Hundreds of older people in North Devon and Torridge may be living with undiagnosed dementia according to estimates by the NHS.

Figures collected by GPs show there are 1,710 across the two districts who have been diagnosed with some form of dementia, with 1,020 in North Devon and 690 in Torridge.

However, estimates by the NHS based on the age profile and gender of patients, suggest the real figure may be 2,873.

The figures are being collected in response to the Prime Minister’s Challenge on Dementia set up by the previous PM, David Cameron.

The Department of Health wants GP surgeries in England to increase the rate of diagnosis.

The latest data, for November, shows that the diagnosis rate for the whole of England is 68.2 per cent, but area to area this ranges from 25 per cent to 90 per cent.

North Devon and Torridge are both below the national figure, with a diagnoses rate of 61 per cent in North Devon and 57.5 per cent in Torridge.

Sally Copley, Alzheimer’s Society’s director of policy campaigns and partnerships, said: “The essential first step to the care and support everyone should have a right to is a diagnosis.

“Research has found that people with dementia who live alone, or in care homes, or from BAME communities, have lower rates of diagnosis – contributing to the variation we’re seeing across the country.

“People tell us that our support is a lifeline, but we cannot reach them if we do not know who they are.

“In areas with low diagnosis rates the Government has to work with the NHS to find out what’s going on. People with dementia deserve better.”

Dementia is a term used to describe symptoms such as loss of memory, behaviour changes and problems in reasoning.

The most common cause of dementia is Alzheimer’s disease, which accounts for around 60 per cent of cases, but it can be the result of brain damage caused by a stroke or neurological conditions such as Parkinson’s.

Dementia can affect people at any age and across England 465,000 people have been diagnosed.

But the vast majority of cases are in older people. After the age of 65 the likelihood of dementia rises. It peaks for men in their early 80s when a quarter suffer from dementia. The peak for women is in their late 80s when the rate reaches 27 per cent.