Factors That Predict Risk of Thrombosis in Relatives of Patients With Unprovoked Venous Thromboembolism.
Chest. 2009 Jul 10;
Authors: Couturaud F, Leroyer C, Julian JA, Kahn SR, Ginsberg JS, Wells PS, Douketis JD, Mottier D, Kearon C
BACKGROUND: Factors that predict risk of venous thromboembolism in the first-degree relatives of patients with unprovoked venous thromboembolism are uncertain but important for counseling. We aimed to identify risk factors for, and quantify the risk of, venous thromboembolism in first-degree relatives of patients (index cases) with a first episode of unprovoked venous thromboembolism. METHODS: In a cross-sectional study, using a standardized method and without knowledge of whether patients or their relatives had thrombophilia, we assessed the prevalence of previous venous thromboembolism in 1916 first-degree relatives of 378 unselected patients with a first episode of unprovoked venous thromboembolism. Patient characteristics, and the presence of factor V Leiden or the G20210A prothrombin gene mutation in patients, were assessed as predictors of venous thromboembolism in patient's relatives. RESULTS: There were 102 previous episodes of venous thromboembolism in the first-degree relatives (prevalence of 5.3%). Thrombosis at a young age in patients was the strongest predictor of venous thromboembolism in relatives, with an adjusted odds ratio for younger patients (< 45 years of age when venous thromboembolism occurred; lowest quartile) compared with older patients (> 71 years of age; highest quartile) of 3.27 (95% confidence interval [CI], 1.68 to 6.38). Presence of factor V Leiden or the G20210A prothrombin gene in patients was a weak independent predictor of venous thromboembolism in relatives (adjusted odds ratio = 1.48; 95%CI, 0.94 to 2.33). CONCLUSION: Unprovoked venous thromboembolism at a young age is associated with a substantially increased risk of venous thromboembolism in patients' families.
PMID: 19592474 [PubMed - as supplied by publisher]