Technology advancement has helped doctors better diagnose people, and according to a new study, researchers discovered that Alzheimer’s disease could be predicted with just a simple eye exam before physical symptoms appear.
The study was published on 23 August in the Journal of the American Medical Association Ophthalmology, describing a method called optical coherence tomography angiography.
Researchers studied a group of 30 individuals in their mid-70s with no physical symptoms of Alzheimer’s. After results from PET scans and samples from spinal fluid came, the team discovered that half of the individuals had elevated levels of proteins amyloid or tau which are linked to Alzheimer’s, a sign that the patients will develop dementia in the future.
The most important thing the team discovered was that the ones likely to develop Alzheimer’s had thinning in the retina – a fact which was seen previously in the autopsies of people that had Alzheimer’s disease. The co-principal investigator of the study, Rajendra Apte, who is a professor of ophthalmology and visual sciences at Washington University (St. Louis) stated:
“In the patients with elevated levels of amyloid or tau, we detected significant thinning in the center of the retina. All of us have a small area devoid of blood vessels in the center of our retinas that is responsible for our most precise vision. We found that this zone lacking blood vessels was significantly enlarged in people with preclinical Alzheimer’s disease.”
Bliss E. O’Bryhim is the first author of the study and a resident physician at Washington University’s Department of Ophthalmology and Visual Sciences, highlighting that the method could help “decide who should undergo more expensive and invasive testing for Alzheimer’s disease prior to the appearance of clinical symptoms.”
The Method Must Be Tested On Larger Groups, Said Experts
The study didn’t say if the participants that had thinning retinas developed Alzheimer’s afterward. This is why Doug Brown (who was not involved in the study), the chief policy and research officer at Alzheimer’s Society, said that the research is “fascinating,” but needs further investigation:
“Without confirming that any of the people with preclinical Alzheimer’s actually went on to develop the disease, we would need to see this carried out on a much larger group over a longer period of time to draw any firm conclusions.”
The head of research at Alzheimer’s Research U.K., Sara Imarisio, agrees with Doug Brown, adding that the eye tests used in the research are “quick, inexpensive and noninvasive,” but the researchers must test the theory in a larger group and see if the method is useful in discovering the early signs of Alzheimer’s.
The authors of the study agree that they will need to continue their work and see if the method works on a larger group. At the moment, there are only invasive tests to diagnose Alzheimer’s, and they’re usually done when symptoms start appearing, which can begin up to 20 years before signs like memory loss appears. Early detection could help slow the progression of the disease through treatment.
Rex Austinwas born and raised in Thunder Bay Ontario on the shores of Lake Superior. Apart from running his own podcast (Ice Fishing And Other “Cool” Things), he spends his time canoeing and backpacking in Northern Ontario.. As a journalist Rex has published stories for Global News (Thunder Bay) we well as Buzz Feed and Joystiq. As a contributor to Great Lakes Ledger, Rex most covers science and health stories. Contact Rexhere