RESUMO
BACKGROUND: We aimed to perform a meta-analysis to evaluate the effect of metformin on age-related macular degeneration. METHODS: We searched the following databases: PubMed, Scopus, and Web of Science. We included any randomized control trials, prospective and retrospective cohorts, cross-sectional studies, and case-control studies that investigated the effect of metformin on age-related macular degeneration in our meta-analysis with no age or language restrictions. Review manager software, version 5.4 was used to perform the meta-analysis. RESULTS: Ten studies were included in the meta-analysis with 1,447,470 patients included in the analysis. The pooled analysis showed no statistically significant difference between the metformin group and the non-metformin group regarding age-related macular degeneration (odds ratio [OR]â =â 0.37, confidence interval [CI]â =â (0.14-1.02), Pâ =â .05). Subgroup analysis showed no statistically significant difference between metformin group and non-metformin group regarding age-related macular degeneration in present or past metformin usage (ORâ =â 0.19, CIâ =â (0.03-1.1), Pâ =â .06), (ORâ =â 0.61, CIâ =â (0.25-1.45), Pâ =â .26), respectively, The pooled analysis showed no statistically significant difference between age-related macular degeneration group and control group regarding metformin usage (ORâ =â 0.86, CIâ =â (0.74-1.00), Pâ =â .05). The subgroup analysis showed no statistically significant difference between the age-related macular degeneration group and control group in <2 years of metformin usage and 2 years or more (ORâ =â 0.89, CIâ =â (0.52-1.52), Pâ =â .67), (ORâ =â 0.95, CIâ =â (0.82-1.10), Pâ =â .47), respectively. CONCLUSION: Our study revealed no role of metformin in decreasing age-related macular degeneration risk in past or present usage. More RCTs are needed to support our findings in evaluating the actual role of metformin in age-related macular degeneration.