Irritable bowel syndrome or IBS is a common medical condition in which the digestive system doesn't function normally. Satish Rao, MD, director of neurogastroenterology and gastrointestinal motility at University of Iowa Hospitals and Clinics, talks about IBS:

How many people are affected by irritable bowel syndrome?

IBS is a very common problem that affects up to 15 percent of the U.S. population.

What are the signs and/or symptoms of IBS?

There are three cardinal manifestations of this disorder. Abdominal pain may either be mild to moderate discomfort or clearly significant pain. This pain is associated with three common manifestations:

• Abdominal bloating or distention, sometimes they feel that they're six or seven months pregnant; other folks develop significant
• Constipation with either infrequent bowel movements or excessive straining or difficulty with evacuation; and the third group of individuals have
• Pain with diarrhea

So diarrhea, constipation, or bloating and distention together with pain are the chief symptoms of this disorder.

Are there different kinds or variations of IBS?

Yes, as I just mentioned, we categorize the IBS patients into the three major groups:

• Constipation group
• Diarrhea group
• Mixed group - may have constipation, diarrhea, or bloating and distention

Those are the usual varieties of IBS.

Until recently, we would largely diagnose IBS on the basis of excluding other common GI disorders because the symptoms mentioned really mimic any other disorders, be it peptic ulcer disease or cancer of the bowel or whatever. It mimics all the other disorders, so we used to typically diagnose the condition by excluding other disorders. But today, I think we have certain important symptom criteria that we can use that can help us to make a diagnosis in the clinic without necessarily having to go through a large spectrum of tests to exclude other disorders.

Can stress trigger irritable bowel syndrome?

That's an excellent question. It has been felt for years that maybe stress is the major triggering factor for IBS. But we now know that that is not the case, in fact there are several studies that have been conducted to examine this very meticulously. But many folks with IBS do have psychological symptoms, such as anxiety maybe, depression, and so on and so forth. Often we believe this is a core factor and not necessarily a trigger factor.   Stress can trigger any illness in the body, so IBS is no exception. But stress is not, per se, the main underlying mechanism that leads to IBS.

Can certain foods trigger IBS?

Now that is very important. Over the years we recognized that there are several food items that can trigger unexplained abdominal symptoms. For example, about 20-25 years ago, we discovered that lactose, which is a sugar present in milk, can trigger unexplained pain, diarrhea, and bloating. Then we identified lactose intolerance and we no longer called these people IBS. More recently, I think it's important - particularly for us in Iowa as we've championed this particular discovery - is the condition called fructose intolerance. Fructose is fruit sugar and we are increasingly, as a nation, consuming a lot of fructose, particularly from corn and other products, and colas, and so on. Fructose, unfortunately, has very limited absorptive capacity in the body, and if we overwhelm the capacity, then we can get pain, bloating, diarrhea, and constipation, such as IBS symptoms. So these are some of the food items that can, and there are other food items that we know, such as proteins, seafood, and so on, that can trigger IBS-like symptoms.

Can people do certain steps on their own to control irritable bowel syndrome?

I think the first important thing is to eat healthy foods. Avoid junk food, particularly a lot of cola containing compounds, eat at regular times, and eat adequate fiber. Americans in general take about 6 to 7 grams of fiber, which is too little. We should aim to take between 15 to 20 grams of fiber and that's adequate. If you take in that much of fiber, you don't have to worry about fiber intake. So eating a balanced diet, I think, is very important, and leading a balanced life is very important. If you're doing all those and you're still having symptoms, then that needs further help with medical attention.  

When should someone see their physician with symptoms?

I think if the pain is very bothersome, they should see their physicians immediately. If it's just mild discomfort or just someone who has had a regular bowel habit and now has become a little irregular, I think they can wait two to four weeks, maybe change the diet a little bit, and see if symptoms get better, drink adequate fluids, and so on. And if not, they should go and see their physician straight away.

What is the current treatment for IBS?

Until recently, we used to treat patients based on symptoms. But in the last five to 10 years, there have really been some new drugs that have been FDA approved.

One drug is locitrana lotronex. This was approved in about 1998-99, but was withdrawn by the FDA for a couple of years; and again, re-approved with some limited prescriptions. It is widely available and primarily used for patients with irritable bowel syndrome and diarrhea - very effective drug.

The second drug approved by the FDA in about 2001-02 was tegaserod or Zelnorm and has been very effective in the management of patients particularly in with IBS and constipation and with bloating and gas. Unfortunately, just this last weekend, the FDA suspended this drug because of concerns of cardiovascular and coronary events in a small group of patients in clinical trials. Currently this drug is suspended and unavailable, that was mainly used for constipation.

We can, of course, treat constipation with other compounds currently available over-the-counter, such as maybe Sena compounds, lachlose, Milk of Magnesia; or GlycoLax and MiraLax, which are Pec compounds, which can help. But it's the pain component that remains bothersome, and for that we may have to resort to using low doses of antidepressants - not because these people are depressed but we have found that low doses of antidepressants have specific effects in the gut-brain connections.

We believe that a major dysfunction in the body in IBS patients is really how the brain and the gut or the gut and the brain talk to each other. It is the neurological connection between the gut and the brain that is dysfunction, so these low-dose antidepressants tend to improve this dysfunction, tend to reduce the pain sensations that are going to the brain, and thereby help this patient.

If left untreated, what affect will IBS have on a person?

I think the problem is that if you don't treat patients adequately, or they're not well diagnosed, they continue to develop a chronic pain syndrome. Many of them, unfortunately, get on to opiates, narcotic drugs, or resort to other means of inadequately or incorrectly treating them, and they get into vicious pain symptom cycle and lead to disability and dysfunction in the society.

  think it's very important that these patients are attended to. The main difficulty we have is, let's say you have heartburn or reflux disease, you can actually scope the patient, put an endoscope down and identify that they have ulcers in their food pipe and they you say, OK you have acid coming back up and causing inflammation.

In IBS we don't have any single good test that can help to diagnosis this patient. So many times they're not well-treated and these patients go around to multiple physicians trying to seek help. It is important that they should be treated adequately; we have drugs available, we have diagnostic studies that can help us, we've got symptom criteria that can help us. So if you don't treat these folks, I think the condition becomes chronic and becomes more refractory to treatment. That's the problem.

Is UI Hospitals and Clinics involved in any studies with regard to IBS?

We have a number of studies going on at UI Hospitals and Clinics in patients with constipation; we have studies in patients with fructose intolerance or the fruit intolerance, which I said can lead to IBS symptoms. So these are some of the studies, many of them we have pioneered and we have initiated those studies. Yes, we have studies ongoing in the evaluation and treatment of patients with IBS.

KXIC broadcasts are presented in mp3 format. The latest version of Windows Media Player, QuickTime Player, or Real Player is required to play them.

Listen to the radio broadcast