Irritable bowel syndrome (IBS) is a collection of symptoms that may include constipation or diarrhea. It's pretty uncomfortable—all that abdominal pain and, well, bowel irritation. Researchers in Los Angeles looked at which factors have the biggest effect on quality of life for irritable bowel patients.

What the researchers wanted to know: What determines health-related quality of life for irritable bowel patients?

What they did: The researchers had 770 patients with irritable bowel syndrome fill out the "SF-36," a widely-used questionnaire that evaluates health-related quality of life. All of the patients visited the Center for Neurovisceral Sciences and Women's Health at UCLA's medical school between 1995 and 2002.

What they found: Several factors had a significant influence on health-related quality of life, including having to visit the doctor more than five times in the last year, getting tired easily, and feeling tense. Some factors that didn't have a big effect on quality of life were having had the symptoms for more than two years and specific symptoms, such as having diarrhea more often than constipation.

What the study means to you: Doctors treating IBS often focus on things like how often you produce a stool and what consistency it has. But this suggests that the real problems for patients aren't the messed-up bowels but the accompanying stress and exhaustion. Since IBS is a collection of symptoms, not one disease, it helps to pinpoint the worst aspects, so doctors and patients can target those symptoms and pay attention to whether they're improving.

Caveats: Since this was a university clinic, a lot of patients had been referred from somewhere else, after the first-line therapies for IBS failed.

Find out more: Learn about irritable bowel syndrome from the National Institute of Diabetes and Digestive and Kidney Diseases.

Read the article: Spiegel, B.M.R. et al. "Clinical Determinants of Health-Related Quality of Life in Patients With Irritable Bowel Syndrome." Archives of Internal Medicine. Sept. 13, 2004, Vol. 164, pp. 1773–1780.

Abstract online: http://archinte.ama-assn.org