Incidence of Age-Related Macular Degeneration in the Central Region of Portugal: The Coimbra Eye Study – Report 5

Abstract

Purpose: To describe the 6.5-year incidence and progression of age-related macular degeneration (AMD) in a coastal town of central Portugal. Methods: Population-based cohort study. Participants underwent standardized interviews and ophthalmological examination. Color fundus photographs were graded according to the International Classification and Grading System for AMD and ARM. The crude and age-standardized incidence of early and late AMD was calculated, and progression was analyzed. Results: The 6.5-year cumulative incidence of early AMD was 10.7%, and of late AMD it was 0.8%. The incidence of early AMD was 7.2, 13.1 and 17.7% for participants aged 55–64, 65–74 and 75–84 years (p < 0.001). The late AMD incidence was 0.3, 0.9 and 2.8% for the corresponding age groups (p = 0.003). The age-standardized incidence was 10.8% (95% CI, 10.74–10.80%) for early and 1.0% (95% CI, 1.00–1.02%) for late AMD. The incidence of both neovascular AMD and geographic atrophy was 0.4%. Progression occurred in 17.2% of patients. Conclusion: The early AMD incidence in a coastal town of central Portugal was found to be similar to that of major epidemiological studies of European-descent populations; however, the incidence of late AMD was lower, and further analysis on risk factors will be conducted.