Cognitive impairment in the Age-Related Eye Disease Study: AREDS report no. 16.
OBJECTIVE: To investigate potential associations between cognitive function and/or impairment and age-related macular degeneration (AMD) and visual impairment in the Age-Related Eye Disease Study (AREDS).
METHODS: The AREDS is an 11-center natural history study of AMD and age-related cataract. The AREDS Cognitive Function Battery was administered to 2946 participants. The battery consists of 6 neuropsychological tests measuring performance in several cognitive domains. The Dunnett multiple comparison test was used to identify differences by AMD and visual acuity severity. The relationship with cognitive impairment was also assessed using logistic regression.
RESULTS: Mean scores of instruments in the AREDS Cognitive Function Battery declined with increased macular abnormalities and reduced visual acuity. After adjustment for age, sex, race, education, smoking status, diabetes mellitus, hypertension, and depression, increased macular abnormalities (trend P value <.05) reduced mean cognitive function scores as measured by the Modified Mini-Mental State Examination and the Wechsler Logical Memory Scale. Reduced vision was found to be associated with reduced mean cognitive function scores as measured by the Modified Mini-Mental State Examination and letter and verbal fluency tasks. Persons with vision worse than 20/40 OU were more likely to be cognitively impaired (Modified Mini-Mental State Examination score <80) (odds ratio, 2.88 [95% confidence interval, 1.75-4.76]) compared with persons with visual acuity of 20/40 or better OU.
CONCLUSION: These data suggest a possible association of advanced AMD and visual acuity with cognitive impairment in older persons.