Department of Occupational and Environmental Medicine, Cheongju Medical Center, Cheongju 28547, Korea.
People's Health Institute, Seoul 07004, Korea.
Int J Environ Res Public Health. 2018 Mar 9;15(3):481. doi: 10.3390/ijerph15030481.
: A 20-year follow-up study on cancer incidence among people living near nuclear power plants in South Korea ended in 2011 with a finding of significantly, but inconsistently, elevated thyroid cancer risk for females. Reanalysis of the original study was carried out to examine the dose-response relationship further, and to investigate any evidence of detection bias. : In addition to replicating the original Cox proportional hazards models, nested case-control analysis was carried out for all subjects and for four different birth cohorts to examine the effects of excluding participants with pre-existing cancer history at enrollment. The potential for detection bias was investigated using the records of medical utilization and voluntary health checks of comparison groups. : The overall risk profile of the total sample was similar to that of the original study. However, in the stratified analysis of four birth cohorts, the cancer risk among people living near nuclear power plants became higher in younger birth cohorts. This was especially true for thyroid cancers of females (hazard ratio (HR) 3.38) and males (HR 1.74), female breast cancers (HR 2.24), and radiation-related cancers (HR 1.59 for males, HR 1.77 for females), but not for radiation-insensitive cancers (HR 0.59 for males, HR 0.98 for females). Based on medical records and health check reports, we found no differences between comparison groups that could have led to detection bias. : The overall results suggest elevated risk of radiation-related cancers among residents living near nuclear power plants, controlling for the selective survival effect. This is further supported by the lack of evidence of detection bias and by records of environmental exposure from radiation waste discharge.
韩国一项针对核电站附近居民癌症发病率的 20 年随访研究于 2011 年结束，结果显示女性甲状腺癌风险显著升高，但结果不一致。对原始研究进行了重新分析，以进一步研究剂量-反应关系，并调查是否存在检测偏倚的证据。
除了复制原始的 Cox 比例风险模型外，还对所有受试者和四个不同的出生队列进行了嵌套病例对照分析，以检查排除入组时已有癌症病史的参与者对结果的影响。使用对照组的医疗利用记录和自愿健康检查记录来调查检测偏倚的可能性。
总样本的总体风险概况与原始研究相似。然而，在对四个出生队列的分层分析中，核电站附近居民的癌症风险在较年轻的出生队列中更高。这在女性（甲状腺癌 HR 3.38）和男性（HR 1.74）、女性乳腺癌（HR 2.24）和辐射相关癌症（男性 HR 1.59，女性 HR 1.77）中尤其如此，但在辐射不敏感癌症（男性 HR 0.59，女性 HR 0.98）中则不然。根据医疗记录和健康检查报告，我们发现对照组之间没有差异，这些差异可能导致了检测偏倚。
总体结果表明，控制选择性生存效应后，核电站附近居民辐射相关癌症的风险增加。这进一步得到了缺乏检测偏倚证据以及辐射废物排放环境暴露记录的支持。
