Decrease in carotid intima media thickness after 1 year of cilostazol treatment in patients with type 2 diabetes mellitus

A multicenter exploratory study at three university hospitals was performed to evaluate the effect of oral cilostazol on intima media thickness (IMT) in diabetic patients. A total of 141 patients was recruited in this study and randomized into a cilostazol group and a placebo (control) group. One hundred and twenty patients completed the study (i.e. 60 on cilostazol and 60 on placebo). Biochemical profiles and the IMT of the common carotid artery (CCA) determined by high-resolution B-mode ultrasonography were measured at 0, 6, and 12 months after the oral administration of 100-200 mg of cilostazol or placebo (i.e. two or four times daily for 12 months). Clinical and biochemical characteristics, the treatment modality, and microvascular diabetic complications after randomization were not significantly different between the two groups after the study. In the cilostazol treatment group, left CCA average IMT significantly decreased from 0.94±0.03 to 0.91±0.02 mm at 6 months (P<0.05), and thereafter increased to 0.92±0.01 mm (P>0.05) at 12 months, whereas in the control group, it increased from 0.92±0.03 to 0.93±0.01 mm at 6 months (P>0.05), and to 0.94±0.01 mm at 12 months (P>0.05). As for the right CCA average IMT, it decreased from 0.83±0.03 to 0.82±0.01 mm at 6 months (P<0.05), and to 0.81±0.01 mm at 12 months (P<0.05) in the cilostazol group, whereas it increased from 0.87±0.03 to 0.89±0.01 mm at 6 months (P<0.05), and to 0.90±0.01 mm at 12 months (P<0.05) in the control group (P<0.05). After correction for risk factors such as blood pressure, smoking, and lipid profiles, there were significant changes in left and right CCA average IMT for both groups (P<0.05). Left and right CCA average IMT was significantly different between the two groups (P<0.05). After making statistical corrections for blood pressure, smoking, and lipid profiles, the differences between these two groups remained significant (P<0.05). Meanwhile, there were no differences between the groups in the change of risk factors such as BMI, blood pressure, blood sugar, HbA_1c, and lipid profiles. Generally, cilostazol was well tolerated and the most common side effect in the cilostazol group was headache (12/60), mostly early in the treatment regimen. The results suggest that oral cilostazol may be helpful in the treatment of atherosclerosis in type 2 diabetic patients, although conventional cardiovascular risk factors remained unmodified.