Huntington's Disease

Huntington's disease (HD) is an inherited genetic disease that results in degeneration of nerve cells in in the brain, causing physical, mental, and psychiatric disorders.

The hallmark symptom of Huntington's disease (HD) is uncontrolled movement of the arms, legs, head, face and upper body. Those with Huntington's disease often experience alterations in mood such as depression, anxiety, and psychosis. Behavior changes usually occur before movement problems. As the disease progresses, the patient may have difficulty feeding himself or herself and swallowing.

Huntington disease is caused by a genetic defect on chromosome 4 and is passed down through families. The defect causes a part of DNA, called a CAG repeat, to occur many more times than normal.

Although there is not a cure for Huntington's disease, there are medications which can help manage some of the symptoms. These medications cannot slow down or stop the disease. Dopamine blockers may help reduce abnormal behaviors and movements. Drugs such as amantadine and tetrabenazine  are used to try to control extra movements.

The hallmark symptom of Huntington's disease (HD) is abnormal and unusual movements.

Those with Huntington's disease often experience alterations in mood such as depression, anxiety, mood swings, psychosis, hallucinations, paranoia, restlessness, and irritability. Behavior changes usually occur before movement problems.

Those with Huntington's disease (HD) may experience uncontrolled movement of the arms, legs, head, face and upper body. Other symptoms may include:

• Slow, uncontrolled movements
• Unsteady gait
• Facial movements, including grimaces
• Head turning to shift eye position

People with Huntington's disease may notice a decline in thinking and reasoning skills, including memory, concentration, judgment, and the ability to plan and organize. Some may experience speech changes.

As the disease progresses, the patient may have difficulty feeding himself or herself and swallowing.

Symptoms in children may include:

• Rigidity
• Slow movements
• Tremor

Huntington disease is caused by a genetic defect on chromosome 4 and is passed down through families. The defect causes a part of DNA, called a CAG repeat, to occur many more times than normal. Those with Huntington disease may have a repeat of 36 to 120 times compared to a normal repeat of 10 to 28 times.

The number of repeats tend to get larger as the gene is passed down through families. The larger the number of repeats, the higher the chance of developing symptoms at an earlier age. As the disease continues to pass down within the family, the symptoms typically develop at younger and younger ages.

Huntington's disease is passed from parent to child through a mutation in the normal gene. If a parent has Huntington's disease, each child has a 50-50 chance of inheriting the HD gene.

• If a child does not inherit the HD gene, he or she will not develop the disease and cannot pass it to subsequent generations.
• A person who inherits the HD gene will sooner or later develop the disease.

Your doctor will perform a physical exam and may ask you about your symptoms and family history. He/she will also perform an exam of the nervous system.

Huntington's disease may also be diagnosed based on the following exams:

• Psychological testing
• Head computed tomography (CT) or Magnetic resonance imaging (MRI) scan
• PET (isotope) scan of the brain

There is also genetic testing available to determine whether a person carries the gene for Huntington disease.

Those with Huntington's disease should engage in regular physical activity. Those who exercise and remain active tend to do better.

If a family has a history of Huntington's disease, genetic counseling is recommended. Experts also recommend genetic counseling for couples with a family history of this disease and who are considering having children.

Although there is not a cure for Huntington's disease, there are medications which can help manage some of the symptoms. These medications cannot slow down or stop the disease.

Your doctor will prescribe certain medications based on the symptoms you are experiencing which may include the following:

• Dopamine blockers may help reduce abnormal behaviors and movements.
• Drugs such as amantadine (Symmetrel) and tetrabenazine (Xenazine) are used to try to control extra movements.

If you are experiencing depression or other mental changes, your doctor may start treatment to manage those symptoms.

There is continued research on understanding the symptoms progression of Huntington's disease (HD), and how it causes disease in the human body.

Investigators are implanting fetal tissue in rodents and nonhuman primates with the hope of understanding, restoring, or replacing functions typically lost by neuronal degeneration in individuals with HD.

As the disease progresses, the person will usually need assistance and supervision, and may eventually need 24-hour care.

Huntington disease causes disability that gets worse over time. Persons with this disease usually die within 15 to 20 years. The cause of death is often infection.

Suicide is also a common cause of death. With that being said, it is important for caregivers to monitor for symptoms and seek medical help for the person right away if you notice they have thoughts of suicide or attempts to commit suicide.