Predictive value of alarm symptoms in Rome IV irritable bowel syndrome: A multicenter cross-sectional study

BACKGROUND: Irritable bowel syndrome (IBS) is a common functional bowel disease that shares features with many organic diseases and cannot be accurately diagnosed by symptom-based criteria. Alarm symptoms have long been applied in the clinical diagnosis of IBS. However, no study has explored the predictive value of alarm symptoms in suspected IBS patients based on the latest Rome IV criteria. AIM: To investigate the predictive value of alarm symptoms in suspected IBS patients based on the Rome IV criteria. METHODS: In this multicenter cross-sectional study, we collected data from 730 suspected IBS patients evaluated at 3 tertiary care centers from August 2018 to August 2019. Patients with IBS-like symptoms who completed colonoscopy during the study period were initially identified by investigators through medical records. Eligible patients completed questionnaires, underwent laboratory tests, and were assigned to the IBS or organic disease group according to colonoscopy findings and pathology results (if a biopsy was taken). Independent risk factors for organic disease were explored by logistic regression analysis, and the positive predictive value (PPV) and missed diagnosis rate were calculated. RESULTS: The incidence of alarm symptoms in suspected IBS patients was 75.34%. Anemia [odds ratio (OR) = 2.825, 95% confidence interval (CI): 1.273-6.267, P = 0.011], fecal occult blood [OR = 1.940 (95%CI: 1.041-3.613), P = 0.037], unintended weight loss (P = 0.009), female sex [OR = 0.560 (95%CI: 0.330-0.949), P = 0.031] and marital status (P = 0.030) were independently correlated with organic disease. The prevalence of organic disease was 10.41% in suspected IBS patients. The PPV of alarm symptoms for organic disease was highest for anemia (22.92%), fecal occult blood (19.35%) and unintended weight loss (16.48%), and it was 100% when these three factors were combined. The PPV and missed diagnosis rate for diagnosing IBS were 91.67% and 74.77% when all alarm symptoms were combined with Rome IV and 92.09% and 34.10% when only fecal occult blood, unintended weight loss and anemia were combined with Rome IV, respectively. CONCLUSION: Anemia, fecal occult blood and unintended weight loss have high predictive value for organic disease in suspected IBS patients and can help identify patients requiring further examination but are not recommended as exclusion criteria for IBS.