Clinical importance of insulin resistance after renal transplantation in patients on triple immunosuppressive therapy with cyclosporine, corticosteroids and mycophenolate mofetil.

INTRODUCTION: Post-transplant diabetes mellitus and impaired glucose tolerance are confirmed complications after solid organ transplantation associated with the use of glucocorticoids and calcinuerin inhibitors in maintenance immunosuppression. Insulin resistance (IR) is also an independent factor for cardiovascular morbidity and mortality among renal allograft patients. The aim of our work was to investigate the clinical importance of elevated IR in renal transplant recipients on standard triple-drug immunosuppression in correlation with immunosuppressive therapy and certain independent factors such as body mass index (BMI), time after transplantation, lipid disorders, etc. METHODS: 36 allograft pts with different periods after transplantation without previous glucose disorders were included in the study. An oral glucose tolerance test (OGTT) was made to distinguish pts with or without glucose disorders. The basal values of glucose (G) and insulin (I) were used to calculate indexes of IR and beta-cell function according to the homeostasis equations. Impaired fasting glucose (IFG), impairred glucose tolerance (IGT), impaired post prandial hyperglycemia (IPPH) and diabetes mellitus (DM) were also analysed. RESULTS: The mean value of the IR index was 2.57 +/- 1.20. It was elevated in 31 pts (86%) The IR showed a positive correlation with: I0 (p < 0.01), I2 (p < 0.05), beta cell function (p < 0.05) and CsA (p < 0.01). The fasting I, G, and BMI were shown as independent risk factors for IR (p < 0.01, p < 0.01, and p < 0.05 respectively). There were 12 pts with different glucose disorders (IFG, IGT, DM) and 24 pts without. The pts with glucose disorders showed an elevated IR index (91%) more frequently compared with (41.67%) decreased beta-cell function. CONCLUSION: IR is frequent among renal recipients with and without glucose disorders. IR is an independent risk factor for atherogenesis. Higher CsA trough levels are assotiated with higher Insulin values and indexes of IR. The defect in insulin action is more a prominent mechanism in post-transplant glucose disorders than the impaired insulin secretion.