Health Library

Huntington's Disease

(Huntington Chorea; HD)

Definition

Huntington's disease (HD) is an inherited disorder that affects the brain. HD causes slow, progressive degeneration of nerve cells in certain areas of the brain. Eventually, HD results in:

Abnormal body movements

Gradual deterioration or loss of intellectual abilities (dementia)
Behavior problems

Causes

A faulty gene on chromosome #4 causes HD. All people who inherit the faulty gene may eventually develop HD.

Risk Factors

These factors increase your chance of developing HD:

Family members with HD: Each person whose parent has HD has a 50% chance of inheriting the disorder.
Age: Onset of symptoms range from 35-50 years old. Juvenile cases occur in people less than 20 years of age.

Symptoms

Symptoms are mild at first and are often barely noticeable but usually worsen over 15-20 years.

Physical symptoms may include:

Abnormal body movements that worsen over time, including:
- Sudden jerks or uncontrolled movements of the limbs or trunk
- Facial grimacing
- Continuous need to turn head and shift gaze
- Walking that is unsteady or dance-like
Difficulty with eating, dressing, sitting, and caring for oneself
Difficulty swallowing
Grunting or poor articulation of speech
Weight loss

Intellectual and emotional symptoms may include:

Trouble with attention and awareness

Confusion or disorientation

Loss of memory

Loss of judgment

Loss of ability to think rationally

Irritability and moodiness

Depression (common)
Anxiety
Social withdrawal or antisocial behavior
Irresponsible behavior
Obsessive-compulsive behavior
Personality changes
Psychosis—a severe emotional and behavioral disorder that often interferes with a person's ability to relate to others and to function in daily life
Paranoia—a mental disorder that involves feelings of being watched, followed, or harmed by others
Hallucinations—the perception of a thing or person that is not present

Ultimately, HD can:

Cause the loss of the physical and mental ability to care for oneself
Cause severe disability, making full-time or nursing home care necessary
Result in death, often due to a fall or pneumonia

Diagnosis

The doctor will ask about your symptoms and medical history (including family medical history). A physical exam will be done. Tests may include:

Computed tomography (CT) scan—a type of x-ray that uses a computer to make pictures of the brain
Magnetic resonance imaging (MRI) scan—a test that uses magnetic waves to make pictures of the brain
Positron emission tomography (PET) scan—a test that uses radioactive isotopes (substances that are absorbed by certain areas of the brain) to assess brain function
Blood tests—to rule out other causes of symptoms

CT Scan of the Head

There is a test that can determine if a person has inherited the gene for HD. This test may help to make the diagnosis of HD. It may also help to determine if a person has inherited the HD gene before symptoms appear. Genetic counseling is recommended before taking this test to review risks and benefits.

Treatment

There is no cure for HD. Treatment aims to help control symptoms.

Drugs can help control abnormal movements and emotional symptoms of HD. These include:

Tetrabenazine
Sedatives or minor tranquilizers, such as benzodiazepines
Major tranquilizers, like haloperidol or phenothiazine
Antidepressants

Staying physically active helps people with HD to function better and longer. Often physical and occupational therapy may be of some benefit.

Prevention

There is no way to prevent the onset of HD if a person has inherited the gene for the disorder. Medicines aimed at slowing and treating the disease progression are being studied. A prospective parent with HD or a family history of HD can seek genetic counseling when deciding whether or not to have children. Genetic counseling is extremely important since children of parents with HD will have a 50% chance of inheriting the condition.

Hereditary Disease Foundation

http://www.hdfoundation.org/

Huntington Disease Society of America

http://www.hdsa.org/

International Huntington Association

http://www.huntington-assoc.com/

Health Canada

http://www.hc-sc.gc.ca/

Huntington Society of Canada

http://www.huntingtonsociety.ca/

Agarwal P. Huntington disease. MedLink Neurology website. Available at: http://www.medlink.com/medlinkcontent.asp. Accessed July 1, 2009.

Aminoff M. Nervous system disorders. McPhee S, Papadakis M, Tierney L. Current Surgical Diagnosis and Treatment. 12th ed. New York, NY: McGraw-Hill; 2003; chap 24.

Beers MH. The Merck Manual of Medical Information. 2nd ed. London, England: Simon and Schuster, Inc; 2003.

DynaMed Editorial Team. Huntington disease. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed/what.php. Updated July 9, 2010. Accessed November 17, 2010.

Mestre T, Ferreira J, Coelho MM, et al. Therapeutic interventions for symptomatic treatment in Huntington's disease. Cochrane Database Syst Rev. 2009;8(3):CD006456.

NINDS Huntington's Disease information page. National Institute of Neurological Disorders and Stroke website. Available at: http://www.ninds.nih.gov/disorders/huntington/huntington.htm. Accessed July 1, 2009

Last reviewed September 2012 by Rimas Lukas, MD

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.