Wells Ellen M, Bonfield Tracey L, Dearborn Dorr G, Jackson Leila W
Department of Environmental Health Sciences, Case Western Reserve University School of Medicine, Cleveland, OH, USA; Department of Epidemiology and Biostatistics, Case Western Reserve University School of Medicine, Cleveland, OH, USA.
Department of Pediatrics, Case Western Reserve University School of Medicine, Cleveland, OH, USA.
Int J Hyg Environ Health. 2014 Mar;217(2-3):196-204. doi: 10.1016/j.ijheh.2013.04.010. Epub 2013 May 9.
Early life lead exposure may alter immune function and predispose a child to develop asthma. In an initial exploration of this hypothesis, we examined the association between blood lead, and serum immunoglobulin E (IgE), eosinophils, and asthma prevalence in a cross-sectional study of 1788 children from the National Health and Nutrition Examination Survey 2005-2006. Geometric mean blood lead, serum IgE, and percent eosinophils were 1.13 μg/dL (95% confidence interval (CI): 1.04, 1.22), 46.3 kU/L (95% CI: 40.3, 53.1), and 2.82 percent (95% CI 2.67, 2.98), respectively. Prevalence of asthma, atopic asthma, and atopy were 11.8% (95% CI: 9.5, 14.2), 8.1% (6.2, 9.9), and 44.4% (40.1, 48.7), respectively. Regression models controlled for season, age, sex, race/ethnicity, education, passive smoke exposure, and body mass index. Based on these models, there was an 11.1% (95% CI: 5.6, 16.9) increase in IgE and a 4.9% (95% CI: 2.3, 7.6) increase in eosinophils per 1 μg/dL increase in blood lead. In independent stratified analyses, lead was found to increase IgE and eosinophils among non-Hispanic whites, but not other children; and stronger associations were observed among children who lived with a smoker vs. not. Lead was not associated with asthma, atopic asthma, or general atopy. This study provides additional evidence of a cross-sectional association between lead with IgE and new evidence for eosinophils. This may be a mechanism for development of downstream allergic disease. The mechanisms that determine ultimate development of allergic disease are currently unknown, but are the focus of ongoing studies.
儿童早期铅暴露可能会改变免疫功能，使儿童更容易患哮喘。在对这一假设的初步探索中，我们在一项针对2005 - 2006年美国国家健康与营养检查调查中1788名儿童的横断面研究中，检验了血铅与血清免疫球蛋白E（IgE）、嗜酸性粒细胞以及哮喘患病率之间的关联。血铅、血清IgE的几何均值以及嗜酸性粒细胞百分比分别为1.13μg/dL（95%置信区间（CI）：1.04，1.22）、46.3kU/L（95%CI：40.3，53.1）和2.82%（95%CI：2.67，2.98）。哮喘、特应性哮喘和特应性的患病率分别为11.8%（95%CI：9.5，14.2）、8.1%（6.2，9.9）和44.4%（40.1，48.7）。回归模型对季节、年龄、性别、种族/民族、教育程度、被动吸烟暴露和体重指数进行了控制。基于这些模型，血铅每升高1μg/dL，IgE升高11.1%（95%CI：5.6，16.9），嗜酸性粒细胞升高4.9%（95%CI：2.3，7.6）。在独立分层分析中，发现铅会使非西班牙裔白人的IgE和嗜酸性粒细胞升高，但其他儿童则不然；并且在与吸烟者同住的儿童中观察到的关联更强。铅与哮喘、特应性哮喘或一般特应性无关。这项研究为铅与IgE之间的横断面关联提供了更多证据，并为嗜酸性粒细胞提供了新证据。这可能是下游过敏性疾病发生发展的一种机制。目前尚不清楚决定过敏性疾病最终发展的机制，但这是正在进行的研究的重点。
