Millions of older people with poor eyesight are at risk of being misdiagnosed as having mild cognitive impairment.
- Poor eyesight is unfairly confused with brain decline
- Visual impairment affects approximately 200 million people over the age of 50 worldwide
Poor eyesight in the elderly does not affect cognition: this reminder from the University of South Australia (UniSA) is important.
Indeed, for a quarter of people over the age of 50 who have undiagnosed visual problems such as cataracts or age-related macular degeneration (AMD) it could be mistaken for brain decline. This is what the researchers of the study regret.
eye disease
Age-related macular degeneration is one of the main causes of low vision in the elderly. It is an eye disease which affects the central zone of the retina and which develops from the age of 50.
Although it does not cause total vision loss, it does have a serious impact on people’s ability to read, drive, cook and even recognize faces.
Devastating consequences
This vision disorder unfairly affects cognitive scores when testing visual abilities with significant repercussions:
“A wrong score on cognitive tests can have devastating consequences, leading to unnecessary changes in a person’s life, work, finances or social circumstances.“, explains Anne Macnamara, doctoral student at UniSA, who led the study.
“For example, if an incorrect score contributed to a diagnosis of mild cognitive impairment, it could trigger psychological problems, including depression and anxiety. People with AMD already experience multiple problems due to vision loss and inaccurate cognitive assessment is an added burden they don’t need.”adds the scientist.
Simulate AMD
The UniSA researchers recruited 24 participants with normal vision to perform two cognitive tests – one involving vision-dependent and reaction time tasks and the other based on verbal fluency.
Using a set of glasses to simulate AMD, participants scored significantly lower on cognitive testing involving reaction time tasks than without the glasses. No statistical difference was found in the fluency tests with the glasses.
