Age-related eye disease and cognitive function

Abstract

Purpose: To determine whether people with age-related eye disease have lower cognitive scores than people with healthy vision.

Methods: A hospital-based cross-sectional study was performed in which 420 people aged 65 and older from the ophthalmology clinics at Maisonneuve-Rosemont Hospital (Montreal, Canada) were recruited who had age-related macular degeneration (AMD), Fuch's corneal dystrophy, or glaucoma. Patients with AMD and Fuchs had to have visual acuity in the better eye of worse than 20/40 while patients with glaucoma had to have visual field in their worse eye of at least -4 dB. Controls, recruited from the same clinics, did not have significant vision loss. Cognitive status was measured using the Mini-Mental State Exam Blind Version (range, 0-22) which excludes eight items that rely on vision. Linear regression with bootstrapped standard errors was used to adjust for demographic and medical factors.

Results: People with AMD, Fuch's corneal dystrophy, and glaucoma had lower cognitive scores, on average, than controls (P < 0.05). These relationships remained statistically significant after adjusting for factors such as age, sex, race, education, living alone, systemic comorbidities, and lens opacity.

Conclusions: People with vision loss due to three different age-related eye diseases had lower cognitive scores. Reasons for this should be explored using longitudinal studies and a full battery of cognitive tests that do not rely on vision.

Keywords: AMD; cognition; epidemiology; glaucoma.