Former NFL player Phillip Adams, who shot to death six people and killed himself, suffered from CTE – USA TODAY

Phillip Adams, the former NFL player who in April shot to death six people and killed himself, suffered from the debilitating brain disease chronic traumatic encephalopathy (CTE), the doctor who conducted the brain study announced Tuesday. 

Ann McKee, a neuropathologist who as director of Boston University CTE Center led the examination of Adams’ brain, presented the findings during a news conference that included Sabrina Gast, the coroner of York County, South Carolina, where the killings occurred April 7

McKee said Adams suffered from “severe” frontal lobe damage similar to what was found in Aaron Hernandez, the former NFL tight end who was convicted of murder in 2015 before killing himself in 2017.

CTE, the neurodegenerative disease linked to concussions and repetitive head trauma from football and other contact sports, has been associated with behavioral and mood changes, according to the Mayo Clinic and multiple studies.

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Of the possible link between violence and CTE, McKee said, “So we have seen this behavior. We have even see homicidal behavior in other individuals diagnosed with CTE. It’s difficult to say that it alone resulted in these behaviors because usually it’s a complicated issue with many other factors.

“But certainly we have seen this behavior and it is in fact not what I would consider unusual in this disease.”

Adams had stage 2 CTE, with stage 4 being the most severe, according to McKee.

In the Adams’ shootings, those killed included a prominent local doctor, his wife and their two young grandchildren. Two men working at the doctor’s home also were killed.

Toxicology analysis of Adams showed amphetamines, for which he had a prescription, according to the coroner. That included Kratum, a drug that can be purchased over the counter and in low doses works as a stimulant and in higher doses can have an opiate effect, according to the coroner, who said there is no FDA-approved use for the drug.

The coroner said she did not know how the drugs might have affected Adams’ behavior.

Adams, a cornerback who played college football at South Carolina State, was a seventh-round pick of the San Francisco 49ers in the 2010 NFL draft. Between 2010 and 2015, he played for six teams – the 49ers, New England Patriots, Seattle Seahawks, Oakland Raiders, New York Jets and Atlanta Falcons – and was 32 at the time of the killings.

He died from a self-inflicted gunshot wound and his family members donated his brain to the Boston University CTE Center. CTE can be diagnosed only after death with brain tissue analysis.

Adams’ sister, Lauren, told USA TODAY Sports that Phillips Adams’ behavior “shifted dramatically’’ over the past couple of years. 

“His mental health degraded fast and terribly bad,” Lauren Adams told USA TODAY Sports the day after the shootings. “There was unusual behavior. I’m not going to get into all that (symptoms). We definitely did notice signs of mental illness that was extremely concerning, that was not like we had ever seen. … 

“He wasn’t a monster. He was struggling with his mental health.” 

Adams was “desperately” seeking help from the NFL, according to a statement from his family that was read during the press conference.

“After going through records from his football career, we do know that he was desperately seeking help from the NFL but was denied all claims due to 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 family’s statement read by Lisa McHale of Concussion Legacy Foundation that supports those affected by CTE. “We now know that his deficits were most likely caused by the disease.”

The NFL did not immediately respond to a request for comment.

The coroner said Adams’ family told her that the former NFL player complained of excruciating pain from his injuries, often had memory issues and difficult sleeping.

Adams’ case has fueled ongoing talk about the apparent link between CTE and violence. 

The suicide of Junior Seau, who was suffering from CTE when he killed himself in 2012 with a self-inflicted gunshot wound, drew national attention to issue. Hernandez, the former NFL player who was convicted of murder in 2015 before killing himself in 2017, was found to have severe CTE. 

In 2017, the Boston University CTE Center reported that 110 of the 111 players they’d examined showed they suffered from CTE.  On Tuesday, McKee said the Boston University CTE Center diagnosed it in 700 individuals, including over 315 former NFL players. 

McKee said “the holy grail of our research” would be to find a way to detect CTE in living people because it would provide the ability to monitor how the disease is responding to specific therapies. 

During a search of Adams’ bedroom after the killings, law enforcement officers found numerous notebooks with “cryptic writing with different designs and emblems,” according to a copy of a search warrant provided by the York County Sheriff’s Office 

“Detectives were unclear if this was a potential motive or if there was another motive involved,” according to the search warrant. 

On Tuesday, York County Sheriff Kevin Tolson said his investigators are waiting for FBI analysis of the notebooks. 

Lauren Adams told USA TODAY Sports she thinks her brother was seeing a therapist before he retired from football and subsequently saw other doctors for his mental health issues. 

As things got progressively worse, she said, her brother neglected his hygiene and withdrew from people. 

“He’s always been into looking nice,” she said. “Like he’s always been like a ladies man. He stopped dating. It was just a lot things that were part of his character that just disappeared. 

“So many people come up to me or call me or text me and ask me, ‘What’s going on with your brother?’ And I’m like, ‘I don’t know.’ ” 

Mood changes related to CTE, according to the Psychiatry Neuroimaging Laboratory, “often involve problems with depression, irritability, loss of motivation, or suicidal thinking or behavior. Behavioral changes are typically seen as problems with impulse control which can lead to aggressive or violent behaviors, or problems with substance abuse.” 

A 2020 literature review published in The Journal of the American Academy of Psychiatry and the Law concludes that “much stands in the way of using CTE as a defense for murder at this time.”

The biological validity and reliability of CTE is untested, according to the review, which also states, “There is no consensus as to whether CTE is a discrete illness and whether it is distinguishable from other forms of dementia and neurotrauma.”