title: Outcome of Patients with Venous Thromboembolism and Factor V Leiden or Prothrombin 20210 Carrier Mutations During the Course of Anticoagulation.
abstract: BACKGROUND
  Individuals with factor V Leiden or prothrombin G20210A mutations are at a higher risk to develop venous thromboembolism. However, the influence of these polymorphisms on patient outcome during anticoagulant therapy has not been consistently explored.
  
  
  METHODS
  We used the Registro Informatizado de Enfermedad TromboEmbólica database to compare rates of venous thromboembolism recurrence and bleeding events occurring during the anticoagulation course in factor V Leiden carriers, prothrombin mutation carriers, and noncarriers.
  
  
  RESULTS
  Between March 2001 and December 2015, 10,139 patients underwent thrombophilia testing. Of these, 1384 were factor V Leiden carriers, 1115 were prothrombin mutation carriers, and 7640 were noncarriers. During the anticoagulation course, 160 patients developed recurrent deep vein thrombosis and 94 patients developed pulmonary embolism (16 died); 154 patients had major bleeding (10 died), and 291 patients had nonmajor bleeding. On multivariable analysis, factor V Leiden carriers had a similar rate of venous thromboembolism recurrence (adjusted hazard ratio [HR], 1.16; 95% confidence interval [CI], 0.82-1.64), half the rate of major bleeding (adjusted HR, 0.50; 95% CI, 0.25-0.99) and a nonsignificantly lower rate of nonmajor bleeding (adjusted HR, 0.66; 95% CI, 0.43-1.01) than noncarriers. Prothrombin mutation carriers and noncarriers had a comparable rate of venous thromboembolism recurrence (adjusted HR, 1.00; 95% CI, 0.68-1.48), major bleeding (adjusted HR, 0.75; 95% CI, 0.42-1.34), and nonmajor bleeding events (adjusted HR, 1.10; 95% CI, 0.77-1.57).
  
  
  CONCLUSIONS
  During the anticoagulation course, factor V Leiden carriers had a similar risk for venous thromboembolism recurrence and half the risk for major bleeding compared with noncarriers. This finding may contribute to decision-making regarding anticoagulation duration in selected factor V Leiden carriers with venous thromboembolism.
authors.affiliation: Department of Haematology and Bone Marrow Transplantation, Rambam Health Care Campus, Haifa, Israel. Electronic address: i_tzoran@rambam.health.gov.il.
authors.forename: Inna
authors.initials: I
authors.lastname: Tzoran
authors.affiliation: Haematology and Hemostasis Unit, Hospital Papageorgiou, Saloniki, Greece.
authors.forename: Manolis
authors.initials: M
authors.lastname: Papadakis
authors.affiliation: Department of Haematology and Bone Marrow Transplantation, Rambam Health Care Campus, Haifa, Israel.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Brenner
authors.affiliation: Department of Internal Medicine, Hospital Universitario de Salamanca, Spain.
authors.forename: Ángeles
authors.initials: Á
authors.lastname: Fidalgo
authors.affiliation: Department of Pneumonology, Hospital Universitario Araba, Álava, Spain.
authors.forename: Agustina
authors.initials: A
authors.lastname: Rivas
authors.affiliation: Department of Medicine, University of Ottawa, Ottawa Hospital Research Institute, Ontario, Canada.
authors.forename: Philip S
authors.initials: PS
authors.lastname: Wells
authors.affiliation: Department of Haematology, Hospital Clínico Universitario Lozano Blesa, Zaragoza, Spain.
authors.forename: Olga
authors.initials: O
authors.lastname: Gavín
authors.affiliation: Department of Internal Medicine, Hospital de Montilla, Córdoba, Spain.
authors.forename: María Dolores
authors.initials: MD
authors.lastname: Adarraga
authors.affiliation: Department of Emergency, Clermont-Ferrand University Hospital, France.
authors.forename: Farès
authors.initials: F
authors.lastname: Moustafa
authors.affiliation: Department of Internal Medicine, Hospital Universitario Germans Trias i Pujol de Badalona, Universidad Católica de Murcia, Barcelona, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Monreal
mesh_terms: D020016:Activated Protein C Resistance / Q000150:complications*; D000925:Anticoagulants / Q000627:therapeutic use*; D005165:Factor V / Q000235:genetics*; D005260:Female; D006470:Hemorrhage / Q000139:chemically induced / Q000209:etiology / Q000235:genetics; D006579:Heterozygote; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics; D011516:Prothrombin / Q000235:genetics*; D012307:Risk Factors; D016896:Treatment Outcome; D054556:Venous Thromboembolism / Q000188:drug therapy / Q000235:genetics*
chemical_list: D000925:Anticoagulants; C095381:factor V Leiden; D005165:Factor V; D011516:Prothrombin
keywords: Anticoagulant therapy; Bleeding; Thrombophilia; Venous thromboembolism