What is ALS? Early symptoms Canadians should know about after death of 'Star Trek' actor Kenneth Mitchell

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Canadian actor Kenneth Mitchell, known for his roles in "Star Trek: Discovery," "Captain Marvel" and "Jericho," has passed away from ALS at age 49. The Toronto-born film and television star was diagnosed with Amyotrophic Lateral Sclerosis (ALS) in 2018.

In an Instagram post on Saturday, Mitchell's family shared an obituary, with a photo of the actor with his two children, Lilah and Kallum.

"For five and a half years, Ken faced a series of awful challenges from ALS. And in truest Ken fashion, he managed to rise above each one with grace and commitment, to living a full and joyous life in each moment," the statement read.

The family described Mitchell as a "hope seeker," and "infectious laugher," a "Leafs supporter," a "world traveler," and "more than anything else, a proud father." They added his best traits showed in his parenting. "Regardless of his later disabilities, Ken discovered a higher calling to be more fully himself for his kids. Ken will be forever proud of who his children have become."

Mitchell began using a wheelchair a year after his diagnosis, and continued to work as an actor. In one of his "Star Trek: Discovery" roles, he portrayed a scientist who uses a hovercraft wheelchair named Aurellio. He also played an FBI agent who uses a wheelchair in the Hulu series "The Old Man."

Mitchell publicly shared his diagnosis in a 2020 interview with People.

"I think it, over time, became the theme of us accepting this with grace," Mitchell said. "Trying to see the beauty in it, in a way. I'll never forget, one of my Star Trek costars told me, because they had dealt with some trying times with illnesses and stuff, and I remember them communicating to me, saying, 'You have a choice. You can look at this in many different ways, but maybe try to look at this like a gift where you get to experience life in a way that most people don't.'"

Most people who are diagnosed with ALS die within five years of diagnosis. It's estimated about 4,000 Canadians are currently living with ALS, and approximately 1,000 Canadians die from it each year.

But what exactly is ALS and what does it do to the body? Here's everything you need to know.

What is ALS?

Amyotrophic lateral sclerosis (ALS) is a progressive terminal disease that affects "what are essentially the living wires that connect our brain to our muscles," explains Dr. David Taylor, vice-president of research at ALS Canada.

These "wires" are called motor neurons through which the brain signals the muscles. With ALS, the motor neurons degenerate and die, leading to a progressive paralysis.

"You lose the ability to move, speak, swallow and then what makes it terminal is eventually, the ability to breathe," Taylor tells Yahoo Canada.

Also known as Lou Gehrig's disease, or motor neuron disease, ALS is currently impacting about 200,000 people worldwide, approximately 4,000 of which are in Canada.

What causes ALS?

We still don't really know what causes ALS, according to the expert. For about 10 per cent of people who are diagnosed, ALS is passed down through genetics. "We can connect this to a specific genetic variant that can confer the disease in individuals.

"Otherwise, we don't know the exact cause — we're really honing in on that, and I think in the past several years, we've come a very long way. But it still continues to be something we're searching for," Taylor says.

Though genetics are the biggest known risk factor for ALS, Taylor adds that "to some extent" aging plays a part, as the disease is typically seen in middle-to-late stages of life.

It's also been linked to smoking and brain trauma, "but there's nothing that we have that's super definitive," he said.

What are the early symptoms of ALS?

Taylor explains ALS starts with a progressive weakness, either in the upper or lower body, as well as progressive slurring of speech or difficulty in speaking or swallowing.

Progressive weakness in the upper body can look like impaired handwriting, difficulty lifting or reaching, trouble with dressing or hygiene (for example, doing buttons, cutting fingernails, etc.) and other daily tasks.

In the lower body, it can include frequent tripping, difficulty on stairs, or getting out of a chair, as well as a foot dragging when walking or not being able to walk as far.

He notes people shouldn't be alarmed as many symptoms can overlap with other diseases. However, ALS Canada does have an online tool called ReferALS, with a checklist of early symptoms to encourage people to see an ALS specialist "as quickly as possible" if needed.

The current diagnostic delay in Canada is up to two years, which can be "most of an ALS patient's remaining life."

How is ASL treated?

There is no cure for ASL, but there are treatments that can improve the remaining quality of life or extend it. One treatment available is riluzole, an oral therapy in the form of a tablet.

"There are a couple other therapies that are more recently approved by Health Canada, we're still learning about what the effect of those are. But in clinical trials, they have shown that they can provide some slowing of the progression of the disease, but certainly not saving anyone," Taylor explains. "We're certainly looking to get better ones in the near future."

Taylor says it's an exciting time for research, saying "I think we're going to make some substantial strides." He encouraged Canadians to donate to ALS Canada for research and national advocacy, so "we can also ultimately fix this disease with the rest of the world."

For those who have a loved one who's been diagnosed, applying to register with a local ALS society can help get the right supports in moving forward.

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