title: Bone metabolism markers in adolescent girls with eating disorders and weight loss: effects of growth, weight trend, developmental and menstrual status.
abstract: Serum concentrations of osteocalcin (OC) decrease and those of C-terminal telopeptide of type 1 collagen (CTX) increase during weight loss in adolescent girls with eating disorders (ED). The impact of weight loss on bone metabolism markers is greatest in premenarcheal girls.
  
  
  BACKGROUND
  Adolescents with ED stand a risk of not reaching optimal peak bone mass and develop osteoporosis. Previous investigations are contradictory as to how markers of bone formation and resorption change during weight loss and nutritional rehabilitation.
  
  
  METHODS
  Serum OC and CTX were measured at assessment of 461 adolescent girls with ED and during treatment of 55 girls with anorexia nervosa. Bone metabolism was related to weight, weight change and growth rate.
  
  
  RESULTS
  At assessment, OC concentrations were positively correlated with growth rate and inversely with age and (rate of) weight loss. Growth rate was the only predictor of CTX concentrations in premenarcheal girls. In postmenarcheal girls, CTX concentrations were inversely correlated with age and rate of weight loss. During weight gain, there was an increase of OC concentrations. CTX concentrations decreased at the onset of weight gain and increased when near normal weight was reached.
  
  
  CONCLUSIONS
  Bone formation markers decrease and resorption markers increase during weight loss. The effects are independent of menstrual status but the impact on bone formation markers is greater in young, premenarcheal girls. Markers are normalised during weight gain but it is conceivable that repeated and/or prolonged weight loss in adolescents reduces peak bone mass.
authors.affiliation: Department of Women's and Children's Health, Uppsala University, Uppsala, Sweden. ingemar.swenne@akademiska.se
authors.forename: I
authors.initials: I
authors.lastname: Swenne
authors.forename: M
authors.initials: M
authors.lastname: Stridsberg
mesh_terms: D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D001835:Body Weight / Q000502:physiology*; D001846:Bone Development / Q000502:physiology; D001851:Bone Diseases, Metabolic / Q000175:diagnosis* / Q000378:metabolism*; D001842:Bone and Bones / Q000378:metabolism; D024042:Collagen Type I / Q000097:blood; D001068:Feeding and Eating Disorders / Q000378:metabolism*; D005260:Female; D006801:Humans; D008572:Menarche / Q000502:physiology; D008598:Menstruation / Q000502:physiology*; D015675:Osteocalcin / Q000097:blood; D010024:Osteoporosis / Q000175:diagnosis / Q000378:metabolism; D010455:Peptides / Q000097:blood; D011627:Puberty / Q000502:physiology*
chemical_list: D015415:Biomarkers; D024042:Collagen Type I; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D015675:Osteocalcin