Dr. Emily Plowman, one of our Clinical Management Grant awardees, recently published a promising case report on a person with early-stage ALS who has been participating in a mild-intensity respiratory strength training program. The individual has been doing the strength training program with Dr. Plowman and her team at the University of Florida in Gainesville, Florida, over the past 24 months.
Dr. Plowman, associate professor in University of Florida’s Department of Speech, Language and Hearing Sciences and Neurology, and her colleague, Dr. James Wymer, set out to explore, for the first time, how both expiratory muscle strength training (EMST) and inspiratory muscle training (IMST) impact a person with ALS. They found that the mild-intensity program was safe and improved function in a person with ALS who was early in disease progression.
ALS is a devastating disease that eventually attacks a person’s bulbar muscles of the head and neck, impacting speech, coughing, and the life sustaining functions of swallowing and breathing. Impairments in breathing and swallowing contribute to fatal aspiration, malnutrition, and respiratory issues that account for 92 percent of ALS mortality.
The mild-intensity training program involves daily exercises for both the inspiratory and expiratory muscles. These muscles are responsible for the vital functions of breathing and ventilation (inspiratory muscles), as well as airway clearance/protection and cough function (expiratory muscles) using a handheld trainer.
In an earlier study, Dr. Plowman found that EMST was well-tolerated in people with ALS and led to improvements in maximum expiratory pressures, airway clearance, and swallowing measures.
We asked Dr. Plowman to share her thoughts on respiratory training and her newly published case study.
Thank you for joining us today and congratulations on the success of your study! Can you start by describing your approach for this study?
The guiding premise of this case report and our previous group studies (see Plowman 2018; Plowman 2015; Tabor, 2017) is to enable individuals with ALS to engage in a proactive and patient-centered approach. This approach affords the patient the opportunity to make decisions regarding their treatment course compared to more historical approaches, whereby the disease has typically dictated the timing and implementation of interventions in a more reactive manner (i.e. once dysfunction is clinically identified).
We feel the traditional reactive management approach, such as the implementation of non-invasive ventilation once forced vital capacity drops below 50 percent predicted, doesn’t take advantage of the early potential people with ALS may have to maintain or even improve strength and physiologic reserve for the vital functions of eating, drinking, and breathing.
Further, historical approaches have been palliative in nature, with the overall goal to reduce pain and increase comfort and quality of life using devices, compensations, and environmental modifications. Although these factors are important, this approach doesn’t target improving or maintaining physiologic function. Our approach is to actively target underlying physiologic function early, before the development of dysfunction.
What are the goals of your approach?
The goal of this approach is to increase a patient’s physiologic capacity, reserve, or ‘savings account’ for breathing, coughing, and swallowing through the use of mild- to moderate-intensity exercises on muscles related to these vital functions. Given the high likelihood that breathing and swallowing will be negatively impacted during ALS disease progression, waiting to apply management strategies in a reactive manner following impairment manifestation allows the disease to dictate or define management decisions.
We prefer to hand over decision-making to the patient, who we find feels empowered to at least have some control over certain aspects of their treatment plan in a more active, and importantly, proactive manner before the appearance of such symptoms.
How has funding from The ALS Association impacted your research studies?
The ALS Association made it possible for our group to continue our efforts to study and learn about the potential role of exercise in people with ALS.
The findings from this report were clinically and functionally significant for the individual. At the commencement of the study, his intervention peak cough flow (which represents a person’s physiologic capacity or ability to defend the airway) was below expected levels and at a level of concern for being able to expel tracheal aspirate.
Throughout the treatment program, as the individual improved his inspiratory and expiratory strength, so too did the physiologic capacity for him to defend his airway.
We’ve noted such improvements in other studies and recently completed a large randomized sham control trial in 46 individuals using this method that was also funded by The ALS Association. We’re currently analyzing these data and will present results in December at the International Symposium on MND/ALS in Glasgow, Scotland.
Are there any important caveats to your study that you would like people with ALS to be aware of?
First, this work and the studies we’ve published in the past two years have been in early affected people with ALS, whose forced vital capacity has been greater than 70 percent predicated. Second, the intensity of the exercise training on the breathing muscles is mild to moderate and completed in the home.
Therefore, timing of intervention (preferably at or around time of diagnosis), dose, and intensity (low to moderate but not high) are critical factors. It’s likely that these findings don’t translate to people with ALS with more advanced progression, or engagement in high-intensity exercise – both of which we don’t recommend.
Although we possess great excitement regarding the potential for a proactive and active exercise program to prolong the vital function of breathing, eating, and airway clearance; more research is clearly needed to validate the findings in this case report.
Case Study Summary
A 58-year-old male joined the study two months post-diagnosis and had experienced slurred speech one-and-a-half years pre-diagnosis. He was confirmed to carry the C9orf72 mutation, the most common inherited cause of ALS.
The program consisted of an at-home inspiratory and expiratory muscle strength program that was measured by using calibrated hand-held resistance trainers. Over a 24-month period, the individual completed 50 repetitions per day, five days a week. He self-reported completing 100 percent of the trainings without any fatigue, discomfort, or adverse effects.
Following the 24-month training period, the individual demonstrated an increase of:
- 89 percent in maximum inspiratory pressure (MIP)
- 82 percent in maximum expiratory pressure (MEP)
- 98 percent in peak cough flow
There was no change in pulmonary function, as measured by forced vital capacity (FVC). The total ALS Functional Rating Scale-Revised (ALSFRS-R) score decreased two points from 46 to 44. It is unclear whether the individual’s disease maintenance is related to the training program or if his disease simply has a slow progression.
The case study reveals that the combined inspiratory/expiratory training approach is safe and feasible and can demonstrate improved bulbar function in a person with ALS.
NOTE: Dr. Plowman and her colleagues are currently enrolling in a randomized clinical trial to test a similar respiratory training approach that is funded by The ALS Association. For more information about the trial, click here https://clinicaltrials.gov/ct2/show/NCT03202017?term=plowman&cond=ALS&rank=6. The ALS Association will update the community with its results.
Combined respiratory training in an individual with C9orf72 amyotrophic lateral sclerosis.
Raele Robinson, Lauren C. Tabor-Gray, James Wymer, Emily K. Plowman.
Annals of Clinical and Translational Neurology. First published: August 21, 2018.
Read the open access paper here.