What is ataxia?
Ataxia is the term for a group of neurological diseases (diseases related to the nervous system) that affect movement and coordination. People with ataxia often have trouble with balance, coordination, swallowing, and speech. Ataxia usually develops as a result of damage to a part of the brain that coordinates movement (cerebellum).
Ataxia can develop at any age. It is typically progressive, meaning it can get worse with time. It is a rare condition, affecting about 150,000 people in the U.S.
What are the different types of ataxia?
There are many different types of ataxia. The symptoms and their reason for developing determine the classification. Knowing the type can help doctors evaluate the condition and define a treatment plan.
- Ataxia telangiectasia (AT): Also known as Louis-Bar Syndrome, AT is an inherited condition. It typically develops in babies or young children. A common symptom of this type of ataxia is the appearance of enlarged (dilated) blood vessels known as telangiectasias in the eyes and on the skin of the face. Children with AT have symptoms including increasing difficulty walking, coordinating movements, looking from side to side, and trouble speaking. AT can weaken the immune system. People with the condition are more likely to get other illnesses, including infections and cancers.
- Episodic ataxia: With episodic ataxia, people have recurring troubles with movement and balance. These episodes can happen multiple times per day, or just one or two times a year. Episodic ataxia can develop at any age. Its causes include stress, medications, alcohol, illness, and physical exertion. There are seven types of episodic ataxia, all of which have unique symptoms in addition to difficulty with movement, including dizziness, headaches, blurry vision, and nausea and vomiting.
- Friedreich’s ataxia: In addition to worsening movement problems, people with Friedreich’s ataxia experience stiff muscles and gradually lose strength and feeling in their arms and legs. People with this type of ataxia often also have a heart condition that weakens the heart muscle (hypertrophic cardiomyopathy). Friedreich’s ataxia is the most common type of genetic ataxia. It typically develops between ages 5 and 15.
- Multiple system atrophy (MSA): MSA is a form of parkinsonism that affects movement and the part of your nervous system that controls involuntary body functions (autonomic nervous system). These functions include things such as regulating your blood pressure and urinary control. The most common symptoms of MSA include difficulty coordinating movements, a rapid blood pressure drop when you stand up, trouble urinating, and, in men, erectile dysfunction. MSA typically develops in adults aged 30 and older. The average age of onset is 54 years old.
- Spinocerebellar ataxia: Spinocerebellar ataxia is a genetic ataxia that is classified into dozens of different types, which are differentiated based on the associated features aside from ataxia. In addition to the typical movement and balance problems associated with ataxia, people with this condition tend to develop weakness and loss of sensation, and some types cause difficulty with eye movements. Symptoms of spinocerebellar ataxia can develop at any age. It often progresses more slowly than other types of ataxia.
What causes ataxia?
Ataxia develops when there is damage to the cerebellum (the part of the brain that coordinates movement). There are numerous causes of ataxia, either due to an acute injury or infection, or a chronic degenerative process.
Doctors and researchers classify ataxia into three main categories based on what they know about the cause. These categories are:
- Acquired ataxia: Caused by external factors including trauma, vitamin deficiencies, exposure to alcohol or drugs, infections, or cancers.
- Genetic ataxia: Occurs when a person has a damaged gene that is passed down among family members.
- Idiopathic ataxia: Doctors cannot determine the cause of the condition.
What are the symptoms of ataxia?
The symptoms of ataxia depend on the type of the condition a person has. In most cases, people with ataxia appear “clumsy.” Symptoms can include:
- Decreasing coordination
- Trouble walking
- Impaired balance with frequent falls
- Heart problems
- Loss of fine motor skills
- Muscle tremors
- Slurred speech
- Vision problems