J Korean Diabetes Assoc.  1997 Dec;21(4):425-431.

Measurement of Insulin Sensitivity Index Estimated from LDIGIT ( Continuous Low Dose Insulin and Glucose Infusion Test

• Song YD
• Cha BS
• Park SW
• Won YJ
• Nam SY
• Lim SK
• Kim KR
• Lee HC
• Huh KB

Abstract

BACKGROUND: Measurement of insulin sensitivity index by continuous low dose insulin and glucose infusion test(LDIGIT) has been reported to be simple and reliable.
METHODS
The method is a refinement of the modified Harano test and consisted of continuous low dose insulin(25mU/kghr) and glucose(4mg/kghr) infusion lasting 150 min. Insulin sensitivity was evaluated as the amount of glucose infusion divided by the steady state serum insulin and glucose levels achieved at the end of the test. Insulin secretion was expressed as the incremental area for C-peptide concentration during the first 15 min of the test. The indices of insulin sensitivity and insulin secretion yielded by LDIGIT were compared with those derived from the euglycemic clamp and oral glucose tolerance test (OGTT), respectively. Thirteen subjects underwent LDIGIT and euglycemic clamp.
RESULTS
LDIGIT resulted in stable final glucose levels but 3 subjects showed hypoglycemia during the test. The index of insulin secretion provided by LBIGIT did not correlate well with that of OGTT. There was a significant correlation between the ISI (insulin sensitivity index) determined by LDIGIT and the ISI determined by clamp(r=0.60, p<0.05).
CONCLUSION
LDIGIT is a simple and accurate methcd to assess insulin sensitivity. It can be used in population studies and in situations when more complex technique is not feasible. However, it is desirable to reduce the insulin infusion rate to avoid the occurrence of hypoglycemia in Koreans.

Keyword

Insulin sensitivity; Low dose insulin and glucose infusion

MeSH Terms

C-Peptide
Glucose Clamp Technique
Glucose Tolerance Test
Glucose*
Hypoglycemia
Insulin Resistance*
Insulin*
C-Peptide
Glucose
Insulin