title: Genetic polymorphisms and risk of recurrent deep venous thrombosis in young people: prospective cohort study.
abstract: OBJECTIVE
  To determine the incidence of deep venous thrombosis (DVT) recurrence in young people, and its association with some genetic polymorphisms (FV G1691A, FII G20210A, MTHFR C677T, PAI-1 4G/5G).
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  A database was established prospectively to follow-up a cohort of unselected patients who had had a first episode of objectively proven DVT under the age of 40 years. All patients had DNA analysis for heritable thrombophilia. We excluded patients with deficiency of antithrombin, protein C or protein S, malignant disease, antiphospholipid syndrome, or a requirement for long-term antithrombotic treatment. The end-point was objective evidence of symptomatic DVT recurrence.
  
  
  RESULTS
  Eighty-seven patients were enrolled in the study. Mean duration of follow-up was 4.07 years. At 2 years, the cumulative recurrence rate was 19.3%. The risk of risk was not related to presence or absence of laboratory evidence of genetic polymorphisms: FV G1619A (HR 1.26 [95%CI: 0.64-2.46]; p = 0.51), FII G20210A (HR 0.81 [95%CI: 0.35-1.89]; p = 0.62), MTHFR C677T (HR 1.26 [95%CI: 0.56-2.81]; p = 0.58), PAI-1 4G/5G (0.84 [95%CI: 0.35-2.05]; p = 0.71).
  
  
  CONCLUSIONS
  In this study, the risk of recurrent deep venous thrombosis in young people was not related with the presence of FV G1691A, FII G20210A, MTHFR C677T or PAI-1 4G/5G polymorphisms.
authors.affiliation: Department of Vascular Surgery, S. João University Hospital, Porto, Portugal. mansilha@netcabo.pt
authors.forename: A
authors.initials: A
authors.lastname: Mansilha
authors.forename: F
authors.initials: F
authors.lastname: Araújo
authors.forename: M
authors.initials: M
authors.lastname: Severo
authors.forename: S M
authors.initials: SM
authors.lastname: Sampaio
authors.forename: T
authors.initials: T
authors.lastname: Toledo
authors.forename: R
authors.initials: R
authors.lastname: Albuquerque
mesh_terms: D045103:5,10-Methylenetetrahydrofolate Reductase (FADH2) / Q000235:genetics; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001779:Blood Coagulation Factors / Q000235:genetics; D005260:Female; D005500:Follow-Up Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D009154:Mutation; D011110:Polymorphism, Genetic; D011446:Prospective Studies; D012008:Recurrence; D020246:Venous Thrombosis / Q000235:genetics*
chemical_list: D001779:Blood Coagulation Factors; D045103:5,10-Methylenetetrahydrofolate Reductase (FADH2)