Association Between Celiac Disease and Irritable Bowel Syndrome: A Nationwide Cohort Study

Abstract

Background & aimsTo determine the risk of irritable bowel syndrome (IBS) diagnosis in patients with celiac disease (CD) compared to general population comparators. MethodsUsing Swedish histopathology and register-based data, we identified 27,262 patients with CD diagnosed in 2002-2017 and 132,922 age- and sex-matched general population comparators. Diagnoses of IBS were obtained from nationwide inpatient and non-primary outpatient records. Cox regression estimated hazard ratios (aHRs) for IBS adjusted for education level and Charlson Comorbidity Index. To reduce potential surveillance bias our analyses considered incident IBS diagnosis ≥1 year after CD diagnosis. Using conditional logistic regression, secondary analyses were calculated to estimate odds ratios (ORs) for IBS diagnosis ≥1 year before CD diagnosis. ResultsDuring an average of 11.1 years of follow-up, 732 (2.7%) celiac patients were diagnosed with IBS vs. 1,131 (0.9%) matched general population comparators. Overall (≥1 year of follow-up), the aHR for IBS was 3.11 (95% confidence interval, CI=2.83-3.42), with an aHR of 2.00 (95%CI=1.63-2.45) after ≥10 years of follow-up. Compared to siblings (n=32,010), celiac patients (n=19,211) had a ≥2-fold risk of later IBS (aHR=2.42; 95%CI=2.08-2.82). Compared to celiac patients with mucosal healing, those with persistent villus atrophy on follow-up biopsy were less likely to be diagnosed with IBS (aHR=0.66; 95%CI=0.46-0.95). CD was also associated with having an earlier IBS diagnosis (OR=3.62; 95%CI=3.03-4.34). ConclusionsIn patients with CD, the risk of IBS is increased long before and after diagnosis. Clinicians should be aware of these long-term associations and their implications on patient management.