Even though most tasks required by daily living are mundane, the act of doing them engages the mind. Most human brainpower is used to process visual stimuli, so the very act of seeing and coordinating movements is cognitively demanding. That said, we would expect poor vision to lead to cognitive decline. A study was published in the JAMA Ophthalmology that showed just that.
Researchers at the University of Miami and Johns Hopkins looked at data collected in the Salisbury Eye Evaluation (SEE) study. This took place from 1993 to 2003, and there were over 2000 adults who participated. Researchers analyzed participants’ scores on visual acuity (VA) and the Mini Mental-State Examination (MMSE) questionnaire at several times during the study. The MMSE tests memory, orientation to time and space, attention span, language capacity, calculations and other tasks.
Past studies suggested a relationship between MMSE and VA scores, so researchers in this study wanted to see if the changes in both scores were related over time. They found correlations in both baseline MMSE and VA scores and in the rate of changes in the scores. That means those with big drops in cognitive ability also had concurrent drops in visual acuity.
In addition, researchers found that cognitive function and VA affect each other over and time. Vision has a stronger influence on cognition than the other way around. The reason for this is obvious since seniors who have compromised vision will be less likely take part in activities, like reading, which help keep the mind sharp. Not to mention, chores like cooking and cleaning will fall by the wayside because the person can’t see well.
Another study (of 600 seniors) done at the University of Michigan showed that those who have poor vision and who don’t visit an ophthalmologist are five times more likely to develop cognitive decline and nine and a half times more likely to develop Alzheimer’s.
What does this mean for patients? As the doctor, you need to stress the importance of regular eye exams, and not just to seniors. Baby Boomers and Gen X’ers need to hear this as well. Most caregivers are either Baby Boomers or Gen X’ers. In case you didn’t notice, the first cohort of Gen X’ers turned 50 in 2015. Getting the word out about the importance of eye exams will help increase the number of those getting necessary treatment. As you know, when someone receives treatment for a condition at an early stage, that can improve outcomes, which can also help stave off cognitive decline.
Come to think of it, maybe we all should make an appointment with the eye doctor very soon.
Sources:
https://www.nei.nih.gov/content/study-suggests-maintaining-good-vision-may-stave-cognitive-decline
https://www.nytimes.com/2017/09/25/well/vision-and-hearing-loss-are-tied-to-cognitive-decline.html