Have you had a referral for a patient with Amyotrophic Lateral Sclerosis – ALS? What did you think when you received that consult? How did you proceed with therapy? Were you uncertain what to do?
Amyotrophic Lateral Sclerosis – ALS or Lou Gehrig’s disease – is a progressive neurological disease that involves degeneration of both upper motor neurons (UMN) and lower motor neurons (LMN) that control voluntary movement. The result is progressive muscle atrophy, weakness, spasticity, dysarthria, dysphagia and respiratory failure. Patients are described as having either limb or bulbar (speech & swallowing) onset ALS depending on what area is more prominently involved when they are first diagnosed. About 25% of ALS patients have bulbar symptoms as the initial complaint. No matter what type of onset the patient has, symptoms of ALS will eventually spread to other parts of the body.
I have been fortunate to be the speech pathologist at the Muscular Dystrophy Association (MDA) ALS Center at Houston Methodist Neurological Institute lead by one of the frontrunners in the field of neurodegenerative diseases, Dr. Stanley Appel. It was the first multidisciplinary ALS Clinic created in the country. Eleven specialty areas are represented in the clinic including PT, OT, SLP, social work, nutrition, respiratory therapy, sleep medicine, pulmonary medicine and neurology. We call ourselves “Team Hope” and our goal is to “knock out ALS”. We see approximately 300 ALS patients a year.
I recognize this is an “Ivory Tower” set up. But like many of you reading this, prior to coming to Houston Methodist Hospital 15 years ago, I had seen only two or three ALS patients hospitalized at the end stage of their disease. Now remember, this was before I had access to the “knowledge base” of professional email lists and the web. I recall thinking, “What am I supposed to do?” I knew from graduate school that ALS was a progressive disease and the patients’ lost their lives. I am embarrassed to say I don’t believe I did much of anything, because I did not understand the disease. That has certainly changed!!
Conventionally, the mainstay of “therapy” for ALS patients has been symptom management and NOT active therapy such as oral motor exercises or the Masako maneuver that can be fatiguing. There is no treatment that has been shown to improve swallowing in ALS to date. Even with the progressive dysphagia, strategies can be useful to allow the ALS patient to continue to eat/drink for as long as possible. The goal is to maintain weight, maintain efficiency of intake, and minimize the risk of aspiration. Consistency modification may increase efficiency when there is difficulty chewing. A chin flex position can assist in airway closure. Strategies/compensations should be based on patient presentation. Monitoring the patient’s weight and asking how long mealtimes take can provide an idea of how efficient intake is. A high protein and high fat diet is recommended for ALS patients to help them maintain weight and possibly muscle. The theory being that the high protein feeds the muscles and lipids in the fat have demonstrated to provide nerve protection. Research suggests that at some stages of the disease process, people with ALS can become “hypermetabolic,” burning calories at a faster rate than normal. If not carefully managed, the patient begins to lose weight and important muscle stores.
Most SLPs I know entered the field because they want to “do something to help others” and this paradigm shift in treatment delivery can be difficult. We are used to active treatments. The role of active exercise is controversial in the ALS community. Findings have been inconclusive. Primarily this is because exercise trials on ALS patients are impossible to control. There are far too many variables, no way for every patient to be on the same program and exercise at the same intensity for the same period of time and no one does long term follow up that can be compared with an age/gender matched control group that has NOT exercised under very controlled circumstances. We are beginning to look at exercise differently. Basic science data on mouse models of ALS suggest that moderate intensity aerobic exercise delays disease onset and slows progression. Most clinicians agree that mild to moderate amounts of activity levels tailored to the individual patient’s level of function are generally beneficial early in the disease. Literature is trending to indicate that taxing power muscles is damaging and high intensity exercise is never good in these patients. Training accessory muscles may be a better approach.
That being said, it is important to recognize that this is limb or basic science literature and we cannot generalize it to the bulbar musculature. Our speech and swallowing muscles are at work 24/7 managing saliva, eating and speaking. Our other muscles are NOT working the same way – we are “at rest” most of the time even with daily activities. We need a better understanding of the effects of exercise on swallowing in ALS before we jump into it. The good news is we’re working on it! Dr. Emily Plowman at the University of South Florida presented some exciting preliminary/pilot data to show that moderate intensity expiratory muscle strength training (EMST) was effective for improving max expiratory pressures and voluntary cough function in ALS at the Dysphagia Research Society last year. This research certainly has the potential for impacting swallow function/safety.
Working with ALS patients is challenging and rewarding. It is difficult to watch the progressive deterioration in these patients. Before initiating a therapeutic regime with a patient who has a progressive neuromuscular disease it is important to understand the disease process. The bottom line is that we really don’t know about exercise and ALS but are in the early stages of figuring things out. More research is needed but it seems from the basic science models and preliminary data emerging that there might be a place for intervention. For now, until we understand exercise and bulbar function better, the primary treatment for ALS patients continues to be symptom management especially beyond the early stages of the disease.
Links of Interest
- For more information on Houston Methodist Hospital visit the website www.houstonmethodist.org
- For more information on ALS visit http://mda.org/disease/amyotrophic-lateral-sclerosis
- Alexianu, M.E., & Appel, S.H. (2005). Amyotrophic lateral sclerosis. In Motor disorders.2nd Edition. David S. Younger, MD. Editor. Philadelphia, PA: Lippincott Williams & Wilkins.
- Chen, A., Montes, J. & Mitsumoto, H. (2008). The role of exercise in amyotrophic lateral sclerosis. Physical Medicine and Rehabilitation Clinics of North America, 19, pp. 545-557.
- Katzburg, H.D., & Benetar, M. (2011) Enteral tube feeding for amyotrophic lateral sclerosis/motor neuron disease. Cochrane Database of Systematic Reviews, 1. Doi: 10.1002/14651858.CD004030.pub3
- Lewis, M., & Rushanan, S. (2007). The role of physical therapy and occupational therapy in the treatment of amyotrophic lateral sclerosis. NeuroRehabilitation. 22, pp.451-461.
- Lopes de Almeida, J.P., Silvestre, R., Pinto, A.C., & de Carvalho M. (2012). Exercise and amyotrophic lateral sclerosis. Neurological Sciences. 33, pp.9-15.
- Miller, R. M., & Britton, D. (2011). Motor neuron disease. In Dysphagia in neuromuscular diseases (pp.144-153). San Diego, CA: Plural
- Plowman, E.K, Domer, A, Watts, S, Gaziano, J, Tabor, L.S, D, Richter, J, Gooch, C, Vu, T. The Impact of Exercise on Bulbar Function in Individuals with Amyotrophic Lateral Sclerosis. 21th Annual Dysphagia Research Society Meeting, March 14, 2013, Seattle, WA