Epidemiology of IBS
 

Lawrence Schiller MD: IBS is a very common problem in the United States. Surveys have shown anywhere from 10 to 20% of the population meets criteria for a diagnosis of IBS.

Peter Salgo MD: Joe, have these rates stayed constant over time or is this a changing target?

Joseph Sweeting MD: No, the rates, I think, stay about the same. What seems to happen is that people drift out of that category, and new ones drift in. So while the prevalence remains pretty much the same, it's not always the same people.

Peter Salgo MD: How does the United States compare to the world? Is the rate the same elsewhere?

Lawrence Schiller MD: Overall, it's pretty similar in western Europe, but it ranges widely elsewhere. As many as 25% of people in the Far East have IBS.

Peter Salgo MD: This brings up a key question. Why is there a difference? I heard it's 4% in Singapore, for example, and, what, 30% in Nigeria.

Lawrence Schiller MD: It's hard to say. Probably cultural and dietary factors play a role, but there's a lot we don't know.

Peter Salgo MD: Joe, why don't you break it down a little bit? How do we assess this by race and by gender, by age?

Joseph Sweeting MD: There's an obvious gender difference. I think in all the studies around the world - well, possibly with one or two exceptions - there have been far more women with the problem than men. Roughly two-thirds of the patients are women. That's certainly the case in the United States and in western Europe; it may not be the case in places like India. There's some data from India that's a little hard to evaluate where it looks as though more men at least come to doctors with this problem than women do. But how much of that is a cultural thing, and how much really represents difference in the incidence of the disease, is not clear.

Peter Salgo MD: Let me ask this question and, of course, you're both allowed to say, "I don't know." Why more women than men, Larry?

Lawrence Schiller MD: I don't know.

Peter Salgo MD: Joe?

Peter Salgo MD: Well, at least we're both honest on this. Compared to other chronic diseases, though, how does IBS impact the quality of life on people who suffer from that? Larry?

Lawrence Schiller MD: It can be surprisingly severe. Most people think of IBS as a relatively modest problem, where patients have some abnormalities of their bowel functions and pain, but they don't think of it as being a big difficulty. However, if you actually look and see, it has a tremendous impact on people's productivity at work, on their happiness at home and many other facets.

Peter Salgo MD: What percent of all physician visits to primary care physicians can really be put into the category of IBS, Joe?

Joseph Sweeting MD: It looks like that's somewhere in the range of 12 to 15%; it's a very significant figure.

Peter Salgo MD: That's huge. I mean, that's much larger than I, as a non-GI specialist, would have expected.

Joseph Sweeting MD: Right, and if you look at the percentage of IBS patients who come to see gastroenterologists, it jumps up to approximately 25%.

Peter Salgo MD: That I might have expected. I mean, after all, that's your guys' - you'll pardon the expression - bread and butter. But why is it that large a problem? Any ideas here?

Lawrence Schiller MD: It really does impact on people's quality of life. They don't like that and they want some help with it.

Peter Salgo MD: In this age, where we're trying to be budget-conscious, when you hear numbers as large as the numbers are that you just presented, the next question is: What's the cost of this disease, both direct and indirect? Larry, do you have any figures?

Lawrence Schiller MD: If you add up all the direct and indirect costs - lost time and productivity - it's about $30 billion a year (in the USA).

Peter Salgo MD: That's simply staggering. Joe, are patients with IBS more likely to have abdominal surgery, for example, which is going to add to the bill?

Joseph Sweeting MD: Yes, that's a fact that gets a little lost in the discussion sometimes. The number of abdominal surgeries that IBS patients have is about three times the average. Since they're mostly in women, hysterectomies figure very prominently, as do cholecystectomies.

Peter Salgo MD: Let me focus on that for just a minute, because I'm hearing a disturbing trend in this answer. Is it that they're having unnecessary surgeries or misdiagnosis leading to surgery? Physicians are missing the diagnosis of irritable bowel?

Joseph Sweeting MD: That's a hard question to answer. I don't think that they're necessarily wrong, but one of the interesting things about IBS patients is that there are two main groups, at least in this country. There are the people with IBS who come to doctors, and there's the group of IBS patients who don't. It's the group who come to doctors that have this high incidence of surgery and other problems. The group that never come to doctors, actually the majority of IBS patients, as determined by household surveys, have the same symptoms and are just as miserable.

Peter Salgo MD: But they haven't had surgery.

Joseph Sweeting MD: They haven't had surgery, and they haven't come to the doctors about it.

Lawrence Schiller MD: I think the point is that people with IBS have pain as their main symptom. If you have chronic abdominal pain and it concerns you, you'll keep going around to doctors until something is done.

Peter Salgo MD: You'll doctor-shop.

Lawrence Schiller MD: And often, it ends up with surgery.

Peter Salgo MD: Perhaps one way to look at this is work productivity and the loss in productivity in America. So, can you get a handle on that, Larry?

Lawrence Schiller MD: If you calculate the figures, again, about $10 billion of that $30 billion cost is lost productivity.

Peter Salgo MD: That's simply enormous. So if I understand both of you correctly, we're dealing with a syndrome here that is relatively under-recognized in the medical community and is one of the major problems of people in America today. Is that a fair statement, Larry?

Lawrence Schiller MD: I think it is, yes.

Peter Salgo MD: Joe?

Joseph Sweeting MD: I agree completely, and I think your choice of the term "unrecognized" is a good one, because IBS doesn't get the focus that it should. It leads to lost time at work, lost time at school, these added costs of surgery and so forth.

Peter Salgo MD: I have some numbers here, just confirm them. I heard 30% of patients with IBS miss workdays. And 12% have actually been fired from their jobs, because of loss in productivity associated with IBS. Are these numbers accurate?

Lawrence Schiller MD: They are. The patients often have to leave work or change their work patterns so that they can work at home.

Peter Salgo MD: That's astounding. I mean, is it shocking to you two as gastroenterologists as it is to me?

Joseph Sweeting MD: Well, it's so common. We hear that story over and over again, "I can't go to work," or "I can't do this, I can't do that,. Perhaps we get a little bit jaded hearing that. But we recognize that one of the major problems associated with this disease is that it really does impact on people's lives and on the general economy.