Samieri C, et al. - The researchers performed this meta-analysis to examine the relation of fish intake to cognitive decline and to investigate interactions with Alzheimer's disease-related genes. They revealed that increasing fish intake was correlated with decreasing memory decline. No evidence of effect modification by Alzheimer's disease genes was found.

• This researchers examined the relation of fish intake to cognitive decline and analyzed interactions with Alzheimer's disease-related genes.
• They pooled participants from the French 3-City study and 4 US cohorts (Nurses’ Health Study, Women's Health Study, Chicago Health and Aging Project and Rush Memory and Aging Project) with diet and cognitive data (n = 23,688 Caucasians aged ≥65 years, 88% female, baseline year range, 1992-1999, median follow-up range, 3.9-9.1 years).
• Using linear mixed models, they estimated cohort-specific associations between fish and change in composite scores of global cognition and episodic memory.
• They pooled results using inverse-variance weighted meta-analysis.

• In multivariate analyses, slower decline in both global cognition and memory was observed with higher fish intake (P-trend ≤ 0.031).
• Consuming ≥4 vs <1 fish serving/week was correlated with 0.018 (95% CI: 0.004, 0.032) standard units lower rate of memory decline; an effect estimate equivalent to that found for 4 years of age.
• No comparisons of higher vs low fish intake reached statistical significance for global cognition.