Risk of diagnosed fractures in children with inflammatory bowel diseases

Abstract

Decreased bone mass is common in children with inflammatory bowel disease (IBD); however, fracture risk is unknown. We sought to evaluate fracture risk in children with IBD as compared to unaffected controls and determine whether this risk is affected by geographical region (a proxy for sun/vitamin D exposure) and oral steroid use. We identified cases of Crohn's disease (CD) and ulcerative colitis (UC), less than 20 years of age, using administrative data from 87 health plans. Each case was matched to three controls on the basis of age, gender, and geographical region. We identified fractures in cases and controls using ICD-9 diagnosis codes and measured oral steroid exposure using NDC codes. The study included 733 children with CD, 488 with UC, and 3287 controls (mean age 15 years). IBD was not associated with a higher risk of fracture at any site (CD odds ratio [OR] 0.8, 95% confidence interval [CI] 0.6-1.1; UC OR 1.4, 95% CI 1.0-2.1) or at multiple sites (CD OR 0.8, 95% CI 0.4-1.7; UC OR 0.4, 95% CI 0.1-1.4). Among IBD patients we did not identify any significant differences in the fracture rate between those residing in the Northeast/Midwest versus the South (OR 1.3, 95% CI 0.8-2.2). Steroid exposure was not associated with the occurrence of fractures (P = 0.6). Children with IBD are no more likely to have experienced a diagnosed fracture than age-, sex-, and gender-matched controls.