Huntington Disease
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 wide impact on a person's functional abilities and usually results in movement, thinking (cognitive) and psychiatric disorders.
Inheritance
Every cell in your body has DNA (deoxyribonucleic acid). DNA is your body’s instruction manual. It provides the information you need to repair and rebuild cells. Your DNA dictates everything from your hair color and height to how your organs function.
Genes are like chapters within the DNA instruction manual. Here’s how genes affect Huntington’s disease:
The huntingtin gene (HTT or HD gene) tells your body how to build the huntingtin protein. You get one HTT gene from each parent.
If you have Huntington’s disease, one of your parents passed on an HTT gene with a mutation (like a misprint in a book). It tells your body to create an unusually long protein. Researchers believe this long protein damages and kills brain cells.
Anyone who inherits the gene will eventually develop HD symptoms. The exact age when symptoms appear varies. Often, HD symptoms start earlier in each new generation than in the previous generation.
Symptoms
Uncontrolled movements (chorea).
Emotional changes like mood swings, depression and irritability.
Problems with memory, focus and multitasking.
Slowed movements and speech.
Slurred speech.
Loss of hand coordination, such as being unable to hold a pencil.
Difficulty swallowing.
Diagnosis
You will have tests to rule out other conditions that cause similar symptoms and to confirm an HD diagnosis. Tests include:
Blood test.
Genetic testing.
Imaging tests such as magnetic resonance imaging (MRI) and computed tomography (CT) scan.
Stages of progression
Early stage
Symptoms are easier to handle early in the disease. You might feel moody or clumsy and struggle with complex thinking. You may also have small uncontrollable movements, but typically, you can continue your everyday activities.
Middle stage
Physical and mental changes during the middle stage make working, driving and household upkeep impossible. You may begin to have trouble with swallowing, and you might lose weight. Your balance may be off, increasing your risk of falling.
You can still manage your personal care. Typically, you can handle bathing, getting dressed and eating on your own or with some help.
End stage
During the final stage of HD, you’ll need help with everything. You’re usually unable to leave bed. This is when most people receive care day and night.
Prevention
Get regular exercise: Research shows exercise helps reduce symptoms.
Eat a healthy diet: You may need extra nutrition. People can burn up to 5,000 calories a day through unintended movements.
Drink plenty of water: When swallowing becomes difficult, you can easily become dehydrated.
Find a support group: Ask your doctor for community resources where you can connect with others affected by the disease.
Research care services: At some point, you’ll need a high level of care from either home care services or a nursing home.
Appoint a trusted advisor: As the disease progresses, you’ll have to pass financial duties and important decision-making to someone else.
Treatment
To control chorea, doctors commonly prescribe:
Tetrabenazine.
Deutetrabenazine.
Haloperidol.
To help with emotional symptoms, your doctor may recommend:
Antidepressants: Drugs that relieve depression include fluoxetine (Prozac®, Sarafem®) and sertraline (Zoloft).
Antipsychotic drugs: To reduce angry outbursts, agitation and hallucinations, your doctor may recommend drugs such as risperidone (Risperdal) and olanzapine (Zyprexa).
Mood-stabilizing drugs: Medications like lithium (Eskalith) decrease anxiety and prevent severe mood swings.