title: Skeletal outcomes by peripheral quantitative computed tomography and dual-energy X-ray absorptiometry in adolescent girls with anorexia nervosa.
abstract: We conducted the first comparison of dual-energy X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT) outcomes in adolescent girls with anorexia nervosa. We observed deficits in bone density by both tools. pQCT assessments were associated with many of the same clinical parameters as have been previously established for DXA.
  
  
  
  Adolescents with anorexia nervosa (AN) commonly exhibit bone loss, but effects on bone geometry are less clear. We compared measures obtained by DXA and pQCT in girls with AN.
  
  
  
  Seventy females (age 15.5 ± 1.9 years ) with AN and 132 normal-weighted controls underwent tibial measures by pQCT including trabecular volumetric bone mineral density (vBMD) at the 3 % site, cortical vBMD and dimensions at the 38 % site, and muscle cross-sectional area (CSA) at the 66 % site. Participants with AN also underwent standard DXA measures. Independent t tests compared the pQCT results, while Pearson coefficient assessed correlations among DXA and pQCT measures.
  
  
  
  Trabecular vBMD Z-scores were lower in AN compared to controls (AN -0.31 ± 1.42 vs +0.11 ± 1.01, p = 0.01) and cortical vBMD Z-scores were higher (AN +0.18 ± 0.92 vs -0.50 ± 0.88, p < 0.001). Trabecular vBMD and cortical CSA Z-scores positively correlated with DXA BMD Z-scores (r range 0.57-0.82, p < 0.001). Markers of nutritional status positively correlated with Z-scores for trabecular vBMD, cortical CSA, section modulus, and muscle CSA (p < 0.04 for all).
  
  
  
  This study is the first to compare DXA and pQCT measurements in adolescent girls with AN. We observed deficits in BMD by both DXA and pQCT. pQCT assessments correlated well with DXA bone and body composition measures and were associated with many of the same clinical parameters and disease severity markers as have been previously established for DXA. The differences in cortical vBMD merit further study.
authors.affiliation: Division of Adolescent Medicine, Boston Children's Hospital and Harvard Medical School, 333 Longwood Avenue, Boston, MA, 02115, USA. amy.divasta@childrens.harvard.edu.|Division of Gynecology, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA. amy.divasta@childrens.harvard.edu.
authors.forename: A D
authors.initials: AD
authors.lastname: DiVasta
authors.affiliation: Clinical Research Program, Boston Children's Hospital, Boston, MA, USA.|Division of Endocrinology, Boston Children's Hospital, Boston, MA, USA.
authors.forename: H A
authors.initials: HA
authors.lastname: Feldman
authors.affiliation: Rutgers-Robert Wood Johnson Medical School, New Brunswick, NJ, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: O'Donnell
authors.affiliation: Division of Pediatric Nephrology, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: J
authors.initials: J
authors.lastname: Long
authors.affiliation: Division of Pediatric Nephrology, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: M B
authors.initials: MB
authors.lastname: Leonard
authors.affiliation: Division of Adolescent and Transition Medicine, Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH, USA.
authors.forename: C M
authors.initials: CM
authors.lastname: Gordon
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000856:Anorexia Nervosa / Q000473:pathology*; D015519:Bone Density; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D013977:Tibia / Q000473:pathology*; D014057:Tomography, X-Ray Computed
keywords: Anorexia nervosa; DXA; Malnutrition; Peripheral quantitative computed tomography