Glucose Intolerance Is Associated With Increased Intimal-Medial Thickness of the Carotid Artery and Increased Pulse-Wave Velocity in Renal Transplant Recipients

Abstract

BackgroundAlthough new-onset diabetes after transplantation has been demonstrated to have a significant negative impact on allograft and patient survival, the role of glucose intolerance (impaired fasting glucose [IFG] and/or impaired glucose tolerance [IGT], as asymptomatic hyperglycemia and borderline diabetes, has not been identified in renal transplant recipients. MethodsWe enrolled 32 renal transplant recipients (at least 1year after transplantation) without prior evidence of diabetes at our institution in this study. Transplant recipients were divided into 2 groups (normal glucose tolerance group and glucose intolerance group) according to the results of their oral glucose tolerance test with 75 g of glucose. Glucose intolerance included IFG, IGT, and IFG/IGT. Normal glucose tolerance was detected in 19 patients, and glucose intolerance in 13: had 6 IGT, 2 IFG, and 5 IGT/IFG. Bilateral brachial-ankle pulse-wave velocity (baPWV) and intimal-media thickness (IMT) measured as markers of atherosclerosis were compared between the 2 groups. Insulin resistance was estimated with the homeostasis model assessment of insulin resistance (HOMA-R), and pancreatic β-cell function evaluated by the homeostasis model assessment of β-cell function and insulinogenic index. ResultsThe patients in the glucose intolerance group showed significantly greater baPWV and IMT than those in the normal glucose tolerance group. HOMA-R in the glucose intolerance patients was significantly higher than in the normal glucose tolerance patients. Linear regression analysis showed the increased IMT in the renal transplant recipients to be significantly correlated with HOMA-R. ConclusionsRenal transplant recipients with glucose intolerance had increased IMT and baPWV, suggesting that glucose intolerance in renal transplant recipients may induce atherosclerosis and that the rise in insulin resistance may contribute to the increased IMT in renal transplant recipients.