(FOX 11) - A new study finds that nearly every deceased former NFL player who donated their brain for research suffered from a crippling brain disease.
Researchers studied autopsy results from 111 NFL players' brains donated to science after their death.
Of those 110, 90 percent were found to suffer from Chronic Traumatic Encephalopathy or CTE.
It is caused by repeated blows to the head or repetitive brain trauma.
Although the disease can be diagnosed only after death doctors say many of the symptoms like impaired judgment, aggression, depression and sometimes suicidal behavior are treatable and preventable.
FOX 11 stopped by UCLA to speak with Dr. Christopher Giza, director of the UCLA Steve Tisch BrainSPORT Program
"If you don't read beyond the headline, you miss a lot of the substance of the scientific paper," Giza said. "We know this condition exists, I think the next really two most important questions that we can't answer with case reports are why does it happen, although we suspect head trauma has a role in it it's not the only factor, and the other is what's the risk of people getting it?".
Giza said with CTE, answers are difficult to come by because it can only be diagnosed on someone who is deceased.
"CTE is a pathological diagnosis, so it's an accumulation of a protein that accumulates in the brain tissue and it's either part of the degenerative process or it's a marker that degeneration has occurred," Giza said.
Giza told FOX 11 that the study is great for bringing awareness to CTE, but no firm conclusions about CTE risk can be drawn from the study, especially for younger athletes.
Dr. Giza added that researchers clearly drew some conclusions from the findings, but this kind of study doesn't make possible firm conclusions about risk for CTE, which is one of the next big questions for scientists.
"The sports participation pyramid is like this, there's a few thousand elite athletes at the top of the pyramid, but it's built on a base of millions of youth athletes, and the young brain is different than the elite brain," Giza said.
The study's main author also admits it was biased in that it only was based off of brains donated from deceased players who had already been previously showing CTE symptoms
For more on the study click here.
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