Pubertal stage and hypoglycaemia counterregulation in type 1 diabetes.
OBJECTIVE
To compare physiological and autonomic responses to acute hypoglycaemia in diabetic children in pre-, mid-, and post-pubertal stages of development.


METHODS
Twenty seven children (8 pre-pubertal, 7 mid-pubertal, 12 post-pubertal) with type 1 diabetes were studied. Hypoglycaemia was induced by insulin infusion until an autonomic reaction (R) was identified. Counterregulatory hormone levels were measured at baseline, R, R+15, and R+30 minutes. Haemodynamic changes and sweat production were measured.


RESULTS
The mean blood glucose level at R was lower in pre-pubertal than mid-pubertal children (2.0 v 2.5 mmol/l), and was positively correlated with HbA1c. Glucagon and noradrenaline responses to hypoglycaemia were minimal in all children. A brisk increase in pancreatic polypeptide (PP) concentration only occurred in post-pubertal children. Only two children showed a sweating response to hypoglycaemia.


CONCLUSIONS
The blood glucose level at which sympatho-adrenal responses to hypoglycaemia were activated was associated with glycaemic control, and varied with pubertal stage. As in adults, the glucagon response to hypoglycaemia was deficient within a few years of developing diabetes. However, sweating and secretion of PP in response to hypoglycaemia did not occur until after puberty, indicating some qualitative differences from adults.
Ross
L A
LA
Section of Child Life and Health, Department of Reproductive and Developmental Sciences, University of Edinburgh, Scotland, UK.
Warren
R E
RE
Kelnar
C J H
CJ
Frier
B M
BM
D000293:Adolescent; D000704:Analysis of Variance; D001341:Autonomic Nervous System / Q000503:physiopathology; D001786:Blood Glucose / Q000032:analysis; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000503:physiopathology*; D004837:Epinephrine / Q000097:blood; D005260:Female; D005934:Glucagon / Q000097:blood; D019382:Human Growth Hormone / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007003:Hypoglycemia / Q000097:blood / Q000503:physiopathology*; D007004:Hypoglycemic Agents / Q000008:administration & dosage; D007328:Insulin / Q000008:administration & dosage; D008297:Male; D009638:Norepinephrine / Q000097:blood; D010191:Pancreatic Polypeptide / Q000097:blood; D011627:Puberty / Q000502:physiology*; D013546:Sweating / Q000502:physiology
D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin; D019382:Human Growth Hormone; D010191:Pancreatic Polypeptide; D005934:Glucagon; D006854:Hydrocortisone; D009638:Norepinephrine; D004837:Epinephrine