Elderly patients who have advanced age-related macular degeneration (AMD) and decreased vision may be more likely to have cognitive problems, according to an Age-Related Eye Disease Study (AREDS) report published in the April issue of Archives of Ophthalmology.

In the elderly, AMD and cognitive deficits may stem from a similar pathogenesis.

Researchers for AREDS administered six cognitive function tests to 2,946 subjects (mean age: 75). The tests measured performance in various cognitive areas, such as memory.

Results showed that increased macular abnormalities and reduced visual acuity were linked with poorer average scores on the cognitive exams, despite sex, race, age, education, depression, diabetes mellitus, smoking status and hypertension. Also, patients whose visual acuity was worse than 20/40 O.U. were more likely to be cognitively impaired vs. those whose acuity was 20/40 or better.

Possible reasons for this finding, according to the researchers: 

As a person loses his or her vision, the ability to maintain relationships and participate in activities that may improve or maintain physical, mental and psychosocial well being become greatly reduced. This, in turn, may lead to cognitive problems.

AMD and cognitive debilitation are both chronic neurodegenerative disorders that affect people as they age.

AMD and cognitive debilitation may evolve along a similar pathogenesis, as the primary common characteristic between these two conditions is cell loss in the nervous system.

I don"t feel that the correlation between the macular degeneration and the cognitive deficit seems accurate, says optometrist Diane Catania, of Vision Loss Solutions, LLC, in Montgomeryville, Pa. But, I feel that patients with macular degeneration who are often elderly (and in my experience over 85) are more likely to have cognitive deficits, but from age-related factors, not solely vision-related. My patients have multiple medical conditions (i.e., heart disease, diabetes, etc.), and their visual impairment is secondary to all that.

When dealing with elderly AMD patients, its important to give them more time to digest what youre asking them to do during the exam, because youll get more accurate results, she says. I also think its a good idea to have the patient bring a family member along who can answer questions the patient may not be able to.

Clemons TE, Rankin MW, McBee WL; Age-Related Eye Disease Study Research Group. Cognitive impairment in the Age-Related Eye Disease Study: AREDS report no. 16. Arch Ophthalmol 2006 Apr;124(4):537-43.

Vol. No: 143:05Issue: 5/15/2006