Growth Hormone Deficiency During the Transition Phase

Abstract

The growth hormone (GH)-insulin-like growth factor-1 (IGF-1) axis has several roles. While achievement of a satisfactory height is probably the most important and well-known, it is now clear that it also affects body composition, metabolism, muscle mass and bone density during the transition period. Recombinant-growth hormone (Rec-GH) therapy is normally administered to GH-deficient children to achieve a reasonable final height. Retesting with a provocative test (insulin tolerance test or growth-hormone-releasing hormone + arginine test) is necessary during the transition period, after measuring IGF-1 levels. If the patient is still GH-deficient, rec-GH therapy should be restarted at 0.2–0.5 mg/day up to a final dosage of 0.8–1.0 mg/day (albeit there is no general consensus on the dosage). In fact, there is widespread literature evidence of the negative impact of GH-deficiency during the transition period, which provokes increased visceral fat and waist/hip ratio, decreased muscle mass and bone density and increased cardiovascular morbidity and mortality.