Dr Brian Lacy and Dr Douglas Drossman Discuss Disorders of Gut-Brain Interaction

Drs Lacy and Drossman review the definition of disorders of gut-brain interaction, several common types of DGBIs, and treatment for these disorders.

Transcript:

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Any views and opinions expressed are those of the authors and or participants and do not necessarily reflect the views, policy, or position of the Gastroenterology Learning Network or HMP Global, its employees, and affiliates.

Dr Brian Lacy:

Welcome to Gut Check, a podcast from the Gastroenterology Learning Network. My name is Brian Lacy. I'm a professor of medicine at the Mayo Clinic in Jacksonville, Florida. I'm delighted to be speaking today with Dr Douglas Drossman, Professor Emeritus of Medicine and Psychiatry at the University of North Carolina in Chapel Hill, and founder, president emeritus, and chief executive officer of the Rome Foundation. Dr Drossman has been a driving force behind the Rome Foundation and the Rome criteria for the past 30 years.

As many of our listeners know, Dr Grossman is an expert in the field of functional bowel disorders, now called disorders of gut brain interaction. He has authored hundreds of peer reviewed publications, most of which have focused on disorders of gut brain interaction. He has lectured extensively throughout the world on these common disorders. Finally, Doug is a strong advocate of the value of good communication skills to improve the patient provider relationship. He has set up highly successful training programs to teach providers how to optimize their care with patients.

Dr Drossman, welcome. What a delight to have you here today. Let's begin simply. What are disorders of gut brain interaction, which we may refer to in our talk today, as DGBIs?

Dr Douglas Drossman:

Thanks for having me, Brian. I'm glad to be here, and I think that's a good first question. Instead of us now using functional GI disorders, the problem there is it implies uncertainty or that the problem is psychiatric. This is the way the term functional often comes across. So, we now use disorders of gut brain interaction since Rome 4, because it's a more scientific way of approaching DGBI.

It's a disruption in the brain gut connection. And this can lead to these symptoms like abdominal pain, dyspepsia, and bowel issues. If I could just give as an example about the brain gut axis and why we do that. Looking at GI pain, pain signals travel down from the gut to the brain, then the brain uses the gate control system to send signals back down through the spinal cord to modify or even block the pain. That's the gate control theory.

But when this system is dysregulated because of anxiety or depression, or even when the pain is constant, the brain cells kind of wear out. And as a result, the brain can't down regulate the pain as effectively the pain gets worse. That's why we get a DGBI and with our own classification system, we now have over 50 adult and pediatric DGBIs each with their own criteria.

Dr Lacy:

Great background for our discussions today. So how common are these disorders of gut brain interaction?

Dr Drossman:

Oh, they're really common. I think the good thing is that Ami Sperber, who's on with the Rome Foundation completed an international survey of over 70,000 subjects in 33 countries. The data across countries is pretty specific. With that database, we found that about 40% of the general population have at least 1 DGBI.

It's about one third more common in women. These disorders may get less common as people get older. And then some of the more common diagnoses would be constipation functional constipation at about 12%, dyspepsia at about 7%, functional diarrhea about 5%, and IBS at about 4%.

Dr Lacy:

Wow! 40%! That's a lot of people!

One reason why we're chatting today because these disorders are so prevalent. You mentioned there are over 50 adult and pediatric disorders of gut brain interaction—are these disorders related or interrelated, or do they just exist as a singular diagnosis?

Dr Drossman:

Yeah. There's overlap. And think of it physiologically, I believe it relates to the central mechanism for surveying incoming visceral data. If the mechanism is not working right, the threshold drops, and you get more signals, and you get more symptoms, not only GI. In fact, in Ami's study, she found that 40% had had 1 DGBI as we mentioned, but 68% had another diagnosis of that group of 40%. 22 had 2 diagnoses, and 7 had 3 diagnoses.

So we know that as these disorders overlap more, we're seeing more severe symptoms. We're seeing more comorbidities and poor quality of life. I think it's a reflection of the brain's filtering mechanism.

Dr Lacy:

So it really shouldn't surprise providers that they may encounter patients not with just 1 DGBI, but a second or even a third, and their quality of life will be more severely impaired.

Dr Drossman:

Yeah. And as a clinician, you know, what's it like when you see someone coming in with 3 or 4 or even 5 diagnoses, you know, there's a lot going on there in terms of how they're doing.

Dr Lacy:

Absolutely. And I think we're going to circle back to that because I think sometimes that can be overwhelming for providers, but I think we will learn some tricks today about how to deal with that. So, Doug, how do these disorders of gut brain interaction develop?

Dr Drossman:

It's a complex thing is to talk about the biopsychosocial model, which is something I've been involved with, since my training with George Engel, I don't know, 50, 60 years ago, he talks about the interaction of biologic, psychological, and social systems that maintain a balance in the body or homeostasis. And when there's an imbalance in any system, it can affect the other systems, and it can relate to biologic factors.

When we talk about disruption, mucosal immune dysfunction or the microbiome Or certain foods that could be you could be sensitive to, like gluten, or psychosocial factors, like anxiety, a history of trauma. And these can influence the brain's regulation of this axis, this brain gut axis. And when they're persistent and significant enough, that's when you get the disorder. It's an imbalance in those systems.

Dr Lacy:

Maybe it wouldn't surprise us then too if somebody's in a pretty stable course, if there's some new environmental influence or a new stomach flu or medication drive change, it might perturb that system as well. Right?

Dr Drossman:

Exactly. And how you deal with it depends on what the other factors are. If you have an infection and you have psychological distress, you are more likely to have an IBS, than when you don’t have psychological distress. They all interact.

Dr Lacy:

They just layer on, don't they?

And so thinking about these risk factors you mentioned for developing gut brain interaction. Are there some groups we should identify? For example, are women much more likely than men to develop a DGBI? Are younger patients more likely than older patient?

Dr Drossman:

Sure. I mean, I mentioned with the epidemiologic study that women were 3 times more likely to develop a DGBI. There is a slight family influence, but it's very hard to sort out what's genetic and what's relates to early family modeling of the illness as a child. We learned from Rona Levy and other investigators that early parental modeling around illness, whether you take the child to the doctor or attend to it more, is more likely to lead to more likely going to doctors later in life and having these symptoms.

Then we know that trauma and other stressful experiences can influence the development and severity of IBS too. We know the microbiome, when there's a greater prevalence of the so-called bad bacteria, or less diversity in the types of bacteria. That's more likely to lead to a DGBI.

An infection and a stressful environment, as I mentioned, can develop post infection influence. Dietary factors, high FODMAP foods and those susceptible with high sensation threshold, and the food the FODMAPs will lead to gas and distension, and that will trigger symptoms.

With women, menstrual symptoms can start or worsen IBS symptoms. They get more cramping and diarrhea in the perimenstrual period. And then we see these comorbidities like fibromyalgia, interstitial cystitis, POTS, pelvic floor disorders. They're seen more commonly in people with IBS, and their association makes their ideas symptoms worse.

Dr Lacy:

Such a nice overview about the pathophysiology. So clearly, it's not just 1 single pathophysiologic event that causes a DGBI to develop in all patients, but rather immune dysfunction in some, a prior infection, environmental stress, other coexisting diseases. It's a whole myriad of things, isn't it?

Dr Drossman:

That's the challenge for the neurogastroenterologists. You have to look at all these factors and see which what's the interaction of these factors and which are more dominant because that’s going to affect treatment.

Dr Lacy:

Taking that history, trying to identify, I call them insults. These insults to the GI tract, to the body, to the brain, can take some time, but it is really pays off. Don't you think?

Dr Drossman:

Yep. Absolutely.

Dr Lacy:

As you've already mentioned, lots of different pathophysiologic events and lots of different types of disorders of gut brain interaction. Is there a single symptom or a set of symptoms that seems to characterize all of these disorders?

Dr Drossman:

No. I think with DGBI, you're looking at the dysregulation of GI symptoms. One of the most dominant symptoms that we often consider is pain, bloating and pain and sensory disturbances. But there are also motor disturbances like diarrhea and constipation, vomiting. So I think, there are interactions about GI functioning that are being dysregulated at the level of the brain.

Dr Lacy:

So Doug, you've already mentioned the prevalence of these very common disorders and the symptoms, but what about the impact on patients? What's really the impact on patients and the impact on the healthcare system of these very common disorder?

Dr Drossman:

For patients with DGBI, you can range from subthreshold symptoms, you know, having a bad day because of diarrhea or cramping, to meeting criteria for diagnosis and even having severe diagnosis and poor quality of life. So we have some patients who continue to function normally, where others—the ones we see as neurogastroenterologists—have a have a major decline in their well-being. And I think this relates to resiliency. I think the ability to adapt, recover, and maintain well-being in the face of these symptoms and stress, some resiliency is innate. Some of us naturally are more resilient, but it also can be learned.

This is where the treatments like brain gut behavioral therapies can enhance resilience by reducing maladaptive thinking and help the patient regain control. My area of interest with neuromodulators can raise symptom thresholds, reduce and that can reduce the emotional distress and enhance mental capabilities, even to help the patient do the work of therapy.

Now for health care, it's really complicated. I think when we're dealing with DGBI and other nonstructural disorders like fibromyalgia, chronic pain, there are no structural abnormalities. In our health care system, because of the dualistic model, they're considered second class or not real.

When providers don't understand it's reality or how to diagnose it and even to treat it, they rely on more tests. They view the patients as psychiatric, and then this leads to unnecessary expenditures in health care costs, treatment failure, patient dissatisfactions, and the providers may exhaust these health care resources searching for the correct diagnosis. When in reality, I think the diagnosis using wrong criteria and treatments are readily available. So I think we need to educate the health care providers, how to communicate and connect better with their patients, and, ultimately, I think this will reduce the burden on the health care just to you know, there's been a significant area of my work.

Dr Lacy:

Absolutely. I think there's one estimate that we spend about $20,000,000,000 a year just diagnosing and treating patients with irritable bowel syndrome, and you're right. You know, that 5th CAT scan is unlikely to show much of anything, and it increases health care costs and makes patients worried, and even exposes them to radiation. Right?

Dr Drossman:

Yeah. You have to believe that this is a real disorder, and you won't see anything structurally. So stop the ordering of tests. Accept what they have, and then work with that.

Dr Lacy:

So, Doug, with these prevalent disorders, what's the natural history of these disorders of gut brain interaction, do they just eventually resolve on their own or do they always require treatment? And another question that comes up from patients is—do these increase the risk of something more serious like colorectal cancer or inflammatory bowel disease?

Dr Drossman:

Yeah. I mean, I think that that there's variability, as I said before. Perhaps one of the best kinds of getting ways of getting Yes, for example, if you're an adult who gets post infection IBS, those are people who eventually do well and many actually recover because they don't have the prodrome of enabling comorbidities going on. But those with lifelong symptoms that begin in childhood and who have psychological comorbidities and who tend to retain their symptoms, and those are the patients who are much more severe, with poor quality of life.

Then there's the middle ground that we often see, where symptoms wax and wane. And what we're doing is we're treating them with baseline medications. Things get worse. We reassess the situation, not necessarily getting tests, but reassess how they're doing, modify their medications. So, you know, you need an early diagnosis. You need to get good natural history of the disorder going back to childhood to try to get a profile of what the nature of the intervening factors are.

And I think it's accomplished by engaging with the patient in a patient-centered care model and giving proper treatments as I know we're not talking about that today. But in general, there are dietary approaches, neuromodulators, peripheral neuromodulators like treating diarrhea and constipation and pain and the brain gut behavioral treatments, and central neuromodulators like antidepressants.

To your last point, there's no evidence that a DGBI increases the risk for cancer or inflammatory bowel disease. The problem is making sure you don't have it, so you may want to exclude that diagnosis. And then when you made the diagnosis, there's no evidence that it's more susceptible to getting these conditions, but they're not immune to getting them.

You have to always keep an open eye if things change. They lose a lot of weight, or they get, blood in the stool. Then you must reevaluate the situation.

Dr Lacy:

And doing what you do so well, a lot of this is that conversation with the provider and the patient confidently making that diagnosis using clear words, clear language, educating the patient, reassuring them, and then really getting them on a treatment plan, while sometimes minimizing tests. Right?

Dr Drossman:

Right.

Dr Lacy:

Yeah. I also want to speak to that too because, you know, we're speaking in generalities about these DGBIs, disorders of gut brain interaction, there are so many. But just to clarify what you said a little bit, you know, let's think about either IBS, or chronic constipation—is there a single test that we need to order for every patient that will just make that diagnosis? Do we have a biomarker? Does everybody need a colonoscopy and a CAT scan? Or should this be more of an individualized approach?

Dr Drossman:

Well, yes. I think, of course, there are guidelines that go beyond DGI. You know, if you're over 45 or 50, depending on the recommendation, you would do a colonoscopy to be in that patient. There are general guidelines to look for celiac disease if they have diarrhea.

But in general, it's a more individualized approach. I mean, you and I, along with other neurogastroenterologists in the field, have made significant strides in addressing the diagnosis through the Rome Foundation, which provides clear guidelines. So you do your basic screening studies, which are straightforward, not too expensive unless you need a colonoscopy. And then you you make the guidelines.

If there's significant weight loss and a lot of pain, you might do a CT. But in general, you make the diagnosis of IBS after you exclude those, and you treat, and you follow. And I think this knowledge, the data are that once the diagnosis is made, the likelihood of another disorder coming is relatively small. And when it does come, you know it because there are other factors, that come up that make you may want to pursue other diagnostic tests.

And my foundation, Drosselman Care, works with the Rome Foundation to provide educational resources and publications and videos to teach communication skills because when you have a good engagement with the patient, you're not having the patient say, “Doc, my pain's not better. What are you gonna do for me now? I want another CT scan.” We can talk about the symptoms in their management.

Dr Lacy:

Doug, so many amazing teaching pearls there because what oftentimes comes up is, do we have that great biomarker? If I just had that one single biomarker test to confidently make that diagnosis, but what you've just told us is take a great history—do that careful exam which reassures the patient, limited testing that's appropriate, confidently make that diagnosis, and initiate therapy, and use the Rome criteria because that combination of things probably is the best biomarker.

Dr Drossman:

That's right. Yeah. That is exactly right.

Dr Lacy:

So for our listeners, as we wind down here, we've just encapsulated 30 years And hundreds of research articles into a 20 minute conversation, talking about disorders of gut brain interaction, these incredibly prevalent disorders. And Doug, as you and I already discussed, we're gonna leave treatment of this of these disorders for another conversation. But before we sign off, do you have any last thoughts for our listeners?

Dr Drossman:

Yes, if I could make a mini advertisement for anyone interested in learning about these disorders, I published along with my coauthor, Johanna Ruddy, who, as many of you know, in her patient advocacy. She was a patient of mine, and through our relationship, we learned a lot about collaborative patient centered care. We published 3 books. The first book is about these DGBIs and how to communicate better. The second book is about my patients and how they got better through their narrative. And the third book that just came out is about many providers and what they learned.

If you're interested, there's a there's a website, www.gutfeelings.org, And you'll see about these books if you want to look into that and learn more.

The last thing I want to say is caring for patients with DGBI can be highly gratifying when you understand and believe in these disorders, can make an accurate diagnosis and established patient collaborative care.

Dr Lacy:

Absolutely. It should not be viewed of as a challenge, but rather journey to help so many, many people. So I like what you said about education, and certainly, we're talking today on gut check. So, gut feelings is an easy thing to remember. So Doug, again, thank you so very much!

To our listeners on Apple and Spotify and other streaming networks. I'm Brian Lacy, a professor of medicine at Mayo Clinic in Jacksonville, Florida. Our guest today was Dr Douglas Grossman, Emeritus professor of medicine and psychiatry at the University of North Carolina and founder, Emeritus president, and current CEO of the Rome Foundation. I hope you found this just as enjoyable as I did.

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