Insulin sensitivity by oral glucose minimal models: validation against clamp

Area of Science:

• Metabolic physiology
• Endocrinology
• Clinical diagnostics

Background:

• Accurate measurement of insulin sensitivity is crucial for understanding metabolic diseases.
• Oral minimal models offer a non-invasive approach to assess insulin sensitivity (S(I)) and its effect on glucose disposal (S(I)*).
• Previous validation focused on meal tests; clamp validation was needed.

Purpose of the Study:

• To validate oral minimal model estimates of S(I) and S(I)* against the gold standard euglycemic hyperinsulinemic clamp.
• To assess the reliability of oral minimal models for estimating insulin sensitivity in diverse metabolic conditions.

Main Methods:

• 21 subjects underwent both a multiple-tracer oral glucose tolerance test (OGTT) and a labeled euglycemic hyperinsulinemic clamp.
• Oral minimal model parameters (S(I), S(I)*) were calculated from OGTT data.
• Correlation and agreement between oral model estimates and clamp-derived values were analyzed.

Main Results:

• Satisfactory correlations were found between oral minimal model S(I) and clamp estimates (r = 0.81, P < 0.001).
• Oral minimal model S(I)* also showed good correlation with clamp estimates (r = 0.71, P < 0.001).
• S(I) from the oral model was significantly lower than clamp estimates, while S(I)* values were similar.

Conclusions:

• The oral minimal model provides a reliable method for estimating insulin sensitivity (S(I)) and glucose disposal (S(I)*).
• These findings support the use of oral minimal models as a practical tool in large-scale clinical trials for metabolic research.
• The validated oral method enhances the assessment of insulin resistance non-invasively.