To Örebro University

INTRODUCTION: Most studies on fractures in inflammatory bowel disease (IBD) are based on patients from tertiary centers or patients followed up before the introduction of immunomodulators or biologics. In addition, the role of corticosteroids in fracture risk has rarely been examined.

METHODS: We conducted a nationwide population-based cohort study of 83,435 patients with incident IBD (ulcerative colitis [UC]: n = 50,162, Crohn's disease [CD]: n = 26,763, and IBD unclassified: 6,510) and 825,817 reference individuals from 1964 to 2014. Using multivariable Cox regression, we estimated hazard ratios (HRs) for hip fracture and any fracture and the association with cumulative corticosteroid exposure.

RESULTS: During 1,225,415 person-years of follow-up in patients with IBD, there were 2,491 first-time hip fractures (203/100,000 person-years) compared with 20,583 hip fractures during 12,405,642 person-years in reference individuals (159/100,000 person-years). This corresponded to an HR of 1.42 (95% confidence interval [CI] = 1.36-1.48). The risk for hip fracture was higher in CD compared with UC (P < 0.001). Inflammatory bowel disease was also associated with any fracture (IBD: HR = 1.18; 95% CI = 1.15-1.20). Hazard ratios for hip fracture had not changed since the introduction of immunomodulators or biologics. Increasing exposure to corticosteroids was associated with hip fracture in both IBD and non-IBD individuals (P < 0.001), but only in elderly (>60 years) patients with IBD. The association between IBD and hip fracture was nonsignificant among individuals without corticosteroids (HR = 1.11; 95% CI = 0.86-1.44).

CONCLUSIONS: Inflammatory bowel disease (CD and UC) is associated with an increased risk of hip fracture and any fracture, but not in individuals without a history of corticosteroid treatment. The association between corticosteroids and hip fracture was restricted to elderly patients with IBD.