Southern Urals Biophysics Institute, Ozyorskoe Shosse 19, Ozyorsk, Chelyabinsk Region, 456780, Russian Federation.
Health Phys. 2012 Jul;103(1):3-14. doi: 10.1097/HP.0b013e3182243a62.
Following an earlier study of incidence and mortality of ischemic heart disease (IHD) published in 2010, a second analysis has been conducted based on an extended cohort and five additional years of follow-up. The cohort includes 18,763 workers, of whom 25% were females, first employed at the Mayak PA in 1948-1972 and followed up to the end of 2005. Some of these workers were exposed to external gamma rays only, and others were exposed to a mixture of external gamma-rays and internal alpha-particle radiation. A total of 6,134 cases and 2,629 deaths from IHD were identified in the study cohort. A statistically significant increasing trend was found with total external gamma-ray dose in IHD incidence (ERR/Gy 0.099; 95% CI: 0.045-0.153) after adjusting for non-radiation factors. This value reduced slightly when adjusting for internal liver dose. There was no statistically significant increase trend for internal liver dose in IHD incidence. These findings were consistent with an earlier study. New findings in IHD incidence revealed a statistically significant decrease in IHD incidence among workers exposed to external gamma-rays doses of 0.2-0.5 Gy in relation to the external doses below 0.2 Gy. This decreased risk is heavily influenced by female workers. This finding has never been reported in other studies, and the results should be treated with caution. The findings for IHD mortality are similar to those results in the earlier analysis; there was no statistically significant trend with external gamma-ray dose or for internal liver dose after adjustment for external dose. The risk estimates obtained from these analyses of IHD incidence and mortality in relation to external gamma-rays in the cohort of Mayak workers are generally compatible with those from other large occupational radiation worker studies and the Japanese atomic bomb survivors.
继 2010 年发表的一项关于缺血性心脏病（IHD）发病率和死亡率的早期研究之后，基于一个扩展队列和五年的额外随访进行了第二次分析。该队列包括 18763 名工人，其中 25%为女性，于 1948-1972 年首次在 MayakPA 就业，并随访至 2005 年底。其中一些工人仅受到外照射γ射线的照射，而另一些则受到外照射γ射线和内照射α粒子辐射的混合照射。在研究队列中，共发现 6134 例 IHD 病例和 2629 例 IHD 死亡。在调整非辐射因素后，发现 IHD 发病率与总外照射γ剂量呈统计学上显著的递增趋势（ERR/Gy 0.099；95%CI：0.045-0.153）。当调整内肝剂量时，该值略有降低。内肝剂量与 IHD 发病率之间没有统计学上显著的递增趋势。这些发现与早期研究一致。IHD 发病率的新发现显示，与外照射剂量低于 0.2Gy 的工人相比，暴露于 0.2-0.5Gy 外照射γ剂量的工人的 IHD 发病率呈统计学显著下降。这种风险降低受女性工人的影响较大。这一发现从未在其他研究中报道过，结果应谨慎对待。IHD 死亡率的结果与早期分析的结果相似；在调整外照射剂量后，外照射γ剂量或内肝剂量与 IHD 死亡率之间没有统计学上显著的趋势。从这些队列研究中获得的关于 Mayak 工人外照射γ射线与 IHD 发病率和死亡率的风险估计值通常与其他大型职业辐射工人研究和日本原子弹幸存者的结果一致。
