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Effect of n-3 long-chain polyunsaturated fatty acids on mild cognitive impairment: a meta-analysis of randomized clinical trials

European Journal of Clinical Nutrition volume 74, pages 548–554 (2020)Cite this article

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Abstract

N-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFAs) have positive effect on cognitive function with mild cognitive impairment (MCI) is still controversial. The aim for this meta-analysis was to assess the scientific evidence published in the last 10 years on the effects of n-3 LC-PUFAs intake on MCI patients to explore whether n-3 LC-PUFAs have positive effective. A comprehensive literature search was developed using the Google Scholar, EMBASE, and PubMed database. The pooled effect for all studies was calculated using random-effects model. And the terms of weighted mean difference (WMD) with 95% confidence interval (CI) was pooled and indicated the effects. Heterogeneity was assessed by I2 statistics. A total of seven randomized clinical trials involving 213 cases of intervention and 221 cases of placebo were included in this analysis. Compared with placebo, n-3 LC-PUFAs supplements effectively improved cognition in elders with MCI (WMD = 0.85, 95% CI: 0.04–1.67, Z = 2.05, P = 0.04). Slight heterogeneity was detected across studies. Our results provided further evidence that n-3 LC-PUFAs may have beneficial effect in elderly with MCI.

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Fig. 1
Fig. 2
Fig. 3: Funnel plot with pseudo 95% confidence interval.

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Acknowledgements

This study was supported by the National Natural Science Foundation of China (nos: 81673277 and 81973154). We thank the reviewers for helpful suggestions.

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Authors and Affiliations

  1. Department of Health Statistics, School of Public Health, Shanxi Provincial Key Laboratory of Major Disease Risk Assessment, Shanxi Medical University, 56 South XinJian Road, Taiyuan, 030001, China

    Xiaoling Zhang, Xiaoyan Ge, Long Liu, Tong Wang & Hongmei Yu

  2. Department of Mathematics, School of Basic Medical Sciences, Shanxi Medical University, Taiyuan, China

    Hongjuan Han

  3. Shanxi Provincial Key Laboratory of Major Diseases Risk Assessment, Taiyuan, China

    Tong Wang & Hongmei Yu

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  1. Xiaoling Zhang
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Contributions

HY designed the literature search and analysis. XZ, HH, and XG searched the studies and performed the quality assessment of the results. XZ and LL analyzed the data and interpreted the result. XZ wrote the manuscript. HY and TW finalized the manuscript. All authors discussed and reviewed and approved the final manuscript.

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Correspondence to Hongmei Yu.

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Zhang, X., Han, H., Ge, X. et al. Effect of n-3 long-chain polyunsaturated fatty acids on mild cognitive impairment: a meta-analysis of randomized clinical trials. Eur J Clin Nutr 74, 548–554 (2020). https://doi.org/10.1038/s41430-019-0544-4

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