城市儿童中产前空气颗粒物污染与哮喘发生：鉴定敏感窗和性别差异
2015/09/07
摘要
原理：空气颗粒物污染对于呼吸健康的影响始于出生之前。胎儿的肺部生长和结构发育是分阶段进行的，因此，空气颗粒物污染对于出生后呼吸系统疾病的影响可能因暴露时间的不同而有所差异。
目的：我们采用一项新颖的方法，在城市妊娠队列中鉴定产前直径≤2.5μm颗粒物(PM2.5)暴露对于儿童哮喘发展影响的敏感窗。
方法：共纳入736例足月(≥37周) 儿童进行分析。怀孕期间每位母亲的每日PM2.5暴露量通过经验证的基于卫星的时空解决模型进行预估。使用分布滞后模型(DLMs)，我们研究了妊娠期间每周平均PM2.5水平与儿童6岁之前被诊断为哮喘的相关性。对性别影响也进行了研究。
主要结果：大部分母亲为少数民族（54%西班牙裔，30%黑人），接受教育时间≤12年(66%)，妊娠期间不吸烟(80%)。在整个样本中，校正儿童年龄、性别和母亲因素（教育、种族/民族、吸烟、压力、特异反应、产前肥胖）后的DLMs表明：在妊娠16-25周期间增加的PM2.5暴露水平与早期儿童哮喘发生显著相关。性别分层分析表明：PM2.5和性别的相互影响非常显著，且这种相关性只存在于男孩中。
结论：在男孩中，妊娠中期的高PM2.5暴露与6岁之前哮喘发生相关。更好的描述敏感窗的方法可能有利于发现潜在的机制。
（杨冬 审校）
Am J Respir Crit Care Med. 2015 Jul 15. [Epub ahead of print]
Prenatal Particulate Air Pollution and Asthma Onset in Urban Children: Identifying Sensitive Windows and Sex Differences.
Hsu HL1, Chiu YM2, Coull BA3, Kloog I4, Schwartz J5, Lee A6, Wright RO7, Wright RJ8,9.
Abstract
RATIONALE:The influence of particulate air pollution on respiratory health starts in utero. Fetal lung growth and structural development occurs in stages, thus effects on postnatal respiratory disorders may differ based on timing of exposure.
OBJECTIVES:We implemented an innovative method to identify sensitive windows for effects of prenatal exposure to particulate matter with a diameter≤2.5μm (PM2.5) on children's asthma development in an urban pregnancy cohort.
METHODS & MEASURES:Analyses included 736 full-term (≥37 weeks) children. Each mother's daily PM2.5 exposure was estimated over gestation using a validated satellite-based spatio-temporal resolved model. Using distributed lag models (DLMs), we examined associations between weekly averaged PM2.5 levels over pregnancy and physician diagnosed asthma in children by age 6 years. Effect modification by sex was also examined.
MAIN RESULTS:Most mothers were ethnic minorities (54% Hispanic, 30% black), had ≤12 years of education (66%) and did not smoke in pregnancy (80%). In the sample as a whole, DLMs adjusting for child age, sex, and maternal factors (education, race/ethnicity, smoking, stress, atopy, pre-pregnancy obesity) showed that increased PM2.5 exposure levels at 16-25 weeks gestation were significantly associated with early childhood asthma development. An interaction between PM2.5 and sex was significant (p=0.01) with sex-stratified analyses showing that the association exists only for boys.
CONCLUSIONS:Higher prenatal PM2.5 exposure at mid-gestation was associated with asthma development by age 6 years in boys. Methods to better characterize vulnerable windows may provide insight into underlying mechanisms.
Am J Respir Crit Care Med. 2015 Jul 15. [Epub ahead of print]
