title: Changes in bone mineral density and body composition during initial and long-term gonadotropin-releasing hormone agonist treatment for prostate carcinoma.
abstract: BACKGROUND
  Initial treatment with a gonadotropin-releasing hormone (GnRH) agonist increases fat mass, decreases lean body mass, and decreases bone mineral density (BMD) in men with prostate carcinoma. To the authors' knowledge, little is known regarding either the long-term effects of treatment or predictors of treatment-related changes in BMD and body composition.
  
  
  METHODS
  The authors analyzed prospective 12-month data from 65 men during initial and long-term GnRH agonist treatment for prostate carcinoma. Relationships between baseline characteristics (age, treatment duration, body mass index, and baseline values for outcome of interest) and changes in lean mass, fat mass, and BMD were assessed using univariate and multivariate regression models.
  
  
  RESULTS
  Mean BMD of total hip decreased by 1.9 +/- 2.7%, lean body mass decreased by 2.0 +/- 3.3%, and fat mass increased by 6.6 +/- 9.4% at 12 months (P < 0.001 for each comparison). Twenty-three men (35%) had received treatment with a GnRH agonist before study entry, and the mean (+/- standard deviation) duration of previous treatment was 35 +/- 41 months. Longer duration of previous GnRH agonist treatment was found to independently predict less fat accumulation and less loss of lean body mass in multivariate models. In contrast, the duration of GnRH agonist treatment did not significantly predict changes in BMD. Other covariates did not appear to predict changes in body composition or BMD consistently.
  
  
  CONCLUSIONS
  The results of the current study showed that fat mass increased and lean body mass decreased mostly during initial GnRH agonist therapy whereas BMD decreased steadily during initial and long-term treatment.
authors.affiliation: Biostatistics Center, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
authors.forename: Hang
authors.initials: H
authors.lastname: Lee
authors.forename: Katelyn
authors.initials: K
authors.lastname: McGovern
authors.forename: Joel S
authors.initials: JS
authors.lastname: Finkelstein
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Smith
mesh_terms: D000368:Aged; D001823:Body Composition; D015519:Bone Density; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists*; D006801:Humans; D008297:Male; D010024:Osteoporosis / Q000139:chemically induced; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D013997:Time Factors
chemical_list: D007987:Gonadotropin-Releasing Hormone