Abstract 15722: Validity of HAS-BLED Score in Prediction of Major Bleeding Risk in Patients with Atrial Fibrillation Taking Warfarin and Dabigatran

Abstract

Introduction Warfarin and dabigatran are used to prevent thromboembolism in patients with atrial fibrillation (AF). Although these medications can effectively prevent ischemic stroke, they are associated with major hemorrhage. The HAS-BLED scoring system was developed in 2010 from “The Euro Heart Survey” to predict the risk of major bleeding in patients taking oral warfarin. However, there are few studies that evaluate the use of HAS-BLED with newer agents, such as dabigatran. Our goal was to validate the HAS-BLED score as a predictor of the risk of major bleeding in patients with AF who are on oral warfarin and dabigatran. Hypothesis We assessed the hypothesis that the HAS-BLED index would be predictive of the risk of major bleeding in patients with AF on warfarin and dabigatran. Methods A retrospective chart review was conducted on patients with AF who were on warfarin and dabigatran. Seven hundred patients were screened; 176 patients on warfarin (Jan. 2010-Aug. 2010) and 88 patients on dabigatran (Jan. 2010-May 2012) met the inclusion criteria of a diagnosis of AF and being on oral anticoagulants for at least six months, and had outcome measures available. The HAS-BLED scoring index was applied to the 264 patients in both groups. The outcome of major bleed was determined by patient medical records and a follow-up call to their primary care doctor for any documentation of bleeding. Results Overall, 141 patients had HAS-BLED scores greater than or equal to 3. Of these, 61 patients developed a major bleed. 123 patients had HAS-BLED scores less than 3; of which, 1 developed a major bleed. The sensitivity was 98.4% and the specificity was 60.4%. The prevalence of major bleed in our population was 23.5%. In the dabigatran only group, 27 subjects had score greater or equal to 3; of which 13 developed a major bleed. 61 patients had score below 3; of which, 1 developed a major bleed. The sensitivity was 92.9% and the specificity 81.1%. Conclusion In conclusion, our findings suggest that the HAS-BLED index is a good predictor of the risk of major bleeding in patients on anticoagulants, for both warfarin and dabigatran. Prospective studies with large study samples are recommended to support these findings, specifically for further validation of the use of HAS-BLED in relation to dabigatran.