With the exponential increase in minimally invasive fluoroscopically guided interventional radiologic procedures, concern has increased about the health effects on staff and patients of radiation exposure from these procedures. There has been no systematic epidemiologic investigation to quantify serious disease risks or mortality. To quantify all-cause, circulatory system disease and cancer mortality risks in U.S. radiologic technologists who work with interventional radiographic procedures, we evaluated mortality risks in a nationwide cohort of 88,766 U.S. radiologic technologists (77% female) who completed a self-administered questionnaire during 1994-1998 and were followed through 31 December 2003. We obtained information on work experience, types of procedures (including fluoroscopically guided interventional procedures), and protective measures plus medical, family cancer history, lifestyle, and reproductive information. Cox proportional hazards regression models were used to compute relative risks (RRs) with 95% confidence intervals (CIs). Between completion of the questionnaire and the end of follow-up, there were 3,581 deaths, including 1,209 from malignancies and 979 from circulatory system diseases. Compared to radiologic technologists who never or rarely performed or assisted with fluoroscopically guided interventional procedures, all-cause mortality risks were not increased among those working on such procedures daily. Similarly, there was no increased risk of mortality resulting from all circulatory system diseases combined, all cancers combined, or female breast cancer among technologists who daily performed or assisted with fluoroscopically guided interventional procedures. Based on small numbers of deaths (n=151), there were non-significant excesses (40%-70%) in mortality from cerebrovascular disease among technologists ever working with these procedures. The absence of significantly elevated mortality risks in radiologic technologists reporting the highest frequency of interventional radiography procedures must be interpreted cautiously in light of the small number of deaths during the relatively short follow-up. The present study cannot rule out increased risks of cerebrovascular disease, specific cancers, and diseases with low case-fatality rates or a long latency period preceding death.
Bibliographical noteFunding Information:
This research was supported in part by contracts NO1-CP-15673, NO1-CP-51016, and NO2-CP-81121 with the National Cancer Institute, National Institutes of Health, U.S. Public Health Service. This work was conducted by researchers in the Intramural Research Program of the National Cancer Institute, National Institutes of Health.
Acknowledgements We are grateful to the radiologic technologists who participated in the cohort study of U.S. Radiologic Technologists, Jerry Reid of the American Registry of Radiologic Technologists for continued support of this research project, Diane Kampa of the University of Minnesota for study management, and Chris McClure of Research Triangle Institute for assessment of mortality outcomes. We also thank Drs. John Boice and Jack Mandel, who played key roles in establishing the epidemiologic follow-up study of U.S. radiologic technologists.
- Interventional radiography
- Occupational radiation exposure
- Radiologic technologists