Dietary fatty acid intake, plasma fatty acid levels, and the risk of age-related macular degeneration (AMD): a dose-response meta-analysis of prospective cohort studies.

ABSTRACT

PURPOSE: Previous population studies on the associations between dietary fatty acids (FAs), plasma FAs levels, and the risk of age-related macular degeneration (AMD) have yielded inconclusive results. Herein, we conducted a dose-response meta-analysis to quantitatively evaluate the associations between specific type of dietary FAs, plasma FAs on early and advanced AMD risk. METHODS: PubMed, Web of Science, and EMBASE were systematically searched for observational cohort studies published through May 2020. For highest versus lowest comparison and dose-response analyses, the relative risk (RR) estimates with a 95% confidence interval (CI) were analyzed using random effects model. RESULTS: 11 studies with 167,581 participants were included in the meta-analysis. During the follow-up periods (ranging from 3 to 28 years), 6,318 cases of AMD were recorded. Dietary intake of docosahexaenoic acid (DHA) and eicosatetraenoic acid (EPA) combined (per 1 g/day increment) were found to be negatively associated with early AMD (RR 0.67, 95% CI [0.51, 0.88]). Each 1 g/day increment of DHA (RR 0.50, 95% CI [0.32, 0.78]) and EPA (RR 0.40, 95% CI [0.18, 0.87]) was associated with a 50% and 60% reduction of early AMD risk, respectively. Plasma DHA (RR 0.72, 95% CI [0.55, 0.95]) and EPA (RR 0.57, 95% CI [0.40, 0.81]) indicated significant negative relationship with advanced AMD. CONCLUSION: Increasing dietary intake of ω-3 polyunsaturated fatty acids (PUFAs), specifically DHA and EPA, were associated with a reduced risk of early subtype of AMD, while other types of FAs did not present significant results. Further research is warranted to explore the potential association between dietary FA, plasma FA levels, and advanced subtype of AMD.