Salvan Alberto, Ranucci Alessandra, Lagorio Susanna, Magnani Corrado
Institute for Systems Analysis and Computer Science "Antonio Ruberti", IASI-CNR, Via dei Taurini 19, 00185 Rome, Italy.
Medical Statistics & Cancer Epidemiology Unit-Department of Translational Medicine, CPO Piemonte and University of Eastern Piedmont, Via Solaroli 17, 28100 Novara, Italy.
Int J Environ Res Public Health. 2015 Feb 16;12(2):2184-204. doi: 10.3390/ijerph120202184.
We report on an Italian case-control study on childhood leukemia and exposure to extremely low frequency magnetic fields (ELF-MF). Eligible for inclusion were 745 leukemia cases, aged 0-10 years at diagnosis in 1998-2001, and 1475 sex- and age-matched population controls. Parents of 683 cases and 1044 controls (92% vs. 71%) were interviewed. ELF-MF measurements (24-48 h), in the child's bedroom of the dwelling inhabited one year before diagnosis, were available for 412 cases and 587 controls included in the main conditional regression analyses. The magnetic field induction was 0.04 μT on average (geometric mean), with 0.6% of cases and 1.6% of controls exposed to >0.3 μT. The impact of changes in the statistical model, exposure metric, and data-set restriction criteria was explored via sensitivity analyses. No exposure-disease association was observed in analyses based on continuous exposure, while analyses based on categorical variables were characterized by incoherent exposure-outcome relationships. In conclusion, our results may be affected by several sources of bias and they are noninformative at exposure levels >0.3 μT. Nonetheless, the study may contribute to future meta- or pooled analyses. Furthermore, exposure levels among population controls are useful to estimate attributable risk.
我们报告了一项关于儿童白血病与极低频磁场（ELF-MF）暴露的意大利病例对照研究。纳入的病例为1998年至2001年诊断时年龄在0至10岁的745例白血病患者，以及1475名性别和年龄匹配的人群对照。对683例病例和1044名对照（92%对71%）的父母进行了访谈。主要条件回归分析纳入的412例病例和587名对照中，有其诊断前一年居住房屋内儿童卧室的ELF-MF测量值（24 - 48小时）。磁场感应平均为0.04μT（几何均值），0.6%的病例和1.6%的对照暴露于>0.3μT。通过敏感性分析探讨了统计模型、暴露指标和数据集限制标准变化的影响。基于连续暴露的分析未观察到暴露与疾病的关联，而基于分类变量的分析则表现出不一致的暴露 - 结局关系。总之，我们的结果可能受到多种偏倚来源的影响，并且在暴露水平>0.3μT时无信息价值。尽管如此，该研究可能有助于未来的荟萃分析或汇总分析。此外，人群对照中的暴露水平有助于估计归因风险。
