Endocrine Abstracts

Objective
Measurement of insulin sensitivity has always been a key interest in the clinical investigation of Type 2 diabetes mellitus. Previous studies have shown good correlation between the Oral Glucose Insulin Sensitivity (OGIS) Model and the gold standard euglycaemic hyperinsulinaemic glucose clamp. This study is to describe OGIS as an index for insulin sensitivity derived from glucose-insulin model in a clinical setting.
Methods
468 non-diabetes patients and 224 Type 2 Diabetes Mellitus patients underwent a 3 hour oral glucose tolerance test with standard 75 grammes glucose load. Both the control and diabetes group are sub-divided further according to body mass index and age. Insulin sensitivity values are calculated according to the OGIS model.
Results
In the Lean Control Group (n=139; age above 40 years), the insulin sensitivity value derived from OGIS (S_i) is 418.9 (SEM=0.063). In the Obese Control Group (n=123; age above 40years) (S_i) is 346.0 (SEM=0.040); Lean Control Group Under 40 (n=123) ((S_i)= 448.2 (SEM=0.064), Obese Control Group Under 40 (n = 79) (S_i)= 368.1 (SEM=0.106); In Diabetes Group age under 40 (n=16) ((S_i)= 257.8 (SEM=0.482)); Lean Diabetes Group Above 40 (n=103) (S_i)= 262.3 (SEM=0.133); Obese Diabetes Group Above 40(n=55) (S_i)= 255.9 (SEM=0.069). Correlation co-efficient value compared against HOMA Model is negative 0.9, as HOMA measures Insulin Resistance.
Conclusion
OGIS is a useful method for calculating insulin sensitivity and may be applicable in the clinical setting. It is user friendly and requires only 3 blood samples for calculation. It correlates well with HOMA-IR.