IBS – Background

IBS - Background

Irritable bowel syndrome (IBS) is a common condition often seen in medical clinics and offices across the country.  It is characterized by abdominal pain or discomfort with defecation, bloating, and changes in bowel habits, and no specific disorder to point to as the cause.  Irritable bowel syndrome is not a new problem.  In the late 1800’s, it was referred to as mucous colitis and still has many names, including spastic colon, nervous colon, and irritable colon.  It is often a chronic problem with relapse.  The Rome III criteria are used to diagnose IBS.  These criteria are clinically based and are used to separate IBS from more serious disorders of known organic causes.  To be called or diagnosed with irritable bowel syndrome, symptoms should be present for at least 3 days a month for 3 months and the onset or start of the disorder at least 6 months before it has been diagnosed by a physician.  A definitive cause of IBS is not known but genetic factors have been suggested since some studies have found clustering in some families.  Many other causes have been proposed but not proven, and these include dietary habits, allergies or food sensitivity, or medications.

The symptoms of irritable bowel syndrome have been linked to psychological factors.  Increased psychological stress (e.g., divorce, relationships, moving, etc.) has been associated with more symptoms.  Also patients with IBS will often have many associated disorders.  These disorders include migraine headaches, urinary frequency and urgency, and nocturia (having to get up repeatedly to urinate at night).

In the U.S., for every 100,000 people, there are approximately 100 to 200 cases of IBS.  Studies also suggest that at any one time, 10-15% of the population have irritable bowel syndrome.  However, only a small percentage of these people will seek professional help.  IBS  is more common in women (14-24%) than men (5-19%).  It usually starts between the age of 30 and 50 and it is rare for it to start in old age.  Racial comparisons show that IBS is just as common in African Americans as it is in Caucasians but is a little less common in Hispanics.

IBS, though problematic to the individual with its decrease in quality of life, does not lead to life-threatening disease or a shortened life span.  It is important to be able to distinguish between IBS and problems with true organic origins.  Some alarming symptoms that should be examined by a physician are increasing pain at night, pain that disturbs sleep, red blood in the stool or black stools, fever, and or weight loss.  These symptoms describe conditions that are more serious and should be worked up by a doctor.


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