After the latest suicide Dave Duerson, however, and on Monday's announcement that he also had chronic traumatic encephalopathy, a brain damage previously associated with boxers, shocked the finding none. Duerson became the 14th player retired N.F.L. — 15 audited by Boston University researchers — testing positive for the condition.
Water and Duerson bookend a remarkable SHIFT in the understanding of football brain trauma: four years after some positive tests begged explanation, questions mainly surrounds the absence of negative.
"Do you have to worry about which players — I can imagine that we all have it," said Chidi Ahanotu, 40, who played defensive lineman for Tampa Bay from 1993 to 2004. "To what extent, I do not know. But I do not know how you think.
So far, however, each successive cases of C.T.E. said more about the presence of the disease than the actual width.
Of 15 players who tested by B.U. researchers that this point is far from a random sample of N.F.L. pensioners who may constitute the broader population. Many of the players died in circumstances which may be related to C.T.E.: water and Duerson with suicide, John Grimsley from a gun accident, Tom McHale from an overdose. Their families donated since brains in large part to request an explanation for their behavior.
-This is a huge selection bias, so you can't make any conclusions about the existence or occurrence of the disease, says Dr. Ann McKee, Group B.U. lead neuropathologist and Director of neuropathology at the New England Veterans Administration medical centers.
She added: "a family is much more likely to donate a loved brain if they have even the smallest suspicion that something was wrong. If they were absolutely sure they were functioning 100 percent normal, they are much less likely to go through the process. "
In other words, although 93 percent of players tested so far have had C.T.E., it does not mean that 93% of retired players who live today, although if they do, not the disease jeopardizes their memory, emotional condition or impulse control in an appreciable manner.
The only test for the condition is the brain autopsy after death.
Together with a West Virginia University group that have found similarly high levels of the retired footballer C.T.E., what Boston University researchers require most today is not more middle-aged N.F.L. veterans who died with symptoms, but players of all ages – and nonplayers – who never showed symptoms.
B.U. has been brain-donation commitments from 128 live, current and retired N.F.L. players, but only 11 have died, and have brains that are pending an autopsy. McKee said that she has examined about 300 nonplaying males and never find C.T.E. — but not many of whom were middle-aged, impeding sound comparisons case water and Duerson.
"We desperately Need is what one would call a healthy brains," said Dr. Robert-Cantu, a Co-director B.U. group. "If they have C.T.E., then that opens up lots of other issues."
If the tests find asymptomatic players without the disease, would figure 93% fall drastically and provide a more fair assessment of the player's actual ability to have or develop it. If high-functional players brains shows still protein deposits and other pathologies that marks C.T.E., that would raise the question of why some people with the disease suffer from injuries and others not.
"People with mild illness can be flexible – resilient for various reasons, their genetic make-up, most likely, '' McKee said. "So they would be considered positive, but an asymptomatic cases.
"Secondly, if someone's brain disease, not just C.T.E. without say Alzheimer's disease, is this thing called cognitive reserve. Some individuals who are intelligent and have a great capacity for rewiring their nervous system, or take different paths to access the same information may have a lot of structural damage, but shows symptoms. "
The fact that 14 retired N.F.L. players were found to have C.T.E. can be spun in many directions, of course. To add the "out of 15 tested" stresses the existence of a problem. To say that it is "just" x "case" of a population of around 15,000, sceptics within and outside the N.F.L. once did with each successive cases only minimized what the presence of even the "x" positive means — that certain players that wound up with a devastating disease that simply does not exist, people who have suffered repeated brain trauma.
As recently as last year, Johns Hopkins University gave a N.F.L.-sponsored symposium pointedly entitled "traumatic brain injury in professional football: an evidence-based perspective," the leaflet cited "hype" and "claims" problems, and whose Director accused McKee misleading people.
-The only player that I know of which have been investigated are those that have died and ended up on Dr. McKee table, as a doctor, Constantine Lyketsos of Johns Hopkins, said in an interview before the Symposium. "We do not know the denominator here. It can be 12 or 15 or 15,000. "
It is neither, of course. Of brain diseases among retired N.F.L. players may wind up stunningly high – especially among linemen – but that 93% figure will at last be diluted by slower healthy brains. Then again, is to suggest that the only 14 players with C.T.E. have been found and that the other 14,986 men will be affected is absurd.
In other words: if 14 out of 15 people who died in a town of 15,000 in later received diagnoses varying degrees of water poisoning, the rest would have legitimate reason to worry. And in order to avoid water fountains.
No comments:
Post a Comment