Glucose metabolism in children with GH deficiency before and after GH therapy
L. De Martino, D. Capalbo, R. Di Mase, A. Esposito, M. Rezzuto, F. Barbieri & M. Salerno
Background: Adults with untreated GH deficiency (GHD) may have a cluster of cardiovascular risk factors. The effects of GH replacement therapy on insulin homeostasis in GHD subjects are still debated. Only a few studies investigated the effects of GHD and GH therapy on glucose metabolism in children.
Objective: To evaluate the effects of GHD and GH treatment on glucose metabolism in a large cohort of GHD children before and after GH replacement therapy.
Subjects and methods: Fasting glucose, insulin, HbA1c, and HOMA were assessed in 60 GHD children, aged 9.8±0.3 years, before and after 1, 2 and 4 years of GH therapy. 60 healthy, age-, sex- and BMI-matched healthy controls were enrolled.
Results: In GHD children at baseline, fasting glucose (77.8±1 vs 77.9±1.2 mg/dl), insulin (4.7±0.4 vs 4.6±0.4 μU/ml), HOMA (1.26±0.2 vs 1.12±0.1) and HbA1c (5.29±0.1 vs 5.29±0.04%) levels were comparable to healthy controls. One year of GH therapy (33 μg/kg per day) was associated with significant increase in insulin (7.69±0.6, P<0.0001) and HOMA (1.64±0.15, P=0.009), without significant changes in fasting glucose and HbA1c levels. Insulin and HOMA levels did not further increase after 2 (7.56±0.6 and 1.85±0.2 respectively) and 4 years (7.65±0.7 and 1.5±0.1 respectively) of treatment, remaining significantly elevated compared to pre-treatment levels. Fasting glucose and HbA1c did not change after 2 and 4 years of GH therapy.
Conclusions: Untreated GHD was not associated with significant alterations of insulin homeostasis. One year of GH treatment was associated with a slight impairment in insulin sensitivity without further change during long-term GH therapy.
Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.
Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.