Relationship Between Hypertriglyceridemic Waist Phenotype and Disposition Index in Chinese Men With Normal Glucose Tolerance

The relationship between hypertriglyceridemic waist (HTGW) phenotype, insulin sensitivity, and pancreatic β-cell function remains still unclear in subjects with normal glucose tolerance (NGT). The objective is to detect whether the disposition index (DI) could be used as a predictive indicator of insulin sensitivity and pancreatic β-cell function in men with HTGW phenotype and NGT. A total of 180 men without diabetes were recruited in this study and underwent an oral glucose tolerance test (OGTT) to calculate DI based on the OGTT. Subjects were put into Group A (normal waist circumference [WC] and triglyceride [TG] concentrations), B (enlarged WC or elevated TG concentrations), and C (HTGW phenotype, both enlarged WC and elevated TG concentrations) (n = 60 for each group) according to WC and TG concentrations. The OGTT plasma glucose concentrations at 0.5 and 1 hr for patients in Groups B and C were higher than those in Group A (both p < .05). Group C patients had significantly lower 1/[fasting insulin] values and DI than those in Group A (p < .05), and the 1/[fasting insulin] values in Group C were significantly lower than those in Group B (p < .05). DI correlated positively with high-density lipoprotein cholesterol (p < .05), which was independently associated with WC (p = .002) and TG (p = .009). The HTGW phenotype is associated with decreased DI among men with NGT, indicating decreased DI is a strong predictor of future impaired glucose tolerance, which can provide guidance and reference for screening patients with potential impaired glucose tolerance in Chinese community population.