title: The impact of glucocorticoid replacement on bone mineral density in patients with hypopituitarism before and after 2 years of growth hormone replacement therapy.
abstract: BACKGROUND
  Patients with hypopituitarism have reduced bone mineral density (BMD) and increased fracture risk.
  
  
  OBJECTIVE
  The aim of this study was to analyze the effects of glucocorticoid (GC) replacement on BMD before and after 2 years of GH therapy in hypopituitary patients. The main hypothesis was that patients on GC replacement demonstrate greater improvement in BMD when treated with GH.
  
  
  METHODS
  This was a post hoc analysis of data from a prospective single-center study.
  
  
  METHODS
  Data on 175 adult patients with hypopituitarism and verified GH deficiency due to nonfunctioning pituitary adenoma were analyzed. Ninety-eight (56%) were GC insufficient, receiving a mean ± SD hydrocortisone equivalent dose of 20.9 ± 5.0 mg/d.
  
  
  METHODS
  BMD before and after 2 years of GH replacement therapy was measured by using dual-energy X-ray absorptiometry.
  
  
  RESULTS
  BMD at baseline did not differ between GC-sufficient and -insufficient patients, neither at lumbar spine nor femur neck. After 2 years on GH replacement, BMD increased in both groups. After adjustment for weight, age, gender, free T4 concentrations, change in IGF-I levels, and sex hormone treatment, GC sufficiency was associated with a greater increase in BMD at the femur neck (ΔT-score in GC insufficient patients 0.09 ± 0.46, in GC sufficient patients 0.19 ± 0.43; P < .05) but not at the lumbar spine.
  
  
  CONCLUSIONS
  GH replacement therapy for 2 years increased BMD in hypopituitary patients. In contrast to our hypothesis, GC-insufficient patients receiving near physiological doses of hydrocortisone do not show a greater therapeutic response to GH therapy than their GC-sufficient counterparts.
authors.affiliation: Faculty of Medicine (H.R.A.), University of Iceland, 101 Reykjavik Iceland; and Institute of Medicine (G.J., O.R.), Sahlgrenska Academy, University of Gothenburg, SE-413 45 Göteborg Sweden.
authors.forename: Hjalmar
authors.initials: H
authors.lastname: Ragnar Agnarsson
authors.forename: Gudmundur
authors.initials: G
authors.lastname: Johannsson
authors.forename: Oskar
authors.initials: O
authors.lastname: Ragnarsson
mesh_terms: D000236:Adenoma / Q000150:complications / Q000188:drug therapy; D000328:Adult; D000368:Aged; D015519:Bone Density / Q000187:drug effects*; D005260:Female; D005938:Glucocorticoids / Q000627:therapeutic use*; D020249:Hormone Replacement Therapy; D019382:Human Growth Hormone / Q000627:therapeutic use*; D006801:Humans; D007018:Hypopituitarism / Q000188:drug therapy* / Q000209:etiology; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000150:complications / Q000188:drug therapy; D012189:Retrospective Studies
chemical_list: D005938:Glucocorticoids; D019382:Human Growth Hormone