Effect of Omega-3 Supplementation vs. Placebo on Blood Lipid Levels in Patients with Ischemic Heart Disease: A Systematic Review and Meta-Analysis

Background: Dyslipidemia is a key modifiable risk factor in ischemic heart disease (IHD), contributing significantly to atherosclerosis and cardiovascular events. Omega-3 polyunsaturated fatty acids (PUFAs) have been proposed to improve lipid profiles, but evidence remains inconsistent due to variations in study design, dosage, and patient populations. Objective: To evaluate the efficacy of omega-3 supplementation on lipid parameters (total cholesterol [TC], triglycerides [TG], LDL-C, HDL-C) in patients with IHD. Methods: A systematic search of PubMed, Cochrane Library, Web of Science, and Scopus (1988–2024) identified 10 randomized controlled trials (RCTs) involving 633 patients. Risk of bias was assessed using the Cochrane Risk of Bias tool. Meta-analysis was performed using RevMan 5.4.1, with pooled mean differences (MDs) and 95% confidence intervals (CIs). Results: Omega-3 supplementation significantly reduced TG (MD: -17.53 mg/dL, 95% CI: -30.64 to -4.41, p = 0.009) and LDL-C (MD: -9.43 mg/dL, 95% CI: -14.20 to -4.65, p = 0.0001). A trend toward TC reduction was observed (MD: -6.03 mg/dL, p = 0.05). HDL-C increased post-sensitivity analysis (MD: 1.66 mg/dL, p = 0.03). Heterogeneity was low (I² = 0–31%). Conclusion: Omega-3 supplementation improves lipid profiles in IHD patients, particularly reducing TG and LDL-C. These findings support its use as an adjunct therapy for dyslipidemia management in IHD patients. Further large-scale RCTs are needed to confirm long-term clinical benefits and optimize dosing strategies. PROSPERO Registration Number: CRD42025643552