Michael J. Fox recalls the moment he was diagnosed with Parkinson’s

Michael J. Fox made his 41st and presumably final appearance on “Late Show With David Letterman” on Wednesday. And as with many of the final round of guests on the late night show, he didn’t have anything in particular to promote so much as to have a final chit-chat with Letterman, who retires in May.

Fox, who was diagnosed with Parkinson’s disease in 1991, spoke candidly about the moment when his doctor informed him he had the degenerative nervous system disorder.

“It was scary,” he said. “I was 29 years old and so it was the last thing I expected to hear. I thought I’d hurt my shoulder doing some stunt because I had a twitch in my pinkie. And the doctor said ‘You have Parkinson’s disease.’ He said, ‘The good news is that you have 10 years of work left.’”

But as Fox proudly announced, he’s managed to keep going for more than 20. He even had a new series, “The Michael J. Fox Show,” which aired for a season on NBC in 2013.

Fox, whose Michael J. Fox Foundation is working to discover more clear-cut biomarkers to diagnose people with the disease before they start to display symptoms, was amazed that the way it’s diagnosed is still akin to taking a drunk driving test.

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