Sept. 18, 2015 -- The latest data from a brain bank that focuses on traumatic head injury shows that 87 of 91 former NFL players tested positive for a brain disease associated with repetitive head injuries.
The degenerative disease, known as chronic traumatic encephalopathy (CTE), was identified in 96 percent of NFL players and in 79 percent of all football players studied, researchers from the U.S. Department of Veterans Affairs and Boston University told Frontline in an exclusive report Friday.
CTE can cause memory loss, depression and dementia. In total, brain tissue from 165 people who played football in high school, college, semi-pro leagues or in the NFL was examined after their deaths, according to Frontline.
Offensive and defensive linemen bore the brunt of the disease, with 40 percent of players at those positions suffering from CTE, according to the brain bank.
Past research has shown that constant minor head traumas may pose the greatest neurological danger, rather than the less common violent collisions that cause concussions, Frontline reported.
But since CTE can only be diagnosed posthumously, many of the players who have donated their brains for testing suspected that they had the disease while still alive, so researchers were working with a skewed sample, Frontline reported.
The NFL said in a statement to Frontline, "We are dedicated to making football safer and continue to take steps to protect players, including rule changes, advanced sideline technology and expanded medical resources. We continue to make significant investments in independent research through our gifts to Boston University, the [National Institutes of Health] and other efforts to accelerate the science and understanding of these issues."
In April, the NFL agreed to a $1 billion concussion settlement with former professional players, but appeals filed in August by some former NFL players who oppose the terms of the settlement will likely delay payments to thousands of other retired players until next year.