Dietary Omega-3 Long-chain Polyunsaturated Fatty Acids and Risk for Age-related Macular Degeneration

Abstract

Abstract: : Purpose: To evaluate the relationship between omega n-3 long-chain polyunsaturated fatty acid (LCPUFA) intake and prevalence of age-related macular degeneration (AMD) in the Age-Related Eye Disease Study (AREDS). Methods: AREDS participants aged 60 to 80 years at enrollment (n=4,513) were included in this case-control study. All had best-corrected visual acuity of 20/32 or better in at least one eye. Information was obtained on demographic, lifestyle, and medical characteristics. AMD was graded from stereo color fundus photographs with a standardized protocol at a reading center. Subjects completed a self-administered 90-item semi-quantitative food frequency questionnaire at enrollment. Nutrient intake estimates were energy-adjusted with the nutrient density model. We used staged model building techniques with multiple logistic regression methods to evaluate the relationship of dietary LCPUFA composition with AMD status and covariates. AREDS subjects without AMD served as controls for each of 4 AMD groups: intermediate drusen, large drusen, geographic atrophy, neovascular AMD. Multivariable models were also analyzed with categories of fish intake as the primary predictor variable, since n-3 LCPUFAs are predominantly concentrated in marine products. Results: The risk for neovascular AMD was significantly decreased for the highest vs lowest quintiles of total n-3 LCPUFA intake (OR = 0.60; 95% CI, 0.40 - 0.88), after statistical adjustment for all nutrient- and nonnutrient-based covariates. This relationship also persisted for docosahexaenoic acid (DHA, C22:6n-3), an n-3 LCPUFA that is selectively accreted and retained in the photoreceptor outer segments (OR = 0.53; 95% CI, 0.35 – 0.79). Higher total fish consumption (> 2 servings of fish/week compared to no intake) was associated with a decreased risk for neovascular AMD (OR = 0.49; 95% CI, 0.28 – 0.84). This relationship also existed for > 1 four-ounce weekly serving of broiled/baked fish (OR=0.64; 95% CI, 0.44 – 0.94) or tuna (OR=0.66; 95%CI, 0.45 – 0.98). No significant relationships were found for the other AMD groups. Conclusion: Higher intake of n-3 LCPUFAs and fish was associated with decreased risk of having neovascular AMD after adjusting for nutrient- and nonnutrient-based predictors and correlates of AMD.

Keywords: age-related macular degeneration • clinical (human) or epidemiologic studies: ris • nutritional factors