Irritable bowel syndrome according to varying diagnostic criteria: Are thenew Rome II criteria unnecessarily restrictive for research and practice?

OBJECTIVES: It has been suggested that the variation in the prevalence of i rritable bowel syndrome (IBS) may be due to the application of different di agnostic criteria. New criteria for IBS have been proposed (Rome LI). It is unknown whether persons meeting different criteria for IBS have similar ps ychological and symptom features. The aim of this study was to measure the prevalence of IBS according to Manning and Pome definitions of IBS and to e valuate the clinical and psychological differences between diagnostic categ ories. METHODS: A total of 4500 randomly selected subjects, with equal numbers of male and female subjects aged greater than or equal to 18 yr and representa tive of the Australian population, took part in this study. Subjects were m ailed a questionnaire (response rate, 72%). Characteristics measured were g astrointestinal symptoms over the past 12 months, neuroticism and extrovers ion (Eysenck Personality Questionnaire), anxiety and depression (Delusions- Symptoms-States Inventory), mental and physical functioning (SF-12), and so matic distress (Sphere). RESULTS: The prevalence for IBS according to Manning, Rome I, and Pome II w as 4.4% (95% confidence interval [CI] = 3.5-5.1%), 6.9% (CI 6.0-7.8%), and 13.6% (CI 12.3-14.8%), respectively. Only 12 persons with Rome I did not al so meet Pome LI criteria; 196 persons with Manning criteria did not meet Po me II cut-offs. Having IBS regardless of which criteria were used was signi ficantly associated with psychological morbidity, but psychological factors were not important in discriminating between diagnostic categories. Howeve r, pain and bowel habit severity independently discriminated between diagno stic groups. CONCLUSIONS: IBS is a relatively common disorder in the community. The new Pome II criteria may be unnecessarily restrictive in practice. (C) 2000 by Am. Cell. of Gastroenterology).