Familial thrombophilia and lifetime risk of venous thrombosis
Article first published online: 9 JUL 2004
Journal of Thrombosis and Haemostasis
Volume 2, Issue 9, pages 1526–1532, September 2004
How to Cite
Vossen, C. Y., Conard, J., Fontcuberta, J., Makris, M., Van Der Meer, F. J. M., Pabinger, I., Palareti, G., Preston, F. E., Scharrer, I., Souto, J. C., Svensson, P., Walker, I. D. and Rosendaal, F. R. (2004), Familial thrombophilia and lifetime risk of venous thrombosis. Journal of Thrombosis and Haemostasis, 2: 1526–1532. doi: 10.1111/j.1538-7836.2004.00852.x
- Issue published online: 26 AUG 2004
- Article first published online: 9 JUL 2004
- Received 11 November 2003, accepted 1 April 2004
- genetic risk factors;
- venous thrombosis
Summary Background : We started a large multicenter prospective follow-up study to provide reliable risk estimates of venous thrombosis in families with various thrombophilic defects.
Objectives : This paper describes data collected at study entry on venous events experienced before study inclusion, i.e. the baseline data.
Patients/methods : All individuals (probands, relatives) registered in nine European thrombosis centers with the factor (F)V Leiden mutation, a deficiency of antithrombin, protein C or protein S, or a combination of these defects, were enrolled between March 1994 and September 1997. As control individuals, partners, friends or acquaintances of the thrombophilic participants were included. Incidence and relative risk of objectively confirmed venous thrombotic events (VTEs) prior to entry were calculated for the relatives with thrombophilia and the controls.
Results : Of the 846 relatives with thrombophilia (excluding probands), 139 (16%) had experienced a VTE with an incidence of 4.4 per 1000 person years. Of the controls, 15 of the 1212 (1%) controls had experienced a VTE with an incidence of 0.3 per 1000 person years. The risk of venous thrombosis associated with familial thrombophilia was 15.7 (95% CI 9.2–26.8) and remained similar after adjustment for regional and sex-effects (16.4; 95% CI 9.6–28.0). The highest incidence per 1000 person years was found in relatives with combined defects (8.4; 95% CI 5.6–12.2), and the lowest incidence was found in those with the FV Leiden mutation (1.5; 95% CI 0.8–2.6).
Conclusions : Considerable differences in the lifetime risk of VTE were observed among individuals with different thrombophilia defects.