An 83-year-old woman says she feels trapped in her care home after discovering the majority of residents are suffering from dementia.

The woman, who does not want to be named, admits she was too trusting of claims made by representatives of Fosse House, near Waitrose on Ermine Close, where she was encouraged to move recently.

But since shifting to the home in June, the woman has been upset after seeing some residents in an agitated state, including a man “going berserk” in the dining room.

She said: “Last Christmas, I felt very, very lonely. So I decided to sell my flat in Broxbourne, move out before winter and settle in somewhere before this Christmas as I don’t want to be on my own anymore.”

The octogenarian approached Quantam Care, a not-for-profit company which provides services and runs homes for thousands of older people, telling them she wanted somewhere where the majority of residents were mentally agile, and they recommended Fosse House.

She added: “That is the crux of my complaint. I don’t have dementia. There are 81 rooms here, and many people appear to have some form of the condition.”

The woman, who is paying £110 a day, explained: “If you haven’t got dementia, it is very stressful. I have been to the doctor as it has made me feel sick because of the anxiety. I’m worried I’m going to have a stroke.

“No one has been attacked in front of me, because staff come to the rescue, but they have a hell of a job quietening them down, and I don’t know when they are going to flare up.”

The woman added: “I really cannot stand much more of this. At 83 years of age I want peace and happiness for the rest of my life.

“It’s like being in prison – I have to keep my door locked all the time as someone tried to get into my room.”

The woman says she was not made aware of how many residents suffered dementia, but admits she did not research this aspect of the home before moving in. She is now keen to find alternative accommodation as soon as possible.

A spokeswoman for Quantam Care said that of the 81 residents at Fosse House, over 30 do not have a diagnosis of dementia, and all prospective residents go through a lengthy and comprehensive process before making the decision to move into their homes.

The spokeswoman said meetings have been held with the woman to resolve any concerns and help her find alternative accommodation.