Dame Barbara Windsor has been diagnosed with Alzheimer's disease.

The 80-year-old actress' husband Scott Mitchell has confirmed his wife is taking medication to help manage the ''cruel disease'' - which is the most common cause of dementia and can cause memory loss - and revealed she broke down in tears when she was given the awful news.

He told The Sun newspaper: ''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.

''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.' ''

The 'Carry On' star has been in a ''definite continual confusion'' since she turned 80 last August, and while she enjoys going out for walks, Scott - who has been married to the actress for 18 years - admitted she feels ''a kind of shame'' about the diagnosis.

He said: ''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.

''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.''

Scott first noticed a difference in Barbara in 2009 when she found it ''difficult'' to learn her lines, and by 2012 he encouraged her to go to the doctor for tests after noticing a ''slight sadness'' develop in her.

He said: ''From the start, I said to Bar, 'I want you to have these tests because you're getting a bit forgetful and we may as well just nip it in the bud'. She was fine about it.

''In my mind, I truly hoped it would be nothing. Just a bit of old age, you know?

''But if I'm honest, I had also noticed a slight change in Barbara's personality. Rather than being her normal positive, bubbly self, it felt like a thin veil had been drawn across her that was more serious.

''At times, I'd see a slight sadness develop that just wasn't her. I put it down to age, but I now believe it was the very start of this illness.''

Barbara has now retired from charity work as well as acting as a result of the disease.

Scott said: ''The confusion has started to set in much more over the past few weeks, so we have decided she should now retire from charity work as well as acting.''