According to the World Health Organization, more than 55 million people in the world have dementia, and around 10 million people are diagnosed with this disorder each year. It has been predicted that this number will only be increasing in the future.
Latest studies have found that there is a link between the retina and the early signs of Alzheimer’s. If a person starts to show signs of cognitive impairment, it is very essential to seek early diagnosis. Experts at Healthwire are also very keen to know how retina and Alzheimer’s could be linked.
This prompt diagnosis of dementia would allow the individual and their carers the time to plan for the future and to access treatments. This lets them think that although they cannot do anything to cure the disease entirely, they can slow down the symptoms and can help manage the symptoms.
A number of tests are there to help you out in the diagnosis of dementia. These include brain scans, cognitive tests, psychiatric evaluations, and blood tests. These obviously take a long time and are costly, so much recent studies are focusing on finding faster and less-invasive methods of diagnosis.
Retinal Screening and Diagnosis of Dementia
As the biomarkers are showing promising results, and these are less-invasive tools for diagnosis, something shocking has happened. New research has shown that retinal screening may detect the signs of Alzheimer’s disease. This now makes it a potential method of diagnosis.
To add to that, a post-mortem study has found people with cognitive impairment or Alzheimer’s have many retinal changes that are not seen in the retinas of people that are healthy.
Alzheimer’s and Changes in Retina
In the study, the researchers examined retinal and brain tissue samples collected over 14 years from 88 human deceased donors with Alzheimer’s disease and mild cognitive impairment. Now, these samples were compared with people that were cognitively healthy donors.
Molecular, cellular, and structural changes in the retinas of those with Alzheimer’s were found. These changes although weren’t seen in cognitively healthy retinas.
People with Alzheimer’s have Beta-amyloid plaques in their brains and the study found high concentrations of Aβ in the retinas of people with Alzheimer’s and other mild cognitive impairments. Research has also found that Aβ42, a longer molecule form of Aβ is particularly important in AD pathology.
The study then found a high correlation between the presence of Aβ42 in the retina and cognitive impairment. The retinal biomarkers were not seen to be uniformly distributed throughout the retina. A much greater density of Aβ42 found in the inner and peripheral than the central retina.
Inflammatory Markers In The Eyes
In the study, researchers also spent time looking at the inflammatory markers present in the retinas. Microglia are immune cells, the action of which is changes in people with Alzheimer’s and other forms of dementia. Research has found that overactivated microglia increase Aβ and Tau and promote neuroinflammation.
So, in the study, the researchers found that retinal Aβ42 and microgliosis were strongly correlated with cognitive status in both men and women. However women as compared to men showed higher levels of retinal IBA1+ microgliosis.
Retinal Examination and Diagnosis
The examination of the retina along with the optic nerve can diagnose many health conditions that are seemingly not connected to the eye. These include diabetes, thyroid disorders, and hypertension. It also includes neurodegenerative disorders like multiple sclerosis.
Although there have been technological advances to date that allow finer and finer anatomic retinal evaluation and correlation with degenerative changes of Alzheimer’s disease have been described, there is not yet a technology that allows a retinal scan to diagnose Alzheimer’s disease.
The hope is that those times of technological advancement are near, but a lot of investment needs to be done in that matter.
There is still a need for a lot of research to be done on this matter. Experts say that “Research in this space is still in the early stages, and this tool must be studied in larger, more diverse populations to understand how or if retinal imaging may be a useful Alzheimer’s screening tool in all populations.”
The study conducted has still a lot to do. There is much more work that needs to be put in. The focus must entirely be on the use of methods that are important in identification. These must be non-invasive, easy to use, and relatively inexpensive for early detection of diagnosis.