Burden of ischemic stroke in Korea: Analysis of disability-adjusted life years lost

Background and Purpose Disability-adjusted life years (DALY), incorporating both disability and mortality, has been widely employed to measure regional and global burdens of stroke. Thus far, the DALY lost to stroke in a population has been estimated using only the crude population-level data; no previous study has incorporated refined data from stroke registries. The aim of this study was to integrate the stroke registry data and the population-level incidence data to project the nationwide DALY lost to ischemic stroke. Methods From the data of two large ischemic stroke registries, we derived an average DALY lost due to ischemic stroke for each of the following age groups: <45, 45-54, 55-64, 65-74, 75-84, and ≥85 years. The nationwide ischemic stroke incidence for each age group was extracted from a cardiovascular and cerebrovascular surveillance study that analyzed the 2004 Korean Health Insurance database. Results The average DALY lost due to ischemic stroke for the age groups <45, 45-54, 55-64, 65-74, 75-84, and ≥85 years was 5.07, 4.63, 4.35, 3.88, 2.88, and 1.73, respectively. By multiplying the incidence and the average DALY lost, the nationwide DALY lost was determined to be 9,952 for those <45 years, 24,608 for 45-54 years, 50,682 for 55-64 years, 88,875 for 65-74 years, 52,089 for 75-84 years, and 8,192 for ≥85 years, respectively. The projected nationwide DALY lost due to 64,688 ischemic strokes in 2004 was 234,399 (121,482 for men and 113,244 for women), and the DALY lost per 100,000 person-years was 483 (500 for men and 469 for women). Conclusions Incidence data from a population study and DALY values derived from stroke registries can be integrated to provide a more refined projection of the nationwide burden of ischemic stroke. In Korea, more than 230,000 years of healthy life are being lost annually due to ischemic stroke, and hence prompt action is imperative.