Thrombophilic Defects (thrombophilic + defect)

Distribution by Scientific Domains


Selected Abstracts


Family history and inherited thrombophilia

JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 10 2006
G. L. VAN SLUIS
Summary.,Background: It is a common belief that patients with venous thrombosis and a positive family history for venous thromboembolism (VTE) have an increased likelihood of having an inherited thrombophilic defect. Methods: We analyzed the relation between family history, qualified with three different methods, and thrombophilic status in 314 patients with proven VTE. A positive family history (one or more first-degree relatives with VTE) and a strongly positive family history (two or more first-degree relatives with VTE). In 118 of the patients a third, more precise method was analyzed: the family history score, which compares the observed and the expected number of first-degree family members with VTE. Results: Patients with a positive or strongly positive family history had a slightly increased chance of having inherited thrombophilia compared to those without a positive family history. For positive family history this was 42% vs. negative 32%, likelihood ratio 1.3 (95% confidence interval; CI 0.9,2.1) and for strongly positive family history this was 46% vs. negative 34%, likelihood ratio 1.6 (95% CI 0.7,3.3). The family history score correlated with the chance of having inherited thrombophilia [OR 1.23 per score point (95% CI 1.01,1.48)]. However, even with this method the chance of having inherited thrombophilia is lower than 50% in 97% of the cases. Conclusions: Family history of VTE is not a precise tool in clinical practice to identify patients with inherited thrombophilia among patients with VTE. The family history score is more precise, but probably only useful for research purposes and not for daily practice. [source]


PAI-1 promoter 4G/5G genotype as an additional risk factor for venous thrombosis in subjects with genetic thrombophilic defects

BRITISH JOURNAL OF HAEMATOLOGY, Issue 1 2000
Rafael Seguí
Impaired fibrinolysis as a result of increased plasminogen activator inhibitor-1 (PAI-1) levels in plasma is a common finding in patients with deep vein thrombosis (DVT). A 4G/5G polymorphism in the promoter region of the PAI-1 gene has been reported to influence the levels of PAI-1. The 4G allele was found to be associated with higher plasma PAI-1 activity (act), but contradictory results on the incidence of the 4G allele in DVT patients have been reported. The aim of this study was to analyse whether the PAI-1 promoter 4G/5G genotype increases the risk of venous thrombosis in subjects with thrombophilic defects, and to determine the distribution of the PAI-1 4G/5G genotype and its relation to plasma PAI-1 levels in 190 unrelated patients with DVT in comparison with a control group of 152 healthy subjects. No differences between the 4G/5G allele distribution in the DVT group (0·43/0·57) and in the control group (0·42/0·58) were observed. However, the presence of the 4G allele significantly increased the risk of thrombosis in patients with other thrombophilic defects. Significantly higher PAI-1 levels were observed in DVT patients than in the controls. Our results also showed significant differences in the plasma levels of PAI-1 antigen (ag) and PAI-1 act among the 4G/5G genotypes in DVT patients. A multivariate analysis revealed that, in the DVT group, PAI-1 ag levels were influenced by the 4G allele dosage, triglyceride levels and body mass index (BMI). The influence of the 4G allele dosage on PAI-1 levels was independent of the triglyceride levels and BMI. In the control group, no significant correlation between PAI-1 levels and 4G allele dosage was observed. In conclusion, the PAI-1 promoter polymorphism was found to have an influence on PAI-1 levels in DVT patients and on the risk of venous thrombosis in subjects with other genetic thrombophilic defects. [source]