The study found that in adults over the age of 65 years old, nearly 30% had a lower risk of developing dementia for at least 10 years after cataract surgery, compared to those individuals who did not.
According to the lead researcher of the study, Dr. Cecilia Lee, the Klorfine Family associate professor of ophthalmology at UW School of Medicine, there are a couple of hypotheses that they believe to be the reason why this is the case.
First, when someone develops cataracts, there is a clouding of the lens that is common when they age. This clouding of one’s vision means that their brains receive lower quality sensory input. Think of it like viewing the world with yellow-tinted sunglasses all of the time. Dr. Lee went on to add that individuals who develop cataracts often experience blurred vision, have trouble seeing sharp colors, and see halos around bright lights and are unable to drive at night. The risk of developing dementia is increased when the brain is not getting enough visual stimuli, because it loses neuronic connections that it once had before.
The second hypothesis as to why cataract surgery reduces the risk of developing dementia is that following surgery, patients are often getting more blue light. Some of the cells in the retina that regulates sleep cycles and that are associated with cognitive function respond well to blue light. Cataracts are known to specifically block blue light and surgery corrects this issue for patients, restoring blue light and allowing for better sleep and cognitive function.
Additionally, the study went on to add that prior studies have also shown that individuals who have improved vision tend to be more social, get more physical activity, and enjoy being outdoors, which are all helpful activities that can support dementia prevention.
The study did not provide any conclusive results on improvements for patients who have already developed memory loss or dementia prior to having cataract surgery.
However, as the medical world continues to explore the connections between our eyes and brain function, as you age and discover that you may be in need of cataract surgery, it may be a worthwhile consideration for a much bigger reason down the line.
For more information about this study, click here.