Prediction of bleeding events in patients with venous thromboembolism on stable anticoagulation treatment

Abstract

Attempts at identifying patients with an elevated risk of bleeding while on anticoagulation following acute venous thromboembolism (VTE) have largely been unsuccessful thus far. We sought to develop a clinical prediction score for bleeding during stable anticoagulation treatment after acute VTE.We performed a post hoc analysis of the pooled RE-COVER studies, two double-blind randomised "sister" trials evaluating dabigatran versus standard treatment in 5107 VTE patients.A score was derived from patients randomised to dabigatran using logistic regression analysis covering the complete follow-up period. The final model, named VTE-BLEED, included six variables and yielded a c-statistic of 0.72 (95% CI 0.67-0.76). Patients from the derivation cohort in the low-risk group (<2 points; 74% of the derivation population) had a bleeding incidence of 2.8% compared to 12.6% in the elevated-risk group (OR 5.0; 95% CI 3.5-7.1). The score proved accurate for our primary end-point, i.e. prediction of major bleeding after day 30 ("stable" anticoagulation), both in patients on dabigatran (c-statistic 0.75, 95% CI 0.61-0.89) and those on warfarin (0.78, 95% CI 0.68-0.86; p=0.77 for difference).The new VTE-BLEED score accurately predicted major bleeding events in VTE patients on stable anticoagulation with both dabigatran and warfarin.