Effect of statins on platelet function in patients with hyperlipidemia

Introduction: It is generally assumed that cholesterol reduction by statins is the predominant therapeutic result underlying their beneficial effects in cardiovascular disease. However, the action of statins may be partially independent of their effects on plasma cholesterol levels, as they combine lipid lowering with positive effects on hemorheological conditions and endothelial function. We evaluated the impact of statin treatment on platelet adhesion to fibrinogen (spontaneous and ADP-activated), along with ADP, collagen or ristocetin-induced aggregation in type II hyperlipidemic patients. Material and methods: The study group included 70 persons: 50 patients affected by type II hyperlipidemia without concomitant diseases and 20 healthy volunteers. The effects of 8-week statin treatment (atorvastatin 10 mg/day, simvastatin 20 mg/day, or pravastatin 20 mg/day) on platelet activation were evaluated. Results: Regardless of the type of statin, a significant decrease in ADP-induced platelet aggregation was observed: for atorvastatin 50.6 +/- 12.8% vs. 41.1 +/- 15.8% (p < 0.05), for simvastatin 57.2 +/- 18.0% vs. 44.7 +/- 22.1% (p = 0.05), and for pravastatin 55.8 +/- 19.5% vs. 38.8 +/- 23.3% (p < 0.05). There was no significant effect of statins on collagen or ristocetin-induced platelet aggregation and adhesion. Conclusions: Therapy with statins beneficially modifies ADP-induced platelet aggregation in patients with hyperlipidemia and does not affect spontaneous or ADP-induced platelet adhesion to fibrinogen and platelet aggregation induced by collagen or ristocetin.