Characterization of radiation risk associated with computed tomography for the Russian patients using disability-adjusted life years measure

Abstract

adiation risks assessment in medical exposure of patients is one of the mandatory steps in justifying the medical radiological examinations. The main objectives of such assessment are the need for benefit-harm analysis, when prescribing a study, and informing patients or their legal representatives about the radiation risk associated with the recommended examination. The traditional approach to radiation risk assessment is the use of measures based on lifetime morbidity and/or mortality due to radiation exposure in risk characterization. However, the development of the methodology of population health assessment and the need to harmonize the methodology of radiation risk assessment with risks from exposure to factors of other nature imply the use of more informative generalized health indicators in the assessment of exposure to harmful environmental factors. The aim of actual work was to apply the developed methodology of radiation detriment assessment to characterize the risk by calculating DALY (number of years of healthy full life lost due to exposure to ionizing radiation) values for different sex and age groups of Russian patients undergoing computed tomography. To achieve this goal, the previously developed method of estimating the number of years of healthy life lost due to exposure to ionizing radiation was used. Calculations were performed with the use of a specially developed computer program based on the models of the International Commission on Radiological Protection using medical and demographic data of Russian population. The article presents the results of DALY calculation for six types of computed tomographic examinations. The use of DALY to characterize risk instead of the most widely used value of radiation detriment (or lifetime risk of death, relating the harm from the reduction in the quality of life in the case of non-fatal oncological disease) is an attempt to harmonize the methodology of radiation risk assessment with the methodologies of other kind of health risks. One of the directions of calculation results usage is the development of sexand age-dependent risk coefficients associated with medical exposure of patients. The analysis of the obtained results showed that the age distribution of risks agrees well with the data presented in the methodological recommendations MR 2.6.1.0215-20 “Assessment of radiation risk to patients in radiology examinations”. It is also shown that the DALY indicator can serve as a basis for comparative assessment of obtainable and avoidable risks in the field of medical radiation exposure of patients.