Older adults with untreated sight conditions may be at an increased risk of dementia. The corresponding study was published in Aging and Mental Health.
"This study is among the first to evaluate the association between sight problems and cognitive outcomes in older adults through a comprehensive examination of all available population-based studies in English. 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.
"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,” they added.
For the study, the researchers analyzed the relationship between visual impairment and cognitive outcomes in older adults. To do so, they conducted a meta-analysis of 16 studies including 76, 373 participants, including five cross-sectional studies and 11 longitudinal studies.
In the end, they noted that people with a sight problem- whether self-reported or diagnosed- were at an increased risk of cognitive impairment and dementia. They additionally noted that those with a sight problem were 137% more likely to have cognitive impairment than those who did not have a sight problem.
From the longitudinal studies included in the analysis, they further noted that those with a sight problem at baseline were 41% more likely to develop cognitive impairment, and 44% more likely to develop dementia than those with sight problems at baseline.
The researchers concluded that their findings warrant additional research and randomized clinical trials to examine the implications of treating vision impairment, such as wearing glasses or cataract surgery, on cognitive impairment and dementia.
"Finding ways to prevent or delay the onset of dementia could help reduce its devastating impact on the lives of affected individuals and their families, especially in light of the growing burden of the disease. Identifying modifiable risk factors is the first critical step for developing effective interventions to achieve this goal," said Dr. Xu.
"Our new 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,” they concluded.