Tuesday, September 2, 2014
Constant Movement and Progression of Huntington's Disease
I am doing a research paper on Huntington's Disease and I know a woman with the disease. Her arms and legs and head are always moving and I was wondering why that happens? Does it worsen as the disease progresses? Is there anything that people can do, when diagnosed witht he disease, to make it so the side affects aren`t as severe?
The movements you describe are called Chorea. Huntington's disease was initially called Huntington's chorea. We now refer to it as Huntington's disease because chorea is only one feature of the disease and is present in varying degrees in different individuals. Some individuals with the disease have little, if any, chorea. The chorea sometimes gets better as the disease progresses and sometimes it gets worse. Other features of HD include progressive cognitive impairment, behavioral problems, trouble swallowing and trouble walking.
The movements are caused primarily by an imbalance in control of neuronal activity in an area of the brain called the basal ganglia. The basal ganglia include several groups of neuron clusters, including the caudate nucleus and the putamen, that are involved in controlling movements. Different diseases affect these parts of the brain differently. HD leads to increased movements. Parkinson's disease (PD) often leads to decreased or slowed movements. However, some of the medications used to treat the slowness of movements of PD overshoot their goals and cause increased movements called dyskinesia, which are very similar to the movements seen in HD, chorea.
There are no drugs that have been specifically proven and approved for treating chorea. There are some medications that we use that help some patients. The movements tend to get worse when the individual is anxious. Therefore, some of the anti-anxiety medications, benzodiazepines, like Klonopin, Valium or Ativan can help. However, these medications can make a person sleepy or more likely to fall.
There is a medication called Amantadine, that was originally prescribed to treat the flu. It sometimes helps both the dyskinesia of PD and the chorea of HD. This medication seems to work to some degree in about half the individuals that we try it on.
Some people find some of the medications that were first designed to control seizures helpful for controlling chorea. These medications include Depakote and Keppra.
There is a medication called Tetrabenazine that is used in Europe and Canada that is currently being considered by the FDA for approval in the United States, but is not yet commercially available here. I have had some patients who have responded well to this medication but not everyone tolerates it.
Finally, some patients respond best to a class of medications called neuroleptics. These would include medications like Haldol or Risperidal.
For additional information about HD, you may want to check out some of the following websites:
The Huntington's Disease Society of America. This group focuses on helping families with HD, funding clinics treating HD and funding research in HD. http://www.hdsa.org/
The Huntington's Study Group. This group focuses on current clinical research trials. http://www.huntington-study-group.org/
We Move. This site has information about many different movement disorders including HD and PD. http://www.wemove.org/
Sandra K Kostyk, MD, PhD
Assistant Professor of Neuroscience
Clinical Assistant Professor of Neurology
College of Medicine
The Ohio State University