Growth hormone treatment of children with short stature increases insulin secretion but does not impair glucose disposal

Pediatricians willing to administer GH to non-GH-deficient children with short stature are concerned about the potential adverse effects of this hormone on glucose homeostasis and insulin action. This study was designed to determine the effects of GH therapy on carbohydrate metabolism in 10 prepubertal non-GH-deficient children with short stature. After 12 months of treatment with 0.3 U GH/kg BW.day, which resulted in an increase in height velocity from 4.0 +/- 0.3 (+/- SE) to 11.0 +/- 0.4 cm/yr, glucose tolerance was not impaired in these children. Not only were their fasting and postprandial plasma glucose concentrations unchanged from the pretreatment values, but basal glucose turnover did not vary; it was 0.53 +/- 0.04 before and 0.64 +/- 0.06 mmol/m2.min after GH treatment. Using the euglycemic clamp technique, the dose-response curves describing the effects of insulin on glucose disposal were comparable before and after GH treatment. There was a consistent 1.5- to 2-fold increase in plasma insulin and C-peptide concentrations during GH treatment, in both the basal and postprandial states, and after oral glucose or iv glucagon stimulation. We conclude that the GH regimen employed was remarkably effective in increasing growth velocity and devoid of detectable diabetogenic effects during a 1-yr treatment period in these non-GH-deficient children. (glucose, 1 mmol/L = 18 mg/dL; insulin, 1 pmol/L = 0.139 microU/mL; C-peptide, 1 pmol/L = 0.003 ng/ml).