Visceral adipose tissue as an indicator of insulin resistance in nonobese patients with new onset type 2 diabetes mellitus

Background: Obesity and type 2 diabetes mellitus are characterized by insulin resistance. We determined the relationship between insulin resistance and visceral adipose tissue (VAT) and their correlation with bioimpedance analysis in nonobese new onset type 2 diabetes patients. Methods: A number of 30 new onset type 2 diabetes patients and 20 healthy control subjects with similar features, age between 45-72 years old, BMI < 27 kg/m(2), C-peptide > 0.6 nmol/L, were included in study. Fasting blood glucose, HbA1c, serum lipids, BMI, insulin, C-peptide, HOMA-IR, bioimpedance analysis and visceral and subcutaneous adipose tissue (by computed tomography) were measured. Results: In the patient group, VAT was significantly higher compared to healthy control group (33.17 +/- 10.23% vs. 16.53 +/- 7.85%, p < 0.001). In the patient group VAT was correlated with HOMA-IR (r = 0.62, p = 0.003), but no significant correlation was observed between VAT and bioimpedance analysis. Conclusions: The amount of VAT is significantly higher in nonobese new onset patients with type 2 diabetes than the healthy control group. In these patients, VAT measured by CT is an important indicator of insulin resistance. Although bioimpedance analysis can give an idea about total body fat and obesity, it is not sufficient in evaluating fat distribution and therefore is not effective in predicting insulin resistance.