Scientists have ruled that tragic NFL star Shane Dronett, who shot himself dead in the kitchen of his home, had been suffering with a brain disease brought on by years of concussions.

Boston University School of Medicine has confirmed that tests show Mr Dronett had chronic traumatic encephalopathy (CTE) associated with repeated head traumas.
Mr Dronett killed himself at the age of 38, three years after retiring from the NFL in 2006.

He was survived by a wife and two daughters who witnesses daily his transformation from a loving, affable family man to a paranoid, and sometimes scary, individual.
His playing career spanned 20 years, including 10 seasons in the NFL, first with the Denver Broncos and then the Atlanta Falcons.
He played defence on the 1998 Falcons team that had a storybook Super Bowl run.
Chris Nowinski, co-director of the university's Centre for the Study of Traumatic Encephalopathy said: 'There is evidence of CTE in his brain making him yet another former NFL player who had definite CTE.'

Loving: Shane Dronett with his wife and daughters before the brain disease took hold of him and completely changed his personality
He added that the centre has studied brain tissue from 14 former NFL players and found evidence of CTE in 13 of them.

Usually found in much older dementia patients, CTE is an accumulation of an abnormal protein in the brain called tau, which do not heal.
For Mr Dronett's wife Chris, the findings have brought some degree of comfort.

She said: 'I had nowhere to turn. I didn't know anything about CTE. I didn't know other players were going through this type of stuff.

'I think if Shane knew at the time how serious playing through concussion could be down the road, he would have backed off.'

She recalled how she first noticed his decline in 2006 when he had a bad dream.

Mrs Dronett told CNN: 'He woke up in the middle of the night and started screaming and told everyone to run out of the house.

'He thought that someone was blowing up our house. It was very frightening.'

Two weeks later, there was another outburst, followed by many others.

His paranoia was gradually being matched by periods of confusion and rage that could be result in violence.

'He was ordering, and he got mad at an employee and just punched him in the face,' she said.
Mrs Dronett added: 'He thought the guy was shaking the ice weird or something, and he took him down in the restaurant.'

It was a far cry from the man the family had known - outgoing, jokey.

Mrs Dronett said he was 'someone who would light up the room.'

Hayley added: 'He was just the best dad in the world.'

Speaking about his career and the pounding he would take as a professional football player, Mrs Dronett said: 'Shane didn't come out of games because he always said NFL players are so expendable.

'And if you're not out there, the next guy will be.

'There were times when he'd be slow getting up and kind of try to shake it off and get back in there.

'He would have headaches and he would say "I wish someone would split my head open with an axe and relieve the pressure," but it wasn't even an option to come out of the game.'
In 2007, at the height of his weird behaviour, Mr Dronett was found to have a brain tumour.
Mrs Dronett said: ''I was almost relieved because I was thinking, "OK, here is the answer to why he's acting like this, because he had a tumour".

'And then after he recovered from the tumour being removed, he was back to the same symptoms of paranoia.'

Researchers at the university, however, call the brain tumour potentially confounding, but most probably not a reason behind his behaviour.

Dr. Robert Stern, co-director of the BU CSTE, said: 'There's no way we would ever know what was specifically caused by the tumour or the surgery for the tumor or CTE.

'But more than likely at least some of his behaviour and symptoms were associated with the worsening of the CTE.

'What we know is that by definition, a lineman will have their head hit almost every play of every game and every practice.

'The estimates are around 1,000 or more hits for a lineman every season.

'I think the issue is that the brain was not meant to be hit even sub-concussively 1,000 times a year.

The NFL has since looked into taking steps to limit contact to the head and to ensure that concussions are properly treated.
Mr Dronett's disturbing behaviour came to a head during a ski trip Mrs Dronett took with Hayley in January 2009.

She said: 'He called us 100 times a day, wondering where we were and we'd tell him we're in Utah ... and he just didn't believe it.
'He thought people were driving around the house and he was wondering who had been following him that day. It was just very scary.'

Mr Dronett was supposed to pick up his wife and daughter at the airport but didn't turn up.
The next morning, Mrs Dronett saw her husband standing in the hallway of their home, with a gun.

Referring to the moment he blasted himself to death, she said: 'I saw the gun, and I ran out the front door.

'He had gone into the kitchen, and as soon as I put my hand on the front door, I heard it.
'He was always so full of life. Even his darkest moments, I just still never imagined that he would do that.

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