Early age-related macular degeneration, cognitive function, and dementia: the Cardiovascular Health Study.

OBJECTIVE: To describe the association of cognitive function and dementia with early age-related macular degeneration (AMD) in older individuals.

METHODS: This population-based study included 2,088 persons aged 69 to 97 years who participated in the Cardiovascular Health Study. The AMD was assessed from retinal photographs based on a modified Wisconsin AMD grading system. Cognitive function was assessed using the Digit Symbol Substitution Test (DSST) and the Modified Mini-Mental State Examination. Participants were also evaluated for dementia using detailed neuropsychological testing.

RESULTS: After controlling for age, sex, race, and study center, persons with low DSST scores (lowest quartile of scores, < or =30) were more likely to have early AMD (odds ratio, 1.38; 95% confidence interval, 1.03-1.85) than were persons with higher DSST scores. In analyses further controlling for education, systolic blood pressure, total cholesterol level, diabetes mellitus, smoking status, and apolipoprotein E genotype, this association was stronger (odds ratio, 2.00; 95% confidence interval, 1.29-3.10). There was no association of low Modified Mini-Mental State Examination scores, dementia, or Alzheimer disease with early AMD.

CONCLUSIONS: In this older population, cognitive impairment may share common age-related pathogenesis and risk factors with early AMD.