Exploration of the optimized portrait of omega-3 polyunsaturated fatty acids in treating depression: A meta-analysis of randomized-controlled trials

Abstract

Background: According to previous studies, omega-3 polyunsaturated fatty acids (PUFAs) are controversial for the efficacy of treating depression.

Aims: This meta-analysis aims to investigate whether omega-3 PUFAs are able to treat depression, and find out the most beneficial clinical portrait.

Methods: More than two reviewers searched six registries, and 36 studies were eventually considered eligible. The PRISMA guidelines were used for data extraction, Cochrane Handbook for quality assessment, and random effects model for data pooling.

Outcomes: Significant heterogeneity and publication bias were observed. According to the results, significant efficacy was detected in the overall analysis [SMD = -0.26, 95 % CI = (-0.41, -0.11)] and several subgroups, while total daily dosage might be a potential heterogeneity source (P < 0.05). No between-group difference was observed in the rate of response [RR = 0.99, 95 % CI = (0.82, 1.20)], remission [RR = 1.17, 95 % CI = (0.92, 1.48)], and adverse events [RR = 1.07, 95 % CI = (0.90, 1.29)]. Total daily intake of eicosapentaenoic acid (EPA) and remission rate conformed to linear correlation (P < 0.05).

Conclusions: 1) Omega-3 PUFAs might be effective in treating depression; 2) For Asian patients with mild to moderate depression and no other baseline medication, over 8 weeks of omega-3 PUFAs 1000-1500 mg/day with ratio of EPA/docosahexaenoic acid (DHA) between 1:1 and 2:1 might benefit the most; 3) Omega-3 PUFAs are no superior than placebo in rates of response, remission, and adverse events. Although several limitations exist, the evidence-based information provides guidance for clinical practice and directions for further research.

Prospero registration number: CRD42023464823.

Keywords: Depression; Efficacy; Meta-analysis; Omega-3 polyunsaturated fatty acids; Therapeutics.