Australian researchers have found that regular eye tests may help predict the risk of developing dementia.
The release from Neuroscience Research Australia (NeuRA) in NSW said dementia rates were rapidly increasing in Australia and globally, with vision problems contributing to an estimated 4.7% of the burden.
NeuRA postdoctoral research fellow in cognitive health, Dr Nikki-Anne Wilson, led the research, which examined the effect of changes to eyesight in adults over a 12-year period.
“While people are encouraged to get regular eye tests, this research highlights that vision checks are important from a cognitive perspective as well,” Dr Wilson said in the media release.
“It is normal for some loss of visual acuity to occur with age, which refers to how clearly objects can be seen from a distance. However, just as we are advised to get our blood pressure checked, we should also be getting our eyes checked too.”
The PATH through life study examined deterioration in vision and cognitive decline over 12 years.
“The relationship between visual acuity and cognitive performance was evident across multiple cognitive domains,” Dr Wilson said, highlighting the importance of maintaining good vision for overall cognitive health.
The release said that uncorrected vision loss was recently included as one of 14 key modifiable dementia risk factors by The Lancet Commission.
“A decline in vision can be caused by a range of factors, some of which are treatable. For example, cataracts, or vision decline that can be supported with the correct glasses,” Dr Wilson said.
“What the research is now showing is that identifying these changes early and addressing them may help reduce the risk of developing dementia.
“We know that the protein associated with Alzheimer’s disease can be found in both the brain and the retina,” Dr Wilson said.
“Neuroimaging findings also indicate that visual impairment results in brain changes both within and beyond parts of the brain which process vision.”
But it is important to also consider the impact that a decline in vision may have on broader psychosocial factors.
“We show for the first time that the relationship between a decline in vision and global cognitive performance may be partly explained by reduced social contact,” Dr Wilson said.
“People experiencing poorer vision may be more likely to avoid social events due to anxiety and this too may impact their cognitive performance. Our findings indicate the importance of maintaining social contact, not only because social isolation is a risk factor for dementia itself but also because it might also help to reduce the impact of other risk factors, such as poorer vision. However, further work is needed.”
You can read the paper in Aging and Mental Health here: https://www.tandfonline.com/doi/full/10.1080/13607863.2024.2430529
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