Optimizing Treatment Strategies to Manage Inflammatory Bowel Disease - Episode 2

Incidence and Prevalence of Inflammatory Bowel Disease

August 19, 2021
Remo Panaccione, MD, FRCPC

Jessica Allegretti, MD, MPH

Edward Loftus Jr., MD

William Sandborn, MD

Effect of age, gender, racial, and socioeconomic disparities on the incidence and prevalence of inflammatory bowel disease (IBD).


Remo Panaccione, MD, FRCPC:We see a wide range of patients within our practices. Ed, when we think about those patients—as far as age, gender, racial, and even socioeconomic disparities—what role do those factors play on, say, the incidence and prevalence of IBD [irritable bowel disease], and why do we see these different types of patients?

Edward Loftus Jr., MD: The textbook description of somebody with Crohn disease is somebody in their late teens or early 20s, but it turns out that we see these diseases diagnosed in patients who are anywhere from age 2 to people in their 70s or 80s. Having said that, the median age for developing Crohn disease is the late 20s, and the median for UC [ulcerative colitis] is about 5 years later. Patients may be in their early 30s and, two-thirds of people are diagnosed before the age of 40. You see this tail that goes out, and we’ve all seen these patients who aren’t diagnosed until they’re 70 or 80. The gender breakdown is probably more prominent in cases of UC, which consistently has a 60-40 division in favor of males. That holds true for things like PSC [primary sclerosing cholangitis], which is also associated with UC.

For Crohn, it’s more 50-50, depending on the region. In Asia, there’s a sense that the onset is a little later, and it might be a condition more predominantly found in patients who are men, but that’s not a consistent finding. Historically, we thought of these conditions as occurring most often in patients who are Caucasian or, in particular, who are Jewish, but that’s a relic of the 1950s and 1960s. Now we realize that these are global diseases. We’ve all seen these studies, and we know your colleague Gil Melmed has done a lot to demonstrate the increasing incidents worldwide of these conditions. I joke that wherever there is a McDonald’s, there’s IBD. I’m not implying that there’s a direct link, but it probably does reflect a change in diet. These have become global diseases.

Remo Panaccione, MD, FRCPC:How about socioeconomic status? Do you think that still plays a role? We’ve seen that in some of the epidemiological literature and whether that’s related to, say, dietary intake and the microbiome. What is your take on that?

Edward Loftus Jr., MD: It works both ways because the socioeconomic factors might play a role with the hygiene hypothesis, or with people growing up in more sanitary environments. On the other hand, the more we know about dieting and bad diets, it can work the other way. There’s a recognition among multiple cohorts, including Bill’s group, that obesity seems to be playing a role in modifying the phenotype of IBD. There’s a sense, at least in some of the literature, that obesity is bad for UC and a little bad for Crohn—maybe not as much as in UC. That’s my own take on the literature, but there are lots of threads here and there, and they’re sometimes conflicting. It’s hard to put it all together.

Remo Panaccione, MD, FRCPC:One of the things I want to pick up on is age. Bill, you and I had this discussion almost a decade ago, when we started screening some of our patients who didn’t behave like those with Crohn disease typically do. What do you guys do in clinical practice when it comes to age and, I guess, the monogenetic causes of IBD? Because we’re talking about some epidemiology, when should our colleagues start thinking about doing that?

William Sandborn, MD: Jessica is in Boston, which is 1 of the centers for studying monogenic disorders like IBD, especially Crohn disease. But most of those kids—think of the heavy genetic loading, as I understand it—are up to 4 or 5 years of age. These patients are 1 to 4 or 5 years of age, and for 1% to 2% of those patients, you can find something, but most of those kids survived to adulthood. In principle, there’s someCrohn in your adult practices. They tend to be clustered in some of our university hospitals because they have a tough force, and patients have a long time when they’re at risk to get complications in surgery and end up with short bowel and other things. That’s largely lost on adult gastroenterologists, that a subset of their patients have onset early on and need to get screened. I’ve worked with the Children’s Hospital [of Philadelphia], and Boston Children’s Hospital, and the University of Toronto to try and treat some of these really difficult-to-manage adult patients who had onset before age 5. We found a few cases of monogenic disorders and, of course, depending on just how bad their situation is, some of those can be treated with bone marrow transplant. There are some real clinical applications.

Remo Panaccione, MD, FRCPC:Jessica, what’s your take on that? Are you guys [Brigham and Women’s Hospital] doing more testing? If I remember correctly, out of the University of Toronto—even though we think about, as Bill suggested, the early onset in that age group—almost half their cohort that they published recently actually was diagnosed between the ages of 12 and 18. Even in adolescence, Bill referred to your expertise in this area?

Jessica Allegretti, MD, MPH: It’s not my expertise, but I’m very fortunate that Scott Snapper, who runs our very early onset IBD program across the street at Boston Children’s Hospital, has done extensive work in this space. I’m very fortunate that, often, when these children transition to our care, they’ve already had full work-ups because they received their care in pediatrics at Boston Children’s Hospital. We’re aware of those situations going in, or they’ve been addressed already. Once in a while, though, you’ll meet someone—a new patient—who you find out was diagnosed quite earlier, and their condition has extremely aggressive course. Often, I’ll refer those patients for full genetic testing, just to try to understand what I’m missing, because there are some potential opportunities, as Bill mentioned, to do aggressive but very therapeutic maneuvers with some of these patients, like bone marrow transplants. I wouldn’t say we’re doing that routinely, but it has happened with some success. We have a full center that does all this work for us, so I’m very fortunate in our area.

Edward Loftus Jr., MD: As the price of these types of multigene panels or whole exam screenings continue to go down—and it’s rapidly going down; this isn’t going away—we’re going to see more of this. There are already clinical genomics service lines in different areas of our specialty. They’re going to continue to flourish.

Remo Panaccione, MD, FRCPC: Thank you for watching this HCPLive® Peer Exchange. If you enjoyed the content, please subscribe to our e-newsletters to receive upcoming Peer Exchanges and other great content right in your in-box. I’m sure you’ll see the folks in front of you on future programs. With that, thank you very much.

Transcript edited for clarity.