Institute of Medical Biostatistics, Epidemiology and Informatics (IMBEI), University Medical Center of the Johannes Gutenberg-University, Mainz, Germany.
Research Center for Bioelectromagnetic Interaction (femu), Institute of Occupational, Social and Environmental Medicine, Medical Faculty, University Hospital RWTH, Aachen, Germany.
Bioelectromagnetics. 2021 May;42(4):271-283. doi: 10.1002/bem.22335. Epub 2021 Mar 25.
Previous meta-analyses have suggested an increased risk of amyotrophic lateral sclerosis (ALS) associated with occupational exposure to extremely low-frequency magnetic fields (ELF-MF). However, results should be interpreted with caution since studies were methodologically heterogeneous. Here, we assessed the feasibility of a pooling study to harmonize and re-analyze available original data. A systematic literature search was conducted. Published epidemiological studies were identified in PubMed and EMF-Portal from literature databases' inception dates until January 2019. The characteristics of all studies were described, including exposure metrics, exposure categories, and confounders. A survey among the principal investigators (PI) was carried out to assess their willingness to provide their original data. The statistical power of a pooling study was evaluated. We identified 15 articles published between 1997 and 2019. Studies differed in terms of outcome, study population, exposure assessment, and exposure metrics. Most studies assessed ELF-MF as average magnetic flux density per working day; however, exposure categories varied widely. The pattern of adjustment for confounders was heterogeneous between studies, with age, sex, and socioeconomic status being most frequent. Eight PI expressed their willingness to provide original data. A relative risk of ≥1.14 for ALS and occupational exposure to ELF-MF can be detected with a power of more than 80% in a pooled study. The pooling of original data is recommended and could contribute to a better understanding of ELF-MF in the etiology of ALS based on a large database and reduced heterogeneity due to a standardized analysis protocol with harmonized exposure metrics and exposure categories. Bioelectromagnetics. © 2021 Bioelectromagnetics Society.
先前的荟萃分析表明，职业接触极低频磁场（ELF-MF）与肌萎缩侧索硬化症（ALS）的风险增加有关。然而，由于研究方法学上存在异质性，结果应谨慎解释。在这里，我们评估了进行汇总研究以协调和重新分析现有原始数据的可行性。进行了系统的文献检索。从文献数据库的开始日期到 2019 年 1 月，在 PubMed 和 EMF-Portal 中识别出已发表的流行病学研究。描述了所有研究的特征，包括暴露指标、暴露类别和混杂因素。对主要研究者（PI）进行了调查，以评估他们提供原始数据的意愿。评估了汇总研究的统计效力。我们确定了 1997 年至 2019 年期间发表的 15 篇文章。这些研究在结果、研究人群、暴露评估和暴露指标方面存在差异。大多数研究评估了 ELF-MF 作为每个工作日的平均磁场通量密度；然而，暴露类别差异很大。研究之间调整混杂因素的模式存在异质性，最常见的是年龄、性别和社会经济地位。有 8 位 PI 表示愿意提供原始数据。在汇总研究中，ALS 职业接触 ELF-MF 的相对风险大于等于 1.14，可以检测到 80%以上的效力。建议汇总原始数据，并且可以根据大型数据库和由于标准化分析协议以及协调的暴露指标和暴露类别而降低的异质性，为更好地了解 ELF-MF 在 ALS 病因学中的作用做出贡献。生物电磁学。2021 年生物电磁学学会。
