THE IMPACT OF OMEGA-3 SUPPLEMENTS ON THE COGNITIVE FUNCTION IN ALZHEIMER’S PATIENTS: A SYSTEMATIC REVIEW AND META-ANALYSIS
DOI:
https://doi.org/10.71000/3gy36k38Keywords:
Cognitive functions, memory, Alzheimer’s disease, eicosapentaenoic acid, docosahexaenoic acid, Alzheimer Disease, Cognition Disorders, Omega-3 Fatty Acids, Randomized Controlled TrialsAbstract
Background: Alzheimer’s disease (AD) is a progressive neurodegenerative disorder that leads to severe cognitive decline, especially in the aging population. With limited therapeutic options to reverse disease progression, nutritional interventions such as omega-3 fatty acid supplementation have been investigated for their neuroprotective potential. However, clinical findings remain inconsistent, prompting the need for a systematic synthesis of current evidence to determine the efficacy of omega-3 in improving cognitive function in AD patients.
Objective: To evaluate the impact of omega-3 supplementation on cognitive outcomes in patients with Alzheimer’s disease through a systematic review and meta-analysis.
Methods: A comprehensive literature search was conducted across PubMed, ScienceDirect, Scopus, The Cochrane Library, and Google Scholar for relevant studies published until March 2025. Eligible studies included randomized controlled trials assessing the effects of omega-3 supplements in AD patients, with outcomes measured by MMSE and ADAS-Cog. Two independent reviewers performed data extraction and quality assessment. The Cochrane RoB 2.0 tool was used to assess the methodological quality. Meta-analyses were conducted using RevMan 5.4 software under a random-effects model. Publication bias was evaluated using funnel plots. The certainty of evidence was graded using the GRADE framework.
Results: Seventeen studies met the inclusion criteria. The pooled effect size for MMSE scores was 0.10 (90% CI, -0.02 to 0.21; p=0.16; I²=0%), while for ADAS-Cog scores it was 0.24 (90% CI, -0.45 to 0.94; p=0.56; I²=0%). The pooled odds ratio for adverse events was 0.95 (90% CI, 0.80–1.14; p=0.67; I²=0%), indicating no significant safety concerns. No publication bias was identified, but several studies exhibited methodological limitations, leading to moderate certainty of evidence.
Conclusion: Omega-3 supplementation did not significantly improve cognitive function in AD patients. Its role may be better suited as part of a broader multimodal therapeutic strategy.
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