Effect of Metformin on Lipid Profiles of Type 2 Diabetes Mellitus: A Meta-analysis of Randomized Controlled Trials

OBJECTIVE: The study aimed to perform a meta-analysis on randomised controlled trials to investigate the effect of metformin on lipid profiles among type 2 diabetes mellitus patients. MATERIAL AND METHODS: All published, randomised controlled trials with double blind assessment of outcome were included in the review. CLINICAL TRIALS WERE IDENTIFIED BY SEARCHING: PubMed, SCOPUS, TRIP, Clinical Trial registry and Cochrane. We included all RCT with no language restriction, published from January 2010 to January 2020. Two primary authors of this study were served as independent reviewers to assess the quality and bias risk assessment of each study by using Cochrane instrument. Pooled analysis was performed to determine the efficacy of metformin versus placebo on the body weight, total cholesterol, low-density lipoproteins, high-density lipoproteins and triglycerides. RESULTS: Overall 6 were used for Meta-analysis. All of the studies reported that groups were similar at baseline, patients were blinded to the study, the study dropout rate was described and acceptable, and studies had reports free of suggestions. The pool analysis showed significant effect of metformin on the reduction of mean bodyweight over time compared to placebo -1.66 (95%CI -1.88 to -1.44) p<0.000. No heterogeneity and effect of publication bias found with outcome variable. The data was extracted from all the six studies to analyze the overall effect. The overall effect is z = 5.40, with no heterogeneity and reported publication bias effect on outcome variable. The pooled effect showed significant reduction of mean triglyceride among patients with metformin as compared to placebo -0.24 (95%CI -0.33, -0.15) p<0.0001). CONCLUSION: This meta-analysis concluded that Metformin has significant reduction effect on body weight, Total Cholesterol, LDL and triglycerides in patients with type 2 diabetes mellitus.