Unique Challenges of DME Treatment

TranscriptEhsan Rahimy, MD: Next, we’ll be switching to diabetic macular edema [DME]. Ali, what are some of the unique challenges associated with the treatment and management of DME that we don’t typically encounter when dealing with our patients with macular degeneration?

Ali Khan, MD, FACS, FASRS: I think Veeral, Jon, and yourself brought this up, but the type of patient who’s coming in for DME is very different than the type of patient coming in for AMD [age-related macular degeneration]. [They are] typically younger, working-aged patients who perhaps are more likely to be lost to follow-up or be noncompliant with treatment intervals simply because they are not able to come in or are caretakers for other people. There have been quite a few studies that have been published now looking at risk factors for noncompliance or being lost to follow-up. Younger age and needing to work have often been cited for the diabetic population in general.

To that point, phase 3 clinical trial data are based on a very specific diabetic patient, where perhaps the A1C [glycated hemoglobin] criteria for entry, or visual criteria for entry, is just not what we see in the real world. So extrapolating the data, particularly when you have a systemic marker of a disease, such as the hemoglobin A1C, which we don’t have for neovascular AMD, I think that changes the equation a bit.

Then, who actually needs treatment and when, is up for debate. There’s DRCR [Diabetic Retinopathy Clinical Research] Network Protocol V, which showed that patients with diabetic macular edema and good vision could wait. That’s not true of our protocol with neovascular AMD, where we usually treat right away. There are more gray areas with diabetic macular edema than there are with neovascular AMD. Luckily we have the DRCR Network and other large consortiums that are trying to work out these gray area type of questions. But I do think that the DME population is quite distinct from AMD.

Jonathan Jonisch, MD: I think also when you risk-stratify right when they walk in the door when you see them, there are different risk factors that you could identify between the different diseases. In AMD we know their beginning vision is going to predict their end vision, the size of the CNV [choroidal neovascularization], all these things are predictive. In DME, [we ask] what’s their A1C control, how’s their foveal avascular zone, and what is their diabetic retinopathy severity? So you kind of have different risk stratifications to try to predict who’s going to do well and who’s not. I think that’s helpful to have certain parameters from the beginning to educate them on what their prognosis is.

Ehsan Rahimy, MD: Do you find that your compliance with visits is less with the diabetic patients over time?

Jonathan Jonisch, MD: I think they’re different. Obviously, we know there have been data. They have so many doctor appointments, they’re working class, they have a lot of headwinds in front of them that would lead to noncompliance. Life gets in the way more for them than then our retirees. Many of our AMD populations are obviously elderly and retired. You could make an argument depending on the severity, probably also depending on your geography. The severity and how often they have to be in the clinic, I would say on average my patients with AMD probably have to be treated more frequently overall than some of the diabetics, chronically. So there is give and take. I think when we look as a whole, our patients can be more compliant. But it still surprises me when we look at the data about how compliant our patients are with their anti-VEGF regimens.

Ehsan Rahimy, MD: We spoke earlier about treat-and-extend intervals. Are you capping your DME treatments at 4 months as well too? Do you guys tend to go a little longer?

Veeral Sheth, MD, MBA, FASRS, FACS: I’ve gone longer, and I’ve done more PRN [as needed dosing] with DME as well. Again, I think it’s a balance between getting enough patient buy-in. I think the problem in DME is that you’ll get patients who have 20/20 [vision], you’ll want to treat them, but you just know there’s only so much I can push before the patient says, “What’s the point of this?” I think it’s a different approach altogether than with our patients with neovascular AMD. And I think its much more likely, for me at least, to extend it further out. You’ve also got other therapeutic options for these patients as well. So that’s another consideration, whether it’s long-acting steroids, laser, or [another treatment]. And if the patient starts getting worse, a lot of times you can get them in and bring them back, unlike with the patients with neovascular AMD, when it comes to vision. I think there’s more nuance there, but yes, I’m much more likely to go to PRN or extended intervals more so than with the patients with AMD.

Ehsan Rahimy, MD: Jon mentioned something really interesting earlier about, even though we know from a host of studies that diabetics have a higher rate of noncompliance with visits, we’re still overall very impressed at just how many of them stick with their injections. And it’s informative to compare that to our diabetic population that doesn’t get injections. I don’t know what you guys feel about this, but I think there’s something psychologically motivating about having to go to [the] doctor’s appointment and get that shot. They are proactively doing something for me, it’s almost like, my analogy is, it’s going to the dentist for your cleanings, you just show up to do it. Whereas if it’s one of those quick visits [when you are told] you look fine, come back in 6 months or a year, those are the patients who disappear in my experience. I don’t know what you guys feel.

Jonathan Jonisch, MD: It’s been looked at throughout medicine, and this has come up with our drugs that are going to be more durable. I think most of us extrapolate that into saying, [a] lower treatment burden is going to raise compliance. And it’s been looked at throughout medicine, if you ask a patient, “Take your blood pressure medicine Monday, Wednesday, Friday,” and then you do another group, and you say, “Take your blood pressure medicine every day.” It’s been shown over and over that the patients who have to do it every day, they’re much more compliant, because if it’s not part of your daily routine, the compliance goes down. It’s been shown with glaucoma drops as well. When you start going to every other day or twice a week, patients are more…. So the question is, is a patient who’s coming in every 2 months going to be more or less compliant than somebody who’s going to come in every 4 months? It’s kind of an interesting debate that we haven’t seen yet in our field. I think most of us are saying [that with a] lower treatment burden, hopefully, they’ll be more compliant with those visits. But I think those are related conversations.

Transcript edited for clarity.