Using the years-of-healthy-life measure to calculate QALYs

Background: The quality-adjusted life year (QALY) is an attractive outcome measure because it captures both health-related quality of life (HRQL) and life expectancy in a single metric. We present a method for calculating QALYs that is simple, utilizes data that are free of charge, and may improve consistency in burden-of-disease investigations. Methods: For purposes of illustration, we calculated the burden of disease due to stroke using two abridged life tables, each adjusted for HRQL. The first life table was generated using all-cause mortality and morbidity data (a reference cohort) and the second was generated using all diseases except stroke (a stroke-free cohort). The difference in total QALYs and in quality-adjusted life expectancy (QALE) was determined by subtraction. Results: Approximately 61,328 (95% CI=60,272, 62,383) QALYs were lost to stroke in the life-table cohort. Stroke is responsible for a decrement of 0.03 years of life expectancy and 0.61 years of QALE in the United States. Conclusions: The “years of health life”measure affords a rapid, inexpensive, and sensitive means for estimating the burden of disease for local health priorities and may assist research efforts in including QALYs as an outcome measure