Learning New IBS Guidelines

IBS is a prevalent and expensive condition that can significantly impair health-related quality of life (HRQOL) and reduce work productivity. Epidemiological studies suggest that 7 percent to10 percent of people worldwide have IBS.

Community-based studies indicate that the subgroup of IBS patients with a mixture of diarrhea and constipation symptoms (IBS-M) occurs more commonly than those with predominantly diarrhea (IBS-D) or constipation (IBS-C), and that switching among subtype groups may occur over time. IBS is 1.5 times more common in women than in men. IBS is more common in lower socioeconomic groups and more commonly diagnosed in patients younger than 50 years. IBS patients make more visits to their physicians, undergo more diagnostic tests, prescribed more medications, miss more workdays, have lower work productivity, are hospitalized more frequently, and account for greater overall direct costs than patients without IBS. Resource utilization is highest in patients with severe symptoms, and poorer HRQOL.

Defining IBS

IBS is defined by the presence of abdominal pain or discomfort that occurs in association with altered bowel habits over a period of at least three to six months. Individual symptoms have limited accuracy for diagnosing IBS and the disorder should be considered as a symptom complex. In clinical research and to a lesser degree clinical practice, IBS is defined by symptom-based criteria such as Kruis, Manning or Rome I, II, or III criteria.

It is widely accepted that the presence of “alarm features” identifies a population of patients in whom the likelihood of organic disease is greater. Unfortunately, the overall diagnostic accuracy of alarm features is disappointing. Rectal bleeding and nocturnal pain offer little discriminative value in separating patients with IBS from those with organic diseases. Although anemia and weight loss have poor sensitivity for organic diseases, they offer reasonably good specificity. As such, in patients who fulfill symptom-based criteria of IBS, the absence of selected alarm features, including anemia, weight loss and a family history of colorectal cancer, inflammatory bowel disease (IBD) or celiac disease, should reassure the clinician that the diagnosis of IBS is correct.