Background: Glucose metabolism effects of vitamin D deficiency are debated. GH therapy is associated with increased insulin values and decreased insulin sensitivity.
Objective and hypotheses: To investigate vitamin D status in short children treated with GH- to investigate if the known effects of GH therapy on glucose metabolism are modulated by vitamin D supplementation.
Method: 41 children treated with GH for short stature where evaluated 6 months before and 6 months after receiving vitamin D 1000 UI/day (colecalciferolum). We analysed: 1. Vitamin D status; 2. Glucose homeostasis evaluated with: glucose, HbA1S, Insulin, HOMA index before starting vitamin D supplementation and 6 month after vitamin D administration.
Results: Vitamin D level was below 30 ng/ ml in all the patients and bellow 10 ng/ml in 15% of the patients. Vitamin D supplementation with 1000 UI for 6 months increased vitamin D levels over 30 ng/ ml in 56% of the patients and over 10 ng/ml in all the patients. Vitamin D administration had a demonstrable influence on insulin secretion and insulin sensitivity: in vitamin D<10 ng /ml patients insulin correlated positively with vitamin D concentration. In vitamin D >30 ng/ml patients insulin concentration and HOMA index had a decreasing tendency which could be understood as an effect of lowering GH therapy induced hyperinsulinemia and insulin insensitivity and there metabolic consequences. There was no significant influence of vitamin D supplementation for six months on growth parameters.
Conclusion: Conclusions: vitamin D evaluation and supplementation is needed in short patients on GH therapy for decreasing the glucose metabolism consequences of GH therapy and possibly in the long time for improving response to therapy.
01 - 03 Oct 2015
European Society for Paediatric Endocrinology