Huntington’s Disease (Chorea)

 

What Is It?

Huntington’s disease is an inherited disease that causes nerve cells in the brain to stop working properly. It is a progressive disease, meaning it continues to get worse over time, and leads to mental deterioration and loss of the ability to control major muscle movements.

An American doctor, George Huntington, first described Huntington’s disease in 1872. It was commonly called Huntington’s chorea from the Greek word for “dance,” because of the jerky, almost dancelike, movements of people with the disease.

The genetic abnormality that causes Huntington’s disease was discovered in 1993. Huntington’s disease is transmitted as an autosomal dominant disorder, meaning that each child of a parent with Huntington’s disease has a 50-percent chance of inheriting the illness. Huntington’s disease is relatively uncommon, affecting about one in every 10,000 people, or approximately 30,000 people in the United States.

Symptoms

Huntington’s disease can affect intellectual ability, movement and emotional control. Symptoms include:

  • Memory loss, inattention, dementia
  • Involuntary twitching, clumsiness, chorea (dance-like involuntary movements), slurred speech, difficulty walking, difficulty swallowing
  • Personality changes, depression, irritability, anxiety, apathy

Symptoms vary from person to person. They also can change over time, usually starting as subtle differences and progressing to profound disability. Symptoms typically begin between the ages of 35 and 50, though they can appear at any age.

The disease is rare in children. Symptoms begin before age 10 in less than 1 percent of cases. In children with Huntington’s disease, behavioral problems and mental deterioration are prominent, and rigidity and seizures are also common. Huntington’s disease progresses more rapidly in children than in adults.

Diagnosis

Someone with a family history of Huntington’s disease who begins to have symptoms often is diagnosed based on a physical and neurological exam. A blood test is now available to detect the presence of the genetic abnormality that causes Huntington’s disease. Everyone who carries the Huntington’s disease gene eventually will develop the disease, but the test cannot predict when symptoms will begin.

Genetic testing carries enormous emotional and practical consequences, and you should discuss these issues with your doctor. Some people chose to be tested in order to make informed decisions about future plans (for example, career or marriage). In some centers, prenatal testing can be done. If you have a family history of Huntington’s disease, you should seek genetic counseling before getting pregnant to determine your risk of passing the gene to your children.

Many experts recommend that children under 18 should not be tested, except in rare cases where there is an urgent medical need to do so. It is better to wait until children turn 18 so they can make their own decisions whether to learn if they have the gene for Huntington’s.

Expected Duration

The genetic abnormality that causes Huntington’s disease is present from birth. Symptoms typically begin in mid-life and persist until the end of life.

Prevention

There is no way to prevent this disease in people who have inherited the genetic abnormality.

Treatment

There is no therapy to cure Huntington’s disease or to slow its progression. However, there are treatments, including speech therapy and physical therapy, which can lessen the severity of symptoms. Antidepressants, neuroleptics and other medications can help to control mood and involuntary movements.

When To Call A Professional

If you have a family history of Huntington’s disease, discuss this with your doctor. You may want to consider genetic testing to determine whether you carry the Huntington’s disease gene. You also may want to understand the risks involved before having children.

Call your doctor if you experience any problems with emotional control, intellectual ability or movement. These symptoms are not specific to Huntington’s disease, and if you don’t have a family history of the disease, they are more likely to be symptoms of other conditions.

Prognosis

Although there is no therapy to halt the progression of Huntington’s disease, the course of the disease varies from person to person. For example, some people have mild symptoms that progress slowly while others have severe symptoms at a young age. There is some evidence that people who exercise and remain active tend to have milder symptoms and slower disease progression than those who do not. However, everyone with Huntington’s disease ultimately becomes severely debilitated. They have difficulty eating and swallowing and are susceptible to infection. For adults, the time from the beginning of symptoms until death is usually 15 to 20 years. In children, the disease progresses more rapidly, with an average of eight years from the onset of symptoms until death. Research efforts toward a cure have intensified since identification of the gene for Huntington’s disease.

Johns Hopkins patient information

Last revised:

Diseases and Conditions Center

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All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.