Platelet Function Profiles in Patients With Type 2 Diabetes and Coronary Artery Disease on Combined Aspirin and Clopidogrel Treatment

Platelet Function Profiles in Patients With Type 2 Diabetes and Coronary Artery Disease on Combined Aspirin and Clopidogrel Treatment Dominick J. Angiolillo 1 , Antonio Fernandez-Ortiz 2 , Esther Bernardo 2 , Celia Ramírez 2 , Manel Sabaté 2 , Pilar Jimenez-Quevedo 2 , Rosana Hernández 2 , Raul Moreno 2 , Javier Escaned 2 , Fernando Alfonso 2 , Camino Bañuelos 2 , Marco A. Costa 1 , Theodore A. Bass 1 and Carlos Macaya 2 1 Division of Cardiology, University of Florida, Shands Jacksonville, Jacksonville, Florida 2 Cardiovascular Institute, San Carlos University Hospital, Madrid, Spain Address correspondence and reprint requests to Dominick J. Angiolillo, MD, FACC, FESC, Division of Cardiology, University of Florida, Shands Jacksonville, 655 West 8th St., Jacksonville, FL 32209. E-mail: dominick.angiolillo{at}jax.ufl.edu Abstract To assess platelet function profiles in diabetic and nondiabetic patients on aspirin and clopidogrel therapy, two patient populations were included to investigate the 1 ) acute effects of a 300-mg clopidogrel loading dose (group 1, n = 52) and 2 ) long-term effects of clopidogrel (group 2, n = 120) on platelet function in diabetic compared with nondiabetic patients already on aspirin treatment. Patients were stratified according to the presence of type 2 diabetes. Platelet aggregation was assessed using light transmittance aggregometry (groups 1 and 2). Platelet activation (P-selectin expression and PAC-1 binding) was determined using whole-blood flow cytometry (group 2). Clopidogrel response was also assessed. In group 1, platelet aggregation was significantly increased in diabetic ( n = 16) compared with nondiabetic ( n = 36) patients at baseline and up to 24 h following a 300-mg loading dose ( P = 0.005). In group 2, platelet aggregation and activation were increased in diabetic ( n = 60) compared with nondiabetic ( n = 60) subjects ( P < 0.05 for all platelet function assays). Diabetic subjects had a higher number of clopidogrel nonresponders ( P = 0.04). Diabetic patients have increased platelet reactivity compared with nondiabetic subjects on combined aspirin and clopidogrel treatment. Reduced sensitivity to antiplatelet drugs may contribute to the increased atherothombotic risk in diabetic patients. CAD, coronary artery disease GP, glycoprotein PRP, platelet-rich plasma Footnotes D.J.A. has received consulting fees from Sanofi-Aventis and Bristol-Myers Squibb. The costs of publication of this article were defrayed in part by