Effects of pioglitazone on subclinical atherosclerosis and insulin resistance in nondiabetic renal allograft recipients

Background. The aim of this study was to evaluate the effect of pioglitazone treatment on the progression of subclinical atherosclerosis and insulin resistance in renal allograft recipients with no preoperative history of diabetes.Methods. Eighty-three patients without diabetes were randomly assigned to either the pioglitazone group or the control group. Carotid intima-media thickness (IMT), serum adiponectin level and lipid profile were assessed before transplantation and at 12 months after transplantation. Insulin secretory function and insulin resistance were evaluated by the oral glucose tolerance test.Results. The pioglitazone group showed a significant reduction in the mean and maximum carotid IMT compared with the control group after 12 months (mean carotid IMT, 0.05 ± 0.04 vs-0.03 ± 0.07mm, P < 0.001; maximum carotid IMT, 0.08 ± 0.05 vs-0.05 ± 0.09mm, P < 0.001). Pioglitazone increased the adiponectin level, and the change in adiponectin was negatively correlated with carotid IMT changes. Pioglitazone treatment increased the insulin sensitivity index compared with the control group (-0.8 ± 3.1×10^-2 vs +1.1 ± 3.7×10 ^-2, P = 0.036).Conclusions. These results suggest that pioglitazone treatment reduces the progression of carotid IMT and improves insulin resistance in renal allograft recipients without a history of diabetes.