Lian Yulong, Xiao Jing, Ji Xiaoli, Guan Suzhen, Ge Hua, Li Fuye, Ning Li, Liu Jiwen
Division of Occupational and Environmental Health, College of Public Health, Nantong University, Nantong, Jiangsu, China Division of Occupational and Environmental Health, College of Public Health, Xinjiang Medical University, Urumqi, Xinjiang, China.
Division of Occupational and Environmental Health, College of Public Health, Nantong University, Nantong, Jiangsu, China.
Occup Environ Med. 2015 Sep;72(9):640-7. doi: 10.1136/oemed-2014-102772. Epub 2015 Jul 10.
The aim of this study was to assess the risk of cataract following protracted low doses of radiation exposure among industry radiographers and comparison groups of unexposed workers.
A cohort of 1401 industry radiographers and 1878 unexposed workers in China was followed up for 12 years. The lens doses were based on individual monitoring. Presence of cataract was assessed clinically based on lens photographs using the Lens Opacities Classification System III. Radiation dose-response analyses were performed for cataract incidence by using Poisson regression, adjusting for confounding factors.
Industry radiographers were significantly more likely than unexposed workers to develop cortical (HR=2.58, 95% CI 1.36 to 3.82), posterior subcapsular (PSC) cataract (HR=3.57, 95% CI 1.27 to 4.79) and mixed cataract (HR=3.25, 95% CI 1.20 to 6.78), but not nuclear cataract (HR=0.93, 95% CI 0.78 to 1.11). Hypertension, diabetes mellitus, old age at exposure, and high body mass index (>27 km/m(2)) were significantly associated with increased risk of cortical, PSC and mixed cataracts. However, the risk decreased for regular users of shielded enclosures, lead eyeglasses and lead aprons. No dose-effect relationship was observed for cortical (excess relative risk (ERR)/Sv=0.16; 95% CI -0.04 to 0.36) and PSC cataract (ERR/Sv=0.14; 95% CI -0.90 to 0.76).
The results indicated a radiation effect for cortical and PSC cataract at doses less than the annual limit of the International Commission on Radiological Protection (ICRP) guidelines. Regarding current eye risk guidelines, the results challenged the ICRP assumption that cataract is a dose-limiting ocular pathology. Regular use of radiation-protective equipment is therefore strongly recommended for eye safety.
本研究旨在评估工业放射技师以及未接触辐射的对照人群在长期低剂量辐射暴露后患白内障的风险。
对中国的1401名工业放射技师和1878名未接触辐射的工人进行了为期12年的随访。晶状体剂量基于个人监测。使用晶状体混浊分类系统III，根据晶状体照片对白内障的存在情况进行临床评估。通过泊松回归对白内障发病率进行辐射剂量反应分析，并对混杂因素进行校正。
与未接触辐射的工人相比，工业放射技师患皮质性白内障（风险比[HR]=2.58，95%置信区间[CI]为1.36至3.82）、后囊下白内障（PSC，HR=3.57，95%CI为1.27至4.79）和混合性白内障（HR=3.25，95%CI为1.20至6.78）的可能性显著更高，但核性白内障的患病风险无显著差异（HR=0.93，95%CI为0.78至1.11）。高血压、糖尿病、暴露时年龄较大以及高体重指数（>27kg/m²）与皮质性、PSC和混合性白内障的患病风险增加显著相关。然而，对于经常使用屏蔽罩、铅眼镜和铅围裙的人，患病风险会降低。未观察到皮质性白内障（超额相对危险度[ERR]/Sv=0.16；95%CI为-0.04至0.36）和PSC白内障（ERR/Sv=0.14；95%CI为-0.90至0.76）的剂量效应关系。
结果表明，在低于国际放射防护委员会（ICRP）指南年度限值的剂量下，皮质性和PSC白内障存在辐射效应。就当前的眼部风险指南而言，该结果对ICRP关于白内障是剂量限制眼部病变的假设提出了挑战。因此，强烈建议为保护眼睛安全经常使用辐射防护设备。
