Healthcare (Commonwealth Union) – A recent study from the University of Otago, New Zealand has uncovered a potential connection between eye health and the risk of developing dementia.
Researchers from the Dunedin Multidisciplinary Health and Development Study have identified that the tiny blood vessels at the back of the eye, known as the retinal microvasculature, may reveal early indicators of dementia risk.
According to co-lead researcher Dr Ashleigh Barrett-Young from the Department of Psychology, the discovery builds on earlier work by the team and gives assistance to fitting together pieces of the puzzle in understanding the way dementia begins.
While the results are still in their early stages and not yet ready for clinical use, similar research efforts are ongoing worldwide.
“Treatments for Alzheimer’s and some other forms of dementia may be most effective if they’re started early in the disease course.”
Identifying individuals who could gain from early intervention is vital, but current diagnostic tools make this challenging — something Dr Barrett-Young hopes will change with future advancements.
Standard cognitive assessments often fail to detect subtle early-stage changes, and patients might not show any noticeable symptoms. Meanwhile, more advanced options like MRI and PET scans are costly and not easily accessible.
She indicated that in their research, they examined the retina, which has a direct link to the brain.
“It’s thought that many of the disease processes in Alzheimer’s are reflected in the retina, making it a good target as a biomarker to identify people at risk of developing dementia.”
If doctors could detect diseases long before symptoms appear—giving patients a fighting chance at prevention instead of just treatment. That’s the promise of biomarkers: measurable signs in the body, like proteins in the blood or patterns in the retina, that offer clues about a person’s health risks.
Biomarkers are already transforming how we understand diseases like cancer, Alzheimer’s, and diabetes. They help researchers pinpoint early changes in the body, allowing for earlier diagnosis and more personalised treatment. But identifying and interpreting these biomarkers has long been a complex and time-consuming task.
Dr Aaron Reuben from the University of Virginia co-directed the study, highlighting one of many global research partnerships involving the University of Otago.
Appearing in the Journal of Alzheimer’s Disease, the study drew on eye imaging data collected during the Dunedin Study’s age-45 evaluations.
Recognised as New Zealand’s longest-standing longitudinal research project, the Dunedin Study is regarded internationally as one of the most comprehensive investigations into human health and development.
The eye scans showed that individuals with narrower arterioles (tiny arteries that transport blood away from the heart), wider venules (small veins receiving blood from capillaries), and thinner retinal nerve fibre layers (which transmit visual information from the eye to the brain) were more likely to be at risk for developing dementia.
Dr. Barrett-Young admitted the findings came as a bit of a surprise.
She pointed out that she did not expect venules to be linked to so many aspects of Alzheimer’s disease and it suggests they could be a valuable indicator when assessing dementia risk.
However, she cautioned against drawing premature conclusions urging people not to panic as she indicated that this research is still in its early stages, and they are not at the point where an eye scan can predict the future.
“Hopefully, one day we’ll be able to use AI methods on eye scans to give you an indication of your brain health, but we’re not there yet.”
The power of AI lies not just in speed, but in precision. Machine learning algorithms can be trained to distinguish between normal variations and genuine warning signs, reducing false positives and increasing diagnostic accuracy. In essence, AI is turning biomarkers into predictive tools, helping doctors move from reactive to proactive care.
The study was published in the Journal of Alzheimer’s Disease.
