Good days and bad days with MS: Prof Stephen Krieger in conversation | ECTRIMS 2026

Prof Stephen Krieger: Hi, I'm Dr Stephen Krieger. I'm an MS specialist at Mount Sinai in New York.

Dr Agne Straukiene: Hi, Stephen. It's an amazing opportunity for me to sit together at the ECTRIMS conference venue, which is the largest one I've ever seen. It's around, I don't know, 6.5, by the way, hectares, which is like nine football pitches.

Stephen: Well, it feels like that when walking from one side to the other.

Agne: And we had a video recording on the Zoom. I think it was after pandemic or in the midst of the pandemic. And if you haven't watched this episode, please do go back and review. It's the best one. We were talking about the brain reserve and unique model leaky pool, which explains a lot about your...

Stephen: There are beautiful 3D rendered images that were made just for that purpose.

Agne: And today we're having a nice opportunity to sit down together in a very close proximity. There is no screen, which is always much easier for people to understand the concept that we are going to talk about today. Today is about all self-management living with MS. And my first question, very open and easy one perhaps, when people experience fluctuation of their symptoms, what could help them to understand what is going on? Because everyone living with MS has got a great fear of progression.

Stephen: Progression or relapse or anything that invokes the disease is getting worse. So, you know, one of the principles I like to tell my patients is that we're trying to prevent relapses, which are more acute events that come on over hours or a couple of days. And we're also trying to prevent progression, which takes usually much longer, months, years, to really declare itself. So fluctuations of symptoms that come and go may not be relapse or progression. In general, when someone living with MS has a resurgence of their old symptoms, things that they're familiar with in a familiar place, coming back over a day or a few days or a week, the resurgence of old symptoms, the familiar symptoms, is much more likely to reflect what I call a resurfacing of old symptoms when their reserve is low, when their ability to compensate is somehow depleted. And I say that in distinction from a new relapse, which is a new event, typically a new lesion causing new symptoms in a new place, something acute and unfamiliar, as opposed to a resurfacing or re-worsening of things that are MS and familiar. And what I would say is that distinction is really important. Because if someone's having a new symptom, that can be neurologic urgency or emergency. We might treat that with steroids. It might require a work-up, an MRI. But a resurfacing of old symptoms usually means there's something else going on, something medical that is depleting that person's reserve. It can be anything from an infection, like a urinary tract infection, upper respiratory infection, COVID, flu, to a period of being overheated, so both from fever or from external sources of heat. Sometimes overexertion can overheat and overdrain someone. And then even more subtle things, like being incredibly stressed and having their sleep interrupted those things drain reserve and can cause this resurfacing of old symptoms. It's important that we get to the root cause. And so that's what I would tell somebody, how to advocate for themselves, to think about, am I having new symptoms that are unfamiliar? Am I having a resurgence of old symptoms that are familiar? What should the care team do to figure that out?

Agne: Yeah, totally. And these fluctuations are not dangerous. So people have to understand that having extra or intensity increased symptoms is not changing your brain cells at the biology level. I always wonder, what is going on biologically when people are fluctuating in their symptoms?

Stephen: Right. I agree with you. The fluctuations are not themselves dangerous. They can, though, be a sign that there is something medical going on, like a urinary tract infection or a viral infection that could require some management. So I tend to think of it that the brain, the nervous system, is an exquisitely sensitive arbiter of how a person is doing. It doesn't necessarily mean that the brain is being newly affected by MS. But the function of someone's brain and nervous system is the window into their health. But you're right. I don't think these fluctuations mean that there's new damage in the nervous system. I think overheating is the clearest example of what's happening on a cellular basis. So our nervous system, I always tell the people I take care of, is optimised to run at 98 degrees Fahrenheit. I don't want to misstate the centigrade Celsius. What would you say the optimal body temperature is?

Agne: I only calculate Celsius.

Stephen: So what is it?

Agne: 37.

Stephen: So for us, 98, across the pond, 37. And any deviation from that optimal temperature makes the nervous system function less efficiently. It loses efficiency. The signals do not get through as well because the machinery doesn't work as well at 38 degrees, 39 degrees, 40 degrees. So someone who has MS, their nervous system already has to work a little bit extra hard to get the signals to where they're going. And anything that makes that electrical system less efficient shows the challenge. Shows the deficit. The numbness that they usually don't experience much of gets worse because now those signals are not getting through. The vision loss that's usually compensated for after that relapse is recovered, someone gets overheated, the vision starts to blur again because now those signals are struggling to get through. It doesn't mean new damage has happened. But it does mean the source of the fever needs to be identified and perhaps treated.

Agne: Somebody experiences these fluctuations. How can we make them not to feel alone? Because it's quite a journey. You have MS, you are getting these symptoms, the majority of them they're not visible symptoms. How can we make a person not to feel alone?

Stephen: Well, I think number one is if someone understands this principle, in a sense, I think that will help make it seem less unpredictable or inexplainable. The visual metaphor of the leaky pool model that we talked about a couple of years ago on your Be Well platform is the way of picturing this, to say there are lesions under the surface and they're compensated for by this pool of reserve, lake of reserve, tank of reserve and anything that drains that tank uncovers what's lurking below. And then we have to refill the tank, bring down the fever, restore the sleep, you know, whatever the issue is that has drained that person's reserve. So I think understanding this, being able to picture that, can make people feel less alone because what they're experiencing is common and is understandable. That's the first thing. Second thing I think is to say a fluctuation in symptoms is not forever. So people feel alone I think when they feel like their path has just taken a negative turn. This is not the path taking a negative turn. This is a bump in the road, a transient fluctuation typically. And so I don't think they need to feel like all of a sudden something that they've long worried about has finally occurred. That's a very isolating feeling, helpless feeling. This doesn't have to be like that. So I would start with those two things. And then of course the most important thing to keep someone from feeling alone is to be there for them. So I think this is where it is our responsibility as care providers or leading a comprehensive team in your case to swoop in and provide the work-up and the education and treatment if necessary. So that that person neither feels alone nor is alone because you'll be there with them.

Agne: I think I always ask my patients to document and keep a diary of these symptoms because quite often whilst you're experiencing that worsening it's so difficult to understand whether this is real relapse or it's just a worsening. But keeping a record of these fluctuations and symptoms you may notice a pattern and a potential triggers. So if you kind of divide your one page into three columns, what the symptoms are, what you've done today or yesterday and any potential changes in your life that potentially brought these symptoms into your daily routine. I want to know a little bit better about how do you manage the patients and encourage them to self-manage at Mount Sinai at the service level. What do you do? Do you recruit any programmes? Do you educate them in the clinics? What is going on at your hospital?

Stephen: Yeah, it's a good question. I mean I think you've led this concept of self-management and have put a lot of procedures or protocols in place for it in your place of work. I don't think most places have that. So I don't have a platform for it. But, you know, I think there's always opportunities for MS education at any point along someone's journey. I think when someone's newly diagnosed that's probably not the moment to try to educate around all of the future things that might happen. But once someone is diagnosed they understand their own MS, the way MS behaves for them. As you said, tracking that, knowing their MS signs. I think that can be very helpful. And then have conversations like this about what are someone's symptoms as you said. I like the three column approach. What are someone's symptoms? What have they done or been doing around the time that those symptoms are happening? What might be some triggers, repeated triggers that they can look out for? And that way if someone has a little bit of worsening of that old feeling of a little trouble in the right leg, for instance. They know to say, okay, this is my old MS reminder. What's been going on? They can perhaps look back. So I think tracking things to some extent can be helpful in that regard. In our centre most of the communication happens through a portal, MyChart. Do you use MyChart?

Agne: Yeah, we started recently.

Stephen: I smile because it's both helpful and also the bane of everyone's existence in healthcare because it means communications are happening all the time. So I like to remind the people I take care of that MyChart messages feel like a text message. But they're received like an email in an inbox that you check every once in a while. I won't go so far as to call it the spam mail inbox, but it's not an instant message. So for instance, I'll look at them every day or two. Our portal advises patients that a message will be seen and responded to within 72 hours to try to set expectations. So I tell people, if something's urgent, call us. If something's routine, a MyChart message is okay. But it should always get documented somehow so that there's a record of it. The clinical team can look back on it. And then the patient can know that that message is conveyed.

Agne: So you're staying connected with your patients?

Stephen: Trying to. Me and the team I work with, so we work with a couple of wonderful nurse practitioners and a nurse who get all those messages. Medical assistants who help with the authorisations of medications and access issues. The scheduling team. The social workers who can sometimes help people who have life navigation questions that are probably best suited to answer. So for the patient, it's about knowing who are the people to respond to the various needs. And for us, it's about having those people and having them be able to respond.

Agne: Your last key message based on our conversation, what would that be?

Stephen: My last key message. I think it's important for people living with any chronic disease, but perhaps MS in particular, to be good self-advocates. To do their homework. But not feel like the burden of figuring it all out is on themselves. That is to try to understand what's happening. But then let the team meet them where they are. And be useful. One of the things I tell my patients, especially someone who comes having read everything they can and trying to figure it all out and sending their MRI reports to their favourite AI tool to try to make sense of it. That sort of thing. I encourage it up to a point. I encourage it. Because I want people to understand everything and be as empowered as they can to be self-advocates. But I encourage it and then say that I don't want someone with MS to feel like the whole burden of figuring it out and understanding it is on them. That they can unburden themselves a little bit by putting some of that burden on us. Because that's ours. To help them to navigate. So that's what I would say. Take on as much responsibility as you can as a person living with a condition. But don't feel that that responsibility or that burden is yours alone.

Agne: So beautifully said. Thank you so much for this interview and I'm very very happy to have you here.

Stephen: Thank you for having me.

Agne: Thank you.