AIMS: Several trials have reported that dipeptidyl peptidase-4 (DPP-4) inhibitors, used to treat type 2 diabetes (T2DM), improve endothelial function. The current study investigated the effects of vildagliptin, a DPP-4 inhibitor, compared to glibenclamide on endothelial function, arterial stiffness, and blood pressure in patients with T2DM and hypertension.
METHODS: Patients aged over 35 years with T2DM and hypertension, but without cardiovascular disease, were randomly allocated to treatment with vildagliptin (n = 25) or glibenclamide (n = 25). Both groups took metformin. Endothelial function was evaluated by peripheral artery tonometry (Endo-PAT 2000) to calculate the reactive hyperemia index (RHI) and arterial stiffness. Primary outcome was change in the RHI after 12 weeks of treatment. Twenty-four-hour non-invasive ambulatory blood pressure monitoring was performed using a Mobil-O-Graph® 24-h PWA monitor. Arterial stiffness was assessed using the augmentation index corrected for 75 bpm (AIx75), pulse wave velocity (PWV) and central systolic blood pressure (cSBP).
RESULTS: There were no changes in the RHI in the vildagliptin group (before 2.35 ± 0.59; after 2.24 ± 0.60; p value = NS) or in the glibenclamide group (before 2.36 ± 0.52; after 2.34 ± 0.50; p value = NS), with no differences between groups (p value = NS). There was also no difference between vildagliptin and glibenclamide treatment in respect to AIx75 (p value = NS), cSBP (p value = NS) or PWV (p value = NS).
CONCLUSIONS: Vildagliptin and glibenclamide similarly do not change the endothelial function and arterial stiffness after 12 weeks of treatment in diabetic and hypertensive patients without cardiovascular disease. Thus, vildagliptin has a neutral effect on vascular function.