BACKGROUND: The Outpatient Bleeding Risk Index (BRI) prospectively classified patients who were at high, intermediate, or low risk for
warfarin-related major bleeding. However, there are only 2 published validation studies of the index and neither included
veterans.
OBJECTIVE: To determine the accuracy of the BRI in patients attending a Veterans Affairs (VA) anticoagulation clinic and to speifically
evaluate the accuracy of the BRI in patients with atrial fibrillation.
DESIGN: Retrospective cohort study.
PATIENTS AND MEASUREMENTS: Using the BRI, all patients managed by the Anticoagulation Clinic between January 1, 2001 and December 31, 2002 were classified
as high, intermediate, or low risk for major bleeding. Bleeds were identified via quality-assurance reports. Poisson regression
was used to determine whether there was an association between the index and the development of bleeding.
RESULTS: The rate of major bleeding was 10.6%, 2.5%, and 0.8% per patient-year of warfarin in the high-, intermediate-, and low-risk
groups, respectively. Patients in the high-risk category had 14 times the rate of major bleeding of those in the low-risk
group (incidence rate ratio (IRR) 14; 95% confidence interval (CI), 1.9 to 104.7). The rate of major bleeding was significantly
different between the high- and intermediate-risk categories (P<.001). Among those with atrial fibrillation, patients in the high-risk category had 6 times the major bleeding rate of those
in the intermediate- and low-risk groups combined (IRR=6; 95% CI, 2.4 to 15.3).
CONCLUSIONS: The BRI discriminates between high- and intermediate-risk patients in a VA anticoagulation clinic, including those with atrial
fibrillation.
Key Words bleeding risk - warfarin - anticoagulation clinic
The authors have no conflicts of interest to declare for this article or this research.
At the time of the study, Dr. DeSanzo was a pharmacy practice resident at the VA Pittsburgh Healthcare System.