Older adults who are at risk of dementia are often affected by cataracts, a study from the University of Washington has found that surgery to treat this eye problem could reduce the chances of developing dementia by up to 30%, effects that could last at least a decade.
The research from which this premise has been obtained is of an observational nature and has been carried out taking into account the longitudinal data of 3,038 participants over 65 years of age in the United States. This study has adjusted for a number of potential confounders and still found a strong association.
The results, published in the journal JAMA Internal Medicine, showed that those who had cataract surgery had a 30% lower risk of developing dementia from any cause compared to those who did not have surgery, also associated with less chances of having Alzheimer’s dementia specifically. This lowered risk continued for at least a decade after surgery.
It is important to continue investigating the eye-brain connection
“These results are consistent with the idea that sensory input to the brain is important for brain health. Some special cells in the retina are associated with cognition and regulate sleep cycles, and these cells respond well to blue light. Cataracts specifically block blue light, and cataract surgery could reactivate those cells,” explains Eric B. Larson, lead author of the study.
“Some special cells in the retina are associated with cognition and regulate sleep cycles, and these cells respond well to blue light”
Cataract surgery might have a protective effect due to a healthy-patient bias, whereby participants with cataract surgery might be healthier and have a lower risk of dementia. Several types of potential bias were taken into account and despite this we found strong associations between cataract surgery and a lower risk of dementia.
Furthermore, these findings corroborate the importance of further investigating the eye-brain connection in dementia. Previous work by the team has already shown a strong relationship between other retinal disorders, such as age-related macular degeneration, and the development of Alzheimer’s and dementia.
.
