5 things to know about ALS and how Stephen Hawking survived it for decades

A diagnosis of Lou Gehrig's disease, or amyotrophic lateral sclerosis (ALS), is usually a death sentence, and it's one filled with pain and suffering, sometimes for years, before the victim finally succumbs to the disease.

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So how was world-renowned physicist Stephen Hawking able to survive the degenerative neurological illness and live for decades? Hawking was 21 when he was diagnosed with ALS and given only a few years to live, but he survived more than 50 years. He was confined to a wheelchair in near-total paralysis, breathed through a tube, used an electronic voice synthesizer to speak and could only move his little finger on one hand, but he lived until the age of 76 and made quite a name for himself during his lifetime, beating almost all the odds for those with ALS.

NEW YORK, NEW YORK - APRIL 12:  Professor Stephen Hawking onstage during the New Space Exploration Initiative "Breakthrough Starshot" Announcement at One World Observatory on April 12, 2016 in New York City.  (Photo by Jemal Countess/Getty Images)

Credit: Jemal Countess

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Credit: Jemal Countess

Hawking often credited his sense of humor as one of factors for his longevity, although doctors have said he was a rare ALS victim with a slow-moving form of the disease.

In a 2016 question and answer session, he said “his work” and “a sense of humor” kept him alive, according to The Washington Post.

Here are 5 things to know about ALS:

  • Amyotrophic lateral sclerosis is a progressive neurological disease that destroys the nerve cells and causes disability, according to the Mayo Clinic. Doctors don't know why victims develop the disease, although some cases are inherited. There is no cure for ALS.
  • The first symptoms of the disease include muscle twitching, weakness in the arms or legs or slurred speech. ALS is eventually fatal.
  • In the summer of 2014, millions of people started talking about ALS, according to the ALS Association, and raising money and awareness through the Ice Bucket Challenge. The challenge raised millions of dollars for ALS research.
  • Just over 6,000 people in the United States are diagnosed with ALS every year and just 10 percent will survive 10 or more years. The ALS Association says some 20,000 Americans have the disease at any given time. More men than women develop the disease, which usually strikes between the ages of 40 and 70, with an average age of 55.