title: Risk of bleeding during long-term anticoagulation with warfarin: a tertiary care center experience.
abstract: The risk of recurrent venous thromboembolism (VTE) must be weighed against the risk of bleeding in deciding to keep patients on extended anticoagulation with vitamin K antagonists (VKAs). Most of the studies of risk of bleeding on VKAs are randomized controlled trials of highly selected patients followed for less than 1 year. We sought to determine the rate of bleeding in 'real world' patients on long-term anticoagulation with VKAs for VTE. We conducted a retrospective cohort study of patients monitored at our anticoagulation clinic who were treated with prolonged anticoagulation (>1 year) for secondary VTE prevention to assess the incidence of significant bleeding in this population. We found that most of our patients had serious comorbidities, including diabetes, cancer and solid-organ transplantation. The overall rate of bleeding was 10 episodes per 100 person-years, with major bleeding 5.2 episodes per 100 person-years. The rate of significant bleeding while on long-term warfarin may be higher than what is anticipated based on outcomes from closely controlled trials.
authors.affiliation: Division of Hematology, Oncology and Transplantation, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, USA.
authors.forename: Fatima
authors.initials: F
authors.lastname: Khan
authors.forename: Yvonne H
authors.initials: YH
authors.lastname: Datta
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000009:adverse effects* / Q000627:therapeutic use; D015331:Cohort Studies; D005260:Female; D006470:Hemorrhage / Q000139:chemically induced*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D012306:Risk; D054556:Venous Thromboembolism / Q000517:prevention & control*; D014859:Warfarin / Q000009:adverse effects* / Q000627:therapeutic use
chemical_list: D000925:Anticoagulants; D014859:Warfarin