IMPAIRED COUNTERREGULATORY HORMONE RESPONSES TO HYPOGLYCEMIA IN CHILDREN AND ADOLESCENTS WITH NEW-ONSET IDDM

Children with long-standing IDDM have impaired counterregulatory respo nses to hypoglycemia. To determine whether children with new onset IDD M also have altered counterregulation, we studied the counterregulator y responses to hypoglycemia in twenty children with new onset IDDM (5- 6 days, age 12.6 +/- 2.9 yr, mean +/- SD), and compared these response s to 47 subjects with long-standing IDDM (duration 7.8 +/- 3.6 yr, age 15.3 +/- 2.5 yr) and 21 controls (age 14.2 +/- 2.8 yr). Six new onset subjects were restudied three months later during their remission. Gl ucose nadir in new onset (2.7 +/- 0.1 mmol.l(-1)) was similar to contr ols (2.4 +/- 0.1 mmol.l(-1)), but was higher than in long-standing IDD M (2.2 +/- 0.1 mmol.l(-1)). Both groups of diabetic subjects had lower glucagon responses to hypoglycemia than controls (p<0.005). Glucagon responses in new and long-standing diabetes did not differ. Epinephrin e was diminished in new IDDM compared to controls (p<0.01). Glucose re covery was faster in new onset than in long-standing IDDM (p<0.001) an d the same as in controls. Responses remained diminished 3 months afte r diagnosis despite increased C-peptide and lower glycosylated hemoglo bin. Thus, children with IDDM have diminished counterregulatory respon ses to hypoglycemia at diagnosis, that are similar to those in longsta nding IDDM. The reasons for this impairment and its clinical applicati on in childhood require further investigation.