[Effect of glipizide on glycemic control and peripheral insulin sensitivity in type 1 diabetics]

To assess the effect of Glipizide on glycaemic control and peripheral insulin sensitivity, 9 type 1 (insulin dependent) diabetic patients with normal BMI, mean age 42.1 +/- 11.0 years, diabetes duration 16.3 +/- 9.2 years were studied. They were treated by continuous subcutaneous insulin infusion for a mean duration of 32.2 +/- 11.0 months, they were in good glycaemic control (mean HbA1 7.9 +/- 1.2%, upper limit of normal value 7.5%). In a double blind randomized control study they were successively allocated for a three month period to 15 mg of Glipizide daily or a Placebo. At the end of each period the following parameters were recorded: HbA1, mean plasma glucose levels, daily insulin dosage: basal rate and pre prandial bolus, peripheral insulin sensitivity assessed by euglycaemic hyperinsulinic clamp technique, the addition of Glipizide did not induce any statistically significant modification of HbA1, glycaemic values, and daily insulin dosage: basal rate 18.2 +/- 8.7 vs. 17.9 +/- 7.3 IU/24 hours and pre prandial bolus 18.6 +/- 7.0 vs 17.6 +/- 6.3 IU/24 hours. During the glucose clamp, glucose uptake was similar under Glipizide or Placebo with the 3 levels of insulin infused. These results suggest that in type 1 diabetic patients the addition of Glipizide to insulin therapy does not alter glycaemic control and peripheral insulin sensitivity.