Insulin sensitivity relates to other cardiovascular risk factors in young men: validation of some modifications of the hyperinsulinaemic, isoglycaemic glucose clamp technique.
Reduced peripheral sensitivity to insulin-stimulated glucose disposal, insulin resistance, is considered to be central in the metabolic cardiovascular syndrome. The hyperinsulinaemic euglycaemic glucose clamp technique was introduced by DeFronzo in 1979 and is regarded as the reference method for quantifying insulin resistance in skeletal muscle tissue. Recently, we used this technique in young men to relate insulin resistance (inverse of insulin sensitivity) to a number of established cardiovascular risk factors. The method has undergone numerous modifications since 1979 which have not been extensively validated. Therefore, we now describe the modified hyperinsulinaemic, isoglycaemic glucose clamp procedure performed in our laboratory and validate some of the modifications. Five young/middle-aged men were examined twice in three weeks and then re-examined after 4 years in the same way. The intrasubject day-to-day variability in insulin sensitivity was 5%. The average reduction in insulin sensitivity after 4 years was 21%. The last 60 min of the clamp offered a better basis for calculating glucose disposal rate (GDR) than the last 20 min. The variation in glucose measurements during clamp was 5%. We thus found that our modified isoglycaemic hyperinsulinaemic glucose clamp technique for assessing insulin sensitivity in skeletal muscle tissue is accurate and reproducible when performed in young/middle-aged men.
Fossum
E
E
Department of Internal Medicine, Ullevaal Hospital, University of Oslo, Norway.
Høieggen
A
A
Moan
A
A
Nordby
G
G
Kjeldsen
S E
SE
D000328:Adult; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000473:pathology / Q000503:physiopathology*; D005947:Glucose / Q000378:metabolism; D015309:Glucose Clamp Technique; D006801:Humans; D006946:Hyperinsulinism / Q000503:physiopathology; D007003:Hypoglycemia / Q000503:physiopathology; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D015203:Reproducibility of Results; D012307:Risk Factors
D005947:Glucose