DPP4 and type 2 diabetes mellitus: Patients with type 2 diabetes received dietary and exercise therapy (n = 5, 18.5%), dipeptidyl peptidase-4 inhibitor (DPP4i) (n = 12, 44.4%), DPP4i, and metformin (n = 3, 11.1%), DPP4i and glinide (n = 1, 3.7%), insulin (n = 2, 7.4%), insulin and DPP4i (n = 3, 11.1%), and insulin and glucagon-like peptide-1 receptor agonist (GLP-1RA) (n = 1, 3.7%) at enrollment.