Test spots dementia warning signs

A story earlier this week gave hope that a new method might be sensitive and reliable enough to help predict who will develop early memory problems that could later lead to dementia.

BBC News online reported that ‘memory and language tests can reliably reveal “hidden” early dementia’.

These tests aim to detect small slips in memory or slight loss of fluency in speech, and could help doctors monitor people coming to them with memory complaints.

It also could help researchers in this area, as Rebecca Wood, Chief Executive of the Alzheimer’s Research Trust, points out in the BBC Online piece: ‘Being able to spot and measure the initial stages of dementia is a crucial challenge if we are to improve drug testing and lay the groundwork for prevention trials.’

Oxford University researchers in the Oxford Project to Investigate Memory and Ageing (OPTIMA) were behind this study, funded by the Alzheimer's Research Trust and others. They gave a group of 241 healthy elderly volunteers regular tests that were designed to measure their use of language and their learning and memory abilities. They did this for a very long period of time: 20 years.

By following the volunteers for this length of time, the study, published in the journal Neurology, was able to show that the results of the Cambridge Cognitive Examination could reliably predict when a healthy elderly person was likely to develop mild cognitive impairment, a frequent precursor to dementia.

Professor David Smith of the Department of Physiology, Anatomy and Genetics, who led the study, explains: ‘In normal elderly people, those who perform very slightly below average in two cognitive tests (use of language, and learning and memory) are likely to convert to a state called ‘mild cognitive impairment’ sooner than those who score just above average on the tests. People with mild cognitive impairment have a high risk of developing Alzheimer’s disease later on.’

91 of the participants developed mild cognitive impairment during the study. Older people and those scoring lower on the language or memory tests were more likely to develop mild cognitive impairment more quickly.

‘These sensitive tests indicate that some changes that are marked in Alzheimer’s disease actually occur many years before the disease is apparent,’ says Professor Smith. ‘This implies that the disease process goes on for many years, but it also allows us to detect the disease long before it can be diagnosed.’

‘These simple tests could be used in memory clinics to help predict when elderly people will become cognitively impaired,’ he adds. It also raises the prospect that, should preventive methods be developed for dementia in the future, these tests could be used to identify who would benefit from early treatment.