Large-scale real-world analyses further reinforced these findings: a U.S. national electronic health record study of over one million individuals with type 2 diabetes revealed that semaglutide use was associated with a 70% reduced risk of AD compared to insulin (HR = 0.33, 95% CI: 0.21–0.51), and a 40% reduction compared to other GLP-1 drugs (HR = 0.59, 95% CI: 0.37–0.95) (Wang et al., 2024). This evidence concerns the gene GCG and type 2 diabetes mellitus.