DPP4 and diabetes mellitus: Dipeptidyl-peptidase-4 (DPP-4) inhibitors, which are relatively new antidiabetic drugs that have been available since 2006, are prescribed clinically worldwide for patients with type 2 diabetes mellitus (T2DM) because of their unique insulinotropic action, low risk for hypoglycemia, and low risk for associated weight gain.[1] However, there have been concerns about the effect of DPP-4 inhibitors on cardiovascular diseases (CVDs) because of repeated reports about DPP-4 inhibitors positively or negatively influencing the cardiovascular system.[2,3]