Measurement of muscle insulin sensitivity in obese men.

AIMS: In 2007, a novel estimate of skeletal muscle insulin sensitivity was derived from the oral glucose tolerance test (OGTT). The aim of this investigation is to assess whether and to what extent the proposed index of skeletal muscle insulin sensitivity derived from the OGTT was associated with muscle insulin sensitivity measured using the hyperinsulinemic-euglycaemic clamp technique.

METHODS

Forty-six middle-aged, abdominally obese men (age 44 ± 8 years, waist circumference 107.4 ± 6.2) were studied. Each participant participated in a 2-hour, 75-g OGTT and a 3-hour hyperinsulinemic-euglycaemic clamp protocol.

RESULTS

The OGTT-derived index of muscle insulin sensitivity correlated with muscle insulin sensitivity measured with the insulin clamp (r=0.55, P<0.01), however, the standard error of estimate (SEE) when predicting muscle insulin sensitivity by the OGTT-derived index was 5.3 (50%).

CONCLUSION

Our findings suggest that despite a statistically significant association between the two methods, the OGTT approach lacks precision and is not a useful method for estimating skeletal muscle insulin sensitivity in abdominally obese men.