Irritable Bowel Syndrome: More Than Abdominal Pain and Bowel Habit Abnormalities
published online 20 August 2008.
Background & Aims
Although irritable bowel syndrome (IBS) can be defined using few symptoms, principal symptoms alone may be inadequate in monitoring disorder severity. Secondary analysis of a published data set was performed to determine if more inclusive symptom measures would better reflect the burden of this disorder.
Methods
From a prospective naturalistic study of 213 patients meeting Rome II criteria, all the data were used from daily questionnaires recorded for 4 weeks, and repeated again after an interval of 4 weeks. The total number of 11 symptoms and intensity grading score of each symptom were analyzed alongside individual symptom intensities by principal component analysis.
Results
The trend accounting for the most variance was explained by the intensity of all symptoms together. The second largest trend was explained by differences between IBS bowel habits (constipation and diarrhea). The 2 constipation and 4 diarrhea symptoms closely correlated within each group, but the category of other symptoms were not correlated directly with either, and represent a separate dimension. Other symptoms (pain/discomfort, abdominal uneasiness, flatulence/distension, incomplete evacuation, pain or burning in the stomach) correlated more highly with disease intensity than either constipation or diarrhea symptoms. The sum of all symptoms and their intensity was consistent over each week, although the relative intensity of individual symptoms was more variable. Investigator measures of disease intensity underestimated that reported by patients.
Conclusions
Non–bowel habit symptoms include more than abdominal pain and discomfort, and contribute to the largest component of the total symptom burden. Thus, more than bowel habits and abdominal pain drive IBS symptom severity.
∥Institute of Functional and Motor Digestive Disorders, Centro Medico Teknon, Barcelona, Spain
¶Division of Gastroenterology, Washington University School of Medicine, St. Louis, Missouri
Address requests for reprints to: David H. Alpers, MD, Division of Gastroenterology, Washington University School of Medicine, Campus Box 8031, St. Louis, Missouri 63110. fax: (314) 362-8230
Supported by GlaxoSmithKline plc and by a grant from the National Institutes of Health (DK56341).
ABSTRACT