Episodic Ataxia Has Intermittent Symptoms

Although episodic ataxia and Friedreich ataxia have some shared symptoms, they appear in different patterns. In Friedreich ataxia, symptoms occur all the time. They’re progressive (get worse with time), and new symptoms might appear as time goes on, but there aren’t any “breaks” between periods of symptoms.

In episodic ataxia, symptoms are periodic (that’s why it’s called episodic). People with episodic ataxia experience episodes of symptoms, while symptoms between episodes are usually mild or absent. Episodes can start with physical or emotional stress or other triggers.

Friedreich Ataxia Causes Heart Problems

One distinctive feature of Friedreich ataxia that isn’t seen in episodic ataxia is the development of heart complications. Friedreich ataxia can cause the heart muscle to thicken, which leads to issues like chest pain and arrhythmias.

As Friedreich ataxia causes your heart function to decline, more serious heart problems can occur. You might experience heart failure or cardiac arrest (heart attack). Heart problems are the most common cause of premature death in people with Friedreich ataxia.

Friedreich Ataxia Can Cause Diabetes

Roughly 30 percent of people with Friedreich ataxia develop diabetes, a complication that isn’t linked to episodic ataxia. Diabetes usually develops 10 to 15 years after the initial ataxia diagnosis. This happens when Friedreich ataxia damages the pancreas, the gland that produces insulin.

When you don’t produce enough insulin, glucose (blood sugar) builds up in your bloodstream and causes high blood sugar, insulin resistance, and eventually diabetes. Pancreas damage from Friedreich ataxia can also make insulin less able to do its job of transferring glucose into your cells from your blood.

Different Gene Mutations Play Roles

Episodic ataxia and Friedreich ataxia both have genetic causes, but they originate from different genes. Genetic ataxias are usually inherited from your parents due to specific genetic mutations they pass down.

Friedreich ataxia is linked to a mutation in a gene called the FXN gene, which is involved in the production of a protein called frataxin. Experts don’t fully understand what frataxin does, but they know it supports energy production inside your cells. With an FXN gene mutation, your cells produce less energy and are more prone to damage.

Episodic ataxia can involve different genes depending on the type of episodic ataxia you have. One of the most common types of episodic ataxia, called episodic ataxia type 2 (EA2), stems from changes to a gene called CACNA1A.

Friedreich Ataxia Can Cause Musculoskeletal Problems

Some people with Friedreich ataxia eventually develop problems with their bones and muscles. While episodic ataxia can involve muscle stiffness, certain musculoskeletal problems are only linked to Friedreich ataxia.

Many people with Friedreich ataxia develop foot problems, like very high arches or feet that turn inward. Coupled with balance and coordination problems, these foot problems can make standing and walking difficult.

Scoliosis, or unusual curvature of the spine, also commonly develops in people with Friedreich ataxia. You might need a back brace or even surgery to treat scoliosis associated with Friedreich ataxia.

Episodic Ataxia Has Many Types

Friedreich ataxia is caused by the same gene variant and has similar symptoms. Episodic ataxia has more variations because there are eight known types.

The most common types of episodic ataxia are episodic ataxia type 1 (EA1) and EA2. Experts have identified the gene changes linked to these two types. Some rare types are better understood than others — the rarest types have only been identified in one or two families.

Friedreich Ataxia Has a Shorter Life Expectancy

Many people with episodic ataxia live long and active lives, and some even stop getting episodes of ataxia symptoms. Episodic ataxia generally doesn’t impact life expectancy.

Friedreich ataxia can have a shorter life expectancy because of heart problems and other complications. It’s also a degenerative condition, which means it gradually worsens with time. Still, Friedreich ataxia can have different outcomes for different people, with some living well into their 60s or beyond.