Metformin for the Prevention of Prediabetes Progression to Type 2 Diabetes: A Systematic Review and Meta-Analysis

Objective: The aim of this meta-analysis was to explore the effectiveness of metformin in retarding the progression of pre-diabetes to type 2 diabetes (T2D). Materials and methods: A web-based search was conducted using the Cochrane Library identifying ten citations for analysis. In the pre-analysis stage, outlier detection was carried out using funnel plots, culprit citations identified using Byjat plot and influ - ence analysis. The meta-analysis was conducted using a random-effects model using relative-risk (RR) as the effect-size and prediction interval (PI) as the indicator of heterogeneity. The RR was calculated by comparing the metformin and the control arm [lifestyle modifica - tion (LSM)/placebo]. R studio (2022.07.1, Build 554) software was used for analysis. Results: A total of 8869 patients with pre-diabetes were included in the meta-analysis, with 4328 patients in the metformin arm and 4541 in the control arm (LSM/pla cebo). There was a 22% RR reduction with metformin compared to LSM/placebo with a 95% CI of 0.71-0.86. No heterogeneity was detected in the summary effect size (PI: 0.69-0.88). Subgroup analysis using the dose of metformin (low versus high) did not influence the outcome (p = 0.39) Conclusions: The addition of metformin to intensive LSM is an effective value addition in patients with pre-diabetes at high-risk of progression to T2D.