Department of Epidemiology and Biostatistics, School of Public Health, Wuhan University of Science and Technology, Wuhan, China; Hubei Province Key Laboratory of Occupational Hazard Identification and Control, Wuhan University of Science and Technology, Wuhan, China.
Department of Chemical and Biochemical Engineering, Iowa Technology Institute, The University of Iowa, Iowa City, Iowa.
J Allergy Clin Immunol. 2021 Sep;148(3):771-782.e12. doi: 10.1016/j.jaci.2021.02.030. Epub 2021 Mar 5.
Emerging research suggested an association of early-life particulate air pollution exposure with development of asthma in childhood. However, the potentially differential effects of submicron particulate matter (PM; PM with aerodynamic diameter ≤1 μm [PM]) remain largely unknown.
This study primarily aimed to investigate associations of childhood asthma and wheezing with in utero and first-year exposures to size-specific particles.
We conducted a large cross-sectional survey among 5788 preschool children aged 3 to 5 years in central China. In utero and first-year exposures to ambient PM, PM with aerodynamic diameter less than or equal to 2.5 μm, and PM with aerodynamic diameter less than or equal to 10 μm at 1 × 1-km resolution were assessed using machine learning-based spatiotemporal models. A time-to-event analysis was performed to examine associations between residential PM exposures and childhood onset of asthma and wheezing.
Early-life size-specific PM exposures, particularly during pregnancy, were significantly associated with increased risk of asthma, whereas no evident PM-wheezing associations were observed. Each 10-μg/m increase in in utero and first-year PM exposure was accordingly associated with an asthma's hazard ratio in childhood of 1.618 (95% CI, 1.159-2.258; P = .005) and 1.543 (0.822-2.896; P = .177). Subgroup analyses suggest that short breast-feeding duration may aggravate PM-associated risk of childhood asthma. Each 10-μg/m increase in in utero exposure to PM, for instance, was associated with a hazard ratio of 2.260 (1.393-3.666) among children with 0 to 5 months' breast-feeding and 1.156 (0.721-1.853) among those longer breast-fed.
Our study added comparative evidence for increased risk of childhood asthma in relation to early-life PM exposures, highlighting stronger associations with ambient PM than with PM with aerodynamic diameter less than or equal to 2.5 μm and PM with aerodynamic diameter less than or equal to 10 μm.
新的研究表明，儿童时期早期空气中的颗粒物暴露与哮喘的发展有关。然而，亚微米颗粒物（PM；空气动力学直径≤1μm 的 PM，即 PM）的潜在差异效应在很大程度上尚不清楚。
本研究主要旨在研究儿童哮喘和喘息与宫内和第一年暴露于特定大小颗粒的关联。
我们在中国中部对 5788 名 3 至 5 岁的学龄前儿童进行了一项大型横断面调查。使用基于机器学习的时空模型，以 1×1km 分辨率评估了环境 PM、空气动力学直径小于或等于 2.5μm 的 PM 和空气动力学直径小于或等于 10μm 的 PM 的宫内和第一年暴露情况。进行时间事件分析，以检查住宅 PM 暴露与儿童哮喘和喘息发病之间的关联。
生命早期特定大小的 PM 暴露，特别是在怀孕期间，与哮喘风险增加显著相关，而与 PM 与喘息之间没有明显关联。宫内和第一年 PM 暴露每增加 10μg/m，儿童期哮喘的危险比分别为 1.618（95%CI，1.159-2.258；P=0.005）和 1.543（0.822-2.896；P=0.177）。亚组分析表明，母乳喂养时间较短可能会加重 PM 与儿童哮喘风险之间的关联。例如，宫内暴露于 PM 每增加 10μg/m，母乳喂养时间为 0 至 5 个月的儿童的危险比为 2.260（1.393-3.666），而母乳喂养时间较长的儿童的危险比为 1.156（0.721-1.853）。
我们的研究为与生命早期 PM 暴露有关的儿童哮喘风险增加提供了比较证据，强调了与环境 PM 相比，与空气动力学直径小于或等于 2.5μm 的 PM 和空气动力学直径小于或等于 10μm 的 PM 的关联更强。
