title: Effects of Growth Hormone on Bone.
abstract: OBJECTIVE
  Describe the effects of growth hormone (GH) and insulin-like growth factor 1 (IGF-1) on the skeleton.
  
  
  RESULTS
  The GH and IGF-1 axis has pleiotropic effects on the skeleton throughout the lifespan by influencing bone formation and resorption. GH deficiency leads to decreased bone turnover, delayed statural growth in children, low bone mass, and increased fracture risk in adults. GH replacement improves adult stature in GH deficient children, increases bone mineral density (BMD) in adults, and helps to optimize peak bone acquisition in patients, during the transition from adolescence to adulthood, who have persistent GH deficiency. Observational studies suggest that GH replacement may mitigate the excessive fracture risk associated with GH deficiency. Acromegaly, a state of GH and IGF-1 excess, is associated with increased bone turnover and decreased BMD in the lumbar spine observed in some studies, particularly in patients with hypogonadism. In addition, patients with acromegaly appear to be at an increased risk of morphometric-vertebral fractures, especially in the presence of active disease or concurrent hypogonadism. GH therapy also has beneficial effects on statural growth in several conditions characterized by GH insensitivity, including chronic renal failure, Turner syndrome, Prader-Willi syndrome, postnatal growth delay in patients with intrauterine growth retardation who do not demonstrate catchup growth, idiopathic short stature, short stature homeobox-containing (SHOX) gene mutations, and Noonan syndrome.
  
  
  CONCLUSIONS
  GH and IGF-1 have important roles in skeletal physiology, and GH has an important therapeutic role in both GH deficiency and insensitivity states.
authors.affiliation: Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts, USA; Harvard Medical School, Boston, Massachusetts, USA. Electronic address: ntritos@mgh.harvard.edu.
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Tritos
authors.affiliation: Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts, USA; Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Anne
authors.initials: A
authors.lastname: Klibanski
mesh_terms: D000818:Animals; D015519:Bone Density; D001842:Bone and Bones / Q000502:physiology*; D005260:Female; D013006:Growth Hormone / Q000172:deficiency / Q000502:physiology*; D006801:Humans; D008297:Male; D051379:Mice
chemical_list: D013006:Growth Hormone
keywords: acromegaly; bone; growth hormone; growth hormone deficiency; hypopituitarism