A SIMPLE eye test could be the key to diagnosing the early stages of Alzheimer’s, scientists claim.
Sufferers might now be pinpointed well in advance of the destruction caused by the killer brain disease.
And this latest finding will give experts a better chance of keeping the crippling illness at bay for longer.
Researchers are hailing the quick and easy test because Alzheimer’s is an incurable condition and experts believe the key to tackling it – and stopping it – lies in early detection.
People could eventually be screened for dementia in much the same way they are for a range of cancers and other chronic illnesses.
At least 850,000 people in Britain have dementia with more than half suffering from Alzheimer’s. The figure is expected to soar by 1.7 million within the next 40 years as the population ages.
Research led by Lancaster University – in partnership with Royal Preston Hospital, Lancashire Teaching Hospitals NHS foundation trust – has shown that people with Alzheimer’s have difficulty with one particular type of eye tracking test.
As part of the team’s study, 18 patients with Alzheimer’s, 25 patients with Parkinson’s, 17 healthy young people and 18 healthy older people were asked to follow the movements of light on a computer. But in some instances they were asked to look away from the light.
Detailed eye-tracking measurements taken from the group showed stark contrasts in results.
Patients with Alzheimer’s made errors when they were asked to look away from the light and were unable to correct those errors.
This was despite them being able to respond perfectly normally when asked to look towards the light.
These errors were 10 times more frequent in the Alzheimer’s patients compared with the control groups.
Researchers, whose study is published in the Journal of the American Ageing Association, also measured memory function among Alzheimer’s patients who found the test difficult.
This revealed a clear correlation with lower memory function.
Dr Trevor Crawford, of the department of Psychology and the Centre for Ageing Research at Lancaster University, said these new results were potentially very exciting as they demonstrated, for the first time, a connection with the memory impairment that is so often the first noticeable symptom in Alzheimer’s disease.
He said: “The diagnosis of Alzheimer’s disease is currently heavily dependent on the results of a series of lengthy neuropsychological tests.
“However, patients with a dementia often find that these tests are difficult to complete due to a lack of clear understanding and lapse in their attention or motivation.
“The light tracking test could play a vital role in diagnosis as it allows us to identify and exclude alternative explanations of the test results.”
Alzheimer’s disease is a devastating disorder which starts many years before the symptoms begin to appear.
A toxic protein in the brain called beta amyloid is a hallmark of the disease and can build up for more than a decade before any outward signs of dementia such as confusion or memory loss.
Dr Eric Karran, director of research at Alzheimer’s Research UK, said: “This study suggests eye-tracking tests could help to highlight memory problems in Alzheimer’s. While it is unlikely Alzheimer’s could be diagnosed by a single eye test, the findings could help expand the battery of tests currently needed for diagnosis.
“It will now be important for the potential of this visual equipment to be explored in larger groups.”