Ben Thrower, MD, Medical Director, Andrew C. Carlos Multiple Sclerosis Institute, talks about different types of fatigue in patients with multiple sclerosis (MS), as well as strategies to manage this significant symptom.

DocWire News: Today, we have Dr. Thrower here with us to talk about fatigue and multiple sclerosis (MS). Dr. Thrower, how common is fatigue in patients with MS?

Dr. Thrower: Fatigue is one of the most common symptoms we see in MS. For many people, it can actually be the presenting symptom of their MS, which makes it challenging because if you go to your primary care doctor with severe fatigue, there are so many things that could cause that. MS may not be the first thing that comes to mind.

DocWire News: What causes fatigue in patients with MS?

Dr. Thrower: That’s the million-dollar question. I would back up and say that there are two types of fatigue we see in MS. There’s something called lassitude, which is non-exertional, non-heat-related fatigue. And then there’s another type, called nerve fiber fatigue. Nerve fiber fatigue is weakness, or visual loss, or cognitive changes that are provoked by a sustained activity or by heat. That one [type of fatigue], we think we have a little better grip on. That probably is due to old areas of demyelination, areas where the insulation of the nerve fibers have been stripped away, either in the brain or spinal cord. The lassitude is a little more challenging, and there has been quite a bit of research on that. We think that there may be components from actual structural damage, so damage to deep gray structures, like the thalamus, have been associated with a higher risk of lassitude in MS. It may even be immunochemical. A lot of the inflammatory changes that we see with MS are mediated through inflammatory chemical messengers or cytokines. Those may play a role in fatigue in MS.

I would also say that when we talk about fatigue, we’ve got primary MS fatigue, which is those two things, the lassitude and the nerve fiber fatigue. And then we’ve got secondary MS fatigue. If you have disrupted sleep because your legs are spasming at night, or maybe because you have urinary frequency, that could lead to daytime fatigue. If you’re on medications—many of our antispasmodics, for instance, can be sedating—that could cause fatigue. If you have physical disabilities—maybe your walking has been impacted from your MS, and you’re doing things to compensate. For instance, if you have foot drop and you’re having to circumduct your leg or swing the leg out and around, you’re now using accessory muscles to walk that normally, you wouldn’t use. That can cause an increase in energy expenditure and lead to fatigue.

DocWire News: How does MS fatigue differ from regular fatigue?

Dr. Thrower: When we say fatigue, all of us get tired from time to time. By definition, MS fatigue should limit the person’s ability to function. It is a whole other level of fatigue. People with MS have described their lassitude as like having a lead blanket thrown over them. Cognitively, they know what they want to do. They want to go to the grocery store. They want to go to the movies. They want to do things, their normal daily activities, but they’re physically just unable to get out of the chair or get out of bed and do that. The other analogy that I really like, that I think is very descriptive, is people say it’s like trying to swim with a fur coat on. It was just an overwhelming heavy, sinking sensation that just you can’t physically overcome.

DocWire News: How does MS fatigue affect quality of life in these patients? Maybe things like social interactions, driving, working, etc.

Dr. Thrower: Fatigue impacts people with MS in so many different ways. There are vocational implications for fatigue. Studies vary, but if you look at why people change their vocation or maybe even leave work altogether, the two competing symptoms that we see in MS are either fatigue or cognitive dysfunction, so fatigue is either the first or the second most common cause for vocational disability in MS. You do see impacts on just activities of daily living, getting out of bed, being able to play with your kids, being able to go to the grocery store. Social activities are just all impacted by fatigue. And one of the cruel things about fatigue in MS is it is largely an invisible symptom.

If someone has walking issues, if you see someone using a cane, walker, or wheelchair, that symptom is obvious to everybody. Fatigue is not obvious, and it’s very frustrating for people with MS. Here is a symptom that drastically impacts their quality of life, but the average person can’t see it. It leads to issues within families. We see conflicts within spouses, where there are, sometimes, accusations that the person’s not trying hard enough or that they’re lazy. It’s such a ubiquitous and insidious symptom that affects so many people with MS.

DocWire News: Can caregivers or family members help patients manage with their fatigue?

Dr. Thrower: I think for caregivers, support partners, and family members, the first thing that helps is just being aware of the fatigue. Acknowledging that it exists and that it impacts the quality of life for a person with MS is half the battle. Becoming knowledgeable about what it is, what it’s like, having the caregiver read up on it. There are a lot of resources out there from the Multiple Sclerosis Foundation, the [Multiple Sclerosis Association of America], [and] National MS Society all have great resources for reading up and educating oneself on fatigue. Coming up with ways that you could recognize when a person’s having a good day or a bad day with energy levels and being able to jump in and help out with, whether it’s housework or activities. Maybe someone else takes the kids to soccer that day or otherwise, and coming up with some flexibility and planning—that would be a big help.

DocWire News: What treatments are currently available for MS fatigue?

Dr. Thrower: There is no FDA-approved treatment, interestingly, for fatigue. When we think about the average person with relapsing-remitting MS, we put all of our treatments into one of three boxes. We’re either managing relapses, we’re treating symptoms, or we’re changing the course of the disease overall. Generally, we think of fatigue as fitting into that second box. It’s symptom management. It’s a very important part of symptom management. So, not everything is medication-related. We do believe that regular exercise and a healthy diet will help in terms of managing fatigue. Good sleep, hygiene, managing other symptoms that might be impacting sleep. Minimizing medications that are sedating might help with fatigue.

Then we get into prescription medications. Like I said, there’s no FDA-approved treatment option, but that doesn’t mean we don’t try things. There’s an old medication called Amantadine, which is an old anti-influenza drug, that helps some people with their energy levels. We use Modafinil or the sister medicine, Armodafinil. These are drugs that were designed to treat narcolepsy, but in some people, they can help with fatigue in MS. And then, the true stimulant drugs, your Ritalin Adderall-type medications, can be used to help with fatigue.

That other type of fatigue, nerve fiber fatigue, which is the more exertional or heat-related fatigue. There are a class of drugs called Aminopyridines, so 4-Aminopyridine or 4-AP. There’s a prescription form called Dalfampridine. They’re both prescriptions. One’s FDA-approved and one’s not. Those can actually sometimes help with that nerve fiber fatigue. Those medications work on potassium channels on those naked nerve fibers, and may actually help people have better endurance and better heat tolerance.

DocWire News: What is your advice for patients with MS fatigue?

Dr. Thrower: Talk to your healthcare team about it. One of the things that I believe very strongly is that managing MS really requires a comprehensive and integrated team approach. At the center of that team is the person with MS and their family. If fatigue is a really serious symptom, the person needs to really let the healthcare team know about that. Then maybe we get the person into a reconditioning program through physical therapy and exercise physiologists, maybe have the nutritionist work with them on cleaning their diet up. Then try to think about whether medications are going to be appropriate. Right now, we think of that third box, the preventing disease progression, not so much as symptom management, so that’s still vitally important, but it’s important that we try to separate those two out as well, that we let people know that there are long-term medications to stabilize their disease that may not help with their symptoms like fatigue that they’re dealing with right now on a daily basis.

For more about MS fatigue, watch Dr. Zivadinov’s discussion on MS fatigue here.