Barbara, 80, has been taking medication to help manage the degenerative brain disease, but in recent weeks her symptoms of memory loss and confusion have grown steadily worse.
Now her devoted husband Scott Mitchell has decided to go public with the news in an exclusive, unpaid interview with The Sun.
He says: “Firstly, I hope speaking out will help other families dealing with loved ones who have this cruel disease. Secondly, I want the public to know because they are naturally very drawn to Barbara and she loves talking to them.
“So rather than me living in fear she might get confused or upset, they’ll know that if her behaviour seems strange, it’s due to Alzheimer’s and accept it for what it is.”
Sitting with her husband Scott in the neurologist’s office, Dame Barbara — famed for her endearing giggle — started to cry.
After undergoing several hours of mental agility tests, followed by a brain scan and lumbar puncture, the couple had just been given the heartbreaking news that has turned their life upside down.
Barbara, star of stage and screen since she was just 12 years old, has Alzheimer’s — the degenerative disease that slowly damages the brain, causing dementia and memory loss.
Sitting in front of me now, Scott, 55, bites his lip, clearly struggling to talk publicly about the devastating diagnosis they were given on April 22, 2014, and have kept under wraps until now.
“When the doctor told us, she began crying then held it back, stretched her hand out to me and mouthed, ‘I’m so sorry . . .’
“I squeezed her hand back and said, ‘Don’t worry, we’ll be OK’.”
He stops talking as tears spill silently down his face — the pressure of dealing with such a cruel illness all too palpable.
“I can’t protect her any longer. I’m doing this interview — and I would like to make clear that I’m not being paid for it and it’s the only one I’ll be doing — because I know that rumours are circulating in showbusiness circles.
“And, since her 80th birthday last August, a definite continual confusion has set in, so it’s becoming a lot more difficult for us to hide.
“I don’t want it to come across that she’s sitting there unable to communicate, because she’s not.
“We’re still going out for walks or dinner with friends and we still laugh together a lot. She loves going out and it’s good for her — she comes alive. And of course, the public are naturally very drawn to her, which I don’t want to stop.
“But as soon as we leave the house, I live in constant terror that she’s going to say something, or suddenly have a panic attack, or get photographed when she’s not looking right.
“I didn’t want someone else to dictate how or when the diagnosis came out, so that’s why I’m speaking about it now.
“I’m doing this because I want us to be able to go out and, if something isn’t quite right, it will be OK because people will now know that she has Alzheimer’s and will accept it for what it is.”
Barbara — or ‘Bar’ as Scott often calls her — knows he is giving this interview. But does she fully understand the implications of it?
“She often asks me, ‘Do the public know that I’m not well?’ And she asked me again this morning.
“I said they didn’t yet, but we were going to have to let them know because so many people are talking now. But if she forgets that she gave me her blessing, well, I’ll just have to deal with that,” he says matter-of-factly.
“Unfortunately, I notice she feels a kind of shame about it. There’s a vulnerability there and I keep telling her, ‘Bar, no one will think you’re silly for having this’.
“I explain that if someone has cancer, no one looks at them and thinks ‘How ridiculous’. We sympathise and it’s the same with this.”
Shortly after the diagnosis, Scott confided in a small circle of trusted friends — myself among them — who socialise regularly with the couple and had started to notice her occasional repetitiveness and confusion.
But he protected her from the news going public because at first Barbara, with whom he recently celebrated 18 years of marriage, struggled to accept the diagnosis. “We walked out of the neurologist’s office and it was almost as if she chose to forget what we had just been told.