Football players more likely to develop neurodegenerative disease, study finds
By Nadia Kounang, CNN
updated 4:38 PM EDT, Wed September 5, 2012
(CNN) -- Just hours before the 2012 NFL season kicks off, a new study suggests that professional football players are three times more likely to have neurodegenerative diseases than the general population.
When researchers specifically looked at Alzheimer's disease and ALS -- amyotrophic lateral sclerosis, also known as Lou Gehrig's disease -- that risk increased to four times greater than the rest of us.
The study, published Wednesday in the medical journal Neurology, surveyed nearly 3,500 retired NFL players who were in the ...view middle of the document...
More than 2,000 former professional football players are currently suing the NFL, claiming that the league "downplayed and misrepresented the issues and misled players concerning the risks associated with concussions."
The NFL has repeatedly stated that player safety is a priority and that "any allegation that the NFL intentionally sought to mislead players has no merit."
Ohio State linebacker choosing career over concussions
While the study published Wednesday did not examine players' concussion history of the players, researchers did investigate whether the position played made a difference.
The study authors found that players in speed positions like quarterbacks and running backs were three times more likely to develop neurodegenerative disease than players in non-speed or lineman positions.
"If you had a quarterback running at a wide receiver, there's a lot of velocity," Lehman said.
However, "We have to be very careful and note that we don't know if this is a result of concussions," says Jeffrey Kutcher, associate professor of neurology at the University of Michigan.
"Are these increased risks because of exposure to contact? In their words, there's an assumption that there is causality there. I think a general lifestyle of playing sport at a competitive level is abusive. It's hard to do physically and mentally."
In addition, genetics and family history may also be factors for dementia and Alzheimer's but weren't accounted for in the study.
Studies have linked repeated concussions in football players to chronic traumatic encephelopathy, a neurodegenerative disease with Alzheimer's-like symptoms. Those symptoms can include depression, memory loss and mood swings. Former Chicago Bears safety David Duerson, who committed suicide, was diagnosed with CTE postmortem. It can be diagnosed only after death.
Player's text: Send my brain to NFL research bank
Research on CTE shows commonalities with ALS and Alzheimer's, and examining the neurodegenerative diseases might be the best way to look at it, Lehman said.
"CTE maybe one of the outcomes or causes, but we just can't tell."
Dr. Julian Bailes, a neurosurgeon who also chairs the Pop Warner Medical Advisory Board, said, "A study like this is very limited in its scope and how deep they can dig down. It's merely an observation in reporting in cause and death, and you can only draw so much -- but it supports in general a trend that we've seen, that neurodegenerative disease impacts...