Omega-3 fatty acids and risk of cognitive decline in the elderly: a meta-analysis of randomized controlled trials


Evidence has demonstrated that omega-3 fatty acids intake may be associated with age-related cognitive decline. However, randomized controlled trials (RCTs) have drawn inconsistent conclusions. We performed a meta-analysis to assess the association between omega-3 fatty acids and risk of cognitive decline in the elderly. A strategic literature search of PubMed, EMBASE, and Cochrane Library (updated to December 2014) was performed. We retrieved six randomized controlled studies as eligible for our meta-analysis. Among these six studies, the duration time ranged from 3 to 40 months. The dose of omega-3 fatty acids (DHA + EPA) ranged from 400 to 1800 mg. The result of our meta-analysis expressed that omega-3 fatty acids statistically decrease the rate of cognitive decline in MMSE score (WMD = 0.15, [0.05, 0.25]; p = 0.003). In conclusion, our meta-analysis indicated that omega-3 fatty acids may help to prevent cognitive decline in the elderly.

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The following authors contributed substantially to conception and design (X.W. Zhang, Z.Y. Tang), data collection (W.S. Hou, M. Li), analyses and presentation of data (X. W. Zhang). All authors had full access to the data and take responsibility for their integrity. All authors agree with the manuscript as written.

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The authors declare that they have no conflict of interest.

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This article does not contain any studies with human participants or animals performed by any of the authors.

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Correspondence to Zhen-Yu Tang.

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Zhang, XW., Hou, WS., Li, M. et al. Omega-3 fatty acids and risk of cognitive decline in the elderly: a meta-analysis of randomized controlled trials. Aging Clin Exp Res 28, 165–166 (2016).

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  • Omega-3 fatty acids
  • Cognitive decline
  • Randomized controlled trial
  • Meta-analysis