Randomized control trial comparing the effect of cilostazol and aspirin on changes in carotid intima-medial thickness

Antiplatelet drugs are effective in preventing recurrence of atherosclerosis in type 2 diabetes (T2D) patients. However, the efficacy and usefulness of antiplatelet drugs on the progression of carotid intima-media thickness (IMT), a marker for evaluating early atherosclerotic vascular disease, has not been analyzed. We conducted a prospective, randomized, open, 36-month trial comparing cilostazol vs. aspirin. A total of 415 T2D patients (age range 38–83 years; 206 females) without macrovascular complications were randomized to either an aspirin (100 mg/day) or cilostazol (200 mg/day) treatment. Patients underwent B-mode ultrasonography annually to assess the IMT and serum levels of inflammatory markers were measured before and after each treatment. Potential confounders were statistically adjusted, and included lipid profiles, HbA1c, body mass index, waist circumference, anti-hypertensive and statin medications. The decrease in mean left, maximum left, mean right and maximum right IMT were significantly greater with cilostazol compared with aspirin (− 0.094 ± 0.186 mm vs. 0.006 ± 0.220 mm, p < 0.001; − 0.080 ± 0.214 mm vs. 0.040 ± 0.264 mm, p < 0.001; − 0.064 ± 0.183 mm vs. 0.004 ± 0.203 mm, p = 0.015; − 0.058 ± 0.225 mm vs. 0.023 ± 0.248 mm, p = 0.022, respectively). And these differences remained significant after adjustment of potential confounders. Compared with aspirin, cilostazol treatment was associated with significantly increased HDL cholesterol (p = 0.039) and 25-hydroxy vitamin D levels (p = 0.001). Cilostazol treatment was associated with significantly lowered IMT in T2D patients compared to aspirin, independent of conventional cardiovascular risk factors. Cilostazol may inhibit plaque formation and have beneficial effects on atherosclerosis through vasodilatory and antiplatelet effects.