Former NFL player Phillip Adams, who shot and killed 6 people before taking his own life in April, had severe brain damage from CTE, researchers from Boston University said in a statement Tuesday.
"His 20-year career put him at high risk for development of CTE," Dr. Ann McKee, a neuropathologist and expert on neurodegenerative diseases at Boston University who conducted the study on Adams' brain, said during a press conference attended by insider.
"It's a progressive disease that worsens with age. In many instances, it is a disease of the young," she added.
McKee said Adams had severe CTE in both frontal lobes of his brain, adding that damage to the frontal lobe is associated with violent activity.
"We are pleased to have a better understanding of the mental turmoil that Phillip was dealing with during the last moments of his life," Adams parents said in a statement shared with Insider.
According to his parents, Adams was "desperately seeking help from the NFL," but they said all of his claims were denied because of his "inability to remember things and to handle seemingly simple tasks such as traveling hours away to see doctors and going through extensive evaluations," according to the statement. Insider has reached out to the NFL for comment but has not received a response at the time of publication.
Adams suffered from stage-II CTE, which is the second-most severe type of the disease only to stage-III. The only known NFL player to suffer from stage-III CTE was former New England Patriots tight end Aaron Hernandez, who was convicted for the murder of Odin Lloyd in 2013.
Hernandez was later found dead in his jail cell and his death was ruled suicide. The autopsy on Hernandez's brain revealed that the former tight end suffered from "the worst case of CTE ever found."
McKee said that Adams' autopsy revealed that his CTE levels were similar to that of Hernandez.
"Mr. Adams' CTE pathology was different however from other young NFL players with CTE. It was different in that it was unusually severe in both frontal lobes. In its frontal lobe predominance, Adams' CTE pathology was similar to that of another young NFL player, namely Aaron Hernandez," McKee said during the press conference.