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We have some news this morning about a brain disease known as CTE. It affects athletes in one of the biggest winter sports. NPR's Becky Sullivan reports.
BECKY SULLIVAN, BYLINE: The factors that cause CTE - or chronic traumatic encephalopathy - aren't unique to football, says researcher Dr. Jesse Mez.
JESSE MEZ: What we know from American football is that it's these accumulation of hits, thousands of hits over the career, that are really related to this disease and this pathology. We know less when it comes to hockey.
SULLIVAN: Mez is a neurologist at Boston University and co-author of the new study in the medical journal JAMA Network Open. The reason that he and his fellow researchers had studied football the most was because they rely on donations of brains from athletes who've died. For years, those mostly came from football. Now they finally had enough samples from ice hockey players - 77 brains, to be precise.
MEZ: So we had professionals, juniors, semi-professional, college, high school, youth.
SULLIVAN: Of those who only played youth or high school hockey, about 10% had CTE. But among professional players, that number was 96%. Selection bias is definitely a factor Mez acknowledges, because families may be more likely to donate brains if they saw signs of cognitive decline in their loved ones. Still, the relationship between CTE and the length of a player's career was clear.
MEZ: We found that with each additional year of play, the odds of having CTE increased by 34%.
SULLIVAN: The research gap between football and other sports had allowed questions about the risk to linger. Last year, in an interview on MORNING EDITION, NHL Commissioner Gary Bettman disputed that there could be a link between playing in the NHL and developing CTE.
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GARY BETTMAN: There have been isolated cases of players who have played the game, have had CTE, but it doesn't mean that it necessarily came from playing in the NHL.
SULLIVAN: Mez says he and his fellow researchers were able to look at 19 brains from NHL players. All but one showed signs of CTE. He says that should be concerning.
Becky Sullivan, NPR News.
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