title: Risk of lower extremity arterial disease in a cohort of workers occupationally exposed to ionizing radiation over a prolonged period.
abstract: In this study the incidence risk of lower extremity arterial disease (LEAD; international classification of diseases version 9 code 440.2) was assessed in a cohort of workers occupationally exposed to radiation over a prolonged period. The study cohort includes 22,377 workers of the Mayak Production Association (25% of whom are females) first employed at one of the main facilities in 1948-1982 and followed up to the end of 2008. Dose estimates used in the study are provided by Mayak Worker Dosimetry System 2008. The mean total dose from external gamma-rays is 0.54 Gy for males and 0.44 Gy for females. The mean absorbed liver dose from internal alpha-radiation due to incorporated plutonium is 0.23 Gy in males and 0.44 Gy in females. Relative risks and excess relative risks per unit dose (ERR/Gy) are calculated based on maximum likelihood. A total of 943 cases of LEAD are registered in the study cohort during the follow-up of 512,801 person-years. A significant association of LEAD incidence with total dose from external gamma-rays (based on a linear model) was revealed, and the ERR/Gy is 0.27 (95% confidence interval (CI) 0.11; 0.48). It turned out that a linear-exponential model provides a better fit of the data (∆AIC = 9.957). Inclusion of an adjustment for internal alpha-radiation dose resulted in the reduction of the ERR/Gy to 0.19 (95% CI 0.05; 0.39), but the risk remains significant. No association of LEAD incidence with dose from internal alpha-radiation was found in the study worker cohort. It is concluded that this study provides evidence for an association of LEAD incidence with dose from external gamma-rays taking non-radiation factors into account.
authors.affiliation: Southern Urals Biophysics Institute, Ozyorskoe Shosse 19, Ozyorsk Chelyabinsk Region, Russia, 456780. clinic@subi.su.
authors.forename: Tamara V
authors.initials: TV
authors.lastname: Azizova
authors.affiliation: Southern Urals Biophysics Institute, Ozyorskoe Shosse 19, Ozyorsk Chelyabinsk Region, Russia, 456780.
authors.forename: Maria V
authors.initials: MV
authors.lastname: Bannikova
authors.affiliation: Southern Urals Biophysics Institute, Ozyorskoe Shosse 19, Ozyorsk Chelyabinsk Region, Russia, 456780.
authors.forename: Evgenia S
authors.initials: ES
authors.lastname: Grigorieva
authors.affiliation: Southern Urals Biophysics Institute, Ozyorskoe Shosse 19, Ozyorsk Chelyabinsk Region, Russia, 456780.
authors.forename: Yaroslava P
authors.initials: YP
authors.lastname: Bagaeva
authors.affiliation: Southern Urals Biophysics Institute, Ozyorskoe Shosse 19, Ozyorsk Chelyabinsk Region, Russia, 456780.
authors.forename: Elena V
authors.initials: EV
authors.lastname: Azizova
mesh_terms: D000512:Alpha Particles / Q000009:adverse effects*; D001158:Arteries / Q000528:radiation effects*; D015331:Cohort Studies; D005260:Female; D005720:Gamma Rays / Q000009:adverse effects*; D006801:Humans; D035002:Lower Extremity / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects*; D011832:Radiation Injuries / Q000453:epidemiology* / Q000209:etiology; D011874:Radiometry; D012306:Risk; D014652:Vascular Diseases / Q000453:epidemiology* / Q000209:etiology
keywords: Alpha-radiation; Atherosclerosis; Circulatory diseases; Gamma-rays; Incidence; Mayak PA; Prolonged occupational exposure