Epidemiologic, Clinical, and Psychological Characteristics of Individuals With Self-Reported Irritable Bowel Syndrome Based on the Rome V vs Rome IV Criteria

Background & Aims The Rome V process altered diagnostic criteria for irritable bowel syndrome (IBS) compared with Rome IV, by modifying the requirement for frequency and persistence of symptoms. We compared epidemiologic, clinical, and psychological characteristics of people with Rome V–defined IBS, vs Rome III or IV, in the community. Methods We conducted a survey of adults in the United Kingdom with self-reported IBS. Participants completed validated questionnaires assessing the Rome III, IV, and V criteria, gastrointestinal symptom severity, quality of life, and psychological comorbidity. The proportions of people meeting criteria for IBS were compared across definitions, including a sensitivity analysis related to the exclusion of individuals with continuous pain from the Rome V definition of IBS. Agreement between the various criteria was evaluated using a Kappa statistic. The characteristics of those meeting the 3 iterations of the criteria, and the stability of the criteria during longitudinal follow-up, were compared. Results In the main analysis, excluding those who reported continuous abdominal pain on every day of the week from the Rome V definition of IBS, among 1275 respondents with complete data, 995 (78.0%) met the Rome III, 752 (59.0%) the Rome IV, and 893 (70.0%) the Rome V criteria for IBS. Agreement between the Rome V criteria and the Rome III or the Rome IV criteria was substantial to fair (Kappa = 0.75 and 0.40, respectively). Compared with individuals meeting the Rome IV criteria, those meeting the Rome V criteria reported significantly lower symptom severity, less psychological comorbidity, a reduced impact on ability to work and participate in social activities, and higher quality of life scores. Rome V IBS was less stable than Rome IV IBS during longitudinal follow-up. Conclusions Applying the Rome V criteria changes the population classified as having IBS, mainly due to the exclusion of those with continuous pain, identifying a clinically less severe cohort. This may have implications for research and clinical practice.