The aim of our study was to investigate insulin sensitivity and beta cell function in hemodialysis (HD) patients without diabetes. We hypothesized that parathyroid gland function was a determinant of insulin sensitivity and/or beta cell function. The study was a randomized, cross-sectional one and patients were divided into two groups (total 27 patients), Gp.1 being those with relative hypoparathyroidism (iPTH<200 pg/ml) 9 (33.3%), Gp.2 those with hyperparathyroidism (iPTH200 pg/ml) 18 (66.6%) with Gp.3 (consisting of 43 healthy subjects acting as controls). Insulin resistance and insulin secretion were calculated from fasting serum insulin and glucose concentrations by the Homeostatic Model Assessment score (HOMA IR and HOMA BETA). The value of HOMA IR (3.28±1.3 for Gp.1, 4.80±2.4 for Gp.2, 1.70±0.8 for Gp.3) as well as the glucose level (5.0±1.0mmol/l in Gp.1, 5.2±0.8mmol/ l in Gp.2, 4.6±0.4mmol/l in Gp.3) was significantly higher in HD patients than in control subjects. Excessive insulin secretion was present in HD patients (as assessed by HOMA BETA) significantly higher only in Gp.1 (p=0.02).peer-reviewe