In this study, metformin had a protective benefit in mortality rate when compared to sulfonylureas (HR = 0.519, CI: 0.493, 0.546) and short-acting insulins (HR = 0.372, CI: 0.364, 0.380), and though the risk of mortality was slightly higher in those on GLP-1s than those on metformin, this difference was not statistically significant (HR = 1.046, CI: 0.849, 1.289). The observed mortality benefits further support the existing literature's claims of metformin's utility as an effective therapeutic agent for patients with DM when considering mortality outcomes. Here, INS is linked to diabetes mellitus.