title: Bone turnover, bone mineral density, and fracture risk in acromegaly: a meta-analysis.
abstract: BACKGROUND
  GH excess causes an increase in bone turnover, but the consequences in terms of skeletal fragility have long been uncertain due to the heterogeneity of studies dealing with this topic.
  
  
  OBJECTIVE
  We conducted a meta-analysis of studies examining the effects of acromegaly on bone turnover, bone mineral density (BMD), and fractures. Furthermore, we evaluated the effects of sex, gonadal status, and activity of disease on skeletal end-points in acromegaly.
  
  
  METHODS
  We conducted MEDLINE and EMBASE systematic searches up to December 31, 2013.
  
  
  METHODS
  Studies conducted in patients with acromegaly and reporting at least one determinant of skeletal fragility.
  
  
  METHODS
  Study design, patient characteristics, interventions, and outcomes were independently extracted by two authors. We calculated the standardized mean difference (SMD) of bone turnover and BMD differences, whereas fractures were presented as relative frequencies in acromegaly and odds ratios between patients and controls.
  
  
  RESULTS
  Forty-one studies fulfilled eligibility criteria and were therefore selected for data extraction and analysis. A total of 1935 patients were included (eight to 206 per study). Acromegaly patients had higher bone formation (SMD, 1.49; 95% confidence interval [CI], 0.97-2.01; P < .0001) and bone resorption (SMD, 1.57; 95% CI, 1.03-2.10; P < .0001) as compared to control subjects, without significant differences in lumbar spine BMD. BMD at the femoral neck tended to be higher in acromegaly patients vs control subjects (SMD, 0.67; 95% CI, 0.07-1.27; P = .03). Patients with acromegaly had high frequency of vertebral fractures (odds ratio, 8.26; 95% CI, 2.91-23.39; P < .0001), in close relationship with male gender, hypogonadism, and active acromegaly.
  
  
  CONCLUSIONS
  LIMITATIONS included heterogeneous study protocols with possible variability in the assessment of skeletal end-points.
  
  
  CONCLUSIONS
  Skeletal fragility is an emerging complication of acromegaly.
authors.affiliation: Endocrinology (G.M., F.M., V.S., A.G.) and Radiology (R.M.), University of Brescia, 25123 Brescia, Italy; Department of Oncology (E.B., I.F.), Instituto di Ricovero e Cura a Carattere Scientifico-Istituto di Ricerche Farmacologiche "Mario Negri", 20156 Milan, Italy; and Novartis Farma (M.S.), 21040 Origgio, Italy.
authors.forename: Gherardo
authors.initials: G
authors.lastname: Mazziotti
authors.forename: Elena
authors.initials: E
authors.lastname: Biagioli
authors.forename: Filippo
authors.initials: F
authors.lastname: Maffezzoni
authors.forename: Maurizio
authors.initials: M
authors.lastname: Spinello
authors.forename: Vincenza
authors.initials: V
authors.lastname: Serra
authors.forename: Roberto
authors.initials: R
authors.lastname: Maroldi
authors.forename: Irene
authors.initials: I
authors.lastname: Floriani
authors.forename: Andrea
authors.initials: A
authors.lastname: Giustina
mesh_terms: D000172:Acromegaly / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology; D015519:Bone Density / Q000502:physiology*; D016723:Bone Remodeling / Q000502:physiology*; D005272:Femur Neck / Q000000981:diagnostic imaging; D050723:Fractures, Bone / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging; D011859:Radiography; D012306:Risk