Endocrine Abstracts

DM 2 is a genetic disorder characterized by reduced insulin action and impaired insulin secretion. Metabolism of healthy Lithuanian citizens with an inherited risk for DM 2 was compared with a control group without a family history of DM 2. 84 normotensive first degree relatives (FDR) (23M, 61F) with at least one parent or sibling with DM 2 were investigated. 89 normotensive and glucose tolerant ubjects without family history of DM 2 and with a comparable distribution of age, sex, and weight served as control (CG). The FDR had significantly higher levels of fasting glucose (5.54±0.59 vs. 5.31±0.53 mmol/l, p=0.008), fasting insulin (13.05±9.72 vs. 9.35±6.20 mUI/ml, p=0.003) and C-peptide (696.71±242.17 vs. 593.71±203.19 pmol/l, p=0.008) than CG subjects. FDR had higher fasting leptin level than CG and the difference was significant after adjustment for sex. To compare differences in insulin sensitivity between FDR and CG subjects the short insulin tolerance test (ITT), the homeostasis model assessment index (HOMA), and Quantitative Insulin sensitivity Check Index (QUICKI) were performed. Average ITT - derived insulin sensitivity as KITT values was significantly higher in CG than in FDR (26.47±8.41 vs. 23.81±7.39 mmol/l/min, p=0.029). Both HOMA index (3.27±2.49 vs. 2.25±1.58 mmol/mU/l, p=0.002) and QUICKI (0.335±0.034 vs. 0.354±0.044, p=0.001) were significantly different between FDR and CG reflecting a significant reduction in insulin sensitivity in the relatives group. Lean FDR (BMI less than 25.0) had significant higher fasting insulin, C-peptide and leptin concentrations than lean CG subjects. Also the lean relatives had significantly higher HOMA and QUICKI index scores than lean controls. Obese (BMI more than 25.0) FDR had higher fasting glucose, fasting insulin and leptin. Obese FDR were more insulin resistant by HOMA than obese CG subjects. In conclusion healthy glucose tolerant FDR were more insulin resistant, had increased fasting glucose, fasting insulin, and leptin concentrations.