density, and ambient concentrations of fine particulate matter (PM2.5) and ozone (O3) via inverse-distance weighted interpolation of stationary monitoring data, averaged by trimester and throughout pregnancy. Adjusted linear regression models estimated associations between exposures and infant weight and body composition. RESULTS Participants were urban residents and diverse in race/ethnicity and socioeconomic status. Average ambient air pollutant concentrations were generally low; the median, interquartile range (IQR), and range of third trimester concentrations were 7.3 μg/m3 (IQR: 1.3, range: 3.3-12.7) for PM2.5 and 46.3 ppb (IQR: 18.4, range: 21.7-63.2) for 8-h maximum O3. Overall there were few associations between traffic and air pollution exposures and infant outcomes. Third trimester O3 was associated with greater adiposity at follow-up (2.2% per IQR, 95% CI 0.1, 4.3), and with greater rates of change in fat mass (1.8 g/day, 95% CI 0.5, 3.2) and adiposity (2.1%/100 days, 95% CI 0.4, 3.7) from birth to follow-up. CONCLUSIONS We found limited evidence of an association between prenatal traffic and ambient air pollution exposure and infant body composition. Suggestive associations between prenatal ozone exposure and early postnatal changes in body composition merit further investigation.

中文翻译：

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产前交通和环境空气污染以及婴儿体重和肥胖的暴露：“健康开始”研究。

背景技术产前暴露于环境空气污染和交通已经与不良的出生结果相关联，并且还可能导致肥胖的风险增加。肥胖的风险可能反映在婴儿期身体成分的变化上。目的在一项基于科罗拉多州的前瞻性队列研究中，评估产前环境空气污染和交通暴露与婴儿体重和肥胖之间的关联。方法参加研究的是1125对足月出生的母婴。从医疗记录中记录出生体重，并在出生时（n = 951）和〜5个月（n = 574）通过空气体积体积描记法评估身体成分（脂肪质量，无脂肪质量和肥胖[脂肪质量百分比]） ）。孕产妇住所地址用于计算到最近道路的距离，交通密度，静态监测数据的反距离加权插值，计算出妊娠中期和整个怀孕期间的平均细颗粒物（PM2.5）和臭氧（O3）的环境浓度。调整后的线性回归模型估计了暴露与婴儿体重和身体组成之间的关联。结果参与者是城市居民，种族/民族和社会经济地位各不相同。平均周围空气污染物浓度普遍较低；PM2.5的中位数，四分位间距（IQR）和孕中期浓度范围为7.3μg/ m3（IQR：1.3，范围：3.3-12.7）和42.5 ppb（IQR：18.4，范围：21.7-63.2） O3最大值为8小时。总体而言，交通和空气污染暴露与婴儿结局之间几乎没有关联。孕晚期O3与随访时更大的肥胖有关（2。每次IQR为2％，95％CI为0.1、4.3），脂肪质量变化率更高（1.8 g /天，95％CI为0.5、3.2）和肥胖（2.1％/ 100天，95％CI为0.4、3.7） ）从出生到随访。结论我们发现有限的证据表明产前交通与周围空气污染暴露和婴儿身体成分之间存在关联。产前臭氧暴露与产后早期身体成分变化之间的暗示关联值得进一步研究。