Occupational
Occupational low-dose medical radiation exposure and risk of Parkinson’s disease mortality in the U.S. Radiologic Technologists Study Isabelle van der Velpen* Isabelle van der Velpen van der Velpen van der Velpen van der Velpen van der Velpen van der Velpen van der Velpen van der Velpen van der Velpen van der Velpen van der Velpen Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States
Objective: Parkinson’s disease (PD) is a neurological disorder that is increasing in incidence globally. Recent studies suggest that exposure to low-dose ionizing radiation may be associated with PD risk. We studied the association between occupational radiation exposure and PD mortality in a large U.S. medical worker cohort
Methods: U.S. Radiologic Technologists (USRT) Study participants (mean baseline age 41.0 years, 76.0% female) were followed from response date of the 1st (1983-1989) or 2nd survey (1994-1998) to December 31, 2021 (n=109,113). Estimated radiation absorbed dose to the brain was calculated for the exposure period 1916-2020. PD mortality included PD as any cause of death. Multivariable Poisson regression models were used to calculate excess relative rates (ERR) of PD mortality per 100 mGy, using 10-year lagged cumulative brain-absorbed dose. Multivariable Cox proportional hazards models were used to calculate hazard ratios for PD mortality associated with self-reported work history (decade first worked, total years worked per decade, procedures performed [fluoroscopically-guided interventional (FGI), nuclear medicine], number of times held patients, and ever exceeding exposure limit).
Results: During follow-up of 3,389,435 person-years, 433 PD deaths occurred. A linear dose-response relationship was observed for PD mortality (ERR/100mGy=1.53;95%CI:0.51-3.25), especially in male workers. Ever assisting with FGI procedures was associated with a higher PD mortality risk (HR=1.45;95%CI:1.06-2.00). Participants who assisted with FGI procedures daily post-1980s had a higher PD mortality risk than those who never/rarely assisted post-1980s (HR=2.58;95%CI:1.54-4.32).
Conclusion: Cumulative low-dose radiation exposure and daily assisting with FGI procedures were associated with higher PD mortality. These findings support continued efforts to limit occupational radiation exposure and provide additional support for a role of ionizing radiation in PD etiology.