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


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. 3: Funnel plot with pseudo 95% confidence interval.


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

Author information

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.

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 (2019) doi:10.1038/s41430-019-0544-4

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