The Effectiveness of Metformin in Diabetes Prevention: A Systematic Review and Meta-Analysis

Diabetes mellitus is a growing global health concern, and prevention strategies play a crucial role in reducing its burden. Metformin has been widely studied as a potential intervention for diabetes prevention, but its overall effectiveness and impact on various populations remain unclear. This study aims to provide a comprehensive synthesis of the available evidence on the effectiveness of metformin in diabetes prevention. A systematic search was conducted in PubMed, Scopus, ScienceDirect, and Google Scholar for articles published from inception to June 2023. The reference lists of the included studies were also searched to retrieve possible additional studies. Any quantitative data were analyzed using Review Manager 5.4. A P-value of 0.05 was adopted as the significance threshold. Our analysis included 17 studies with a total sample size of 30,474. Our meta-analysis included two key analyses. First, the meta-analysis evaluating the effects of metformin on prediabetes demonstrated a significant reduction in the risk of progressing to type 2 diabetes mellitus (T2DM). The pooled odds ratio (OR) was 0.65 (95% confidence interval [CI] 0.53-0.80), indicating a 35% lower odds of developing T2DM among individuals with prediabetes who received metformin interventions compared to control groups. Secondly, the meta-analysis assessing the efficacy of metformin interventions in preventing T2DM yielded a significant reduction in the risk of developing the disease. The pooled risk ratio was 0.58 (95% CI 0.44-0.77), indicating a 42% lower risk of developing T2DM in individuals receiving metformin interventions compared to those in non-metformin intervention groups. These findings provide strong evidence for the effectiveness of metformin in preventing the progression of prediabetes to T2DM and reducing the overall incidence of the disease. The review demonstrated that metformin is effective in reducing the risk of developing diabetes mellitus among individuals at risk for the disease. The findings highlight the potential of metformin as a valuable intervention for diabetes prevention, particularly in high-risk populations.