title: Adiposity is associated with early reduction in bone mass in pediatric inflammatory bowel disease.
abstract: OBJECTIVE
  The effect of adiposity on bone mass in the early phases of inflammatory bowel disease (IBD) in children and adolescents is unclear. The aim of this study was to determine the role of adiposity on bone mass in the first 3 y of diagnosis of IBD. The expected result is that increased adiposity will be associated with increased bone mass in both the controls and IBD subjects.
  
  
  METHODS
  Height-adjusted bone mineral density (BMD) z-scores of 25 subjects, age 13.97 ± 2.70 y, diagnosed with IBD for <4 y were compared to 24 controls, age 13.65 ± 2.60 y. Overweight was defined as BMI of ≥85th but <95th percentile, and obesity as BMI ≥95th percentile. Severity of IBD was determined by the Pediatric Crohn's Disease Activity Index and Lichtiger Colitis Activity Index.
  
  
  RESULTS
  Before stratification by BMI criterion, height-adjusted BMD z-scores were not significantly lower in IBD subjects versus controls for both the femoral neck (-0.8 ± 1.1 versus -0.06 ± 1.1, P = 0.070) and lumbar vertebrae (-0.4 ± 1.2 versus 0.2 ± 1.2, P = 0.086). Following stratification, height-adjusted BMD z-scores were significantly lower in the overweight/obese IBD subjects versus overweight/obese controls for femoral neck (-0.9 ± 0.9 versus 0.3 ± 1.3, P = 0.032); and non-significantly lower for the lumbar spine z-score (-0.4 ± 1.6 versus 0.5 ± 1.3, P = 0.197). BMD z-score had no relationship with the duration of disease, steroid therapy, and the severity of disease.
  
  
  CONCLUSIONS
  Adiposity was associated with reduced bone mass in the early phases of IBD, but with increased bone mass in the controls.
authors.affiliation: Department of Pediatrics, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Nithya
authors.initials: N
authors.lastname: Setty-Shah
authors.affiliation: Department of Quantitative Health Sciences, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
authors.forename: Louise
authors.initials: L
authors.lastname: Maranda
authors.affiliation: Department of Pediatrics, University of Massachusetts Medical School, Worcester, Massachusetts, USA. Electronic address: Benjamin.Nwosu@umassmemorial.org.
authors.forename: Benjamin Udoka
authors.initials: BU
authors.lastname: Nwosu
mesh_terms: D015502:Absorptiometry, Photon; D050154:Adiposity; D000293:Adolescent; D015519:Bone Density; D002648:Child; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000150:complications*; D008159:Lumbar Vertebrae; D008297:Male; D010024:Osteoporosis / Q000150:complications*; D050177:Overweight / Q000150:complications*
keywords: Adiposity; Bone mineral density; Crohn disease; Inflammation; Ulcerative colitis