What Is Friedreich’s Ataxia?
Friedreich’s ataxia is a rare genetic disease that causes difficulty walking, a loss of sensation in the arms and legs, and impaired speech. It’s also known as spinocerebellar degeneration. The disease causes damage to parts of your brain and spinal cord and can also affect your heart.
“Ataxia” means lack of order. There are a number of types of ataxia with a number of causes. Friedreich’s ataxia is one type of this condition.
Friedreich’s ataxia affects approximately 1 in every 40,000 people.
Although there’s no cure for Friedreich’s ataxia, there are several treatments available to help you cope with the symptoms.
Friedreich’s ataxia can be diagnosed between ages 2 to the early 50s, but it’s most commonly diagnosed between ages 10 to 15. Difficulty with walking is the most common initial symptom of the condition. Other symptoms include:
- vision changes
- loss of hearing
- weak muscles
- lack of reflexes in your legs
- poor coordination or lack of coordination
- speech problems
- involuntary eye movements
- foot deformities, such as clubfoot
- difficulty sensing vibrations in your legs and feet
Many people with this condition also have some form of heart disease. Approximately 75 percent of people with Friedreich’s ataxia have heart abnormalities. The most common type is hypertrophic cardiomyopathy, a thickening of the heart muscle. The symptoms of heart disease include heart palpitations, chest pain, and shortness of breath. Friedreich’s ataxia can eventually lead to diabetes.
Friedreich’s ataxia is a genetic defect that’s inherited from both parents by what’s called “autosomal recessive transmission.” The disease is linked to a gene called FXN. Normally this gene will cause your body to produce up to 33 copies of a specific DNA sequence. In people with Friedreich’s ataxia, this sequence may repeat 66 to over 1,000 times, according to U.S. National Library of Medicine’s Genetics Home Reference. When production of this DNA sequence spirals out of control, severe damage to the brain’s cerebellum and the spinal cord can result.
People with a family history of Friedreich’s ataxia are at greater risk of inheriting this disease. If the defective gene is only passed down from one parent, the person becomes a carrier of the disease but usually doesn’t experience symptoms of it.
Your doctor will look at your medical history and perform a complete physical exam. This will include a detailed neuromuscular exam. The exam will focus on checking for problems with your nervous system. The signs of damage include poor balance, lack of reflexes, and lack of sensation in your joints.
Your doctor may also order a CT scan and MRI of your brain and spinal cord. An MRI shows images of your body’s inner structures. A CT scan produces pictures of your bones, organs, and blood vessels. You might also have regular X-rays of your head, spine, and chest taken.
Genetic testing can show if you have the defective frataxin gene that causes Friedreich’s ataxia. Your doctor might also order electromyography to measure the electrical activity in your muscle cells. A nerve conduction study may be done to see how quickly your nerves send impulses.
Your doctor might want you to have an eye exam to check your optic nerve for signs of damage. In addition, your doctor may do echocardiograms and electrocardiograms to diagnose heart disease.
Friedreich’s ataxia can’t be cured. Your doctor will treat underlying conditions and symptoms instead. Physical therapy and speech therapy can help you function. You may also require walking aids to help you move around. Braces and other orthopedic devices or surgery might be necessary if you develop a curved spine or problems with your feet. Medications may be used to treat heart disease and diabetes.
Over time, Friedreich’s ataxia becomes worse. About 15 to 20 years after symptoms emerge, many people with Friedreich’s ataxia have to rely on a wheelchair. Those who have advanced ataxia might not be able to get around at all. Heart disease is the leading cause of death among people with Friedreich’s ataxia. It usually becomes fatal by early adulthood. People with mild ataxia symptoms generally live longer.
Friedreich’s ataxia leads to diabetes in about 10 percent of people who have it. Other complications include heart failure, scoliosis, and difficulty digesting carbohydrates.
There’s no way to prevent Friedreich’s ataxia. Since the condition is inherited, genetic counseling and screening are recommended if you have the disease and plan on having children. A counselor can give you an estimate of your child’s chances of having this disease or carrying the gene without showing symptoms.