Age-related macular degeneration severity and risk of Alzheimer's disease in older adults in a prospective, community-based cohort study

Abstract

INTRODUCTION: Age-related macular degeneration (AMD) is associated with higher risk of Alzheimer's disease (AD), but how AD risk changes as AMD progresses remains unclear. METHODS: Among participants in the Adult Changes in Thought study, we characterized the worst dry and wet AMD severities experienced to date on a scale of 0 to 10 and assessed whether they were associated with AD risk. RESULTS: Among 2611 participants (550 AD cases, median 6.8 years follow-up), AD hazard was estimated to increase by 4% per one unit increase in dry and wet scores (dry: 95% confidence interval [CI] for hazard ratio [HR] 1.01 to 1.07, p = 0.01; wet: 95% CI 1.00 to 1.08, p = 0.03). HR estimates were similar among people without diagnosed AMD and were attenuated among those with diagnosed AMD. DISCUSSION: Worse AMD severity was associated with higher AD risk, with severity scores potentially offering greater clinical utility for AD risk characterization among individuals without diagnosed AMD.