According to a new study by the University of South Australia, millions of older people with poor eyesight are at risk of being misdiagnosed with mild cognitive impairment.
Cognitive tests based on vision-dependent tasks can skew the results of up to a quarter of people over the age of 50 who have undiagnosed vision problems such as cataracts or age-related macular degeneration (AMD).
Age-related macular degeneration is a major cause of vision loss for older people. It does not lead to complete loss of vision, but seriously affects people’s ability to read, drive, cook, and even recognize faces. It has nothing to do with cognition.
UniSA researchers recruited 24 participants with normal vision to complete two cognitive tests-one with vision-dependent reactive tasks, and the second based on fluent language.
Using a set of points to simulate AMD, participants scored significantly lower in a cognitive test that included response time tasks than without points. There was no statistical difference with word fluency tests when using points.
The study was published in Scientific reports.
UniSA Ph.D. Candidate Anne McNamara, who led the study, says the results are a stark reminder that the visual impairments that affect approximately 200 million people worldwide over the age of 50 unfairly affect cognitive outcomes when tests include visual ability.
“An erroneous score in cognitive tests can have devastating consequences, leading to unnecessary changes in life, work, financial or social circumstances,” says McNamara.
“For example, if an erroneous assessment has contributed to the diagnosis of a mild cognitive impairment, it can cause psychological problems, including depression and anxiety.
“People with AMD are already experiencing a lot of vision loss problems, and inaccurate cognitive assessment is an extra burden they don’t need.”
Visual impairment is often ignored in research and clinical conditionsUniSA researchers say low vision is underestimated in up to 50 percent of older people.
And with that, the figure is expected to increase accordingly population agingit is important that neuro-degenerative researchers monitor vision when assessing people’s cognition.
“Mobile applications can now be used to simulate overlays visual impairment on test materials when implementing their incentives, ”McNamara says.
“In addition, researchers can include quick and easy screening tasks before getting people to do cognitive tests. Oral assignments should also be part of the assessment.”
Ann McNamara et al., Effect of age-related macular degeneration on cognitive performance tests, Scientific reports (2022). DOI: 10.1038 / s41598-022-07924-8
University of South Australia
Citation: Poor vision is unfairly taken for brain deterioration (2022, May 10) obtained May 10, 2022 from https://medicalxpress.com/news/2022-05-poor-eyesight-unfairly-mistaken-brain.html
This document is subject to copyright. Except for any honest transaction for the purpose of private study or research, no part may be reproduced without written permission. The content is provided for informational purposes only.