Pharmacodynamic effects of adjunctive high dose atorvastatin on double dose clopidogrel in patients with high on-treatment platelet reactivity depending on diabetes mellitus status.

Diabetes mellitus (DM) is associated with impaired platelet response to clopidogrel. In patients with high on-treatment platelet reactivity (HTPR) while on standard-dose clopidogrel, high-dose atorvastatin enhances the pharmacodynamic (PD) effects of double-dose clopidogrel. It is unknown if similar effects are achieved in patients with DM. This study compare the PD effects of high-dose atorvastatin associated with double dose clopidogrel in HTPR patients with and without DM undergoing elective percutaneous coronary intervention (PCI). This is a post hoc analysis of a prospective randomized PD study that compared double-dose (150 mg) clopidogrel associated with high-dose (80 mg) atorvastatin to double-dose clopidogrel alone in statin naïve patients with HTPR undergoing elective PCI. In this analysis, patients were divided in two groups according to DM (n = 27) and non-DM (n = 49) status. Platelet reactivity was evaluated immediately before PCI and at 30 days using the VerifyNow P2Y12 assay. HTPR was defined as P2Y12 reaction units (PRU) ≥235. Administering high-dose atorvastatin in addition to high-dose clipodogrel, the 30 days absolute PRU changes (106 ± 75 vs 100 ± 42, p = 0.7) and optimal response rates (83 vs 84%; p = 0.9) were similar in DM and non-DM patients. The baseline variables significantly associated with 30-day optimal response to high-dose clopidogrel were: atorvastatin treatment (OR = 7.5 [95% CI 1.19-47]; p = 0.032) in DM patients; PRU values (OR = 0.9 [95% CI 0.95-0.99]; p = 0.031) and creatinine clearance (OR = 1.07 [95% CI 1.008-1.13]; p = 0.025) in non-DM patients. High-dose atorvastatin significantly improved the PD effects of double-dose clopidogrel in DM patients with HTPR undergoing elective PCI.