This multi-center, randomized controlled study aims to evaluate the efficacy of Cilostazol versus Aspirin for primary prevention of atherosclerotic events with Korean type 2 Diabetes Mellitus (DM) patients.

Inclusion Criteria:

1. Type 2 diabetes mellitus with high risk of macrovascular complications; high risk is one or more as follows:

   • Hypertension (≧ 140/90 or anti-hypertensive therapy)
   • Hypercholesterolemia (LDL-C > 130 mg/dL or anti-hyperlipidemic therapy)
   • TG > 200 mg/dL
   • Non proliferative retinopathy or macular edema
   • Microalbuminuria or macroalbuminuria
   • Smoker

2. Patients on no anti PLT drug history

3. Patients who are agree with this research

Exclusion Criteria:

1. Type 1 diabetes mellitus
2. Macrovascular complication history
3. Uncontrolled hypertension, unstable angina history
4. Congestive heart failure
5. Bleeding tendency
6. Chronic liver disease (ALT > 100 or AST > 100) or Chronic renal disease creatinine > 3.0 mg/dl)
7. Anemia (hemoglobin < 10 mg/dl) or thrombocytopenia (platelet count less than 100,000/mm3)
8. Pregnant or lactation women
9. Plan to be revascularized in 4 weeks
10. Plan to go to surgery or invasive intervention in 4 weeks
11. Plan to need to admission for acute cardiovascular disease in 4 weeks
12. Contraindication of this medication
13. Other anti-PLT drug therapy