Chapter 9 IRRITABLE BOWEL SYNDROME
DEFINITIONS AND CATEGORIES
If there is no structural abnormality to explain the symptoms, and symptoms such as pain or discomfort are associated with changes in bowel habit, irritable bowel syndrome (IBS) can be diagnosed. The most stringent definitions for functional gastrointestinal disorders have been provided by the Rome Committee, an international working party. The Rome III criteria for IBS are summarised in Table 9.1. Essentially, IBS can be diagnosed when structural lesions are absent (or unlikely based upon the clinical presentation) and the patient suffers from chronic or relapsing abdominal discomfort or pain associated with an abnormality of bowel movements (constipation, diarrhoea or alternating diarrhoea and constipation). Bloating is also common.
Recurrent abdominal pain or discomfort for at least 3 months, and symptoms at least 3 days/month associated with two or more of the following: |
EPIDEMIOLOGY
The prevalence of IBS ranges from 10% to 20% in Western countries, and it is just as common in India, Japan and China. Only one out of three people who have symptoms of IBS seek medical attention. Generally, those who have more severe symptoms seek medical help. IBS is more prevalent in females. While IBS is not life-threatening, it is remarkable that affected patients have a substantial number of days off work, and thus society has to cope with the burden of IBS too.