Elevated plasma lipoprotein(a) level and its association with impaired fibrinolysis in patients with antiphospholipid syndrome.

Abstract

To assess the significance of lipoprotein(a) [Lp(a)], a risk factor for atherothrombosis, and its relationship with fibrinolysis in a cohort of patients with antiphospholipid syndrome (APS). Plasma levels of Lp(a) were measured in 68 patients with APS (42 primary, 26 secondary to systemic lupus erythematosus). Elevated plasma levels of Lp(a) were found in patients with APS compared to 22 healthy controls (p = 0.0001). The significance persisted after comparing Lp(a) levels in 3 APS subgroups (arterial thrombosis, n = 37; venous thrombosis, n = 31; recurrent miscarriages, n = 24) with those of controls (p < 0.0001). Patients with APS with maximal elevation of Lp(a) showed a lower fibrinolytic activity (lower D-dimer and higher plasminogen activator inhibitor) than patients whose Lp(a) was within a normal range. These findings suggest that Lp(a) may represent a marker of APS and that Lp(a) has a negative effect on the fibrinolytic system that might contribute to the thrombotic tendency of APS.