Irritable Bowel Syndrome Prevalence in Patients with Inflammatory Bowel Disease in Remission: Single-Center Experience

Background: Irritable bowel syndrome (IBS) and inflammatory bowel diseases (IBD) are characterized by features of abdominal pain and changes in bowel habits, making it hard to differentiate between the two. Early studies that estimated prevalence of IBS in IBD patients defined remission based only on clinical scores, potentially overestimating IBS symptoms and underestimating subclinical inflammation. The aim of this study was to determine prevalence of IBS in IBD patients who are treated with biologics and have reached clinical, biologic and endoscopic remission, thereby applying a more stringent definition of remission. Methods: This single-center cross-sectional study included 136 patients (68 patients with Crohn’s disease and 68 with ulcerative colitis) who are treated with biologics from December 2022 to June 2023 and have reached clinical, biologic and endoscopic remission. Clinical remission was defined as Crohn’s disease activity index (CDAI) ≤ 150 for patients with Crohn’s disease (CD), and Mayo partial score ≤ 1 for patients with ulcerative colitis (UC). Biologic remission was defined as faecal calprotectin (FCP) ≤ 250 ug/g, and endoscopic remission was defined as the absence of ulcerations for CD and Mayo subscore ≤ 1 for UC patients. The presence of IBS was defined by Rome IV criteria. Results: A total of 28 (20.6%) patients in complete remission reported symptoms consistent with IBS, based on Rome IV criteria. The prevalence of IBS was higher in patients with Crohn’s disease than in those with ulcerative colitis (CD 27.9% (19/68) vs UC 13.2% (9/68), p = 0.034). Females and smokers with Crohn’s disease are more likely to report IBS symptoms. Conclusion: Prevalence of IBS symptoms in IBD patients varies according to how remission is defined. When using stringent clinical, biological and endoscopic remission criteria, 20% of patients present with IBS symptoms, more commonly in those with CD. Keywords: IBS, IBD, prevalence