Natural History and Disease Impact of Rome IV versus Rome III Irritable Bowel Syndrome: A Longitudinal Follow-up Study

ABSTRACT Objectives Irritable bowel syndrome (IBS) is a chronic functional bowel disorder diagnosed using the Rome criteria, which have evolved since their original description 30 years ago. Little is known about the effects on the natural history of IBS of moving to the latest iteration, Rome IV, from the previous Rome III criteria. We conducted a 12-month longitudinal follow-up study examining this. Methods We collected complete demographic, symptom, mood, and psychological health data at baseline from 1097 adults who self-identified as having IBS and met either Rome IV or III criteria. At 12 months, we collected data regarding IBS symptom severity and impact, consultation behavior, treatments commenced, and psychological health. We examined whether subsequent disease behavior in Rome IV or Rome III-defined IBS differed. Results At 12 months, 638 (58.2%) of the 1097 participants were successfully followed up. Of these, 452 met Rome IV criteria and 186 met Rome III criteria at baseline. During the 12-month study period, individuals with Rome IV IBS were significantly more likely to have seen a primary care physician (44.7% vs 28.5%, p Conclusions The natural history of IBS defined according to Rome IV criteria is more severe than that of Rome III-defined IBS. This has important implications for future treatment trials in IBS.