Twelve-week randomized study to compare the effect of vildagliptin vs. glibenclamide both added-on to metformin on endothelium function in patients with type 2 diabetes and hypertension

Randomized Study Comparing Vildagliptin vs Glibenclamide on Glucose Variability and Endothelial Function in Patients with Type 2 Diabetes Mellitus and Hypertension

BACKGROUND

Glucose variability (GV) is considered an important factor for cardiovascular disease (CVD) in patients with type 2 diabetes mellitus (T2DM). High GV causes endothelial dysfunction and increased oxidative stress. Dipeptidyl peptidase-4 (DPP-4) inhibitors may improve endothelial function and decrease GV. The aim of this study was to investigate the effects of vildagliptin, a DPP-4 inhibitor, compared with glibenclamide in GV and endothelial function in patients with T2DM and arterial hypertension.

METHODS

This is a prospective, randomized, open and drug-controlled study. Fifty patients older than 35 years with T2DM and hypertension without CVD were randomized to receive vildagliptin (n=25) or glibenclamide (n=25), both in added-on metformin. Laboratory tests and analysis of endothelial function were performed before and 12 weeks after treatment. Endothelial function, defined by reactive hyperemia index (RHI), was analyzed by peripheral artery tonometry (endo-PAT2000). GV was evaluated by capillary glucose with intermittent monitoring device, six measurements per day, for three days, before and after treatment. The median of standard deviation (SD) of mean blood glucose (MBG) was used to evaluate GV.

RESULTS

GV decreased in the vildagliptin group (35.2 to 30.7, P=0.037) but did not change with glibenclamide (37.6 to 37.5, P=0.765). Glycated hemoglobin was similar in both groups. MBG decreased only in glibenclamide group, without difference with vildagliptin group (P=0.374). There were no changes in the RHI in both groups and there was no correlation between GV and RHI (P=0.658).

CONCLUSION

Vildagliptin reduces GV; however, the action on endothelial function was not demonstrated. In addition, there was no correlation between GV and endothelial function.

Pharmacology of dipeptidyl peptidase-4 inhibitors and its use in the management of metabolic syndrome: a comprehensive review on drug repositioning

OBJECTIVES

Despite advances in our understanding of metabolic syndrome (MetS) and the treatment of each of its components separately, currently there is no single therapy approved to manage it as a single condition. Since multi-drug treatment increases drug interactions, decreases patient compliance and increases health costs, it is important to introduce single therapies that improve all of the MetS components.

EVIDENCE ACQUISITION

We conducted a PubMed, Scopus, Google Scholar, Web of Science, US FDA, utdo.ir and clinicaltrial.gov search, gathered the most relevant preclinical and clinical studies that have been published since 2010, and discussed the beneficial effects of dipeptidyl peptidase (DPP)-4 inhibitors to prevent and treat different constituent of the MetS as a single therapy. Furthermore, the pharmacology of DPP-4 inhibitors, focusing on pharmacodynamics, pharmacokinetics, drug interactions and their side effects are also reviewed.

RESULTS

DPP-4 inhibitors or gliptins are a new class of oral anti-diabetic drugs that seem safe drugs with no severe side effects, commonly GI disturbance, infection and inflammatory bowel disease. They increase mass and function of pancreatic β-cells, and insulin sensitivity in liver, muscle and adipose tissue. It has been noted that gliptin therapy decreases dyslipidemia. DPP-4 inhibitors increase fatty oxidation, and cholesterol efflux, and decrease hepatic triglyceride synthase and de novo lipogenesis. They delay gastric emptying time and lead to satiety. Besides, gliptin therapy has anti-inflammatory and anti-atherogenic impacts, and improves endothelial function and reduces vascular stiffness.

CONCLUSION

The gathered data prove the efficacy of DPP-4 inhibitors in managing MetS in some levels beyond anti-diabetic effects. This review could be a lead for designing new DPP-4 inhibitors with greatest effects on MetS in future. Introducing drugs with polypharmacologic effects could increase the patient's compliance and decrease the health cost that there is not in multi-drug therapy. Graphical abstract ᅟ.

Effect of vildagliptin versus glibenclamide on endothelial function and arterial stiffness in patients with type 2 diabetes and hypertension: a randomized controlled trial

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.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02145611, registered on 11 Jun 2013.

Cardiovascular effects of anti-diabetes drugs

INTRODUCTION

Cardiovascular disease remains the major contributor to morbidity and mortality in diabetes. From the need to reduce cardiovascular risk in diabetes and to ensure that such risk is not exacerbated by drug treatments, governmental regulators and drug manufacturers have focused on clinical trials evaluating cardiovascular outcomes.

AREAS COVERED

Findings from mechanistic and clinical trials of biguanides, sulfonylureas, thiazolidinediones, dipeptidyl peptidase-4 (DPP-4) inhibitors, glucagon-like peptide-1 (GLP-1) receptor agonists, and sodium-glucose co-transporter 2 (SGLT-2) inhibitors will be reviewed. These drug classes will be compared within the context of available cardiovascular outcomes data. Clinical implications of new study regulations will be examined.

EXPERT OPINION

Recent cardiovascular studies provide a more comprehensive evaluation of specific anti-diabetes therapy in individuals with high cardiovascular risk. Long-term effects of anti-hyperglycemic agents in patients with lower cardiovascular risk are still speculative. Historical data supports continued use of metformin as a first-line agent. DPP-4 inhibitors and GLP-1 receptor agonists appear to have neutral effects on cardiovascular outcomes. The significantly decreased cardiovascular risk associated with empagliflozin SGLT-2 inhibitor therapy is impressive and may change how practitioners prescribe add-on therapy to metformin.