Peking University: Study finds that the risk of dementia in the elderly may increase due to vision problems

Older adults with untreated vision problems may have a higher chance of developing dementia, according to a recent systematic review and meta-analysis of 16 studies involving 76,373 people. The findings, published in Aging and Mental Health, suggest that more research is needed to determine how to prevent cognitive problems and dementia by addressing vision problems in older adults, such as wearing glasses or undergoing cataract surgery.

"This study is one of the first to evaluate the relationship between vision problems and cognitive outcomes in older adults by comprehensively examining all available population-based studies in English. Our findings add to the growing evidence that vision loss is a risk factor for developing dementia," said the study's lead author, Associate Professor Beibei Xu of the Peking University Center for Medical Informatics. "While the reasons behind this remain unclear, it suggests that diagnosing and treating eye conditions can be beneficial – both in improving a person's quality of life and potentially slowing or preventing memory loss."

In the UK, there are said to be up to one million people with dementia, and this number is expected to rise as the population ages. It is predicted that this number will increase to 1.6 million by 2050. The cost of dementia is expected to reach £56 billion by 2050, compared to £30 billion currently.

People's lives are severely affected by this condition. As the disease progresses, individuals will have more memory loss and changes in personality and behavior. They will eventually become completely dependent on others to care for themselves.

The researchers included 16 studies – including 76,373 participants, of which five cross-sectional studies and 11 longitudinal studies had been published before April 2020. From these studies, the researchers examined the relationship between visual impairment and cognitive outcomes in older adults. They found that:

Regardless of whether patients’ visual impairment was self-reported or diagnosed using objective measures, these individuals with vision problems were at increased risk for cognitive impairment and dementia;

People with vision problems are 137% more likely to have cognitive impairment than those without vision problems.

Compared with people without vision problems, people with vision problems at baseline had a 41% increased risk of cognitive impairment and a 44% increased risk of 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 given the growing burden of the disease. Identifying modifiable risk factors is a critical first step in developing effective interventions to achieve this goal," said Beibei Xu, a professor of medicine and director of the Department of Ophthalmology and the Department of Ophthalmology at the University of California, Berkeley. "Our new results highlight the importance of regular eye examinations for older adults – so that any potential problems with their vision can be detected and treated early. They also suggest that any self-reported changes in vision should not be ignored."

The researchers suggest that future studies are now necessary to examine the effectiveness of treating vision problems in older adults to prevent cognitive impairment and dementia.