Discrepancy in Defining Secondary-Progressive Multiple Sclerosis

Peter L. Salgo, MD: I feel your pain, with just 1 diagnosis code. You’re relying on clinicians to speak to this. And is there a generalized agreement? Do all payers, and all providers, follow common criteria for SPMS [secondary-progressive multiple sclerosis] diagnosis? Help her out.

Maria Lopes, MD, MS: I’d like to start actually by trying to understand. What are the criteria? Is there a consensus?

Peter L. Salgo, MD: That is what I was going for. Go ahead.

Patricia K. Coyle, MD, FAAN, FANA: It’s very interesting. No, there is no absolutely agreed-on consensus for SPMS. A global MS [multiple sclerosis]—based registry reported in a recent article, they looked at several dozen different definitions for secondary-progressive MS, and they came up with what they felt was the most reliable. It will never be used in the United States. It was EDSS [Kurtzke Expanded Disability Status Scale] based, and most people in the US don’t use the EDSS in their MS cohort.

I think you’re looking at a relapsing patient for whom you have documented gradual worsening independent of clinical attacks going on for at least 6 months, probably at the right age you know they are at risk. And an astute patient will realize they’re entering secondary-progressive stage before the physician can pick it up, in my experience.

Peter L. Salgo, MD: They know it. They can tell.

Patricia K. Coyle, MD, FAAN, FANA: They know it because they’re slowly losing function. It’s a gradual thing.

Thomas P. Leist, MD, PhD: One important thing is that very often in the evaluation of MS patients, our examinations or what’s reported is qualitative. The patient is evaluated. The strength looks about right. The gait looks about right. We do not do a lot of quantitative assessment.

Patricia K. Coyle, MD, FAAN, FANA: Absolutely.

Thomas P. Leist, MD, PhD: The 25-foot walk at every visit, the 6-minute walk. Obviously, that’s not possible from a time point of view, so the quantification of the tests. And secondary-progressive MS becomes very much an opinion piece, because we don’t have the underlying metrics. But I think the important part is also that—and I’ll come back to this—we don’t have a biology at this point. And we don’t have a biological marker to say, “This is up.” Therefore, you have secondary progressive.

Patricia K. Coyle, MD, FAAN, FANA: This is a very good point because there was a recent article from the UC San Francisco database in Annals of Neurology talking about silent progression. What they realized was that the deterioration was so subtle, they weren’t typically picking it up. This is because of the lack of quantification.

Peter L. Salgo, MD: All right, so this is a quagmire for you.

Maria Lopes, MD, MS: Absolutely.

Peter L. Salgo, MD: You have actually made me feel your pain.

Maria Lopes, MD, MS: That’s a unique moment.

Peter L. Salgo, MD: A unique moment, and we go back a long way. Here’s a disease, which is terrible, which has all the acronyms, all of which have different end points if you will. And you’re asking her to help you pay for treatments. And we’re going to discuss these treatments, which aren’t cheap, but you’re not giving her specific biomarkers. You’re not giving her specific exam findings. What percentage of patients are diagnosed with SPMS anyway?

Patricia K. Coyle, MD, FAAN, FANA: If you look at the old days before treatment, they talked about 50% of relapsing patients within 10 to 15 years became secondary progressive. In the modern era, that’s way down. It’s way less than 20%, way less than 20%.

Peter L. Salgo, MD: There’s another 1 that comes up: active SPMS, nonactive SPMS. What the heck is that all about? I’m getting really confused.

Patricia K. Coyle, MD, FAAN, FANA: Well, Tom had addressed it.

Thomas P. Leist, MD, PhD: The FDA has given it to you, in terms of who we used to call active-secondary progressive as part of the relapsing forms of multiple sclerosis. Evidence of new MRI [magnetic resonance imaging] lesions, evidence of attacks—that qualifies it.

Patricia K. Coyle, MD, FAAN, FANA: Over a defined time frame.

Thomas P. Leist, MD, PhD: Over a defined time frame.

Peter L. Salgo, MD: But is this a distinction without a difference? Is SPMS treated today different from RRMS?

Patricia K. Coyle, MD, FAAN, FANA: The issue is previously if the secondary-progressive MS patient was considered to have a relapsing form, they qualified for relapsing MS therapies. It’s been a little controversial. They would be treated if they had a superimposed clinical attack or contrast lesions, or new lesions, etc.