However, the SUSTAIN six trial evaluated semaglutide, a GLP-1 analog, in patients with type 2 diabetes and high cardiovascular risk and discovered that semaglutide was associated with a higher incidence of diabetic retinopathy complications compared to placebo, with a hazard ratio (HR) of 1.76, particularly in patients with pre-existing DR (Vilsbøll et al., 2018). This evidence concerns the gene GLP1R and type 2 diabetes mellitus.