Vision changes could predict dementia 12 years before diagnosis, study says

Eye to eye, heart to heart
Loss in vision sensitivity could point to changes in the brain linked to Alzheimer's. (Getty Images)

The eyes are the window to the soul, and, according to new research, possibly the answer to predicting a dementia diagnosis way ahead of time.

Researchers from Loughborough University and the University of Cambridge have found that a loss of visual sensitivity could predict dementia 12 years before it is diagnosed.

The study, published in the journal Nature, suggests that visual problems may be an early indicator of cognitive decline. This is because amyloid plaques - proteins that form in the spaces between nerve cells in the brain - that are associated with Alzheimer’s disease may affect brain regions linked to vision, the scientists said.

As the disease progresses, parts of the brain associated with memory become damaged. But the study suggests that testing a person’s vision may provide the opportunity of finding these plaques before their memory begins to be affected by the disease.

Researchers followed the visual sensitivity of 8,623 healthy people in Norfolk over the course of more than a decade. By the end of the study, 537 people had developed dementia.

Writing in The Conversation, the study authors explained that they asked participants to take a visual sensitivity test at the start of the study, which involved pressing a button as soon as they saw a triangle forming in a field of moving dots.

By the end of the study, they found that "people who would develop dementia were much slower to see this triangle on the screen than people who would remain without dementia".

"Despite these exciting findings, treatment for memory problems using deliberate eye movements in older people has not been done that much yet," the study authors said. "Also, using deficits in eye movements as a diagnostic is not a regular feature, despite the possibilities in eye movement technology."

The publication of this study comes just weeks after recent research found that millions of people with mild cognitive impairment are going undiagnosed until it’s too late. Mild cognitive impairment can be an early sign of Alzheimer’s disease, but is widely underdiagnosed in people aged 65 and over.

Scientists, from the University of Southern California, warned that the failure to detect this early symptom "might deprive patients of an opportunity to get treated and to slow down disease progression".

Why is it crucial to get a diagnosis for Alzheimer’s as early as possible?

Close-up of a digital tablet with brain x-ray on screen.
Scientists have emphasised the importance of early detection and diagnosis for dementia. (Getty Images)

Experts have emphasised the importance of early diagnosis for Alzheimer’s and other dementia-related diseases to give people the best possible chance to live longer and better quality lives.

Dr Emer MacSweeney, consultant neuroradiologist and medical director at cognitive health provider Re:Cognition Health, tells Yahoo UK that early diagnosis is "crucial for timely intervention and access to effective treatment options".

"It allows individuals to plan for their future care and maximise the benefits of available therapies and also enables better management of symptoms and improves overall quality of life.

"An early diagnosis also enables individuals to participate in clinical trials, testing new-generation medications designed to slow down or halt the disease progression – these medications can only be accessed through clinical trials in the UK and require an early diagnosis," she adds.

Dr Johannes Uys, doctor at Broadgate GP, also believes early detection for dementia is "paramount" not just for the patient, but for those around them.

"Detecting any disease early (not just those associated with mental impairment) will give you the best chance to mitigate bad symptoms or even improve the individual’s condition.

"One of the most significant aspects of this is the fact that any treatment you provide will have a longer time to administer its effects. Additionally, it will also give doctors more opportunities to detect alternative medicines, treatments, or non-pharmacological interventions.

"Early detection also provides the family with more space to plan for the future or make important decisions while the person with dementia is still able to participate in the process."

Watch: A Minute Of Kindness: The Dementia-Friendly Barber

Early signs of Alzheimer’s to look out for:

  • Short-term memory lapses: forgetting recent events, repeating questions

  • Behavioural alterations: unexpected anger, mood swings, passivity, anxiety

  • Confusion: temporal disorientation, cognitive processing issues

  • Language difficulties: problems with word retrieval, speech impediments

  • Spatial disorientation: losing way in familiar settings

  • Impaired daily tasks: struggles with everyday normal activities

  • Cognitive challenges: money management, basic calculations

  • Misplacing items: e.g. putting keys in the freezer and not being able to retrace your steps to find them

  • Decision-making difficulties: poor judgments, dressing inappropriately

  • Visual and spatial perception issues: trouble with reading, spatial awareness

Dr MacSweeney adds: "Experiencing two or more of these symptoms warrants prompt consultation with a medical professional. While some issues may stem from treatable conditions, early Alzheimer’s detection empowers proactive measures.

"The evolving landscape of Alzheimer’s research heralds promising developments in medications aimed at slowing or halting its progression. Consequently, accessing interventions early on holds the greatest potential for mitigating symptoms effectively."

Dr Uys adds that, while people usually start to experience symptoms of dementia around the age of 65, this doesn't rule out the possibility of younger individuals having it.

"In fact, young-onset dementia can happen to those even in their 30s," he says. "The symptoms will usually be similar in that they combine memory loss, cognitive decline, and changes in personality or behaviour.

"However, there are different forms of dementia, especially among younger demographics, so it’s important to get verification from a medical professional before making assumptions."

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