Abstract 388: Body Mass Index Predicts Major leeding Risks in Patients on Warfarin
Background: Despite the lack of an optimum dosing strategy in obese patients, warfarin remains the most commonly used anticoagulant. Body mass index (BMI) > 30 has been linked to increased time to obtain a therapeutic institutionalized normalized ratio (INR) on initiation of warfarin as well as higher maintenance dose. Obese patients have higher dosage requirements, however, few studies have examined the relationship between warfarin and bleeding events in these patients.
Aim: We examined the performance of BMI in predicting the incidence of bleeding at an anticoagulation clinic (ACC) over a one year period.
Methods: 863 patients followed in an ACC were evaluated for bleeds according to BMI over a one year period. BMI was defined as weight (kg)/height (m2). CHADS2VASC scores were calculated. Major (gastrointestinal, intracerebral and retroperitoneal hemorrhage) and minor bleeding events (epistaxis, hematuria, vaginal and skin bleeds) were ascertained.
Results: 71 ( 8.2%) of the 863 patients had a bleeding event, the mean age of the cohort was 69.5 years, and 44% were females. BMI categories were normal weight (21%), overweight (38%), obese class I, (21%), II (9 %), and III (11.3%) respectively. The prevalence of major and minor bleeding events were 35.2% and 64.8% respectively. In univariate analyses, hazard ratio for major bleeding risks increased with higher obesity categories (HR 1.30, 1.85, and 1.93 for class I,II, III respectively). In multivariable adjusted model, obesity (BMI>30) significantly increased the risk of major bleeds. (HR 1.84, P<.001) (Table 1).
Conclusion: Bleeding risk is higher in obese compared to normal weight individuals who are on warfarin. Risk is higher with increasing BMI. This result suggests that BMI plays a role in bleeding events in patients on warfarin. Future studies are needed to understand the mechanism by which obesity increases bleeding risk for patients on warfarin and whether similar risk exist for the novel oral anticoagulants.
Author Disclosures: A.A. Ogunsua: None. S. Touray: None. J.K. Liu: None. J. Escobar: None. T. Ip: None. J. Gore: None.
- © 2015 by American Heart Association, Inc.