This condition causes a progressive breakdown of nerve cells in the brain. Find out about what signs to watch for and how treatments may help.
Huntington's disease is a rare, inherited disease that causes the progressive breakdown (degeneration) of nerve cells in the brain. Huntington's disease has a broad impact on a person's functional abilities and usually results in movement, thinking (cognitive) and psychiatric disorders.
Huntington's disease symptoms can develop at any time, but they often first appear when people are in their 30s or 40s. If the condition develops before age 20, it's called juvenile Huntington's disease. When Huntington's develops early, symptoms are somewhat different and the disease may progress faster.
Medications are available to help manage the symptoms of Huntington's disease. But treatments can't prevent the physical, mental and behavioral decline associated with the condition.
Huntington's disease usually causes movement, cognitive and psychiatric disorders with a wide spectrum of signs and symptoms. Which symptoms appear first varies greatly from person to person. Some symptoms appear more dominant or have a greater effect on functional ability, but that can change throughout the course of the disease.
The movement disorders associated with Huntington's disease can include both involuntary movement problems and impairments in voluntary movements, such as:
Impairments in voluntary movements — rather than the involuntary movements — may have a greater impact on a person's ability to work, perform daily activities, communicate and remain independent.
Cognitive impairments often associated with Huntington's disease include:
The most common psychiatric disorder associated with Huntington's disease is depression. This isn't simply a reaction to receiving a diagnosis of Huntington's disease. Instead, depression appears to occur because of injury to the brain and subsequent changes in brain function. Signs and symptoms may include:
Other common psychiatric disorders include:
In addition to the above disorders, weight loss is common in people with Huntington's disease, especially as the disease progresses.
The start and progression of Huntington's disease in younger people may be slightly different from that in adults. Problems that often present early in the course of the disease include:
See your doctor if you notice changes in your movements, emotional state or mental ability. The signs and symptoms of Huntington's disease can be caused by a number of different conditions. Therefore, it's important to get a prompt, thorough diagnosis.
Huntington's disease is caused by an inherited defect in a single gene. Huntington's disease is an autosomal dominant disorder, which means that a person needs only one copy of the defective gene to develop the disorder.
With the exception of genes on the sex chromosomes, a person inherits two copies of every gene — one copy from each parent. A parent with a defective gene could pass along the defective copy of the gene or the healthy copy. Each child in the family, therefore, has a 50% chance of inheriting the gene that causes the genetic disorder.
After Huntington's disease starts, a person's functional abilities gradually worsen over time. The rate of disease progression and duration varies. The time from disease emergence to death is often about 10 to 30 years. Juvenile Huntington's disease usually results in death within 10 years after symptoms develop.
The clinical depression associated with Huntington's disease may increase the risk of suicide. Some research suggests that the greater risk of suicide occurs before a diagnosis is made and in the middle stages of the disease when a person starts to lose independence.
Eventually, a person with Huntington's disease requires help with all activities of daily living and care. Late in the disease, he or she will likely be confined to a bed and unable to speak. Someone with Huntington's disease is generally able to understand language and has an awareness of family and friends, though some won't recognize family members.
Common causes of death include:
People with a known family history of Huntington's disease are understandably concerned about whether they may pass the Huntington gene on to their children. These people may consider genetic testing and family planning options.
If an at-risk parent is considering genetic testing, it can be helpful to meet with a genetic counselor. A genetic counselor will discuss the potential risks of a positive test result, which would indicate that the parent will develop the disease. Also, couples will need to make additional choices about whether to have children or to consider alternatives, such as prenatal testing for the gene or in vitro fertilization with donor sperm or eggs.
Another option for couples is in vitro fertilization and preimplantation genetic diagnosis. In this process, eggs are removed from the ovaries and fertilized with the father's sperm in a laboratory. The embryos are tested for presence of the Huntington gene, and only those testing negative for the Huntington gene are implanted in the mother's uterus.
A preliminary diagnosis of Huntington's disease is based primarily on your answers to questions, a general physical exam, a review of your family medical history, and neurological and psychiatric examinations.
The neurologist will ask you questions and conduct relatively simple tests of your:
The neurologist may also perform standardized tests to check your:
You'll likely be referred to a psychiatrist for an examination to look for a number of factors that could contribute to your diagnosis, including:
Your doctor may order brain-imaging tests for assessing the structure or function of the brain. The imaging technologies may include MRI or CT scans that show detailed images of the brain.
These images may reveal changes in the brain in areas affected by Huntington's disease. These changes may not show up early in the course of the disease. These tests can also be used to rule out other conditions that may be causing symptoms.
If symptoms strongly suggest Huntington's disease, your doctor may recommend a genetic test for the defective gene.
This test can confirm the diagnosis. It may also be valuable if there's no known family history of Huntington's disease or if no other family member's diagnosis was confirmed with a genetic test. But the test won't provide information that might help determinine a treatment plan.
Before having such a test, the genetic counselor will explain the benefits and drawbacks of learning test results. The genetic counselor can also answer questions about the inheritance patterns of Huntington's disease.
A genetic test can be given if you have a family history of the disease but don't have symptoms. This is called predictive testing. The test can't tell you when the disease will begin or what symptoms will appear first.
Some people may have the test because they find not knowing to be more stressful. Others may want to take the test before having children.
Risks may include problems with insurability or future employment and the stresses of facing a fatal disease. In principle, federal laws exist that make it illegal to use genetic testing information to discriminate against people with genetic diseases.
These tests are only performed after consultation with a genetic counselor.
No treatments can alter the course of Huntington's disease. But medications can lessen some symptoms of movement and psychiatric disorders. And multiple interventions can help a person adapt to changes in his or her abilities for a certain amount of time.
Medications will likely evolve over the course of the disease, depending on overall treatment goals. Also, drugs that treat some symptoms may result in side effects that worsen other symptoms. Treatment goals will be regularly reviewed and updated.
Drugs to treat movement disorders include the following:
Antipsychotic drugs, such as haloperidol (Haldol) and fluphenazine, have a side effect of suppressing movements. Therefore, they may be beneficial in treating chorea. However, these drugs may worsen involuntary contractions (dystonia), restlessness and drowsiness.
Other drugs, such as risperidone (Risperdal), olanzapine (Zyprexa) and quetiapine (Seroquel), may have fewer side effects but still should be used with caution, as they may also worsen symptoms.
Medications to treat psychiatric disorders will vary depending on the disorders and symptoms. Possible treatments include the following:
A psychotherapist — a psychiatrist, psychologist or clinical social worker — can provide talk therapy to help with behavioral problems, develop coping strategies, manage expectations during progression of the disease and facilitate effective communication among family members.
Huntington's disease can significantly impair control of muscles of the mouth and throat that are essential for speech, eating and swallowing. A speech therapist can help improve your ability to speak clearly or teach you to use communication devices — such as a board covered with pictures of everyday items and activities. Speech therapists can also address difficulties with muscles used in eating and swallowing.
A physical therapist can teach you appropriate and safe exercises that enhance strength, flexibility, balance and coordination. These exercises can help maintain mobility as long as possible and may reduce the risk of falls.
Instruction on appropriate posture and the use of supports to improve posture may help lessen the severity of some movement problems.
When the use of a walker or wheelchair is required, the physical therapist can provide instruction on appropriate use of the device and posture. Also, exercise regimens can be adapted to suit the new level of mobility.
An occupational therapist can assist the person with Huntington's disease, family members and caregivers on the use of assistive devices that improve functional abilities. These strategies may include:
Managing Huntington's disease is demanding on the person with the disorder, family members and other in-home caregivers. As the disease progresses, the person will become more dependent on caregivers. A number of issues will need to be addressed, and strategies to cope with them will evolve.
Factors regarding eating and nutrition include the following:
Eventually, a person with Huntington's disease will need assistance with eating and drinking.
Family and caregivers can help create an environment that may help a person with Huntington's disease avoid stressors and manage cognitive and behavioral challenges. These strategies include:
A number of strategies may help people with Huntington's disease and their families cope with the challenges of the disease.
Support services for people with Huntington's disease and families include the following:
Because Huntington's disease causes the progressive loss of function and death, it's important to anticipate care that will be needed in the advanced stages of the disease and near the end of life. Early discussions about this type of care enable the person with Huntington's disease to be engaged in these decisions and to communicate his or her preferences for care.
Creating legal documents that define end-of-life care can be beneficial to everyone. They empower the person with the disease, and they may help family members avoid conflict late in the disease progression. Your doctor can offer advice on the benefits and drawbacks of care options at a time when all choices can be carefully considered.
Matters that may need to be addressed include:
If you have any signs or symptoms associated with Huntington's disease, you'll likely be referred to a neurologist after an initial visit to your family doctor.
A review of your symptoms, mental state, medical history and family medical history can all be important in the clinical assessment of a potential neurological disorder.
Before your appointment, make a list that includes the following:
You may want a family member or friend to accompany you to your appointment. This person can provide support and offer a different perspective on the effect of symptoms on your functional abilities.
Your doctor is likely to ask you a number of questions, including the following:
November 6th, 2021