title: DXA surrogates for visceral fat are inversely associated with bone density measures in adolescent athletes with menstrual dysfunction.
abstract: OBJECTIVE
  Lean mass is associated with bone mineral density (BMD) in athletes, attributable to the anabolic pull of muscle on bone. Fat mass is also important, and subcutaneous fat positively and visceral fat negatively correlates with BMD in obese adolescents. The contribution of regional body composition to low BMD in amenorrheic athletes (AA) has not been elucidated. We hypothesized that in adolescent athletes (runners), BMD is associated positively with total fat (surrogate for subcutaneous fat) and lean mass, and inversely with percent trunk fat and trunk-to-extremity fat ratio (surrogates for visceral fat).
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  We examined BMD and body composition using dual energy X-ray absorptiometry (DXA) in 21 AA and 19 eumenorrheic athletes (EA) (12-18 years) (runners). We report total hip and height-adjusted BMD [lumbar bone mineral apparent density (LBMAD) and whole body bone mineral content/height (WBBMC/Ht)].
  
  
  RESULTS
  AA had lower BMD than EA. Lean mass was less strongly associated with hip BMD in AA than EA; fat mass was positively associated with LBMAD in EA. Percent trunk fat and trunk-to-extremity fat ratio were inversely associated with lumbar and WB measures in AA. In a regression model, lean and fat mass were positively, and percent trunk fat and trunk-to-extremity fat ratio negatively associated with LBMAD and WBBMC/Ht for all athletes, even after controlling for serum estradiol.
  
  
  CONCLUSIONS
  DXA surrogates for visceral fat are inversely associated with bone density in athletes.
authors.affiliation: Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
authors.forename: Kathryn E
authors.initials: KE
authors.lastname: Ackerman
authors.forename: Brittany
authors.initials: B
authors.lastname: Davis
authors.forename: Leah
authors.initials: L
authors.lastname: Jacoby
authors.forename: Madhusmita
authors.initials: M
authors.lastname: Misra
mesh_terms: D015502:Absorptiometry, Photon; D050154:Adiposity; D000293:Adolescent; D041923:Adolescent Development; D000568:Amenorrhea / Q000503:physiopathology*; D056352:Athletes; D015415:Biomarkers; D001823:Body Composition; D001827:Body Height; D015519:Bone Density; D002648:Child; D002657:Child Development; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D053716:Female Athlete Triad Syndrome / Q000503:physiopathology; D006801:Humans; D050152:Intra-Abdominal Fat / Q000502:physiology*; D012420:Running; D050151:Subcutaneous Fat / Q000502:physiology
chemical_list: D015415:Biomarkers