Long term followup is needed to determine the significance of low bone mineral density (BMD) in children and adolescence with IBD; data with 2 year followup is available (JPGN 2012; 55: 511-18).

In this study from Sweden, 144 patients with IBD were enrolled and 126 were available at 2-year followup (2003-2005).  Among the 144 patients, there were 93 males and 83 with UC. Low BMD was noted in children with both UC and CD for the lumbar spine at baseline and no improvement was noted at 2 years.  Only boys had lower BMD z scores for the lumbar spine (LS) (-1.1); girls had normal LS z scores (0).

While the investigators could not demonstrate catch up in bone mineral density, they note that gains in BMD may accrue beyond late adolescence into early adulthood; this takes place after completion of linear growth.  In the subgroup of subjects in early adulthood, there was improvement in BMD:

• For boys: from -1.7 at baseline (age 17.9) to -0.5 at followup (age 20.0)
• For girls: from -0.4 at baseline (age 17.1) to 0.4 at followup (age 19.2)

With greater use of biologic therapy, these data are likely to change.  Among medical treatments, only biologic therapies have been shown to improve bone formation and improve catchup growth.

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Additional references:

• -JPGN 2011;53: 361. Similar prevalence of low Vitamin D as general population –58% with less than 32.
• -JPGN 2011; 53: 11. Guidelines for low bone mineral density in IBD.
• -JPGN 2009; 48: 538. Need to adjust bone density for bone age.
• -Gastroenterol 2009; 136: 123. Longitudinal bone health study. Steroids did NOT adversely affect bones. n=78.
• -Clin Gastro & Hep 2008; 6: 1378. IFX improves biomarkers of bone formation.
• -J Pediatr 2008; 153: 454, 484. Use of biomarkers of bone turnover in Crohn dz; even when controlling for other factors like delayed bone age, delayed puberty, etc, still evidence of decrease bone formation and increased resorption.
• -JPGN 2007; 45: 538. Ca/Vit D supplements -no change in BMD in IBD patients over 12 months.
• -Clin Gastro & Hep 2007; 5: 721. DXA may not predict risk well.
• -IBD 2007; 4: 416. Inflammation, not steroids, is key factor in bone mineral density.
• -IBD 2006; 13: 42. Natural hx of bone mineral density in IBD; steroid dose did not correlate with BMD. Children did not have “catch up” bone density.
• -JPGN 2006; 43: 597. Crohn’s patients had similar rate of fractures as siblings w/o IBD.
• -Clin Gastro & Hep 2006; 4: 152. Osteoporosis in IBD.
• -IBD 2006; 12: 797. Review of bone mineral density with IBD
• -Clin Gastro & Hepatol 2005; 3: 113-121, 122-132 & editorial 110. In 1st article, budesonide better for bones than other steroids. In 2nd article, unable to show benefit of addition of etidronate to Ca++/Vit D.
• -NEJM 2002; 351: 868. Intermittent steroids in nephrotic syndrome did NOT change bone mineral density.
• -Gastro 2001; 121: 1485-88. Tanning bed Rx of vitamin D deficiency.
• -Gastro 2000; 119: 639-46. Alendronate increases BMD in pts c Crohn’s
• -NEJM 1998; 339: 292-9/ J Bone Miner Res 2000; 15: 1006-13. Bisphosphonates effective in steroid-induced bone disease