Validation of a Risk Score for Dying Within 1 Year of an Admission for Heart Failure

Abstract

Background Development of heart failure greatly reduces life expectancy. Accurate estimates of the risk of dying are needed in clinical practice and for risk adjustment in observational studies. A relatively simple risk score has been developed to determine the risk of dying within 1-year of an admission for heart failure. We wanted to evaluate the risk score's predictive validity. Methods and Results Data were abstracted from the electronic medical records of 769 patients admitted to the Minneapolis Veterans Administration medical center with a primary diagnosis of heart failure. Mortality within 1 year of admission was 25%. The c-index for the risk score was 0.71 (95% confidence interval 0.67–0.76). Similar to the original derivation cohort, mortality in risk score groups was 7% for a score lower than 60 (n = 44), 14% for 61 to 90 (n = 246), 26% for 91 to 120 (n = 222), 51% for 121 to 150 (n = 106), and 50% for scores greater than 150 (n = 8). Conclusion A previously developed risk score for 1-year mortality after an admission for heart failure provided a moderate degree of discrimination in a validation cohort from a different setting. Mortality in risk score groups was consistent with the original patient cohort. These results support the validity of the risk score and its application to a different patient population.