Glucose counterregulation in type 1 diabetic patients with decreased symptoms of hypoglycemia after insulin pump treatment.

We were interested in studying whether impaired hypoglycemic awareness after intensified insulin treatment with insulin pumps is associated with impaired glucose counterregulation. Glucose counterregulatory hormones were measured in 7 type I diabetic patients with altered symptoms after 6 months of continuous subcutaneous insulin infusion (CSII) (group 1) and in 9 patients with unchanged symptoms of hypoglycemia under CSII (group 2). The groups did not differ in diabetic control, duration of diabetes, or prevalence of neuropathy. Counterregulatory hormone response to an insulin-induced episode of hypoglycemia was measured before (first test) and after 6 months (second test) of CSII. Glucose nadirs and glucose recovery were similar in both groups and both tests. The mean plasma glucagon values demonstrate a lack of glucagon response in both groups and both tests. Growth hormone and cortisol increased in both groups and both tests without any difference between the groups or first and second tests. Epinephrine response was similar in both tests of group 2 (first test: 50 +/- 5 to 416 +/- 73; second test; 45 +/- 5 to 456 pg/ml), while in group 1 the response was not increased significantly in the second test [first test: 32 +/- 6 to 346 +/- 63; second test: 44 +/- 7 to 575 +/- 91 pg/ml; areas under curve (AUC) 11,977 and 16,345 pg x ml-1 x 90 min-1 (p = 0.36)].(ABSTRACT TRUNCATED AT 250 WORDS)