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Alzheimer’s could be spotted seven years before symptoms appear with simple memory test
Alzheimer’s could be spotted seven years before symptoms first appear with a simple memory test developed by University College London.
Currently 850,000 people are living with dementia in Britain a figure set to rise to more than one million by 2025.
Yet so far all drug trials to reverse the condition have failed and most scientists now believe that the disease will only be controlled by catching it early before irreversible damage has occurred.
In a new trial published in The Lancet Neurology, scientists from UCL showed that a simple memory test can pick up the very first hints of dementia, even when no other symptoms are present.
The researchers believe it is the earliest way to detect changes in someone’s cognition that lead to Alzheimer’s.
It works by testing how good memory is after a week. A group of 35 people were recruited, 21 of whom carry a mutation which puts them at much higher risk of developing Alzheimer’s in their 40s and 50s.
They were asked to remember a list of objects, the details of a diagram, and the facts of a story. In current tests people are asked to recall the details after 30 minutes. But for the new experiment, the time lag was extended to seven days.
The team found that those with the mutation and who were expected to develop Alzheimer’s within seven years, were able to pass the test at 30 minutes, but their performance dropped dramatically at seven days.
“It’s really a case of accelerated forgetting,” said Professor Nick Fox, Director of the Dementia Research Centre and Professor of Neurology at UCL.
“Many people have a feeling that something is going wrong with their memory, but when they take the current test, it doesn’t show anything. 30 minutes isn’t really enough time.
“The people who carried the mutation and are at an early stage of the disease did no worse at 30 minutes but at seven days they were quite a lot worse. The difference was really quite remarkable.”
Alzheimer’s disease is believed to be caused sticky amyloid plaques and tau proteins which build up in the brain and prevent neurons from communicating with each other.
But by the time symptoms like memory loss, personality changes and mood swings occur the damage to the brain is so bad, that it is currently impossible to treat.
Although the study was only carried out on people carrying the APP (amyloid precursor protein) genetic mutation, the scientists are confident it would also work for sporadic Alzheimer’s and could help in the future with diagnosing the condition.
Dr Phil Weston, Medical Research Centre Clinical Research Associate, said: “It appears to enable detection of Alzheimer's related memory problems much earlier than any other currently used cognitive test, with the individuals in our study being on average seven years away from the expected onset of any cognitive symptoms.
“There is great interest in developing and trialling drugs for Alzheimer's disease that are effective as early in the disease as possible, prior to significant loss of brain cells, possibly even before the onset of clinical symptoms.
“A future clinical application for this type of testing could be to help differentiate those people who have subtle memory concerns due to a neurodegenerative disease such as Alzheimer's, from those who have memory concerns due to other causes such as depression. Currently used memory tests are unable to do this.
“The study would appear to significantly advance our knowledge of the earliest cognitive changes in Alzheimer's, and offers a new useful approach to testing people both in drug trials and in the clinic.”
The team is hoping that the test could also be useful in drugs trials to show whether memory is getting worse, or being held at bay by a treatment, even when no symptoms are present.
That would allow scientists to begin testing medications far earlier, which might prevent Alzheimer’s disease ever forming.