When Tony Christie arrived at his specialist last week there was a disorientated and agitated lady on the steps outside who did not know where she was.
The man with her – her son, Tony presumes – had to reassure her that they had just seen her doctor and were waiting for a car home.
"It threw me for a moment," the singer admits, quietly.
For a relentlessly positive person, this admission perhaps reveals a little of the fear Tony has felt since he was first diagnosed with dementia.
That lady was a glance into the future; a glimmer of what his own might hold.
Tony Christie discusses dementia diagnosis after sharing fears over his memoryTwo weeks ago, the 79-year-old famed for early 70s' hits Las Vegas, I Did What I Did for Maria, and (Is This the Way to) Amarillo – an even bigger hit with comedian Peter Kay and Comic Relief when it was re-released in 2005 – revealed he was living with the condition.
Today, he has agreed to talk in detail about it for the first time.
But it is clearly difficult for this slim, energetic man with his perfectly white, youthful smile and snappy style, to consider its effects on him.
He doesn't like to "dwell" on the condition and to that end he is about to travel to Nashville to record new music, and start touring the UK in the spring. He says: "I'm used to working, it's daunting when I don't work, and I love the music – and that is good for what I have got, it's medication.
"Whatever this is, it is, and we will deal with it. I was a little bit down but I thought, 'I can still work, it’s not affecting my singing, my voice, my show.'
"As long as I can get on that stage and do what I was born to do."
I gently ask about the time which may one day arrive when he can no longer perform, when, possibly, he can no longer remember Sue, his beloved wife of 55 years, their three children and seven grandchildren.
He pauses. "That's the only worry," he says. But adds quickly: "I trust Sue."
Regularly picking up his trailing sentences, Sue, 74, always by his side, adds: "He will never lose that. We won't let him lose that. I can't imagine it and I don’t think about it. I just think we will be together forever, and we will, whatever happens."
Tony says, smiling: "That's one of the things that keeps me going and stops me worrying." What's more, he knows if he does forget all his lyrics there is one song he’ll always get some help with.
Tony Christie's first dementia symptoms as he says 'Worry and you're finished'He says, grinning broadly: "I don’t have to sing Amarillo, the crowd sings it anyway!"
Tony, born in Conisborough, South Yorks, has lived in Lichfield, Staffs, since returning to the UK from the home he and Sue had created in Spain when Kay released Amarillo.
He explains the first sign of his dementia was noticing his usually sharp recall had gone. "I would be the one people would ask 'who did this, who recorded that' – I knew everything. Now it's …" he shrugs, gently.
"I was suddenly thinking: 'I used to know this, I used to know that' Sue had to remind me of the name of someone I had known for 60-odd years. And my hobby was doing cryptic crosswords, I did them for 50 years. Now I can’t answer them all."
Two years ago, he and Sue went to the doctor, and within a few weeks tests revealed a small build up of "plaque" on Tony’s brain.
But there has been no great outpouring of emotion. As they sit beside each other, dressed smartly in matching black and white (Sue "does frocks", always has), they thank their faith.
Tony says: "I always ask the angels to help me, it gets me through. Every time before I go on stage I spend 10 minutes on my own speaking to the angels, 'thank you for everything, please help me through this show'. And it works. All I ask is let me do what I am here to do, let me go on stage."
The initial medicine doctors prescribed to slow the dementia’s development made Tony fatigued.
But the second medication has worked brilliantly, improving his condition. The couple are also hopeful for new drugs.
Tony's one concession to the disease is to have lyrics on an autocue, but he says he doesn't regularly need them. He urges anyone with symptoms to get checked.
He says: "I'm glad it all came out. If it helps other people with the same problem and makes them go and get on some tablets that will help, that's what we hope will happen." Sue thinks Tony's stoicism probably comes from his Yorkshire roots.
His grandad and uncles, who were miners, lived with them. His dad, a coal board accountant, came from a family of musicians, originally from Ireland, who were in a ceilidh band.
Tony recalls: "Dad stood me on a chair and I used to sing at five or six years old." And his long-term memory is still clear. He started work in the accounts office of a Yorkshire steel company but left to pursue his music and played working men’s clubs.
He joined bands in the late 60s, including Tony Christie And The Trackers – who cut a track with Billy Preston as session keyboard player, and a 17-year-old Jimmy Page "full of cold" on guitar, who would co-found Led Zeppelin.
Tony, managed by Harvey Lisberg, had three hits and a slot on pal Des O'Connor 's TV show.
Las Vegas came his way when Tom Jones ' manager turned it down – much to Tom's horror.
Fame persisted in Europe, Australia and New Zealand but not in the UK.
But Tony never had an ego. He loved his family and performed happily whenever or wherever he could.
And he has fond memories of some of music’s biggest stars, even if they did not treat him well.
Beatle John Lennon once rudely asked him to move his car from outside an LA studio. "It was hilarious. He wasn’t polite," giggles Tony. The Who's drummer, the late Keith Moon, borrowed £20 from him in a Park Lane club. He never got it back.
Tony says: "He comes over and says 'they won't let me have a tab'. He didn't know who I was."
Tony does not mind. Nor is he concerned that Amarillo, successful in Germany and Spain and would sell over a million copies by August 1972, only hit 18 in the UK chart in 1971.
It topped the charts for seven weeks in 2005 on its re-release in aid of Comic Relief. The accompanying video featuring the likes of comedians Peter Kay, Ronnie Corbett and Coronation Street stars William Roache and Anne Kirkbride.
The late Queen once confided to him the Royals often play it at family dos. He says: "I found myself walking through town the other day and all these schoolkids were walking behind me singing it. I joined in."
It is that matter-of-fact humour, and pure love of the job, that seems to be seeing Tony through.
He plans to do a gig on his 80th birthday in April. The show must, and will, go on.
Dementia UK is a specialist nursing charity and offers support to anyone affected by dementia, offering a free helpline and clinics with specialist Admiral Nurses. Tony supports their ‘I live with dementia’ campaign. Visit dementiauk.org