In T2D patients with CAD, FPG (p = 0.011), FPI (p < 0.001), hs-CRP (p = 0.025), biguanides + dipeptidyl peptidase-4 inhibitor (DPP4i) + insulin treatment (p = 0.008), antiplatelet agents (p = 0.003), and angiotensin-converting-enzyme inhibitor (ACEI) (p = 0.026) were all linked to IR. This evidence concerns the gene DPP4 and coronary artery disorder.