On Sun, 17 Nov 2013 08:30:57 -0500, "Mike Marlow"
That's the point of the article - there is no evidence that it often does.
Take a second look at the article.

That's just one article. There's many articles and examples to the
contrary. Consider Muhammid Ali. He's been diagnosed with Parkinson's
syndrome, a condition which is often associated with boxers.