Muscle and Liver Insulin Resistance Indexes Derived From the Oral Glucose Tolerance Test

• Published in: Diabetes care Vol. 30; no. 1; pp. 89 - 94
• Main Authors: Abdul-Ghani, Muhammad A, Matsuda, Masafumi, Balas, Bogdan, DeFronzo, Ralph A
• Format: Journal Article
• Language: English
• Published: Alexandria, VA American Diabetes Association 2007
• Subjects: Adolescent; Adult; Aged; Biological and medical sciences; blood; blood glucose; body mass index; Cardiovascular disease; Diabetes; Diabetes. Impaired glucose tolerance; Diagnosis; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; fasting; Glucose; Glucose Intolerance; Glucose Intolerance - physiopathology; glucose tolerance; Glucose Tolerance Test; Glucose tolerance tests; Glycemic index; Health aspects; Hispanic Americans; Hispanic or Latino; Humans; Hyperglycemia; Insulin; Insulin - blood; Insulin resistance; Insulin Resistance - physiology; liver; Liver - physiology; Liver - physiopathology; Measurement; Medical sciences; Mexican Americans; Middle Aged; Muscle, Skeletal; Muscle, Skeletal - physiology; Muscle, Skeletal - physiopathology; physiology; physiopathology; Reference Values; tritium; United States; Endocrinopathy; Human; Pancreatic hormone; Digestive system; Liver; Oral administration; Exploration; Glucose tolerance test; Index; Insulin; Target tissue resistance; Insulin resistance; Muscle
• ISSN: 0149-5992; 1935-5548
• DOI: 10.2337/dc06-1519

OBJECTIVE:--To derive indexes for muscle and hepatic insulin sensitivity from the measurement of plasma glucose and insulin concentrations during an oral glucose tolerance test (OGTT). RESEARCH DESIGN AND METHODS--A total of 155 subjects of Mexican-American origin (58 male and 97 female, aged 18-70 years, BMI 20-65 kg/m²) with normal glucose tolerance (n = 100) or impaired glucose tolerance (n = 55) were studied. Each subject received a 75-g OGTT and a euglycemic insulin clamp in combination with tritiated glucose. The OGTT-derived indexes of muscle and hepatic insulin sensitivity were compared with hepatic and muscle insulin sensitivity, which was directly measured with the insulin clamp, by correlation analysis. RESULTS:--The product of total area under curve (AUC) for glucose and insulin during the first 30 min of the OGTT (glucose₀₋₃₀[AUC] x insulin₀₋₃₀[AUC]) strongly correlated with the hepatic insulin resistance index (fasting plasma insulin x basal endogenous glucose production) (r = 0.64, P < 0.0001). The rate of decay of plasma glucose concentration from its peak value to its nadir during the OGTT divided by the mean plasma insulin concentration (dG/dt [divide sign] I) strongly correlated with muscle insulin sensitivity measured with the insulin clamp (P = 0.78, P < 0.0001). CONCLUSIONS:--Novel estimates for hepatic and muscle insulin resistance from OGTT data are presented for quantitation of insulin sensitivity in nondiabetic subjects.