Vision Loss May Indicate Higher Risk of Dementia, Study Shows

A recent study, published on July 13 in JAMA Ophthalmology, proposes a potential connection between sight loss in people aged over 71 and dementia.

Researchers at the University of Michigan in the United States conducted an analysis using data from approximately 3,000 US citizens over 71 years old, who were participants in the National Health and Aging Trends Study (NHATS), a larger research project.

The NHATS study evaluated the participants' vision, including their scores for short-distance vision, long-distance vision, and ability to discern objects against various backgrounds. Additionally, the researchers examined the NHATS study data to determine if the participants had dementia.

The findings of the study indicated that individuals experiencing sight loss were more likely to have dementia compared to those without vision problems. While sight loss is not currently recognized as one of the 12 primary risk factors for dementia, which may be preventable or influenced, such as smoking, high blood pressure, and hearing loss, the new evidence published today suggests a potential link between sight loss and dementia.

Dr. Susan Mitchell, the Head of Policy at Alzheimer's Research UK, emphasized the importance of dementia research during this critical period. She highlighted how studies like this one are crucial in identifying potential new risk factors for dementia and ultimately determining strategies to potentially prevent certain cases of dementia from occurring in the first place.

"This new study provides important new evidence linking sight loss to dementia and ties in with previous studies. But this isn't definitive, and it will be important for future studies to find out precisely what is causing this apparent link, as this will determine what, if any, potential there is for prevention,” added Dr. Susan Mitchell.

"There are several possibilities—for example, diabetes is a key risk factor for dementia, and this condition can also cause vision problems. Or it might be that there are shared pathways in the brain that cause both vision loss and a decline in memory and thinking abilities. Some cases of sight loss are preventable, and others can be treated successfully—if this link is confirmed, this could mean people who take steps to minimize sight problems as they get older could also help reduce their risk of conditions like dementia."

"In the meantime, we can all take action to protect our brain health, from keeping our hearts healthy to enjoying new activities and social interactions. If you want to know more about how your own lifestyle checks out in terms of keeping your brain healthy, you can take Alzheimer's Research UK's 'Think Brain Health check-in' by visiting https://www.alzheimersresearchuk.org/brain-health/check-in/”

Reference

Olivia J. Killeen et al, Objectively Measured Visual Impairment and Dementia Prevalence in Older Adults in the US, JAMA Ophthalmology (2023). DOI: 10.1001/jamaophthalmol.2023.2854