The Evaluation of Indices of Morbidity and Mortality of Various Types of Stroke in Cohort of Workers Underwent Occupational Irradiation

Abstract

The purpose of study. To evaluate indices of morbidity and mortality of various types of strokes in the cohort of workers of the nuclear industry enterprise of the Ural Federal Okrug exposed to occupational prolonged irradiation. Materials and methods. The study was carried out in the cohort of 22,337 workers (25% of females) of the production association "Mayak" hired in 1948-1982 on the basis of medical dosimetry data base "Klinika" and data base "The Dosimetry System for Workers of the Production Association "Mayak" - 2008" The intensive (crude) indices and standardized indices of morbidity and mortality per 1,000 man-years were calculated. Results. The number of cases and deaths included in analysis made up to 2533 and 797 correspondingly. The most frequently occurring type of stroke is brain infarction. The largest number of cases and deaths of stroke (69% and 81% correspondingly) was registered in individuals aged older than 60 years. The results of implemented study demonstrated that morbidity and mortality of stroke in the analyzed cohort of workers depended on gender, age and calendar period. Conclusions. Because cerebrovascular diseases are one of the main causes of mortality and permanent disability of population of Russia, the results of study of unique cohort will input into analysis of epidemiology of cerebrovascular diseases. Alongside with the results of other large studies they can become a basis of development of preventive programs targeted to decreasing of morbidity and mortality of cerebrovascular diseases, including contingents working in contact with sources of ionizing radiation.