As a means of early detection?
Vision problems can indicate Alzheimer’s disease
April 15, 2024, 3:32 p.m
A decline in vision is perceived as a typical sign of aging. But there is evidence that certain visual problems can also be an early indicator of Alzheimer’s or dementia, as the results of a study now show.
Vision problems can be an early sign of cognitive decline. This is what a research team discovered by analyzing data from more than 8,000 healthy people. The study results show that loss of visual sensitivity can predict dementia as early as 12 years before diagnosis. Based on their results, the researchers assume that visual processing tests, together with other neuropsychological tests, make dementia risks easier to recognize in people than before.
For their research, the team led by Eef Hogervorst from Loughborough University, UK, used data from a total of 8,623 people who were taking part in the EPIC Norfolk study. EPIC is the abbreviation for “European Prospective Investigation into Cancer”. Of the 8,623 people aged 48 to 92 years selected, 537 participants had developed dementia at the end of the study.
Special test for visual processing
The study participants first had to complete a visual test on the monitor. They were asked to press a button as quickly as possible once a triangle was formed in a field of moving dots. The researchers realized that people who later develop dementia recognize this triangle on the screen much more slowly than people who later live free of dementia.
Accordingly, vision problems could be an early sign of later dementia, as the toxic amyloid plaques associated with Alzheimer’s disease may initially affect areas of the brain associated with vision. The parts of the brain associated with memory would be damaged as the disease progresses team in a statement from the university quoted. Therefore, vision tests of this type could detect deficits before memory tests do.
Not everyone notices impaired vision
There are several aspects to the visual processing that is impaired in Alzheimer’s disease. For example, the ability to see the outlines of objects, i.e. contrast sensitivity or to distinguish between certain colors, can be reduced without those affected being aware of it. It is already known that the ability to see and differentiate the so-called blue-green spectrum is impaired early on in dementia. The control of eye movements also decreases in people who later develop Alzheimer’s, as does the ability to recognize faces. But what can you do?
The researchers, who examined the connection between eye movements and memory performance in an earlier study, are sure that future studies will be able to answer the question of whether eye movements can influence the risk of Alzheimer’s disease. However, until eye movements or visual processing speeds are used as a tool to clarify the risk of Alzheimer’s, so-called eye trackers must be cheaper and more user-friendly. The results of the investigation were in the specialist magazine “Scientific Reports” published.
About EPIC: At the beginning of EPIC study Between 1993 and 1998, more than 30,000 men and women aged 40 to 79 were recruited from 35 participating general practices in Norfolk. In addition to the findings on cancer, the so-called cohort study is also intended to understand the biology of aging. The participants have been providing data and taking part in additional health checks for over 25 years. They agreed to future linkage with information from medical records. Several studies have already been carried out for various clinical pictures.