Read Full Text: The effect of multidisciplinary rehabilitation on brain structure and cognition in Huntington’s disease: An exploratory study (Free to access)
Journal: Brain and Behavior (Impact Factor: 2.072)
Year Published: 2015
Ranked 50th on our 2014-2019 list of the 50 most influential articles
Huntington’s Disease is a genetic disorder that causes a progressive breakdown of nerve cells in the brain. Symptoms often appear in patients’ 30s or 40s.
The time from the emergence of symptoms to the patient’s death is typically between 10-30 years.
There is currently no cure for Huntington’s Disease and medications, at best, help manage symptoms, as opposed to actually altering the course of the disease.
While we never want to give our patients false hope, and we can’t predict the future, and there are new potential treatments on the horizon for Huntington’s Disease.
The neuroplasticity of the brain continues to surprise researchers, even in cases where we once thought the degeneration of the brain was fixed. In this very early, very exploratory research, participants in multidisciplinary rehabilitation demonstrated increased gray matter volume in specific areas of the brain. They also demonstrated significant improvement in verbal learning and memory.
Let’s dive into what this means for our patients and the therapy we provide.
Important reminder about the symptoms of Huntington’s Disease
Like other neurodegenerative diseases, such as Parkinson’s Disease and Alzheimer’s Disease, Huntington’s disease affects a person’s functional abilities over time. Both physical and mental abilities are affected.
The presentation of symptoms varies from patient to patient, and I encourage you to look at the full range of symptoms laid out by the Mayo Clinic.
Most relevant to this study are the cognitive deficits, which have been shown to correlate to loss of gray matter in the brain.
What multidisciplinary therapy was provided in this study?
15 patients undertook multidisciplinary therapy for 9 months. The therapy consisted of:
- 1x/week supervised clinical exercise
- 3x/week self-directed home-based exercise
- Occupational therapy every 2 weeks
The team that designed the program consisted of:
- Physical therapists
- Exercise physiologists
- Occupational therapists
- Strength and conditioning specialists
What details were given about the OT that was provided?
Hidden in the article is a Word document with the details of all of the therapy provided! I’m attaching it here for ease of access:
Supplementary Appendix attachment (22.6 KB)
The short version is that OT consisted of the following exercises, designed to enhance cognition and executive function:
- Verbal planning
- Memory
- Problem solving
What assessments were used?
MRI images of the brain were an important outcome measure used in this study.
Cognitive and executive function measures (that OTs can administer) included:
What were the results—and why do the researchers believe that the therapy appeared to have some positive benefits?
The imaging showed that, as expected, there was gray matter loss in many areas of the patients’ brains. However, contrary to expectations, two specific regions actually showed brain matter increases. These regions were the right caudate and dorsolateral prefrontal cortex (bilaterally in this region).
Also, on the cognitive assessments, the researchers saw a steady decline on the majority of the tests—except there was a significant improvement in verbal learning and memory on the HVLT-R!
The researchers believe the improvements in gray matter and learning in those particular areas were correlated, as the dorsolateral prefrontal cortex has been shown to be a primary driver of memory retrieval and recognition.
This is exciting because it suggests that neuroplasticity may still be present in patients with HD—and that the plasticity seems amenable to therapeutic interventions!
This complements previous research, like we have seen in Parkinson’s Disease, which suggests that exercise can increase neuroplasticity. This also suggests that patients with Huntington’s Disease might find that lifestyle factors can play a role in the clinical presentation of the disease.
Takeaways for OT practitioners
(These are my personal takeaways, and were not mentioned in the article.)
1. These patients should be on our caseload.
Since Huntington’s Disease is rare, it might be intimidating when a new patient with the disease is scheduled to your caseload. But, on our caseloads is exactly where these patients need to be.
Even though we still have much to learn about this disease, we need to remember that there simply aren’t many answers for these patients out there–and, at this point, the most helpful thing we can do is to listen carefully to the individual in front of us. After all, we can be valuable partners and guides as they work to maintain their quality of life in the areas that matter most to them.
2. Just like in Parkinson’s Disease, exercise seems to hold promise in activating neuroplasticity. And, at the very least, exercise helps maintain physical health for as long as possible.
We’ve discussed in the Club how exercise can induce neuroplasticity in Parkinson’s Disease—and how that, in part, helps the brain combat the degenerative effects of the disease.
This current article suggests that the same may be true in Huntington’s Disease. But, overall, the evidence does not seem as robust in HD as in PD. The most recent article I could find specifically on the effects of exercise in HD found that the effects of exercise on cognition were “incongruent.”
So, even though this current article appears to hold promise, it’s our responsibility to keep tabs on the research for the latest developments. And, in the meantime, if I had a family member with Huntington’s Disease, I would certainly continue to recommend regular exercise. Not only would I optimistically hope that exercise might combat the effects of the disease—if nothing else, exercise can have a dramatic positive impact on mood, physical health, and overall quality of life.
(Possibly) Earn CEUs/PDUs for reading this article
Many of you can receive continuing education credits for reading this article. Here’s a form to help you do it, along with information to help you understand who qualifies.
And, here’s the full APA citation you might need:
Cruickshank, T. M., Thompson, J. A., D, J. F. D., Reyes, A. P., Bynevelt, M., Georgiou-Karistianis, N., … Ziman, M. R. (2015). The effect of multidisciplinary rehabilitation on brain structure and cognition in Huntingtons disease: an exploratory study. Brain and Behavior , 5 (2). doi: 10.1002/brb3.312