Ataxia is a loss of coordination in the arms, legs, fingers, face or other part of the body as a result of damage to the cerebellum or spinal cord. The cerebellum is the part of the brain responsible for coordination and movement. People who experience ataxia may have trouble walking, coordinating precise movements, moving the eyes efficiently or speaking clearly. They may also exhibit symptoms such as aphasia, apraxia or tremors. Severe ataxia may result in swallowing problems, which can lead to additional complications.
Ataxia is a symptom rather than a disease. However, the term ataxia may also be used to describe disorders where the primary symptom is ataxia. Examples of ataxia disorders are spinocerebellar ataxia, Friedreich’s ataxia and ataxia telangiectasia. These disorders are hereditary and have no known cure.
Ataxia can be caused by anything that disrupts the function of the cerebellum. Some factors that may cause ataxia include:
- Head injury
- Alcohol abuse
Treatment for ataxia typically addresses the underlying condition, which usually eliminates the ataxia. In some cases, severe damage to the cerebellum may result in permanent or degenerative ataxia. Although ataxia itself cannot be prevented, taking steps to stabilize blood pressure, eating a healthy diet and reducing or moderating alcohol consumption may help prevent many of the conditions that can cause ataxia.
Ataxia is a loss of coordination in the arms, legs, fingers, face or body in general. It is a neurological (nervous system) symptom rather than a muscular one. It results in clumsiness and may also affect eye movements and the ability to speak. Ataxia is also the name given to a group of disorders whose characterizing symptom is ataxia.
Ataxia is usually the result of damage to the cerebellum, either through injury or a degenerative disease. The cerebellum, located at the rear of the brain between the brain stem and the cerebral cortex, is responsible for coordination and aspects of skilled movement. It also helps control the force and range of muscular contractions. In some cases, ataxia can also be caused by damage to the spinal cord.
People experiencing ataxia may have difficulty walking steadily (also known as unsteady gait), which they may compensate for by placing the feet far apart when walking. They may also experience problems making precise movements. For example, they may lack the coordination required to pick up an object or button up a shirt. Ataxia may also affect eye movement, resulting in problems fixating on objects or following movement smoothly with the eyes.
Ataxia that affects vocal ability may result in slurred speech. It may also lead to “scanning” speech in which words are spoken slowly with long pauses in between each syllable. Additionally, ataxia may affect the ability to swallow (called dysphagia), which can lead to pneumonia if saliva or food particles are aspirated (inhaled) into the lungs.
People may experience some or all of the effects of ataxia. If the damage to the cerebellum is localized to a specific area, the patient may experience isolated effects (e.g. problems walking or speaking with no other signs of ataxia). Widespread damage to the cerebellum is likely to result in ataxia in numerous parts of the body. In some cases, ataxia clears of its own accord once the underlying condition has been treated. However, sometimes ataxia is a symptom of a permanent or degenerative condition (e.g., multiple sclerosis) and the ataxia may get worse over time. People with severe ataxia may have difficulty living independently and may require the assistance of a caregiver.
Other symptoms related to ataxia
People who experience ataxia as a symptom often experience it in conjunction with other symptoms, which may be related to other neurological damage caused by an underlying condition. Some symptoms that may accompany ataxia include:
- Aphasia. Loss of the ability to use and understand language. It is the result of damage to the part of the brain that is associated with language, which, for the vast majority of people, is the left side of the brain. Some people describe aphasia as being similar to visiting a foreign country and being surrounded by people speaking a language that is not understood.
- Apraxia. A neurological symptom that results in an inability to perform purposeful movements on demand. People with apraxia are not physically paralyzed, but they lack the ability to control the muscles required to perform tasks. It is usually the result of damage to the parietal lobe of the brain, which is associated with planning and executing movements.
- Tremors. Involuntary, usually rhythmic muscle movements. These movements occur in a to-and-fro fashion (oscillations) and affect one or more parts of the body. Tremors most frequently affect a person’s hands, but may also affect the arms, head, face, vocal cords, trunk and legs. People with ataxia may develop a tremor as the cerebellum attempts to correct coordination problems.
Ataxia disorders are disorders characterized by ataxia as the primary symptom. Most ataxia disorders are hereditary and are caused by defective genes. It may be difficult to clinically distinguish one from another as each disorder has similar symptoms. Ataxia disorders are often classified as pediatric disorders because the symptoms may appear at birth. However, symptoms may also develop in adolescence, early adulthood or even middle-age. Some types of ataxia disorders include:
- Friedreich’s ataxia. Atrophy of the upper spinal cord and cerebellum, resulting in ataxia, heart disease, scoliosis and, in some cases, diabetes. Friedreich’s ataxia is an autosomal recessive disorder, which means that both parents must carry the abnormal gene for the disorder to be passed to a child. The chances that a child will inherit Friedreich’s ataxia if both parents carry the abnormal gene are roughly 1 in 4, according to the National Institute of Neurological Disorders and Stroke (NINDS). There is a higher chance (1 in 2), that the child will inherit one abnormal gene, and may pass the gene to future generations.
Symptoms of Friedreich’s ataxia tend to develop in childhood and early adolescence, although some people may not experience symptoms until they are older. The progression of the disease is often aggressive, with some people incapacitated within 20 years of the onset of symptoms. Most people with Friedreich’s ataxia die from the heart disease that commonly accompanies the disease.
- Spinocerebellar ataxia (SCA). Atrophy (wasting) of the cerebellum, resulting primarily in ataxia but sometimes also causing symptoms such as dizziness, seizures and blindness. There may be as many as 28 types of SCA, which are categorized according to the location of the defective gene. The symptoms of some SCAs begin to develop in middle-age and may degenerate over the following 10 to 20 years. Other SCAs show symptoms from birth and may be relatively mild. SCAs are autosomal dominant disorders, which means that only one parent must carry the abnormal gene for the disorder to be passed to a child. The most common form of SCA is Machado-Joseph disease (or SCA3).
- Ataxia telangiectasia. A disorder characterized by ataxia and the presence of small, red veins (telangiectasias) on the skin of the cheeks, ears and in the whites of the eyes. Like Friedreich’s ataxia, ataxia telangiectasia is an autosomal recessive disorder. Symptoms usually begin to appear in early childhood and may progress rapidly. Roughly 20 percent of children with ataxia telangiectasia develop cancer, usually lymphomas or leukemias. People with ataxia telangiectasia frequently have a compromised immune system, resulting in repeated infections, according to NINDS. Most people with ataxia telangiectasia die by their early 20s.
Most ataxia disorders have no cure, and treatment is mainly supportive. Patients may be able to use adapted devices (e.g. walking aids, communication devices) aimed at allowing the patient to remain independent for as long as possible. Additionally, complications or accompanying conditions (such as diabetes or heart disease) may be treated to improve the patient’s quality of life.
Potential causes of ataxia
Ataxia can be caused by anything that disrupts the cerebellum, which is the part of the brain responsible for coordination and movement. In many cases, the ataxia may be resolved following the treatment of the underlying cause. Sometimes, ataxia can occur suddenly in an individual. This may be the result of a variety of factors, including:
- Stroke. A stroke occurs when a blood vessel in the brain bursts or becomes clogged by a blood clot or other mass (e.g., blood cholesterol). This prevents oxygen and nutrients from traveling to nerve cells in the affected area of the brain. These nerve cells can die within minutes, and the area of the body that they control can cease to function.
- Head injury. A head injury that damages the cerebellum can result in ataxia, along with numerous other symptoms. In some cases, the ataxia may be temporary. However, severe head injuries may result in permanent ataxia.
- Tumors or lesions. Brain tumors or lesions, which can cause pressure to build in the brain, can disrupt the function of neurons. This can lead to ataxia, which may come on suddenly or gradually. In some cases, removal of the tumor or lesion may resolve the problem, although sometimes the damage is permanent. In rare cases, tumors in the breast, ovaries or lungs can cause an abnormal immune response (called paraneoplastic syndrome) that may also result in ataxia.
- Infection. There are several infections that may affect the brain and cause ataxia. Diseases such as meningitis, encephalitis or chickenpox can disrupt the function of the brain during and after the infection. Ataxia that develops after an infection is known as “post-infectious” ataxia and often resolves itself after a period of time.
In some cases, ataxia may develop gradually. This may be caused by an ataxia disorder such as Friedreich’s disease or spinocerebellar ataxia. Another progressive neurological disorder, multiple system atrophy, can also cause ataxia. However, it is more often the result of an underlying condition, such as:
- Hypothyroidism. Also called an underactive thyroid, hypothyroidism is a disorder in which the thyroid gland does not produce enough thyroid hormone to meet the body’s needs. A lack of thyroid hormone can cause a variety of symptoms affecting most of the body’s major systems.
- Alcohol abuse. Chronic alcohol abuse may lead to a degeneration of the cerebellum, resulting in ataxia, among other symptoms. Stopping drinking may improve ataxia. Continued alcohol abuse can result in a progressive worsening of ataxia.
- Vitamin deficiency. The B vitamins, especially thiamine and B12, are most commonly associated with the development of ataxia. A B-vitamin deficiency can result from poor diet or disorders that prevent vitamins from being absorbed effectively into the bloodstream. These vitamins are often deficient in alcoholics because alcohol interferes with the absorption of thiamine. Vitamin E deficiency can also cause ataxia.
- Medications. Certain medications, such as anti-seizure medications, lithium, barbiturates (sedatives), anticholinergics and chemotherapy drugs may cause patients to develop ataxia. In most cases, changing the type of medication resolves the ataxia.
- Poisoning. Some heavy metals (e.g. mercury, thallium, lead) can cause ataxia if they are absorbed into the body. Additionally, consumption or contact with certain plants (e.g., poison hemlock, the chinaberry tree), inhaling nitrous oxide, or sniffing glue or gasoline may cause ataxia.
- Multiple sclerosis (MS). MS is a neurological disorder that may cause symptoms ranging from mild to severe in intensity. As the disease progresses, most patients experience ataxia in various parts of the body. A third of MS patients may eventually be paralyzed by the disease. The life span of patients with MS is slightly shorter, but rarely significantly different from the rest of the population.
- Syphilis. Syphilis is an infectious disease, usually spread through unprotected sexual contact. Symptoms of the disease appear in readily identifiable stages, but not all people progress through each stage. During the final (tertiary) stage of syphilis, the infection may affect many parts of the nervous system, including the meninges, brain and spinal cord. This may result in ataxia.
Treatment and prevention of ataxia
In many cases, treatment of the underlying cause of ataxia may resolve the problem. However, in some instances, damage to the brain may be permanent. There are few options to treat ataxia directly. People with ataxia may find that devices such as walking aids and communication devices enable them to live independently for a longer period of time. Some people with mild ataxia may benefit from speech or physical therapy.
An important lifestyle consideration for the patient is the education of the patient’s family and friends. Caregivers and others should be aware of the nature of the patient’s limitations and be educated about how to communicate with the patient, especially if the patient experiences verbal problems. People with ataxia may become dependent on caregivers for many aspects of daily life.
Ataxia as a symptom cannot be prevented. However, it may be possible to protect the body against some of the causes of ataxia. For instance, maintaining a normal blood pressure level, eating a healthy, balanced diet and moderating alcohol consumption may significantly reduce the risk of developing many of the conditions that can result in ataxia. Additionally, people should protect their head from injury by taking suitable precautions while traveling in a vehicle, riding a motorcycle or bicycle and playing contact sports.
Questions for your doctor regarding ataxia
Preparing questions in advance can help patients to have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following ataxia-related questions:
- What is causing my ataxia?
- How will you treat my underlying condition?
- Are there any over-the-counter medications I can take to help my ataxia?
- Is my ataxia reversible?
- Should I make any lifestyle changes to reduce my risk of worsening my ataxia?
- Do I have a genetic ataxia disorder?
- If I have ataxia, are my children also at risk for ataxia?
- Will my ataxia get worse?
- Should I consult a physical or speech therapist? Can you recommend one?
- Will I have to move into a long term care facility?