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Huntington's disease
By Mayo Clinic staffMayo Clinic Health Manager
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Definition
Huntington's disease is a progressive, degenerative disease that causes certain nerve cells in your brain to waste away. As a result, you may experience uncontrolled movements, emotional disturbances and mental deterioration.
Huntington's disease is an inherited disease. Signs and symptoms usually develop in middle age. Younger people with Huntington's disease often have a more severe case, and their symptoms may progress more quickly. Rarely, children may develop Huntington's disease.
Medications are available to help manage the signs and symptoms of Huntington's disease, but treatments can't prevent the physical and mental decline associated with the condition.
Symptoms
The signs and symptoms of Huntington's disease can vary significantly from person to person. Huntington's disease usually develops slowly, and the severity of signs and symptoms is related to the degree of nerve cell loss. Death occurs about 10 to 30 years after signs and symptoms first appear. The disease progression may occur faster in younger people.
Early signs and symptoms of Huntington's disease often include:
- Personality changes, such as irritability, anger, depression or a loss of interest
- Decreased cognitive abilities, such as difficulty making decisions, learning new information, answering questions and remembering important information
- Mild balance problems
- Clumsiness
- Involuntary facial movements, such as grimacing
Your family and friends may notice these changes before you become aware of them.
Later signs and symptoms of Huntington's disease can include:
- Sudden jerky, involuntary movements (chorea) throughout your body
- Severe problems with balance and coordination
- Jerky, rapid eye movements
- Hesitant, halting or slurred speech
- Swallowing problems
- Dementia
Young people who develop Huntington's disease may have signs and symptoms that mimic Parkinson's disease:
- Muscle rigidity
- Tremors
- Slow movements
Seizures may also occur in those with early-onset Huntington's disease.
When to see a doctor
See your doctor if you notice changes in your movements, emotional control or mental ability. These signs and symptoms can be the result of many conditions, so they don't necessarily mean you have Huntington's disease.
If you have a family history of Huntington's disease, you may want to talk with your doctor about genetic testing that can tell you whether or not you carry the defective gene. Deciding whether to be tested for the gene is a personal decision. For some people, the uncertainty of whether they carry the faulty gene is stressful and distracting. For others, the knowledge that they will develop the condition is burdensome. If you're uncertain whether testing is right for you, consider contacting a genetic counselor who can help you understand the implications of a positive or negative test result, walk you through the testing process, and help you weigh the pros and cons. Ask your doctor for help locating a genetic counselor.
Causes
Huntington's disease is an inherited condition caused by a single abnormal gene. Doctors refer to the illness as an autosomal dominant disorder because only one copy of the defective gene, inherited from either parent, is necessary to produce the disease. If one parent has the single faulty gene, the chance that an offspring will have the defect is 50 percent. Because signs and symptoms typically first appear in middle age, some parents may not know they carry the gene until they've already had children and possibly passed on the trait.
If your child doesn't inherit the faulty gene, he or she won't develop Huntington's disease and can't pass it on to the next generation. Everyone who has the gene eventually develops Huntington's disease, if he or she lives long enough.
In 2006, researchers discovered that the protein expressed by the Huntington's gene interacts with another protein to disturb the way that cholesterol accumulates in the brain. Cholesterol is essential for healthy brain cells and the network among those brain cells — but the cholesterol needs to be in proper levels and in the proper locations. When the network of brain cells is disrupted, motor skills, cognitive skills and speech can be affected. If scientists can figure out a way to disrupt this interaction between the proteins, they may eventually be able to develop a targeted drug therapy.
Risk factors
If one of your parents has Huntington's disease, you have a 50 percent chance of developing the disease. In rare cases, you may develop Huntington's disease without having a family history of the condition. Such an occurrence may be the result of a genetic mutation that happened during your father's sperm development.
Complications
After onset of the disease, signs and symptoms continue until death. Though the signs and symptoms vary from person to person, vital functions, such as swallowing, eating, speaking and walking, usually degenerate over time. Depression is common in Huntington's disease, and some people are at risk of suicide. However, death generally occurs as a result of complications of the disease, such as a fall or an infection like pneumonia.
Preparing for your appointment
Your first appointment may occur because you or a loved one has noticed that you have some signs and symptoms of Huntington's disease, or it may be because you know one of your parents had the disease. You can see your primary care physician initially, but if you're diagnosed with Huntington's disease you'll likely be referred to a neurologist — a doctor who specializes in treating nervous system disorders — for your care.
Because appointments can be brief, and there's often a lot of ground to cover, it's a good idea to be well prepared for your appointment. Here's some information to help you get ready for your appointment, and what to expect from your doctor.
What you can do
- Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
- Write down key personal information, including any major stresses or recent life changes.
- Make a list of all medications, as well as any vitamins or supplements, that you're taking.
- Ask a family member or friend to join you. Sometimes it can be hard to remember all the information provided to you during an appointment. Someone who accompanies you may remember something that you missed or forgot.
- Write down questions to ask your doctor.
Your time with your doctor is limited, so preparing a list of questions will help you make the most of your time together. List your questions from most important to least important in case time runs out. For Huntington's disease, some basic questions to ask your doctor include:
- Are my signs and symptoms caused by Huntington's disease?
- Are there any other possible causes for my symptoms?
- What kinds of tests do I need to confirm the diagnosis?
- What treatments are available, and which do you recommend?
- What types of side effects can I expect from treatment?
- Are there any clinical trials available to me?
- What types of supportive care, such as occupational therapy, are available to me?
- Are there any dietary or activity restrictions that I need to follow?
- Will I be able to have children? What's my risk of passing it on to them?
- How long will I be able to live on my own?
- Are there any brochures or other printed material that I can take home with me? What Web sites do you recommend visiting?
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment any time you don't understand something.
What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to spend more time on. Your doctor may ask:
- When did you first begin experiencing symptoms?
- Have your symptoms been continuous, or intermittent?
- Has anyone in your family ever been diagnosed with Huntington's disease?
- Are you having trouble performing any daily tasks?
- Has anyone in your family died young?
- Is anyone in your family in a nursing home?
- Is anyone in your family fidgety or moving all the time?
- Do you feel sad all of the time?
Tests and diagnosis
During an initial evaluation, your doctor will:
- Perform a physical exam
- Ask about your medical history and your family medical history
- Ask about any recent emotional or intellectual changes
If your doctor suspects Huntington's disease, you'll likely:
- Undergo a psychiatric evaluation
- Meet with a genetic counselor to discuss the possibility of having a blood test to determine whether you have the defective gene
If you know that one of your parents had Huntington's, ask your doctor about genetic testing. Genetic testing is generally done in a setting where pre-test counseling and post-test support are available along with testing.
Your doctor may also suggest:
- Computerized tomography (CT)
- Magnetic resonance imaging (MRI)
These imaging tests can help your doctor identify any changes to your brain's structure and rule out other disorders.
Treatments and drugs
No satisfactory treatment is available to stop or reverse Huntington's disease. Some approaches can control signs and symptoms, but Huntington's disease eventually causes physical and mental disability. As the disease progresses, long-term nursing home care may be necessary.
Medications
Tetrabenazine (Xenazine) is the first medication to be specifically approved by the Food and Drug Administration for the treatment of the signs or symptoms of Huntington's. It helps reduce the jerky, involuntary movements of Huntington's disease by increasing the amount of dopamine available in the brain. Possible side effects include insomnia, drowsiness, nausea and restlessness. This medication isn't recommended for use in anyone with depression, especially anyone with suicidal thoughts.
Tranquilizers such as clonazepam (Klonopin) and antipsychotic drugs such as haloperidol and clozapine (Clozaril) can help control movements, violent outbursts and hallucinations. While these medications can be helpful, a common side effect is sedation, and in some cases, these medications may cause additional stiffness and rigidity.
Various medications, including fluoxetine (Prozac, Sarafem), sertraline (Zoloft) and nortriptyline (Pamelor), can help control depression and the obsessive-compulsive rituals that some people with Huntington's disease develop. Medications such as lithium (Eskalith, Lithobid) can help control extreme emotions and mood swings.
Side effects from many of the drugs used to treat the symptoms of Huntington's disease may include hyperexcitability, fatigue and restlessness.
Speech therapy
Huntington's disease can impair your speech, affecting your ability to express complex thoughts. You may find that speech therapy helps. Remind friends, family members and caregivers that if you don't speak, it doesn't necessarily mean that you don't understand what's going on. Ask people to continue talking to you and keep your environment as normal as possible.
Physical and occupational therapy
Physical therapy can help keep muscles stronger and more flexible, which helps maintain balance and may lessen the risk of falling. Occupational therapy can help make your home safer and give you strategies for coping with memory and concentration problems. Later in the disease, occupational therapy can assist you with eating, dressing and hygiene challenges.
Experimental treatments and new research
Scientists are working to try to come up with new treatments to slow the course of Huntington's disease. One area of research is the combination of certain cancer and AIDS drugs. This combination has halted the progress of Huntington's in fruit flies.
The use of stem cells is another avenue for research. Transplanted in the brain, stem cells might help reduce some of the damage that's been done to the neurons in the brain. Animal studies have shown promising results, but much more research must occur.
In October 2008, researchers began recruiting for a randomized, placebo-controlled clinical trial of a new drug currently known as ACR16. This medication stabilizes levels of dopamine, which may improve motor, cognitive and psychiatric functioning.
Lifestyle and home remedies
Having Huntington's disease presents a number of challenges that require daily or regular attention. The following steps may improve how you feel:
- Exercise regularly. Regular exercise is beneficial. It helps both your physical and emotional health. Wearing well-fitting, sturdy shoes during exercise may help improve your stability.
- Maintain proper nutrition. You may burn as many as 5,000 calories a day, so be sure to get adequate nutrition to maintain your body weight, and consider extra vitamins and supplements. Because Huntington's disease can impair coordination, you may need assistance when eating. Give yourself as much time as you need for meals. Cutting food into small pieces or eating pureed food may make swallowing easier and prevent choking. Dairy products may make you secrete excess mucus, which may increase your risk of choking. Occupational therapists may make other suggestions on how to improve your swallowing. Using cups with lids and suction cups and tableware designed for people with disabilities may help prevent spills.
- Drink plenty of fluids. Huntington's disease can make you vulnerable to dehydration. Drink large amounts of liquids, especially during hot weather. Some people find that bendable straws make drinking easier.
Coping and support
From deciding whether to test for the Huntington's gene to planning for the day you can no longer care for yourself, Huntington's disease presents significant emotional challenges.
Some issues you'll have to deal with include:
- Legal matters. Because Huntington's disease affects your cognitive abilities, you'll need to draw up wills and living wills early in the course of the disease. Knowing that your loved ones know your end-of-life wishes can give you peace of mind.
- Arranging daily living assistance. Most people with Huntington's disease eventually need assistance in performing daily functions. You may want to live on your own but can't take care of tasks necessary for independent living. In these cases, group housing can provide a safe and comfortable living situation that allows you to maintain your independence.
- Emotional help. Depression is common in Huntington's disease. Don't hesitate to ask your doctor about treatment or for a referral to a mental health provider. Your doctor may also know if there's a Huntington's disease support group in your area. Talking with other people who have Huntington's may help you feel less alone, and you may get some useful tips on living with your disease. The Huntington's Disease Society of America can also let you know if there's a support group in your area. They can be reached at 800-345-4372.
Tips for caregivers
If you're a family member or friend of someone with Huntington's disease, caregiving can be time-consuming and exhausting. But certain resources can make caregiving easier. Hiring someone to help with household duties or with the physical care of the person with Huntington's disease is one option. In addition, many local, state and federal health agencies provide such assistance as meal programs, occupational therapy, nursing assistance and other services.
If you're a caregiver, take time to relax and take care of your own health. Therapeutic recreation and work centers can provide a place for someone with Huntington's disease to interact with others and pursue interests and activities, while also providing home caregivers a break.
Some cases of Huntington's disease may progress to the point where friends and family members can no longer provide adequate care. Long term care facilities can provide a safe and comfortable living situation when living at home isn't a viable option.
Prevention
If you have a family history of Huntington's disease, you may want to consider genetic counseling before starting a family. A blood test can determine the presence of the faulty gene, even before you show signs or symptoms. If one parent carries the defective gene, his or her child has a 50 percent chance of developing Huntington's disease.
If you're at risk of passing the genetic defect that causes Huntington's disease to your children, you may wish to consider adoption or certain forms of assisted reproduction. One possibility is in vitro fertilization with pre-implantation screening. In this procedure, embryos are screened for the Huntington's disease gene mutation, and those that don't have the mutation are then implanted in the woman's uterus.
- Huntington's disease: Hope through research. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/huntington/detail_huntington.htm. Accessed March 27, 2009.
- Huntington's disease. The Merck Manuals Online Medical Library: The Merck Manual for Healthcare Professionals. http://www.merck.com/mmpe/sec16/ch221/ch221e.html#sec16-ch221-ch221e-49. Accessed March 27, 2009.
- SuttonBrown MA, et al. Huntington disease: Clinical features and diagnosis. http://uptodate.com/home/index.html. Accessed March 12, 2009.
- Learning about Huntington's disease. National Human Genome Research Institute. http://www.genome.gov/page.cfm?pageID=10001215. Accessed March 27, 2009.
- Trushina E, et al. Mutant huntingtin inhibits clathrin-independent endocytosis and causes accumulation of cholesterol in vitro and in vivo. Human Molecular Genetics. 2006;15:3578.
- Katsuno M, et al. Getting a handle on Huntington's disease: The case for cholesterol. Nature Medicine. 2009;15:253.
- FDA approves first drug for treatment of chorea in Huntington's disease. U.S. Food and Drug Administration. http://www.fda.gov/bbs/topics/NEWS/2008/NEW01874.html. Accessed March 28, 2009.
- Kim SU. Stem cell-based cell therapy in neurological diseases: A review. Journal of Neuroscience Research. In press. Accessed March 28, 2009.
- ACR16. Neurosearch.com. http://www.neurosearch.com/Default.aspx?ID=752. Accessed March 28, 2009.
