Impact of Coexistent Celiac Disease on Phenotype and Natural History of Inflammatory Bowel Diseases

OBJECTIVES: Inflammatory bowel disease (IBD) and celiac disease are the two most common immune-mediated gastrointestinal diseases. There is limited knowledge regarding the course of IBD in those with coexisting celiac disease. We conducted this study to determine whether patients with coexisting celiac disease present a unique phenotype of IBD and to examine the frequency of co-occurrence of celiac disease and IBD in comparison with other autoimmune disorders. METHODS: This was a case-control study performed at two tertiary referral centers. Cases comprised of patients with known diagnoses of celiac disease and IBD. Two random IBD controls without celiac disease were selected for each case after matching for IBD type. Disease phenotype and natural history for both Crohn's disease (CD) and ulcerative colitis (UC) were noted from medical record review, and were compared between IBD patients with and without celiac disease. RESULTS: We identified a total of 51 patients with IBD (22 UC, 1 indeterminate colitis, 28 CD) and celiac disease. There was no significant difference in the age, gender, or ethnicity between celiac-IBD and controls. Pancolitis was more common in celiac-UC patients as compared with controls (odds ratio (OR) 3.30, 95% confidence interval (CI) 1.05-21.50). There was also a trend toward increased use of immunomodulators (IMMs) among celiac-UC patients than in non-celiac UC controls (OR 2.83, 95% CI 0.95-8.48). No phenotypic differences were found in celiac-CD patients. There were no significant differences in IBD-related medication usage, hospitalizations, or surgeries. CONCLUSIONS: Patients with UC and celiac disease were more likely to have pancolitis and had a trend toward greater use of IMMs. Coexisting celiac disease did not influence natural history of CD.