Occupational Radiation Exposure in US Radiologic Technologists and Absolute Risk of Cataract Incidence Assessed Using a Generalized Additive Model

• Activity Number: 304 - Risk Applications for Disease, Toxicology, and Biomarker Modeling
• Type: Contributed
• Date/Time: Tuesday, July 30, 2019 : 8:30 AM to 10:20 AM
• Sponsor: Section on Risk Analysis
• Author(s): Mark P Little* and Elizabeth K Cahoon and Cari M Kitahara and Steven L Simon and Nobuyuki Hamada and Martha S Linet
• Companies: Radiation Epidemiology Branch, National Cancer Institute and National Cancer Institute and National Cancer Institute and National Cancer Institute and Radiation Safety Research Center, Nuclear Technology Research Laboratory, CRIEPI and National Cancer Institute
• Keywords: cataract; diabetes; generalized additive model; radiation; occupational risk; diagnostic risk

Abstract

Using a generalized additive model we estimated absolute risks of cataract in a cohort of US radiologic technologists in relation to occupational radiation exposure, and assessed modifications of radiogenic risk by a priori selected cataract risk factors (diabetes, body mass index, smoking, race, sex, birth year, UVB exposure). There were 11,345 diagnoses of cataract during 832,462 person years of follow-up. Occupational radiation exposure was strongly associated with self-reported cataract, with an excess absolute risk / 104 person year Gy of 93 (95% CI 46 to 142, p< 0.001). There was significant (p< 0.001) modification of radiogenic risk by age, and by diabetes status (p< 0.001), with risk higher among older persons (age ? 75 years) and those with diabetes. There was significantly elevated absolute risk for occupational radiation eye lens doses under 100 mGy (p=0.006) but not under 50 mGy, and no significant curvature (p=0.893) in the dose response. The notably elevated absolute risks associated with low-dose radiation, if confirmed in other studies, have important public health and clinical implications for radiation workers as well as worker protection and regulatory measures.