Gastroenterology
Volume 136, Issue 1 , Pages 123-130, January 2009

Longitudinal Assessment of Bone Density and Structure in an Incident Cohort of Children With Crohn's Disease

  • Sarah E. Dubner

      Affiliations

    • Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
  • ,
  • Justine Shults

      Affiliations

    • Department of Biostatistics and Epidemiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
  • ,
  • Robert N. Baldassano

      Affiliations

    • Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
  • ,
  • Babette S. Zemel

      Affiliations

    • Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
  • ,
  • Meena Thayu

      Affiliations

    • Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
  • ,
  • Jon M. Burnham

      Affiliations

    • Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
    • Department of Biostatistics and Epidemiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
  • ,
  • Rita M. Herskovitz

      Affiliations

    • Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
  • ,
  • Krista M. Howard

      Affiliations

    • Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
  • ,
  • Mary B. Leonard

      Affiliations

    • Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
    • Department of Biostatistics and Epidemiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania
    • Corresponding Author InformationAddress requests for reprints to: Mary B. Leonard, MD, MSCE, Children's Hospital of Philadelphia, 34th Street and Civic Center Blvd, CHOP North, Room 1564, Philadelphia, Pennsylvania 19104. fax: (215) 590-0604

Received 4 July 2008; accepted 25 September 2008. published online 28 October 2008.

Background & Aims

The impact of childhood Crohn's disease (CD) on volumetric bone mineral density (vBMD), bone structure, and muscle mass have not been established. The objective of this longitudinal study was to assess musculoskeletal outcomes in an incident cohort of children with CD using peripheral quantitative computed tomography (pQCT).

Methods

Tibia pQCT was performed in 78 CD subjects (ages, 5–18 years) at diagnosis and in 67 over the subsequent year. pQCT outcomes were converted to sex- and race-specific z scores based on reference data in over 650 controls. Multivariable linear regression models identified factors associated with changes in bone outcomes.

Results

At diagnosis, CD subjects had significant deficits in trabecular vBMD (z score, −1.32 ± 1.32; P < .001), cortical section modulus (a measure of bone geometry and strength) (z score, −0.44 ± 1.11; P < .01), and muscle (z score, −0.96 ± 1.02; P < .001) compared with controls. Over the first 6 months, trabecular vBMD and muscle z scores improved significantly (both, P < .001); however, section modulus worsened (P = .0001), and all 3 parameters remained low after 1 year. Increases in muscle z scores were associated with less severe declines in cortical section modulus z scores. Improvements in trabecular vBMD z scores were greater in prepubertal subjects. Glucocorticoids were associated with increases in cortical vBMD.

Conclusions

Substantial deficits in trabecular vBMD, cortical bone geometry, and muscle were observed at CD diagnosis. Trabecular vBMD improved incompletely; however, cortical deficits progressed despite improvements in muscle. Glucocorticoids were not associated with bone loss. Therapies to improve bone accrual in childhood CD are needed.

Abbreviations used in this paper: BMD, bone mineral density, CD, Crohn's disease, CortBMD, cortical volumetric bone mineral density, CSA, cross-sectional area, DXA, dual energy x-ray absorptiometry, GC, glucocorticoid, PCDAI, Pediatric Crohn's Disease Activity Index, pQCT, peripheral quantitative computed tomography, TrabBMD, trabecular volumetric bone mineral density, vBMD, volumetric bone mineral density, Zp, polar section modulus

 

 The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center for Research Resources or the National Institutes of Health.

 The authors disclose the following: Supported by grants R01-DK060030 and K24-DK076808 as well as grant number UL1-RR-024134 from the National Center for Research Resources.

PII: S0016-5085(08)01873-8

doi:10.1053/j.gastro.2008.09.072

Refers to article:

  • Boning Up: Exploring Bone Structure and Strength in Children With Crohn's Disease , 01 December 2008

    Catherine M. Gordon
    Gastroenterology January 2009 (Vol. 136, Issue 1, Pages 35-39)

Gastroenterology
Volume 136, Issue 1 , Pages 123-130, January 2009