Sept. 21, 2000 -- As the second leading cause of missing work and close to 35 million Americans suffering its effects, it's no wonder that irritable bowel syndrome (IBS) is gaining attention from the public, and most importantly, the medical community who may be one step closer to determining its cause.
Now, a study in the September issue of Mayo Clinic Proceedings shines light on the mysterious origins of IBS by showing that those who had a first-degree relative -- either parents or siblings -- with abdominal pain or bowel problems were more than twice as likely to have irritable bowel syndrome and stomach acid problems.
"Our study confirms for the first time what we have long thought and heard anecdotally from our patients -- that a relative often has their similar symptoms," researcher G. Richard Locke III, MD, tells WebMD. "What was most surprising is that our results show the family link is not just related to IBS, but other gastrointestinal disorders as well." Locke is a consultant in the division of gastroenterology and department of internal medicine at the Mayo Clinic in Rochester, Minn. Locke is also an assistant professor of medicine at the Mayo Medical School.
In order to determine if IBS -- a medical disorder that describes a group of chronic symptoms such as abdominal pain, bloating, constipation, and/or diarrhea -- may be inherited, the study surveyed almost 650 people. Of them, 12% reported IBS and 14% had stomach acid problems. As many as 24% had a first-degree relative or a spouse with abdominal or bowel problems, with the family connection of IBS being the strongest.
"This is the first needed step to look into the possibility of IBS running in families. Now we are addressing the issue of nature vs. nurture. Is it truly genetics or is it environmental issues that most contribute to IBS," says Locke.
William E. Whitehead, PhD, who is the co-director for Functional GI and Motility Disorders at the University of North Carolina, says that there is evidence of both the genetic and the circumstantial causes of IBS.
"We have found that children of parents who have IBS are more likely to be brought into the doctor for the same symptoms, and this may be that they simply learn to pay more attention to the symptoms of this condition," Whitehead tells WebMD. "If we find that 'family learning' is indeed contributing to IBS, it may add to the possible treatments for the condition but not as much as a genetic link would allow."
While IBS and where it comes from may remain a mystery, Locke stands firmly by the direction current research is taking. "If a genetic link is to blame for IBS, then a diagnosis could be made more quickly and easily for the patients and their family."