The The Effects of Omega-3 Fatty Acids on Cardiometabolic Indices and Inflammatory Markers in Patients with Type 2 Diabetes Mellitus: A Systematic Review and Meta-analysis of Randomized Placebo-controlled Trials
Abstract
Introduction: Type 2 diabetes mellitus (T2DM) remains a global health problem associated with cardiovascular risk. This study aims to study the effects of marine-derived omega-3 fatty acids (n3-FA), particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), on cardiometabolic indices and inflammatory markers in patients with T2DM through systematic review and metanalysis of RCTs. Methods: Systematic review was conducted on RCTs published in PubMed/MEDLINE, Scopus, Web of Science, ScienceDirect, and Cochrane Library. Risk of bias was evaluated using Cochrane RoB2. Pooled analyses were performed using random-effects model and expressed as mean differences (MD) or odds ratio (OR) with 95% confidence intervals (CI). Evidence certainty was assessed using GRADE approach. Results: Thirty-seven RCTs (n=2,423 patients) were included. n3-FA significantly improved HbA1c (MD= -0.29 [95% CI: -0.50, -0.08]; I2=92%), insulin resistance (MD= -0.53 [-0.88, -0.18]; I2=70%), BMI (MD= -0.42 [-0.76, -0.08]; I2=0%), total cholesterol (MD= -6.39 [-12.57, -0.21]; I2=74%), HDL (MD= 1.37 [0.02, 2.73]; I2=59%), triglycerides (MD= -32.55 [-46.35, -18.74]; I2=84%), TNF-α (MD= -2.97 [-5.10, -0.84]; I2=86%), and CRP (MD= -0.83 [-1.26, -0.40]; I2=70%) compared with placebo (p <0.05). No significant changes were observed in blood glucose, blood pressure, LDL, and IL-6. n3-FA was well tolerated with safety profile similar to placebo (OR= 0.84; 95% CI: 0.41–1.72). GRADE evaluation showed moderate-to-very low level of evidence. Conclusion: n3-FA associated with improvements on cardiometabolic indices (HbA1c, insulin resistance, BMI, total cholesterol, HDL, and triglycerides) and inflammatory markers (TNF-α and CRP) in T2DM patients. Interpretation should be cautious due to high heterogeneity and varying evidence certainty. Large-scale studies with rigorous methodology are needed to support clinical recommendations.