title: Comparison of hip geometry, strength, and estimated fracture risk in women with anorexia nervosa and overweight/obese women.
abstract: BACKGROUND
  Data suggest that anorexia nervosa (AN) and obesity are complicated by elevated fracture risk, but skeletal site-specific data are lacking. Traditional bone mineral density (BMD) measurements are unsatisfactory at both weight extremes. Hip structural analysis (HSA) uses dual-energy X-ray absorptiometry data to estimate hip geometry and femoral strength. Factor of risk (φ) is the ratio of force applied to the hip from a fall with respect to femoral strength; higher values indicate higher hip fracture risk.
  
  
  OBJECTIVE
  The objective of the study was to investigate hip fracture risk in AN and overweight/obese women.
  
  
  METHODS
  This was a cross-sectional study.
  
  
  METHODS
  The study was conducted at a Clinical Research Center.
  
  
  METHODS
  PATIENTS included 368 women (aged 19-45 y): 246 AN, 53 overweight/obese, and 69 lean controls.
  
  
  METHODS
  HSA-derived femoral geometry, peak factor of risk for hip fracture, and factor of risk for hip fracture attenuated by trochanteric soft tissue (φ(attenuated)) were measured.
  
  
  RESULTS
  Most HSA-derived parameters were impaired in AN and superior in obese/overweight women vs controls at the narrow neck, intertrochanteric, and femoral shaft (P ≤ .03). The φ(attenuated) was highest in AN and lowest in overweight/obese women (P < .0001). Lean mass was associated with superior, and duration of amenorrhea with inferior, HSA-derived parameters and φ(attenuated) (P < .05). Mean φ(attenuated) (P = .036), but not femoral neck BMD or HSA-estimated geometry, was impaired in women who had experienced fragility fractures.
  
  
  CONCLUSIONS
  Femoral geometry by HSA, hip BMD, and factor of risk for hip fracture attenuated by soft tissue are impaired in AN and superior in obesity, suggesting higher and lower hip fracture risk, respectively. Only attenuated factor of risk was associated with fragility fracture prevalence, suggesting that variability in soft tissue padding may help explain site-specific fracture risk not captured by BMD.
authors: Neuroendocrine Unit (K.N.B., P.K.F., E.A.L., A.K., K.K.M.), Departments of Psychiatry (K.E.) and Radiology (M.A.B.), Massachusetts General Hospital and Harvard Medical School, and Neuroendocrine Unit (B.M.R., A.D.R., E.M., A.V.G.), Clinical Research Center (T.H.), Massachusetts General Hospital, and Division of Adolescent Medicine (M.G.), Massachusetts General Hospital for Children and Harvard Medical School, Boston, Massachusetts 02114; Klarman Center (T.W.), McLean Hospital and Harvard Medical School, Belmont, Massachusetts 02478; Cambridge Eating Disorders Center (S.E.), Cambridge, Massachusetts 02138; Wilkins Center for Eating Disorders (D.M.), Greenwich, Connecticut 06831; and Beth Israel Deaconess Medical Center (S.G.) and Harvard Medical School, Boston, Massachusetts 02446.
authors: Katherine Neubecker
authors: KN
authors: Bachmann
authors: Pouneh K
authors: PK
authors: Fazeli
authors: Elizabeth A
authors: EA
authors: Lawson
authors: Brian M
authors: BM
authors: Russell
authors: Ariana D
authors: AD
authors: Riccio
authors: Erinne
authors: E
authors: Meenaghan
authors: Anu V
authors: AV
authors: Gerweck
authors: Kamryn
authors: K
authors: Eddy
authors: Tara
authors: T
authors: Holmes
authors: Mark
authors: M
authors: Goldstein
authors: Thomas
authors: T
authors: Weigel
authors: Seda
authors: S
authors: Ebrahimi
authors: Diane
authors: D
authors: Mickley
authors: Suzanne
authors: S
authors: Gleysteen
authors: Miriam A
authors: MA
authors: Bredella
authors: Anne
authors: A
authors: Klibanski
authors: Karen K
authors: KK
authors: Miller
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D000855:Anorexia / Q000150:complications* / Q000473:pathology*; D001696:Biomechanical Phenomena; D015519:Bone Density; D003430:Cross-Sectional Studies; D005260:Female; D005269:Femur / Q000473:pathology; D006615:Hip / Q000473:pathology*; D006620:Hip Fractures / Q000453:epidemiology* / Q000209:etiology* / Q000473:pathology; D006801:Humans; D009765:Obesity / Q000150:complications* / Q000473:pathology*; D050177:Overweight / Q000150:complications* / Q000473:pathology*; D012189:Retrospective Studies; D018570:Risk Assessment; D055815:Young Adult