The eye test that could detect Alzheimer’s a decade before symptoms strike

The saying goes that the eyes are the window to the soul, but only recently have medical experts begun to understand just how much they can reveal.

Researchers in the United Kingdom have now found that subtle changes in visual sensitivity might predict dementia up to 12 years before a formal diagnosis.

Researchers from Loughborough University in England looked at over 8000 people and followed their progress to “investigate the role of visual processing speed assessed by the Visual Sensitivity Test (VST) in identifying the risk of future dementia.”

The team found that participants with lower scores on the simple and complex VST had a higher probability of a future dementia diagnosis by a significant margin than those who did not go on to develop the disease.

While the authors of the study admit that more commonly used dementia screening tests were better at predicting future dementia risk, “the complex VST showed greater sensitivity to variables frequently associated with dementia risk,” such as education, socioeconomic status and self-reported general health.

“Therefore, visual sensitivity tests that contain different visual processing components and assess visual deficits contributing to cognitive impairment might be an effective way to identify risk for early dementia,” the authors wrote.

At the start of the study, the participants took part in a visual sensitivity test in which they had to press a button as soon as they saw a triangle forming in a field of moving dots.

The results found that the participants who would likely develop dementia were much slower to see this triangle on the screen than people who would remain dementia-free.

The team hypothesise that visual issues may be an early indicator of cognitive decline as the toxic amyloid plaques associated with Alzheimer’s disease may first affect areas of the brain associated with vision, so vision tests may discover dementia signs before memory tests do.

They added that people with Alzheimer’s can find it hard to ignore distracting stimuli, which may show up as eye-movement-control issues too.

Currently, some evidence suggests that people with dementia can have difficulty comprehending new people’s faces as they do not follow the usual pattern of scanning the face of the person they are talking to.

While these findings are exciting, the authors explain that “treatment for memory problems using deliberate eye movements in older people has not been done that much yet.”

They added that until cheaper eye trackers become available, using eye movements as a diagnostic tool for early-stage Alzheimer’s will not be possible outside the laboratory.

Meanwhile, scientists both at home and overseas are working to understand Alzheimer’s better which has recently led to a groundbreaking blood test that now boasts 90 per cent accuracy in diagnosing the condition.

The innovative blood testing method measures levels of Plasma Phospho-Tau217 and can detect Alzheimer ’s-related changes before symptoms are evident and track progression as the disease advances, making it a superior alternative to current diagnostic methods.

The study into the blood test, conducted by researchers at Lund University in Sweden, included 1,213 individuals experiencing mild memory symptoms, a potential early sign of Alzheimer’s.

Of these, 515 were evaluated in primary care and 698 in a specialist memory clinic. These patients were tested using the blood test, and the test results were then confirmed with cerebrospinal fluid tests that can indicate Alzheimer’s disease pathology.

“The blood test can determine with 90% accuracy whether a person experiencing memory loss is suffering from Alzheimer’s,” said Sebastian Palmqvist, Associate Professor of Neurology at Lund University and a consultant at Skåne University Hospital, who co-led the study with Professor Oskar Hansson.

“Early diagnosis is crucial as new treatments that slow the disease’s progression are developed.

“For example, two immunotherapies have recently been approved in the USA and are expected to be available in Europe soon. An early and accurate diagnosis is also vital for facilitating research into new treatments.”

Researchers hope the straightforward and reliable nature of the blood test will be widely adopted in healthcare settings.

“The next steps include establishing clear clinical guidelines for the blood test’s use in healthcare,” Hansson said.

“The test is already available in the USA and is likely to become available in many other countries soon.

“Initially, it will mainly be used in specialist memory clinics, and it may take approximately one to two years to implement guidelines and training in primary care.”

IMPORTANT LEGAL INFO This article is of a general nature and FYI only, because it doesn’t take into account your personal health requirements or existing medical conditions. That means it’s not personalised health advice and shouldn’t be relied upon as if it is. Before making a health-related decision, you should work out if the info is appropriate for your situation and get professional medical advice.