Huntington’s disease (HD) is a rare genetic disorder that causes the breakdown of nerve cells in the brain. The onset and progression of the disease varies from one person to another. The most common form of the disease occurs in middle age and progresses slowly over the course of 15-20 years with a gradual loss of mental abilities and control of body movements. People with HD become increasingly impaired, and experience uncontrolled movements, loss of intellectual ability, and behavior changes. In the later stages of the disease, people with HD lose the ability to walk or speak. They usually become completely dependent on others for activities of daily living. Ultimately, the most common causes of death associated with HD include pneumonia due to aspiration of food or impaired swallowing, and heart disease or infections.
Motor Symptoms—The Dancing Disease
George Huntington, the young American doctor who first described HD in the medical literature in 1872, originally named the condition Chorea (Greek for dance) due to its hallmark sign. In fact, the way the trunk, arms and legs of someone who has HD move and twist involuntarily does somewhat resemble dance-like movements. Later it was named Huntington’s chorea and then Huntington’s disease. The motor skill impairment ultimately progresses to become severely disabling. In later stages patients may also experience slow, repetitive and/or prolonged, stiff positions of the neck, arm, and trunk (dystonia), move very slowly, have severely impaired gait and difficulty with eye movements, and eventually lose all fine motor skills.
Cognitive Functions and Behavior
HD is a complex neuropsychiatric disease that also affects the ability to think and communicate (cognitive functions). Often these problems appear before the first signs of motor impairment emerge. These can include difficulty paying attention, problems with mental planning and flexibility, inability to successfully perform mental tasks (e.g., balancing a checkbook), and memory loss.
Additionally, there can be worrisome behavioral changes. These can include anxiety, depression, lack of motivation, impulsivity and mood swings. In fact, in the first year after diagnosis, there is a higher incidence of depression and suicidal thoughts. As many as 40% of people with HD may experience depressive symptoms. Speaking with a doctor is important if you or your loved one has HD, and keeping an eye out for depression is a smart idea.
An Inherited Disorder
The disease is passed down from a parent to a child in what is called an “autosomal dominant” pattern. This means that each child with an affected parent has a 50% chance of inheriting the disease. It can affect both males and females, and occurs in all ethnic groups.
HD may be considered a family disease because it has an enormous impact on the parent with the disease, and on the children, who may or may not want to know if they carry the gene passed on from their parent. People with late stage HD will become completely disabled and therefore, dependent on family members for care, which may be associated with significant psychological and social repercussions for the family. Unfortunately, there is currently no cure for HD.
Genetic Testing—A Tough Decision
There are genetic tests that can determine whether a child carries the HD gene like their affected parent. For those with a parent who has HD, the decision to test for the gene is a personal one. At-risk individuals should consider the many implications that genetic testing may have when making the choice about whether to get tested or not. It can be helpful to seek the help of a genetic counselor. Here are just a few questions to think about before making that decision:
- Will the anxiety of not knowing be worse than the certainty of knowing that you will develop HD?
- How will your decision affect your family, spouse, and children?
- Will knowing whether you carry the HD gene help you prepare yourself and your family for the future? Or will it cause more worry and anxiety?
- Does your health insurance pay for the test? Will it affect future health insurance coverage?
- How will knowing affect you in your life and work?
It is particularly important to know how you might feel knowing that there is currently no cure if you test positive for the gene. The best thing you can do is find adequate support and become as informed as possible about how to make the best decision for you, your family, and your life.
Staying Positive & Active
Offering guidance to someone with HD can be difficult because of its progressive nature and the emotional issues surrounding the disease. But it’s worth reminding people that this is a slow moving disease, and there is often time to focus on quality of life. People with HD may need to seek support in coping with the stress of knowing about the fatal course of the disease. They may need encouragement for enjoying the time they have before the disease becomes disabling. There are important things to do, including:
- Becoming as knowledgeable about the disease as you can
- Staying active and healthy for as long as possible, as much as your condition and the course of the disease allows. A daily regimen of exercise can help you feel better physically and mentally
- Managing your diet for optimal health. You may want to work closely with a nutritionist since the condition often affects metabolism and can cause people to lose weight unintentionally
- Speaking with your doctor about the best overall health plan for you
- Working with your healthcare team to manage symptoms via speech therapy and physical therapy
- Seeking treatment for depression and anxiety when appropriate
- Developing a support network of family and friends
- Connecting with the HD community via online resources and in person when possible
Focus on Research and Cure
This is a very exciting time for emerging research in the Huntington’s community. With increased interest and funding, new treatments for managing the disease are under investigation. Physicians and scientists are dedicated to advancing research with the hope of finding a cure. Research into HD therapies can be put into two categories:
- Treatments to improve symptoms: These do not stop the disease, but may help people live better
- Treatments to modify disease: These work to slow down the course of the disease, so that people may live longer
The enthusiasm from patients and investigators alike has created a hopeful and exciting environment. If you are interested in learning more about clinical research in Huntington’s Disease, or finding a trial for yourself or a loved one go to clinical trials.gov and Pfizer: Find A Trial.
Dr. Ottavio Vitolo, MD, is a neuropsychiatrist, an instructor of psychiatry at Harvard Medical School, and a Medical Director and Clinical Lead at Pfizer.