Consumption of eggs and the 15-year incidence of age-related macular degeneration

Abstract

Background and aims: A naturally rich source of lutein and zeaxanthin are eggs. There is scarce epidemiological data on the temporal association between total egg consumption and age-related macular degeneration (AMD) incidence. We aimed to establish the prospective and independent association between consumption of eggs with the incidence of AMD over a 15-year follow-up.

Methods: In this population-based cohort study of 3,654 participants aged 49 + years examined at baseline, 2034 participants had complete information on baseline egg consumption and AMD signs over 15 years. AMD was determined from retinal photographs. Egg consumption was assessed using a semi-quantitative food-frequency questionnaire. Total egg intake was calculated through summing up intakes in all forms e.g. boiled, poached, fried, scrambled and/or omelette. We summarized total egg consumption into the following categories: ≤1 egg/week; 2-4 eggs/week; 5-6 eggs/week; and ≥1 egg/day.

Results: At baseline, participants who consumed 2-4 eggs/week compared to those who consumed ≤1 egg/week (reference group) had reduced risk of incident late-stage AMD after 15 years: multivariable-adjusted odds ratio, OR, 0.51 (95% confidence intervals, CI, 0.28-0.92). Participants who consumed 2-4 eggs/week versus ≤1 egg/week at baseline had 62% reduced risk of developing neovascular AMD. Among those whose AMD onset was at or before the 10-year follow-up, consumption of 2-4 and 5-6 eggs/week was associated with 54% and 65% reduced risk of incident late AMD, respectively. When analyzed as a dichotomized variable, participants who consumed >1 egg/week versus ≤1 egg/week at baseline, had 46% reduced risk of developing late-stage AMD 15 years later: multivariable-adjusted OR 0.54 (95% CI 0.3-0.90). Non-significant associations were observed between egg consumption and incident early AMD.

Conclusions: Our findings suggest that moderate consumption of eggs significantly reduces the risk of developing incident late-stage AMD over 15 years.

Keywords: Age-related macular degeneration; Blue Mountains eye study; Eggs; Incidence.