Cognitive efficacy of omega‑3 fatty acids in Alzheimer's disease: A systematic review and meta‑analysis

Kalamara,Tsampika Vasileia; Dodos,Konstantinos; Georgakopoulou,Vasiliki Epameinondas; Fotakopoulos,George; Spandidos,Demetrios A.; Kapoukranidou,Dorothea

doi:10.3892/br.2025.1940

Cognitive efficacy of omega‑3 fatty acids in Alzheimer's disease: A systematic review and meta‑analysis

Authors:
- Tsampika Vasileia Kalamara
- Konstantinos Dodos
- Vasiliki Epameinondas Georgakopoulou
- George Fotakopoulos
- Demetrios A. Spandidos
- Dorothea Kapoukranidou
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Affiliations: Laboratory of Physiology, School of Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece, Department of Pathophysiology, Laiko General Hospital, National and Kapodistrian University of Athens, 11527 Athens, Greece, Department of Neurosurgery, General University Hospital of Larissa, 41221 Larissa, Greece, Laboratory of Clinical Virology, School of Medicine, University of Crete, 71003 Heraklion, Greece
Published online on: February 10, 2025 https://doi.org/10.3892/br.2025.1940
Article Number: 62
Copyright: © Kalamara et al. This is an open access article distributed under the terms of Creative Commons Attribution License.

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Abstract

Alzheimer's disease (AD), the most prevalent form of dementia, is a progressive neurodegenerative disorder characterized by a gradual decline in several domains of higher cortical function. Both preclinical and clinical research has suggested that the supplementation omega‑3 fatty acids (FAs) may have potential benefits for individuals with AD. The present study aimed to identify all randomized controlled trials (RCTs) examining the association between omega‑3 FA supplementation and cognitive function in patients with AD, using the Alzheimer's Disease Assessment Scale‑Cognitive (ADAS‑Cog) Subscale test as the primary outcome measure. A comprehensive search of the PubMed and Cochrane Library databases was conducted for all published RCTs up to December, 2023 that assessed cognition following omega‑3 FA supplementation compared to placebo. A total of five studies met the eligibility criteria and were included in the qualitative synthesis, with four of these studies being incorporated into the meta‑analysis. From these studies, data were collected from a total of 702 patients with AD, with 376 participants receiving omega‑3 FA supplementation and 326 participants receiving a placebo. The primary outcome measure was the ADAS‑Cog score. The meta‑analysis revealed that omega‑3 FA supplementation had a non‑significant impact on the ADAS‑Cog score compared to placebo, with a mean difference of 1.37 [95% confidence interval (CI) 0.00‑2.73]. The heterogeneity among the included studies was moderate (I²=35%, P=0.17). The test for overall effect (z=1.96, P=0.05) indicated no statistical significance. Therefore, it was concluded that omega‑3 FA supplementation does not significantly affect the cognitive function of adults with AD.

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