Insulin sensitivity in the initial phase of type 1 diabetes mellitus.

The blood glucose response to a brief infusion of insulin (0.012 U/kg body wt) was studied in the initial phase of Type 1 diabetes in 21 children and in 20 healthy controls. The insulin effect was impaired in most of the diabetics and the mean blood glucose decrement was 14.3 +/- 3.5% (SEM) as compared with 20.9 +/- 2.1% in the normals. Subgrouping the diabetics according to the severity of the diabetic condition revealed normal (or even supranormal) sensitivity in the diabetics with mild metabolic derangement (mean blood glucose decrement 36.2 +/- 6.0%). In children with more disturbed metabolism mean blood glucose decrement was only 5.6 +/- 0.8% indicating a marked insulin resistance. Further evidence for a relationship between the insulin sensitivity and the severity of the diabetic state was found in the correlation between the percentual blood glucose decrement and the fasting blood glucose (r = -0.79, p less than 0.01), the glucose assimilation rate (r = 0.71, p less than 0.01), as well as the blood glucose level at 120 min during the OGTT (r = -0.76, p less than 0.01). Four of the insulin-resistant patients were re-tested during remission and exhibited then normal insulin sensitivity.