title: Reduced bone mass and preserved marrow adipose tissue in patients with inflammatory bowel diseases in long-term remission.
abstract: Bone marrow adipose tissue has not been studied in patients with inactive inflammatory bowel disease. We found that these patients have preserved marrow adiposity even with low bone mass. Factors involved in bone loss in active disease may have long-lasting effects but do not seem to affect bone marrow adiposity.
  
  
  
  Reduced bone mass is known to occur at varying prevalence in patients with inflammatory bowel diseases (IBD) because of inflammation, malnutrition, and steroid therapy. Osteoporosis may develop in these patients as the result of an imbalanced relationship between osteoblasts and adipocytes in bone marrow. This study aimed to evaluate for the first time bone mass and bone marrow adipose tissue (BMAT) in a particular subgroup of IBD patients characterized by long-term, steroid-free remission.
  
  
  
  Patients with Crohn's disease (CD; N = 21) and ulcerative colitis (UC; N = 15) and controls (C; N = 65) underwent dual X-ray energy absorptiometry and nuclear magnetic resonance spectroscopy of the L3 lumbar vertebra for BMAT assessment.
  
  
  
  Both the CD and UC subgroups showed significantly higher proportions of patients than controls with Z-score ≤-2.0 at L1-L4 (C 1.54%; CD 19.05%; UC 20%; p = 0.02), but not at other sites. The proportions of CD patients with a T-score ˂-1.0 at the femoral neck (C 18.46%; CD 47.62%; p = 0.02) and total hip (C 16.92%; CD 42.86%; p = 0.03) were significantly higher than among controls. There were no statistically significant differences between IBD patients and controls regarding BMAT at L3 (C 28.62 ± 8.15%; CD 29.81 ± 6.90%; UC 27.35 ± 9.80%; p = 0.67).
  
  
  
  IBD patients in long-term, steroid-free remission may have a low bone mass in spite of preserved BMAT. These findings confirm the heterogeneity of bone disorders in IBD and may indicate that factors involved in bone loss in active disease may have long-lasting effects on these patients.
authors.affiliation: Gastroenterology Division, Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Av Bandeirantes 3900, Ribeirão Preto, SP, 14049-900, Brazil. bastosclara@yahoo.com.br.
authors.forename: C M
authors.initials: CM
authors.lastname: Bastos
authors.affiliation: Endocrinology Division, Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: I M
authors.initials: IM
authors.lastname: Araújo
authors.affiliation: Radiology Division, Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: M H
authors.initials: MH
authors.lastname: Nogueira-Barbosa
authors.affiliation: Department of Physics, Ribeirão Preto Faculty of Philosophy, Sciences and Letters, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: C E G
authors.initials: CEG
authors.lastname: Salmon
authors.affiliation: Endocrinology Division, Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: F J A
authors.initials: FJA
authors.lastname: de Paula
authors.affiliation: Gastroenterology Division, Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Av Bandeirantes 3900, Ribeirão Preto, SP, 14049-900, Brazil.
authors.forename: L E A
authors.initials: LEA
authors.lastname: Troncon
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods; D000273:Adipose Tissue / Q000473:pathology*; D000328:Adult; D015519:Bone Density / Q000502:physiology; D001853:Bone Marrow / Q000473:pathology*; D016022:Case-Control Studies; D003093:Colitis, Ulcerative / Q000150:complications / Q000473:pathology / Q000503:physiopathology; D003424:Crohn Disease / Q000150:complications / Q000473:pathology / Q000503:physiopathology; D005260:Female; D005272:Femur Neck / Q000503:physiopathology; D006621:Hip Joint / Q000503:physiopathology; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000150:complications* / Q000473:pathology / Q000503:physiopathology; D008159:Lumbar Vertebrae / Q000503:physiopathology; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D055815:Young Adult
keywords: Bone marrow adipose tissue; Bone mass; Crohn’s disease; Inflammatory bowel diseases; Ulcerative colitis