Objective: 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).
Methods: Plasma levels of Lp(a) were measured in 68 patients with APS (42 primary, 26 secondary to systemic lupus erythematosus).
Results: 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.
Conclusion: 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.