Metabolic Comorbidities as Independent Predictors of Microscopic Colitis in Diarrhoea-Predominant Irritable Bowel Syndrome Patients

Abstract

Background: Microscopic colitis (MC) is frequently misdiagnosed as diarrhoea-predominant irritable bowel syndrome (IBS-D) due to overlapping symptoms and normal endoscopic appearance. The role of metabolic comorbidities such as diabetes mellitus (DM) and hypertension (HTN) as independent predictors of MC remains underexplored, particularly in the people of South Asia. This study aimed to determine the frequency of MC in IBS-D patients and specifically evaluate metabolic comorbidities. Materials and Methods: A cross-sectional observational study was conducted at the Department of Gastroenterology, Bangladesh Medical University (BMU), from July 2023 to December 2024. A total of 223 IBS-D patients fulfilling Rome IV criteria underwent full colonoscopy with multi-segment biopsies. Histological examination was carried out using H&E and Masson’s trichrome staining techniques. Multivariate logistic regression was used to identify independent predictors of MC. Results: MC was identified in 51 (22.87%) of IBS-D patients in which 34 (66.7%) lymphocytic colitis and 17 (33.3%) collagenous colitis. Diabetes mellitus (50.99% vs 12.8%; p<0.05) and hypertension (54.9% vs 14.5%; p<0.05) were significantly more prevalent in MC patients. On multivariate regression, hypertension (AOR: 1.91, 95% CI: 1.50-2.42, p=0.001), DM (AOR: 1.65, 95% CI: 1.23-2.22, p=0.001), thyroid disorder (AOR: 1.80, p=0.015), statin use (AOR: 2.04, 95% CI: 1.54-2.68, p=0.001), and PPI use (AOR: 1.35, p=0.002) were independent predictors of MC. Conclusion: Metabolic comorbidities, particularly DM and HTN, are significant independent predictors of MC in IBS-D patients. Routine histopathological evaluation should be prioritized in IBS-D patients with metabolic comorbidities or prolonged statin and PPI use.

Eastern Med Coll J. January 2026 Vol.11 No.1 : 66-70