The association between corticosteroid use and development of fractures among IBD patients in a population-based database.

OBJECTIVES: Because the rate of fracture among patients with inflammatory bowel disease (IBD) is only slightly higher than that in the general population, it is important to define high-risk groups worthy of diagnostic evaluation or prophylactic interventions. Corticosteroid use has been considered in other diseases to be a risk for fracture, although not all studies in IBD are concordant on this point. We aimed to determine whether patients with IBD drawn from a population-based database who sustain fractures are more likely to have been using corticosteroids than a matched group of IBD patients who did not fracture.

METHODS: We extracted from our population-based University of Manitoba Inflammatory Bowel Disease Epidemiology Database the number of patients with a new diagnosis of fracture between the years 1997-2000. From within our Inflammatory Bowel Disease Epidemiology Database, we extracted a control group of IBD patients who did not develop fractures matched to the case group who did by age, gender, diagnosis, year of diagnosis, and geographic area of residence. We linked our cohorts with Manitoba Health's Drug Program Information Network to study corticosteroid use within 2 yr before fracture diagnosis. The Drug Program Information Network is a population-based database, established in 1995, which records all prescription drugs.

RESULTS: Fractures were identified in 13 patients with Crohn's disease and in 28 patients with ulcerative colitis. The control group included 103 Crohn's disease and 173 ulcerative colitis patients who did not fracture. In Crohn's disease, for the group who fractured compared with the controls who did not fracture, corticosteroid use before fracture was evident in seven (54%) compared with 21 (22%) who did not fracture (chi(2) = 4.45, df = 1, p = 0.035). In ulcerative colitis, for the group who fractured compared with the controls who did not fracture, corticosteroid use before fracture was evident in five (18%) compared with 37 (21%) who did not fracture (chi(2) = 0.031, df = 1, p = 0.861). Fracture cases were more likely to be exposed to oral corticosteroids (OR = 1.75; 95% CI = 0.82-3.75), but this result is not significant. Regarding corticosteroid dosing among the 12 patients with IBD who fractured and used corticosteroids, the mean total days supply was 314 days +/- 236 days compared with 258 days +/- 278 days in those who did not fracture (p = 0.16). The prescribed daily dose among corticosteroid users was comparable for those who fractured versus those who did not fracture (18 mg/day vs 21 mg/day, p = 0.90).

CONCLUSIONS: Patients who require corticosteroids in Crohn's disease should be considered at risk for fracture. Further research is required to delineate after how much corticosteroid use are subjects at risk and/or after what duration of active disease.