Detecting dementia: novel neuropsychological markers of preclinical Alzheimer’s disease

Dr Andrew Blackwell, Professor Barbara Sahakian and their colleagues at the University of Cambridge have published research on a new method of detecting the early signs of dementia.

The researchers found that two simple tests of learning and memory combined with the person's age was sufficient to calculate with 100% accuracy the probability that someone with mild memory impairment will go on to develop a diagnosis of probable Alzheimer's disease 32 months later. They are now applying this test to a non-clinic sample of the elderly population.

The Alzheimer's Society welcomes the research by Dr Andrew Blackwell and colleagues into the detection of the early signs of Alzheimer's disease.

The Society has consistently campaigned for research to facilitate and improve early detection of Alzheimer's disease and other dementia. This work is a major step forward, however it raises major ethical implications, as well as practical issues concerning treatment and care planning.

These tests are part of a screening process which might allow the testers to distinguish between the early signs of Alzheimer's and mild cognitive impairment. Currently you cannot get treatment for Alzheimer's disease, or indeed for other forms of dementia, until you have a diagnosis. You cannot get a diagnosis until your symptoms have progressed to a stage where the probable diagnosis is possible.

So there is a question about what you do with people who are told that they will develop Alzheimer's in two to three years time. What can you actually offer them in terms of medical help, drug treatments and support when they're still known not to have Alzheimer's disease?

Getting a diagnosis of dementia is devastating. At the moment, all too often, people are unprepared for the news and left without the support and follow up that they need.

These test also have implications for training and education of GPs and others in primary care, as well as other community-based health professionals such as community psychiatric nurses.

These implications include not only the application of the tests but also how information about a possible diagnosis of Alzheimer's is conveyed. A process of pre-diagnostic counselling would be essential so that each person who takes the test understands the possible implications of the outcome.

Demand for earlier treatment, care and support can be predicted as an outcome from the use of these tests. At present the NHS and social services are not able to meet the needs of people with dementia and their carers. This research is a signal to them to improve strategic planning for this group of people.

If people are worried about their memory they should go to their GP at the earliest possible stage.