title: Risk for subsequent venous thromboembolic complications in carriers of the prothrombin or the factor V gene mutation with a first episode of deep-vein thrombosis.
abstract: Carriers of a mutation in the prothrombin (clotting factor II) or factor V gene have a 2- to 4-fold greater risk for venous thromboembolism than subjects without the mutations. Whether both mutations also predispose to recurrent venous thromboembolism is unclear. Outpatients who had a first episode of proven symptomatic deep-vein thrombosis and a long-term follow-up were studied. The outcome measure was the cumulative incidence of confirmed venous thromboembolic complications. Two hundred fifty-one patients were enrolled in the study. Mean duration of follow-up was 8.3 years. The prothrombin gene mutation was demonstrated in 27 patients (prevalence, 10.8%; 95% CI, 6.9 to 14.6), and the factor V gene mutation was demonstrated in 41 patients (prevalence, 16.3%; 95% CI, 11.8 to 20.9). The cumulative incidence of venous thromboembolic complications after 10 years was 61.3% (95% CI, 35.7 to 87.9), and the hazard ratio was 2.4 (95% CI, 1.3 to 4.7; P =.004) in patients with the prothrombin gene mutation); the cumulative incidence of venous thromboembolic complications after 10 years was 55.2% (95% CI, 36.4 to 74.0), and the hazard ratio was 2.4 (95% CI, 1.4 to 4.1; P =.001) in patients with the factor V gene mutation. In comparison, the cumulative incidence of venous thromboembolic complications after 10 years was 23.1% (95% CI, 16.2 to 30.1) in patients without the mutations. Prothrombin and factor V gene mutations occur frequently in patients with venous thrombosis and are associated with an increased risk for recurrent venous thromboembolic complications.
authors.affiliation: Department of Medical and Surgical Sciences, Second Chair of Internal Medicine, University Hospital of Padua, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Simioni
authors.forename: P
authors.initials: P
authors.lastname: Prandoni
authors.forename: A W
authors.initials: AW
authors.lastname: Lensing
authors.forename: D
authors.initials: D
authors.lastname: Manfrin
authors.forename: D
authors.initials: D
authors.lastname: Tormene
authors.forename: S
authors.initials: S
authors.lastname: Gavasso
authors.forename: B
authors.initials: B
authors.lastname: Girolami
authors.forename: C
authors.initials: C
authors.lastname: Sardella
authors.forename: M
authors.initials: M
authors.lastname: Prins
authors.forename: A
authors.initials: A
authors.lastname: Girolami
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005165:Factor V / Q000235:genetics*; D005260:Female; D005500:Follow-Up Studies; D006579:Heterozygote; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D015995:Prevalence; D011516:Prothrombin / Q000235:genetics; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D013923:Thromboembolism / Q000453:epidemiology / Q000209:etiology / Q000235:genetics*; D020246:Venous Thrombosis / Q000453:epidemiology / Q000209:etiology / Q000235:genetics*
chemical_list: D005165:Factor V; D011516:Prothrombin