The risk of inflammatory bowel disease is increased in celiac disease but not in dermatitis herpetiformis

Abstract

Background: Although an association between celiac disease and inflammatory bowel disease (IBD) has been recognized, there remains limited research on the subject. Comorbidities vary between the phenotypes of celiac disease, but the risk of IBD in the extraintestinal manifestation of celiac disease, dermatitis herpetiformis (DH), has been previously studied mainly through case reports. This study aimed to compare the risk of IBD between celiac disease and DH patients and references. Methods: The study population consisted of 1,072 celiac disease and 368 DH patients with biopsy-proven diagnosis performed between 1969 and 2000. Three reference individuals matched for age, sex, and place of residence were taken from the population register for each patient. Cox proportional hazards model was used for assessing the risk for the diseases studied. Results: The risk of IBD was higher in celiac patients than in the references (HR 2.77, 95% CI 1.81–4.26), with heightened risk in both ulcerative colitis (HR 2.73, 95% CI 1.71–4.83) and Crohn's disease (HR 2.54, 95% CI 1.19–5.43). The risk of IBD did not differ statistically between DH patients and their references (HR 1.72, 95% CI 0.75–3.93). Conclusion: Celiac disease is associated with an increased risk of IBD. The risks of Crohn's disease and ulcerative colitis were equally increased. A smaller but not statistically significant increase was observed in DH. It is advisable to consider the possibility of IBD when managing patients with celiac disease.