Study of the rate of early glucose disappearance following insulin injection: insulin sensitivity index.
The euglycaemic hyperinsulinaemic glucose clamp is usually considered as the reference technique to evaluate insulin sensitivity. As it is an expensive and time-consuming tool, we therefore tried to validate a simple insulin tolerance test (ITT) (IV bolus of 0.1 IU/kg of regular insulin, with glucose sampling at -5, 0, 3, 5, 7, 10 and 15 min) and to demonstrate its usefulness. Insulin sensitivity was measured by DG/G0 ratio (G0 = initial glycaemia, DG is the variation between G0 and the glycaemia obtained at 15 min by the calculation of the regression plot). We confirmed the existence of a correlation between the glucose uptake (mg/kg per min) evaluated by glucose clamp and the DG/G0 index (r = 0.9, P < 0.01). There was no stimulation of hormonal counter regulation during the test. The ITT was significantly correlated both with fasting insulin (r = -0.43, P < 0.01), and post-glucose load insulin concentration (r = -0.67, P < 0.01); each measurement expressing insulin sensitivity. Four groups of patients with different insulin sensitivity: controls, NIDDM, gynoid and android obese subjects, were clearly separated by ITT. We showed that fasting glycaemia and DG/G0 were correlated (y = 2.63/x - 0.093; r = 0.82, P < 0.01). These results suggest that ITT could be an easy, quick and low cost method to evaluate insulin resistance in clinical practice and epidemiological studies.
Grulet
H
H
Clinique médicale B, Hôpital Robert Debré, Reims, France.
Durlach
V
V
Hecart
A C
AC
Gross
A
A
Leutenegger
M
M
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood; D004837:Epinephrine / Q000097:blood; D005260:Female; D005934:Glucagon / Q000097:blood; D015309:Glucose Clamp Technique; D005951:Glucose Tolerance Test / Q000379:methods; D013006:Growth Hormone / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D006973:Hypertension / Q000097:blood; D007328:Insulin / Q000494:pharmacology*; D007333:Insulin Resistance; D008297:Male; D009638:Norepinephrine / Q000097:blood; D009765:Obesity / Q000097:blood; D011085:Polycystic Ovary Syndrome / Q000097:blood; D012016:Reference Values; D012737:Sex Factors
D001786:Blood Glucose; D007328:Insulin; D013006:Growth Hormone; D005934:Glucagon; D006854:Hydrocortisone; D009638:Norepinephrine; D004837:Epinephrine