Multiple Sclerosis Discovery -- Episode 50 with Dr. David Tabby

[intro music]   Host – Dan Keller Hello, and welcome to Episode Fifty of Multiple Sclerosis Discovery, the podcast of the MS Discovery Forum. I’m your host, Dan Keller.   This week’s podcast features Dr. David Tabby, who discusses the use of balance vests in people with MS. But first here are some new items in the MS Discovery Forum.   According to our curated list of the latest scientific articles related to MS, 65 such articles were published last week. We selected one of these articles as an Editor’s Pick. It’s a large case-control study in the European Journal of Clinical Investigation demonstrating that MS is associated with more than a six-fold increase in the risk of venous thromboembolism. To see this week’s articles, go to msdiscovery.org and click on Papers.   Our Drug-Development Pipeline includes continually updated information on 44 investigational agents for MS. During the month of July, we added 6 new trials, we updated information on 6 other trials, and we added 56 other pieces of information. The drugs with important additions and changes are alemtuzumab, dalfampridine, dimethyl fumarate, fingolimod, glatiramer acetate, GNbAC1, interferon beta-1a, interferon beta-1b, masitinib, natalizumab, rituximab, RPC1063, and teriflunomide. To find information on all 44 compounds, visit msdiscovery.org and click first on Research Resources and then on Drug-Development Pipeline.   [transition music]   And now to the interview. Dr. David Tabby is an adult general practice neurologist with a subspecialty in multiple sclerosis in Bala Cynwyd, Pennsylvania. He was formerly associated with Drexel University College of Medicine. We spoke about balance vests for people with conditions that impair their balance. He first describes what the vest is.   Interviewee – David Tabby       The balance vest looks like a bulletproof vest; it's a black nylon vest that's worn over the torso like a typical vest. And it was discovered by accident, I suppose, by a physical therapist from California called Cindy Horn who was treating people with Parkinson's disease, and she was troubled by the fact that these people tended to be forward-flexed at the hip and walk like they're looking at the floor. So she wondered if she put some weights on their back, if she could tip them more upright. And she did that and it worked, but she also discovered that people had better balance. Falls is a major cause of morbidity and even mortality in Parkinson's disease, so this was big.   So the next step was that she developed a system to figure out how to maximize the weighting of the torso, consisting of perturbations – pushes really – of the shoulders forward or back or side to side, twisting the pelvis and seeing the rebound to that, and figuring out by trial and error a way of using weights to dampen those oscillations really. She worked on it for years; this process started about 15 years ago, I think, maybe more than that now. And then she realized that there were other people besides Parkinson's patients who could benefit from it. Multiple sclerosis patients turned out to be a big one, but other types of people with cerebellar disorders, and ataxias, and even peripheral neuropathy; if the problem was balance, it seemed like the balance vest could make a difference.   Interviewer – Dan Keller           What about for vestibular dysfunction, maybe those 20% of people who shaking their head doesn't fix the problem?   Dr. Tabby I don't think we have a lot of data on vestibular patients, but that's important. It's not exactly the topic of this talk, but we've had some really great results in post-concussive injury. My theory on this is that kind of everything doesn't work right after concussion, you have to think consciously about all these things that used to be automatic, including walking. And if you imagine that you only have a finite supply of mental energy to expend on different tasks, if you're expending a lot of that on balancing, there's not as much left for thinking and talking and other normal cognitive tasks. So we've seen unexpectedly some significant improvements in cognitive function from people who had concurrent balance disorders freeing up, if you will, their cognitive reserve to do what it's supposed to do instead of worry about why you're not falling over.   MSDF Is there a proposed mechanism here; is it only dampening oscillations or is there some sort of perceptual thing that it's enhancing, or how's it working?   Dr. Tabby This is not known, there are only theories at this point. I had started on a study while I was still at Drexel with the Department of Physical Therapy who had built a device for measuring sitting balance; you know, taking the entire lower extremity out of the equation. It's basically like a chair without legs on a half dome. So if you don't have a disorder, in fairly short order you can teach yourself how to sit on the chair and not fall over. It sits on a very sensitive pressure plate, and then you can measure how much deviation there is from the exact center point. Your feet are strapped so you can't move them around, and you're supposed to hold your arms over your chest, so you have your torso and head to move around. Then you try to do certain exercise. You're looking at a screen that has a big circle on it and you're supposed to roll your center of gravity forward maybe to 3 o'clock on a clock face, and 6 o'clock, and 9 o'clock, and go back to the center, and you can see how much progress you're making.   And we had started on an experiment to put the balance vest on people and see if they did better with the balance vest with the lower extremity, you know, taken out of the equation. We didn't collect enough data to make a conclusion about that. I think it's really fascinating, though, because if you carry your cell phone in your shirt pocket, doesn't that change the vector forces about your torso, but somehow we don't seem to fall over over that. Maybe it does change things but it's not big enough to notice. We need a lot of research into determining what the exact mechanism of action is for the vest, because there's a lot of question marks about it right now.   MSDF So how do they fit this vest, adjust it? How long does it take?   Dr. Tabby An experienced physical therapist can do a good fitting probably in 30 to 45 minutes, sometimes a little longer than that depending on how severe the problem is. We generally video the patient before, during, and after of some more objective confirmation of the changes. There are tests both in standing still and also walking. We would like to bring some more quantification into that process about ways to get data about walking, like a pressure plate that you walk over and times the interval between heel strikes and variability from the center line, but that's all in the future. It's been very just pragmatic right now. Patients almost always leave from their fitting session knowing that they could balance and walk much better than when they came in, and they're all anxious to get their permanent vest soon. It's accomplished with quarter pound and half pound weights, and to be honest, I don't know how to do it; I didn't get trained, so I don't know exactly all the principles involved, you know, where you put the weight, how far from the midline you put the weight. Do you put it up high on the torso, do you put it low on the torso?   MSDF So counting the weights and the vest, how much extra weight is a patient carrying around, and does that become a burden?   Dr. Tabby We don't use more than 2 lbs of weight, and then the vest itself is about 2 lbs. Now we're also working on a t-shirt or an undershirt, a close-fitting athletic-type shirt that we can incorporate the weights right into that. That's really nice because it can be worn under any clothing at all, and the complaint about it being hot won't be as relevant. It does not include a lumbar brace, as this standard brace does. A lot of patients like the brace, though, they think that that contributes somewhat to the sense of balance that they get.   MSDF For an MS patient – and I realize they vary a lot in their disability – is it fairly easy to put this on once they have it?   Dr. Tabby Some might require help. It zippers and tightens up with Velcro straps, so it takes some coordination to get it on.   MSDF Is there any residual effect? I mean, you said they have an immediate effect, but once they take it off is there any benefit or do they always have to wear it?   Dr. Tabby I'm so glad you asked that, because a lot of patients find that they can wear it intensively for two or three days and then not wear it for a day or two and still have carryover benefit. Exactly how that works, I'm not sure either, but that's what they say.   MSDF You've used this with patients. How many in your practice have been trying it?   Dr. Tabby We have over a hundred in the last five or six years.   MSDF Is there any downside?   Dr. Tabby You have to change your wardrobe. I'm kidding a little bit, but I do have a patient… You know, the vest comes in every shade of black that you want, so she changed her wardrobe to only include black so the vest doesn't look strange. You know, if you wear big, loose clothing, you could probably have it under something and it might not be obvious. You know, the fashion sense is an issue, the weight by the end of the day and the temperature.   MSDF Sounds like those are all things that can be worked out sort of cosmetically; color and different fabric eventually or something.   Dr. Tabby Yes.   MSDF Have you done any of the research on this, or you've just been using it? I see there's actually a fair bit published about it.   Dr. Tabby We have a trial that we're working out the kinks of now. We wanted to do a trial with other medications that might help with walking; I'm not sure it's going to be feasible to do that, but just accumulating other types of data that doesn't exist right now, like great systems for measuring body position and movement with small wearable sensors on the body, as well as pressure plates on the floor that you can walk along a pathway. We'd like to do more specific research in specific conditions. Of course, my interest is mainly in MS, but I know I've been able to help other patients with it. You know, it's important if this therapy is going to help more people, that there be as much published as possible that shows that this is a real phenomenon; it's worthy of patients' and physicians' attention.   [transition music]   Thank you for listening to Episode Fifty of Multiple Sclerosis Discovery. This podcast was produced by the MS Discovery Forum, MSDF, the premier source of independent news and information on MS research. MSDF’s executive editor is Robert Finn. Msdiscovery.org is part of the non-profit Accelerated Cure Project for Multiple Sclerosis. Robert McBurney is our President and CEO, and Hollie Schmidt is vice president of scientific operations.   Msdiscovery.org aims to focus attention on what is known and not yet known about the causes of MS and related conditions, their pathological mechanisms, and potential ways to intervene. By communicating this information in a way that builds bridges among different disciplines, we hope to open new routes toward significant clinical advances.   We’re interested in your opinions. Please join the discussion on one of our online forums or send comments, criticisms, and suggestions to [email protected].    [outro music]