thromboplastin and Sickle-Cell-Trait

Plasma levels of the fibrinogen degradation product D-dimer are higher among African Americans (AAs) compared with those of European ancestry and higher among women compared with men. Among AAs, little is known of the genetic architecture of D-dimer or the relationship of D-dimer to incident cardiovascular disease.. These results highlight D-dimer as an important predictor of cardiovascular disease risk in AAs and suggest that sex-specific and African ancestral genetic effects of the

Topics: Adult; Aged; Aged, 80 and over; Biomarkers; Black or African American; Cardiovascular Diseases; Female; Fibrin Fibrinogen Degradation Products; Genetic Predisposition to Disease; Genome-Wide Association Study; Hemoglobins, Abnormal; Humans; Incidence; Male; Middle Aged; Molecular Epidemiology; Phenotype; Prognosis; Prospective Studies; Risk Assessment; Risk Factors; Sex Factors; Sickle Cell Trait; Thromboplastin; Time Factors; United States; Young Adult

Recent epidemiologic data suggest that sickle cell trait (HbAS; AS) is a risk factor for venous thromboembolism. We conducted an exploratory study of healthy subjects with AS under baseline conditions to determine whether a chronic basal hyperactivation of coagulation exists, and if so, what mechanism(s) contribute to this state. Eighteen healthy AS individuals were compared to 22 African-American controls with a normal haemoglobin profile (HbAA; AA) and 17 patients with sickle cell disease (HbSS; SS). Plasma thrombin-antithrombin complexes and D-dimer levels were elevated in AS relative to AA patients (P = 0·0385 and P = 0·017, respectively), and as expected, were much higher in SSversusAA (P < 0·0001 for both). Thrombin generation in platelet poor plasma was indistinguishable between AA and AS subjects, whereas a paradoxical decrease in endogenous thrombin potential was observed in SS (P ≤ 0·0001). Whole blood tissue factor was elevated in SS compared to AA (P = 0·005), but did not differ between AA and AS. Plasma microparticle tissue factor activity was non-significantly elevated in AS (P = 0·051), but was clearly elevated in SS patients (P = 0·004) when compared to AA controls. Further studies in larger cohorts of subjects with sickle cell trait are needed to confirm the results of this preliminary investigation.

Topics: Adult; Anemia, Sickle Cell; Antithrombin III; Black or African American; Case-Control Studies; Cell-Derived Microparticles; Cytokines; Female; Fibrin; Fibrin Fibrinogen Degradation Products; Humans; Inflammation Mediators; Male; Middle Aged; Peptide Hydrolases; Plasma; Sickle Cell Trait; Thrombin; Thrombophilia; Thromboplastin; Venous Thromboembolism