Kinnear’s wife Bonnie has confirmed that her husband – who had controversial spells at St James’s Park as manager and director of football – was diagnosed with early onset vascular dementia in 2015.
The 74-year-old’s condition has since deteriorated, and she told the Daily Telegraph, she said: “He started to get moody – a bit depressed. I thought ‘this isn’t right’.
“Then he got aggressive in certain situations. It just wasn’t Joe. It was a problem trying to get him to see somebody, but we eventually got him to a doctor, and he was diagnosed in 2015.
“They classed it as early onset vascular dementia, and, since then, he has just deteriorated. He’s in the late stage. It’s heartbreaking to see how someone can change.
“He was larger than life. He loved people. He’d walk in a pub, buy everyone a drink, tell funny stories – and be the life and soul of the party.”
Kinnear was appointed as Newcastle manager in September 2008 following the shock resignation of Kevin Keegan. Kinnear had heart bypass surgery later that season, and but he returned to the club as director of football in the summer of 2013.
The former Tottenham Hotspur and Republic of Ireland defender resigned his position in February 2014.
Kinnear – who also had managerial spells at Wimbledon, Luton Town and Nottingham Forest – was first diagnosed with dementia the following year.