A national strategy to improve the diagnosis and treatment of dementia will be announced today by the Government.

Ministers will admit that the system is failing hundreds of thousands of sufferers and their families. Half of all sufferers never get a formal diagnosis. Meanwhile, drugs are strictly rationed. Two thirds of the 700,000 British dementia sufferers live at home.

The decision to commission a national strategy will put dementia on the same footing as heart disease, cancer and strokes, Britain’s other main killers, which have national treatment frameworks in place.

Sube Banerjee, one of Britain’s leading experts in the field, will lead the new strategy, setting out new rules on treatment for GPs and hospitals to try to drive up standards of care in one of the fastest-growing illnesses in Britain.

Professor Banerjee, a clinician and head of mental health and ageing at the Institute of Psychiatry, King’s College London, will focus on improving the poor rate of diagnosing the condition. There is no test for dementia and doctors are not trained to recognise the symptoms. They often wrongly conclude that patients have depression or other mental conditions.

He will examine the available drug treatments and other ways to support patients. Although there is no cure for dementia, an array of drugs can slow down the progress of Alzheimer’s and other forms of the illness.

Professor Banerjee will also address the issue of stigma. Experts say that too often early symptoms are dismissed by family and medical professionals as “old age” and vital months and years are lost when the dementia could be treated.

Experts believe that dementia is the second or third biggest killer in Britain today, although it is hard to prove because it is rarely recorded as the primary cause of death. Many sufferers lose the ability to swallow food, grow weak and contract infections such as pneumonia. The infection is then recorded as the cause of death.

The subject of dementia in Britain will dominate this week. After the announcement of the new national strategy, there will be a screening on Wednesday of the controversial ITV documentary Malcolm and Barbara; Love’s Farewell, which charts the final days of the pianist and composer Malcolm Pointon. The documentary shows him reduced to a skeleton, unable to eat, speak or walk after suffering Alzheimer’s for more than 11 years.

A row has broken out over whether the programme makers misled the public by suggesting that the documentary covered Mr Pointon’s death. Filming ended three days before.

Mrs Pointon told The Times that she would release her own wish list of improvements in treatment she would like to see following the screening. “In particular I would really like dementia to be a core part of the training for doctors and in general nursing. I would also like to see the diagnostic tools which have now been developed introduced in every GP surgery,” she said.

Her husband was misdiagnosed as suffering depression during the first two years of his illness.

On Friday the High Court will give its long-awaited ruling on the decision by the National Institute for Health and Clinical Excellence to restrict access to key drugs to those suffering from moderate dementia only.

Ivan Lewis, the Health Minister, said: “The scale of our ambition must now meet the scale of the challenge as demographic realities mean dementia will impact on an increasing number of families in our society. The current system is failing too many dementia sufferers and their carers.”

Legacy of illness

700,000

people with dementia in Britain

30 years

The time in which the figure is set to double

60,000

An estimate of deaths directly attributable to the illness

One

in three people will end their life with some form of dementia

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