A team of Chinese researchers evaluated 3,127 elderly patients in an effort to examine and understand more about the associations between cognitive function and ophthalmological parameters.

They found that while the causal relationship remains unclear, the association of lower cognitive function with under-corrected visual acuity suggests the need for earlier and more regular refraction testing in elderly patients to ensure adequate glasses are provided and vision-associated cognitive decline is reduced.

This research—part of the population-based Beijing Eye Study—used the mini-mental state examination to assess and score cognitive function.  The researchers found that the mean cognitive function score (CFS) was 26.3 ±3.7, with a prevalence breakdown as follows:

They note that better cognition was significantly associated with a better best-corrected visual acuity, smaller amount of under-corrected visual acuity, lower prevalence of primary angle-closure glaucoma and greater subfoveal choroidal thickness. They add that the prevalences of age-related macular degeneration, open-angle glaucoma, diabetic retinopathy, cataract, retinal vein occlusion and pseudoexfoliation were not significantly correlated with CFS.