Effects of Different Doses of Ticagrelor on Platelet Aggregation and Endothelial Function in Diabetic Patients With Stable Coronary Artery Disease

Ticagrelor is an oral, reversibly-binding, direct-acting P2Y12 receptor antagonist used clinically for the prevention of atherothrombotic events in patients with acute coronary syndromes (ACS). Guideline recommendations on the use of dual antiplatelet therapy have been formulated that ticagrelor 90 mg twice daily plus aspirin in preference to clopidogrel 75mg daily plus aspirin for ACS patients. However, few East Asian patients have been included in these trials to assess the use of these drugs. In addition, a growing body of data supported that East Asian might have different adverse event profiles (thrombophilia and bleeding) and "therapeutic window" compared with white subjects. But it is still not clear whether a low dose of ticagrelor is superior to clopidogrel in diabetic patients with stable coronary disease. Recent studies found that antiplatelet drugs might have anti-inflammatory effects and protect endothelial function. ACS patients treated by ticagrelor had a significantly higher increase in levels of circulating progenitor cells compared to those treated by clopidogrel, suggesting a benefit on endothelial regeneration that may participate in the pleiotropic property of the drug. This may prompt the regression of blood vessels and the endothelium stability. But it is not very clear that the effect of low-dose ticagrelor on vascular endothelial function in diabetic patients with stable coronary artery disease. Therefore, the investigators performed this randomized, single-blind clinical trial to observe the effects of different doses of ticagrelor and standard-dose clopidogrel on platelet aggregation and endothelial function in diabetic patients with stable coronary artery disease.