Altered bone metabolism in inflammatory bowel disease

Am J Gastroenterol. 1997 Jul;92(7):1157-63.


A reduced bone mineral density has been reported in inflammatory bowel disease (IBD).

Objective: To assess the mechanisms of bone disease in IBD.

Methods: We studied in 90 patients (61 with Crohn's disease, 22 with ulcerative colitis, 7 with indeterminate colitis) biochemical markers of bone metabolism in serum and bone mineral density by peripheral quantitative computed tomography at the forearm.

Results: Forty-five percent of the patients had a reduced bone density (Z score < -1). Serum calcium was normal in most patients, vitamin D deficiency was documented in 17%. Osteocalcin, a serum marker of bone formation, was decreased in 26% (1.2 +/- 0.1 ng/ml), whereas the carboxyterminal cross-linked telopeptide of type I collagen (ICTP), a recently described serum parameter of bone breakdown, was stimulated in 38% (10.4 +/- 2.3 microg/L). Of 33 patients with increased ICTP levels, 19 showed a decreased bone density (Z score < -1), and 2 of them never received steroids. An active status of the underlying disease in most patients with increased ICTP levels suggests a direct effect of the underlying IBD. In the whole series of patients with a history of active disease (n = 34), 47% had signs of an increased bone degradation (ICTP > 5 microg/L; mean, 12.9 +/- 4.7 microg/L). Data derived from a retrospective survey of 245 patients with IBD suggest that the prevalence of bone fractures in IBD is unexpectedly high, particularly in patients with a long duration of disease, frequent active phases, and high cumulative doses of corticosteroid intake.

Conclusions: Several mechanisms may be involved in IBD-associated bone disease: (1) a high inflammatory activity directly induces bone degradation via yet unknown pathways, (2) treatment with corticosteroids may exert catabolic effects on the bone, or (3) malabsorption and vitamin D deficiency may activate bone turnover.

MeSH terms

  • Adolescent
  • Adult
  • Biomarkers / blood
  • Bone Density*
  • Bone and Bones / metabolism*
  • Colitis / metabolism
  • Colitis, Ulcerative / metabolism
  • Crohn Disease / metabolism
  • Cross-Sectional Studies
  • Female
  • Humans
  • Inflammatory Bowel Diseases / blood
  • Inflammatory Bowel Diseases / metabolism*
  • Male
  • Middle Aged
  • Retrospective Studies


  • Biomarkers