Takahashi Hideto, Yasumura Seiji, Takahashi Kunihiko, Ohira Tetsuya, Ohtsuru Akira, Midorikawa Sanae, Suzuki Satoru, Shimura Hiroki, Ishikawa Tetsuo, Sakai Akira, Suzuki Shinichi, Yokoya Susumu, Tanigawa Koichi, Ohto Hitoshi, Kamiya Kenji
National Institute of Public Health, Saitama.
Radiation Medical Science Center for the Fukushima Health Management Survey, Fukushima Medical University.
Medicine (Baltimore). 2020 Jul 2;99(27):e20440. doi: 10.1097/MD.0000000000020440.
Since Fukushima nuclear accident in 2011, thyroid ultrasound examinations have been conducted. The first full-scale examination detected 71 thyroid-cancer cases. This study examined whether radiation exposure was associated with thyroid-cancer incidence.Subjects were participants in the baseline screening and newborns during the 2011 fiscal year. Under nested matched case-control study design, 10 controls per each case were selected by matching the age, sex, baseline screening results, and interval between examinations. With 3 dose levels of external radiation: 1.3 + mSv (upper), 0.8 to 1.3 (middle), and 0.0 to 0.8 (reference), we applied 2 logistic models adjusting for 3 participation-proportions (primary, secondary, and fine-needle aspiratory cytology), overweight, and the B-result of baseline screening (Model 1), and past medical history, family history of thyroid cancer, and frequencies of eating seafood and seaweed in addition to the parameters in Model 1 (Model 2). We examined each model in 3 ways: (a) excluding subjects with a missing radiation exposure dose; and substituting (b1) median or (b2) mean dose of the municipality with missing dose.Odds ratios (ORs) of middle-dose exposure were (a) 1.35 (0.46-3.94), (b1) 1.55 (0.61-3.96), and (b2) 1.23 (0.50-3.03) for Model 1, and (a) 1.18 (0.39-3.57), (b1) 1.31 (0.49-3.49), and (b2) 1.02 (0.40-2.59) for Model 2. For upper-dose exposure, similar results were obtained. Past medical history was significantly associated (odds ratio = 2.04-2.08) with both (b1) and (b2) in Model 2.No significant associations were obtained between the external radiation exposure and thyroid-cancer incidence.
自2011年福岛核事故以来，已开展了甲状腺超声检查。首次全面检查发现了71例甲状腺癌病例。本研究调查了辐射暴露与甲状腺癌发病率之间是否存在关联。研究对象为基线筛查参与者和2011财年的新生儿。在巢式匹配病例对照研究设计下，通过匹配年龄、性别、基线筛查结果以及检查间隔，为每个病例选择10名对照。对于3个外部辐射剂量水平：1.3 + mSv（高剂量）、0.8至1.3（中剂量）以及0.0至0.8（参考剂量），我们应用了2个逻辑模型，对3种参与比例（初次、二次和细针抽吸细胞学检查）、超重以及基线筛查的B结果进行了调整（模型1），并在模型1的参数基础上，对既往病史、甲状腺癌家族史以及食用海鲜和海藻的频率进行了调整（模型2）。我们以3种方式对每个模型进行了检验：(a)排除辐射暴露剂量缺失的受试者；并用(b1)中位数或(b2)均值替代剂量缺失城市的剂量。模型1中，中剂量暴露的比值比（OR）分别为：(a) 1.35（0.46 - 3.94）、(b1) 1.55（0.61 - 3.96）和(b2) 1.23（0.50 - 3.03）；模型2中，中剂量暴露的比值比分别为：(a) 1.18（0.39 - 3.57）、(b1) 1.31（0.49 - 3.49）和(b2) 1.02（0.40 - 2.59）。对于高剂量暴露，也得到了类似结果。在模型2中，既往病史与(b1)和(b2)均显著相关（比值比 = 2.04 - 2.08）。未发现外部辐射暴露与甲状腺癌发病率之间存在显著关联。
