Prevalence of age-related macular degeneration in elderly Caucasians: the Tromsø Eye Study

Abstract

Purpose: To describe the sex- and age-specific prevalence of drusen, geographic atrophy, and neovascular age-related macular degeneration (AMD).

Design: Population-based, cross-sectional study.

Participants: Caucasian adults aged 65 to 87 years from the 6th Tromsø Study, a population-based study conducted in 2007-2008 in the municipality of Tromsø, Norway.

Methods: Digital color fundus photographs were graded for predominant phenotype based on drusen size, geographic atrophy, and neovascular AMD.

Main outcome measures: Age-related macular degeneration.

Results: A total of 3025 subjects participated; 89% of those were invited to the eye examinations. Gradable photographs were available for 2631 persons (mean age 72.3 years). Drusen 63-125 μm as the predominant phenotype were found in 34.9% of participants (95% confidence interval [CI], 33.1-36.8), drusen >125 μm were found in 24.1% (95% CI, 22.5-25.8), geographic atrophy was found in 1.0% of participants (95% CI, 0.6-1.4), and neovascular AMD was found in 2.5% of participants (95% CI, 1.9-3.1). Bilateral involvement of late AMD was present in 1.1% of the sample. Eyes with late AMD had a significantly lower refractive error (spherical equivalent 0.078 vs. 0.99 diopters, P<0.0001), and 42.5% of eyes had Snellen visual acuity ≤ 0.32.

Conclusions: The prevalence of AMD among the elderly persons in this study was similar to rates in other Caucasian populations. Late AMD was present in 10.9% of subjects aged 80 years or more. No sex differences in prevalence rates of large drusen or late AMD were observed. Lower refractive error was observed in eyes with late AMD than in eyes without late AMD.