Millie Long, MD, on Defining Disease Severity in Ulcerative Colitis

Dr Millie Long discusses the difference between the "snapshot" of disease activity and the "movie" of disease severity, and the importance of carefully assessing severity when choosing therapies and developing monitoring strategies for patients with ulcerative colitis.

Millie Long, MD, is a professor of medicine, vice chief of education, and director of the fellowship program in the Division of Gastroenterology and Hepatology at the University of North Carolina at Chapel Hill.

Hi, this is Millie Long from Advances in IBD here at the national meeting and what a meeting it has been. I wanted to recap a little on a talk I did on the first day of the meeting where we tried to set the stage for treatment of ulcerative colitis, meaning how do you select the patients who need specific advanced therapies? And the way we recommend doing that is based on disease severity.

So what I really tried to do is differentiate disease activity, which is more of a snapshot, a photograph, let's say, of how a patient is symptom wise. Are they having bleeding? Are they having urgency? Are they having bowel movement frequency? As compared to disease severity, which actually is more of the movie. It's more of a longitudinal view of the patient, not only factors like the symptoms I mentioned, but endoscopic severity, how severe that inflammation is potentially using something like the Mayo score, where if they truly have a Mayo 2 or a Mayo 3, that's more severe disease.

Also other factors, things that are risk stratifying. So younger age, male sex, the fact that they perhaps may have a low albumin or a very high CRP, these are markers of more severe disease. Other factors that really kind of define disease severity were actually developed by my colleague, Corey Siegel, as part of something called a disease severity index. And in this index, they got together a group of expert gastroenterologists who kind of helped to provide weights on which factors really lean towards a more severe patient. You can probably imagine that the highest rated factor was the endoscopic severity. That really weighs heavily on the severity index. And in fact, in my practice, a Mayo 3 endoscopically, that's someone who needs to be on an advanced therapy. This is no longer a mesalamine patient. The other factor included use of corticosteroids. Once someone needs corticosteroids, they're really at a higher level of disease severity and that weighs in their disease severity definition.

Other factors need to be taken into consideration, because of the longitudinal nature of the disease, meaning prior therapies that they have failed, if they've previously been on a biologic that's obviously a much more severe patient. Those types of factors weigh into our decision making. So again, using that movie, that version of disease severity that could include biomarkers, endoscopy, certainly clinical symptoms, but also these factors like the need for steroids, these factors like young age at onset, the fact that they have quite severe endoscopic disease, those factors mean a patient should actually be initiated on advanced therapy immediately at diagnosis.

And so one of the other pushes of this meeting has really been the role of early diagnosis and early appropriate therapy. We obviously have great data now in Crohn's disease, which you've heard about from my colleagues where earlier treatment potentially improves outcomes to a much greater extent than a step-up approach. We truly feel that the same is true in ulcerative colitis, that traditionally we think of disease progression in Crohn's disease, but that ulcerative colitis can also progress. So the idea of appropriate initial therapy and a monitoring strategy.

One of the other things I spoke about was utilizing treat to target to really assess your patients and ensure that not only are their symptoms doing better, but are they endoscopically healed on the inside? Is their calprotectin improved? Or even a new novel therapy or novel assessment tool, which is intestinal ultrasound. This is something that I've actually started to use in my practice and that bowel wall thickness, that you can get point of care right at the time of your clinic assessment, helps you to understand A, if there's inflammation present, and B, if it has improved associated with the therapy that you select. So I think the take home messages are really use all of the factors that you need to define a patient's disease severity.

Again, heavily weighted by endoscopic severity and also by the use of corticosteroids, really being markers for that more severe patient scenario. Select the appropriate treatment, initiate it early, hopefully help to prevent progressive complications from disease. And then once you initiate the therapy, whichever therapy you choose, you want to monitor and ensure that the patient has had an appropriate response both clinically, so symptomatology is improved, but also kind of biologically from an inflammation perspective with fecal calprotectin, for example, and endoscopically with mucosal healing. At this point, we're not really using histologic healing as a target, but really that healing of the mucosa via that endoscopic scale that we refer to called the Mayo score.

So hopefully those pearls have been helpful. Setting the stage, you're selecting your treatment based on other criteria, but this is how you define a patient with moderate to severe disease and really better understand disease severity and its role in choosing therapies.