IBS affects at least 1 in 10 Americans. Here's what causes it and how it's diagnosed.
Irritable bowel syndrome, or IBS, is among the most common gastrointestinal conditions today. It affects some 10% to 15% of people in the U.S., per the American College of Gastroenterology. A chronic condition that adversely impacts how food and liquids are absorbed, processed and digested through the body's gastrointestinal system, IBS can lead to a variety of unwanted symptoms associated with stomach pain and changes in bowel habits.
Some such symptoms include diarrhea, constipation, gas, bloating, abdominal discomfort, painful bowel movements or feeling like you need to go to the bathroom often, explains Dr. William Chey, a physician and division chief at Michigan Medicine in Ann Arbor and the president-elect of the American College of Gastroenterology.
How is IBS diagnosed?
In order to be diagnosed with IBS, a doctor needs to ascertain the presence of recurrent abdominal pain an average of at least one day a week, says Dr. David Levinthal, a neurogastroenterologist and a director in the gastroenterology, hepatology and nutrition division of the University of Pittsburgh Medical Center.
What's more, he says this pain needs to be related to bowel movements as associated with a change in frequency or related to a change in stool form. Along with such criteria, "IBS is further subtyped based on the dominant stool pattern such as diarrhea (known as IBS-D), constipation (known as IBS-C) or mixes of these patterns (known as IBS-M)," he explains.
CT scans, colonoscopies, and endoscopies are also commonly used to diagnose IBS. Blood testing and stool testing is often also suggested, Chey adds, in order to rule out other causes for symptoms such as inflammation associated with conditions such as celiac disease or chronic infections like giardia.
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What causes IBS?
There are several theories about the origins of IBS, Levinthal says, "but no one really knows for sure." Regardless, one culprit we known can lead to IBS is food sensitivities - especially to foods containing lactose, sorbitol, fructose and other carbohydrates that are poorly absorbed by some people.
Bacteria in the digestive tract can also cause IBS, as can medications such as antibiotics and painkillers. "Many patients with IBS struggle with disordered mood, have experienced traumatic events early in their lives and/or experience ongoing stress or anxiety," says Levinthal. "These observations suggest that at least some part of IBS is rooted in the brain."
Along with food, gut bacteria, medications and brain-gut signaling, Yale Medicine notes that genetics also likely play a part as some of the people who are diagnosed with the condition have a family history of IBS.
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How is IBS treated?
Understanding the cause of one's IBS is crucial to ensure it is adequately treated. For instance, if your IBS is related to food sensitives, diet modification can help resolve issues. "A gluten-free diet, low carbohydrate diet and the Mediterranean diet all have evidence of benefit in randomized, controlled trials," says Chey.
He says that over-the-counter medicines such as Pepto-Bismol, Gas-X and Miralax or prescription options like Lotronex and Viberzi may be recommended "based upon the patient's predominant symptoms." Sometimes psychotherapies such as cognitive behavioral therapy and gut-directed hypnosis are also recommended, adds Chey.
Acupuncture and selected herbal therapies may also be helpful. "Our experience," says Chey, "is that we can improve most IBS patients with integrated care in which we individualize the care plan and bring as many components of evidence-based treatment as is needed."
This article originally appeared on USA TODAY: What causes irritable bowel syndrome IBS?