Department of Pediatrics, Taipei Hospital, Ministry of Health and Welfare, Taipei, Taiwan.
Institute of Environmental and Occupational Health Sciences, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
J Expo Sci Environ Epidemiol. 2017 Sep;27(5):478-483. doi: 10.1038/jes.2017.5. Epub 2017 Apr 12.
Lead (Pb) has adverse effects on our nervous system and renal systems. Young children are more vulnerable to Pb exposure. However, the role of low-level Pb exposure in the immune system and allergic diseases in children is not well established. The aims of this study are to investigate the associations between Pb exposure and allergic diseases; between Pb and immunoglobulin E (IgE) as an intervening variable; and gender-based differences. We used multistage stratified random sampling to recruit kindergarten children nationwide in Taiwan. Information about allergic diseases and environmental exposures was collected by questionnaire. We compared children with and without allergic diseases for blood Pb levels measured by inductively coupled plasma mass spectrometry. The association between blood Pb and allergic diseases was assessed by logistic regression and those between Pb and IgE by generalized linear models. We also conducted mediation analysis to evaluate how much risk of allergic diseases related to Pb exposure is explained by IgE. A total of 930 children completed specimen collections. There was a positive association between Pb and asthma. Blood Pb were also positively linked with serum IgE (β=0.26 kU/l per ln-unit increase Pb concentration; 95% CI 0.009-0.50 kU/l), after adjusting for potential confounders. Analyses stratified by gender revealed that blood Pb correlated with IgE only in boys (β=0.40 kU/l; 95% CI 0.03-0.76 kU/l). We estimated that 38% of the total effect of Pb exposure on asthma is mediated by IgE levels. In conclusion, Pb exposure is associated with both blood IgE and asthma in boys. Moreover, the effect of Pb exposure on asthma may be mediated by IgE levels.
铅（Pb）对我们的神经系统和肾脏系统有不良影响。幼儿更容易受到 Pb 暴露的影响。然而，低水平 Pb 暴露对儿童免疫系统和过敏性疾病的作用尚未得到充分证实。本研究旨在探讨 Pb 暴露与过敏性疾病之间的关系；Pb 与免疫球蛋白 E（IgE）作为中介变量之间的关系；以及性别差异。我们采用多阶段分层随机抽样的方法，在台湾全国范围内招募幼儿园儿童。通过问卷调查收集有关过敏性疾病和环境暴露的信息。我们比较了有和没有过敏性疾病的儿童的血液 Pb 水平，这些水平是通过电感耦合等离子体质谱法测量的。采用逻辑回归评估血液 Pb 与过敏性疾病之间的关联，采用广义线性模型评估 Pb 与 IgE 之间的关联。我们还进行了中介分析，以评估 IgE 解释与 Pb 暴露相关的过敏性疾病风险的程度。共有 930 名儿童完成了标本采集。Pb 与哮喘呈正相关。在调整了潜在的混杂因素后，血液 Pb 与血清 IgE 呈正相关（β=0.26 kU/l/ln 单位增加 Pb 浓度；95%CI 0.009-0.50 kU/l）。按性别分层分析显示，血液 Pb 仅与男孩的 IgE 相关（β=0.40 kU/l；95%CI 0.03-0.76 kU/l）。我们估计，Pb 暴露对哮喘的总效应有 38%是由 IgE 水平介导的。综上所述，Pb 暴露与男孩的血液 IgE 和哮喘均有关联。此外，Pb 暴露对哮喘的影响可能是由 IgE 水平介导的。
