BACKGROUND: Atorvastatin 80 mg is recommended in patients with coronary artery disease to reduce cardiovascular events, however, there is controversy regarding the pharmacokinetic interactions between high doses of statins and the concomitant use of clopidogrel, since they share the same biotransformation pathway. This study evaluated the effects of the atorvastatin/clopidogrel combination therapy on the pharmacokinetics of statins and on platelet function of patients with stable coronary artery disease receiving chronic statins METHOD: Patients were admitted four times (V1 to V4) to a day-clinic. Statin was discontinued seven days (D) before the first admission. Patients then received atorvastatin 80 mg (D1 to D22) and clopidogrel 75 mg/day (D8 to D29). Fasting blood samples were obtained at all time points for lipid measurements, platelet function tests (cone and plate technique), and quantification of atorvastatin plasma levels (liquid chromatography and mass spectrometry) RESULTS: The discontinuation of statins for one week changed the lipid profile (P < 0.05 vs. baseline), with an early improvement of all lipid parameters after the administration of atorvastatin 80 mg (P < 0.005; V1 > V2, V3 and V4). Platelet adhesion was lower with clopidogrel alone (P = 0.003; V4 < V1, V2 and V3), whereas platelet aggregation values were lower following the atorvastatin/clopidogrel combination therapy or clopidogrel alone when compared to the other time points (P < 0.0001; V3 and V4 < V1 and V2). The use of clopidogrel did not affect atorvastatin serum levels CONCLUSION: High-dose atorvastatin did not affect platelet responses to clopidogrel, however the short-term statin discontinuation worsened the lipid profile and platelet function.
Platelet aggregation; Pharmacokinetics; Cardiovascular diseases
