Sight problems may increase dementia, new study finds

A new systematic review and meta-analysis of 16 studies has found that older adults with untreated sight conditions may be at increased risk for dementia.

The study, published in the journal, Aging & Mental Health, was conducted by researchers at Peking University in Beijing, China. 

"Our findings add to the growing evidence that fading eyesight is a risk factor for developing dementia,” said lead author, associate professor Beibei Xu, from the Medical Informatics Center, at Peking University in a statement. “Although the reasons behind this remain unclear, it suggests that diagnosing and treating eye conditions may be beneficial – both to improve a person’s quality of life and also to potentially slow down or stop memory loss.”

The researchers examined 16 studies including 76,373 participants, with five cross-sectional studies and 11 longitudinal studies published before April 2020. From these studies, the authors investigated the relationship between visual impairment and cognitive outcomes in older adults. They found that the following:

• People with a sight problem had an increased risk of cognitive impairment and dementia, regardless of whether their visual impairment was self-reported or diagnosed using objective measures.
• The likelihood of having a cognitive impairment was 137 percent higher among people who had a sight problem compared to those who did not.
• People who had a sight problem at baseline had a 41 percent increased risk of developing cognitive impairment and a 44 percent increased risk of dementia, compared with those who did not.

Xu said that the study’s results highlight the importance of regular eye examinations for older adults – enabling any potential problems with their vision to be spotted and treated early. They also suggest that any self-reported changes to a person’s eyesight should not be ignored.

The authors recommend future research to examine the effectiveness of treating sight problems in older people to prevent cognitive impairment and dementia.