Inflammatory Bowel Disease Defined
By: Sunanda V. Kane, MD, MSPH

IBD is characteristically a lifelong (chronic) condition in which there is inflammation of the lining of the gastrointestinal tract for no apparent reason. The inflammation might be located just in one part of the digestive tract, for example, in the large intestine (colon), but it can appear anywhere along the digestive tract, from the mouth to the anus. IBD occurs as two major types and two rare types. Crohn’s Disease and Ulcerative Colitis are the two diseases that most people recognize because they are the most common.

More than 1 million Americans have IBD, and right now this is equally split between Crohn’s Disease and Ulcerative Colitis. However, this balance is likely to change because the number of new cases of Crohn’s Disease is on the rise, although the reason behind this trend is not entirely clear. Each year, approximately 10 people per 100,000 are diagnosed with Ulcerative Colitis and 16 people per 100,000 are diagnosed with Crohn’s Disease.

It is most common to develop IBD between the ages of 15 and 35. However, children as young as three have been diagnosed, and there is a second peak of diagnosis between ages 50 and 55. Equal numbers of men and women get IBD.