Cardiovascular Safety of Dipeptidyl-Peptidase IV Inhibitors: A Meta-Analysis of Placebo-Controlled Randomized Trials

Targeting cluster of differentiation 26 / dipeptidyl peptidase 4 (CD26/DPP4) in organ fibrosis

Cluster of differentiation 26 (CD26)/dipeptidyl peptidase 4 (DPP4) is an exopeptidase that is expressed as a transmembrane protein in many organs but also present in a circulating soluble form. Beyond its enzymatic and costimulatory activity, CD26/DPP4 is involved in the pathogenesis of chronic fibrotic diseases across many organ types, such as liver cirrhosis, kidney fibrosis and lung fibrosis. Organ fibrosis is associated with a high morbidity and mortality, and there are no causative therapies that can effectively attenuate the progress of the disease. Growing evidence suggests that inhibiting CD26/DPP4 can modulate the profibrotic tissue microenvironment and thus reduce fibrotic changes within affected organs. This review summarizes the role of CD26/DPP4 in fibroproliferative disorders and highlights new opportunities for an antifibrotic treatment by CD26/DPP4 inhibition. As a major advantage, CD26/DPP4 inhibitors have been in safe and routine clinical use in type 2 diabetes for many years and thus qualify for repurposing to repurpose as a promising therapeutic against fibrosis. LINKED ARTICLES: This article is part of a themed issue on Translational Advances in Fibrosis as a Therapeutic Target. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v180.22/issuetoc.

Redefining diabetes mellitus treatments according to different mechanisms beyond hypoglycaemic effect

Early epidemiologic studies in type 2 diabetes suggested that the long-term risk of microvascular and macrovascular complications increase progressively as glucose concentrations rise, inspiring the pursuit of near euglycaemia as a means of preventing these complications in type 1 and type 2 diabetes. Evidence emerging over the past decade, however, showed that the aggressive efforts often needed to achieve low HbA1c levels can ultimately lead to worse clinical outcomes, greater risk of severe hypoglycaemia, and higher burden of treatment. The acknowledgment of the disappointing results obtained with therapies aimed exclusively at improving glycaemic control has led in recent years to a substantial paradigm shift in the treatment of the diabetic patient. The results obtained first with GLP-1RAs and more recently even more with SGLT2i on mortality and CV events have made it clear how other mechanisms, beyond the hypoglycaemic effect, are at the basis of the benefits observed in several cardiovascular outcome trials. And as evidence of the great revolution of thought we are experiencing, there is the recognition of gliflozins as drugs for the treatment not only of diabetic patients but also of non-diabetic patients suffering from HF, as reported in the latest ESC/HFA guidelines. Surely, we still have a lot to understand, but it is certain that this is the beginning of a new era.

Impact of DPP-4 inhibitors on plasma levels of BNP and NT-pro-BNP in type 2 diabetes mellitus

BACKGROUND

Dipeptidyl peptidase-4 inhibitors (DPP-4i) decrease glucose levels by regulating incretin peptides in type 2 diabetes mellitus (T2DM). This study aimed to determine the modulatory effect of DPP-4i on brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-pro-BNP) in patients with T2DM.

METHODS

PubMed, Embase and the Cochrane Library were systematically searched to identify randomized controlled trials (RCTs) evaluating the impact of DPP-4i on BNP or NT-pro-BNP. A fixed- or random-effects model was used for quantitative analysis, according to the heterogeneity. Sensitivity analysis and publication bias were performed using standard methods.

RESULTS

Nine trials with 3056 patients with T2DM were included. Meta-analysis revealed that DPP-4i did not significantly modulate the BNP (0.21 pg/mL, 95% CI - 2.36-2.79) or NT-pro-BNP level (- 7.34 pg/mL, 95% CI - 24.27-9.59). DPP-4i demonstrated no stronger effect on modulating BNP (5.17 pg/mL, 95% CI - 7.48-17.82) or NT-pro-BNP (- 9.95 pg/mL, 95% CI - 44.61-24.71) than active comparators. Pooled analysis was robust and stable after sensitivity analysis.

CONCLUSIONS

DPP-4i exhibits no significant effect on modulating BNP or NT-pro-BNP and shows no stronger effect than traditional antidiabetic agents in T2DM.

Heart failure in type 2 diabetes: current perspectives on screening, diagnosis and management

Type 2 diabetes is one of the most relevant risk factors for heart failure, the prevalence of which is increasing worldwide. The aim of the review is to highlight the current perspectives of the pathophysiology of heart failure as it pertains to type 2 diabetes. This review summarizes the proposed mechanistic bases, explaining the myocardial damage induced by diabetes-related stressors and other risk factors, i.e., cardiomyopathy in type 2 diabetes. We highlight the complex pathology of individuals with type 2 diabetes, including the relationship with chronic kidney disease, metabolic alterations, and heart failure. We also discuss the current criteria used for heart failure diagnosis and the gold standard screening tools for individuals with type 2 diabetes. Currently approved pharmacological therapies with primary use in type 2 diabetes and heart failure, and the treatment-guiding role of NT-proBNP are also presented. Finally, the influence of the presence of type 2 diabetes as well as heart failure on COVID-19 severity is briefly discussed.

Pleiotropic Benefits of DPP-4 Inhibitors Beyond Glycemic Control

Dipeptidyl peptidase (DPP)-4 inhibitors are oral anti-diabetic medications that block the activity of the ubiquitous enzyme DPP-4. Inhibition of this enzyme increases the level of circulating active glucagon-like peptide (GLP)-1 secreted from L-cells in the small intestine. GLP-1 increases the glucose level, dependent on insulin secretion from pancreatic β-cells; it also decreases the abnormally increased level of glucagon, eventually decreasing the blood glucose level in patients with type 2 diabetes. DPP-4 is involved in many physiological processes other than the degradation of GLP-1. Therefore, the inhibition of DPP-4 may have numerous effects beyond glucose control. In this article, we review the pleiotropic effects of DPP-4 inhibitors beyond glucose control, including their strong beneficial effects on the stress induced accelerated senescence of vascular cells, and the possible clinical implications of these effects.

Heart failure outcomes and glucagon-like peptide-1 receptor agonists: A systematic review of observational studies

AIM/OBJECTIVE

Recently, the glucagon-like peptide-1 receptor agonists (GLP-1RA) class showed a significant reduction in heart failure (HF) hospitalization in several meta-analyses of cardiovascular outcome trials (CVOTs). The objective of this systematic review is to summarize the real-world evidence regarding HF outcomes of GLP-1RAs.

METHODS

We searched the PubMed and EMBASE databases for observational studies that investigated HF outcomes of GLP-1RAs.

RESULTS

Our search yielded 10 observational studies. Of those, 7 were cohort studies, and 3 were nested case-control studies. The risk of HF was the outcome in four cohort studies. One study that compared exenatide and exenatide combined with insulin to insulin showed a reduction in HF risk in the exenatide and exenatide plus insulin groups (HR 0.34, 95% CI 0.22-0.52, p-value <0.001 and HR 0.40, 95% CI 0.32-0.50, p-value <0.001, respectively). The other three cohort studies did not show a statistically significant result. In the three cohort studies that investigated HF hospitalization as an outcome, two showed a lower rate of HF hospitalization [48 (16.7%) vs. 76 (28%), p-value <0.05 and HR 0.51, 95% CI 0.34-0.77, p = 0.002] in the GLP-1RA groups. Conversely, the remaining study showed a reduction of 14% in HF hospitalization in the dipeptidyl peptidase-4 inhibitors (DPP-4i) group compared to the GLP-1RA group (HR 0.86, 95% CI 0.83-0.90). In contrast to the cohort studies, the three nested case-control studies showed similar results of no association of GLP-1RA use and HF hospitalization with OR 0.67 (95% CI 0.32-1.42), HR 0.95 (95% CI 0.83-1.10), and OR 0.84 (95% CI 0.48-1.47), respectively.

CONCLUSION

The real-world evidence regarding the reduction in HF risk and hospitalization in GLP-1RA users is conflicting. Further well-designed, large multicenter, observational studies are needed to show clearer evidence.

Glucose-Lowering Medications and Cardiovascular Outcomes

PURPOSE OF THE REVIEW

The purpose of this review is to examine recent evidence supporting CV safety profile and improvement of CV outcomes of some of the newer classes of diabetic medications.

RECENT FINDINGS

Diabetes mellitus (DM) is associated with increased risk of cardiovascular disease (CVD). Thus, CVD management is critical in diabetic patients. Since 2008, the US Food and Drug Administration (FDA) has mandated that all newer diabetic medications should establish cardiovascular safety before it is approved for use. Diabetic medications that also lower CV risk would be a significant advancement as shown in recent studies. There are 3 new class of diabetic medications: Dipeptidyl peptidase-4 inhibitors (DPP-4), glucagon-like peptide receptor agonists (GLP-1 RA), and sodium-glucose cotransporter type 2 (SGLT 2) inhibitors which have established both CV safety and improvement in CV outcomes with some drugs. In patients with type 2 diabetes and established atherosclerotic cardiovascular disease, multiple atherosclerotic cardiovascular disease risk factors, or diabetic kidney disease, a sodium-glucose cotransporter 2 inhibitor, or a glucagon-like peptide 1 receptor agonist with demonstrated cardiovascular benefit is recommended to reduce the risk of major adverse cardiovascular events.

A comprehensive review on the antidiabetic activity of flavonoids targeting PTP1B and DPP-4: a structure-activity relationship analysis

Type 2 diabetes (T2D) is an expanding global health problem, resulting from defects in insulin secretion and/or insulin resistance. In the past few years, both protein tyrosine phosphatase 1B (PTP1B) and dipeptidyl peptidase-4 (DPP-4), as well as their role in T2D, have attracted the attention of the scientific community. PTP1B plays an important role in insulin resistance and is currently one of the most promising targets for the treatment of T2D, since no available PTP1B inhibitors were still approved. DPP-4 inhibitors are among the most recent agents used in the treatment of T2D (although its use has been associated with possible cardiovascular adverse events). The antidiabetic properties of flavonoids are well-recognized, and include inhibitory effects on the above enzymes, although hitherto not therapeutically explored. In the present study, a comprehensive review of the literature of both synthetic and natural isolated flavonoids as inhibitors of PTP1B and DPP-4 activities is made, including their type of inhibition and experimental conditions, and structure-activity relationship, covering a total of 351 compounds. We intend to provide the most favorable chemical features of flavonoids for the inhibition of PTP1B and DPP-4, gathering information for the future development of compounds with improved potential as T2D therapeutic agents.

Electronic medical records-based comparison of glycemic control efficacy between sulfonylureas and dipeptidyl peptidase-4 inhibitors added on to metformin monotherapy in patients with type 2 diabetes

Sulfonylurea (SU) and dipeptidyl peptidase-4 (DPP-4) inhibitors are most common secondary agents that are added to metformin monotherapy. Real-world studies have become increasingly important in providing evidence of treatment effectiveness in clinical practice and real-world data could help appropriate therapeutic information. Therefore, this study aims to compare the glycemic effectiveness of SU and DPP-4 inhibitors, which are added to metformin monotherapy in real clinical practice using electronic medical record (EMR) data. EMR data of type 2 diabetes patients treated at Seoul National University Hospital from December 2002 to December 2012 were retrieved and analyzed. The patients were divided into three groups: patients who maintained metformin monotherapy (M), and patients who added SU (MS) or DPP-4 inhibitors (MD) to metformin monotherapy. The mean change in HbA1c level, the proportion of patients achieving the HbA1c target < 7.0%, proportion of patients with treatment failure, and probability of treatment failure occurrence and changes in prescription were evaluated to compare glycemic control efficacy between SU and DPP-4 inhibitors. The MS showed significantly greater reduction in the Hb1Ac level than MD. The proportion of patients achieving HbA1c < 7.0% is higher in MD, whereas the proportion of patients with treatment failure was greater in MS. The probability of the treatment failure and probability of changes in the prescription were lower in MD than MS with hazard ratio of 0.499 and 0.579, respectively. In conclusion, this real-world study suggested that DPP-4 inhibitors are expected to show more durable glycemic control efficacy than SU in long-term use.

Reporting and methodological quality of systematic reviews and meta-analysis with protocols in Diabetes Mellitus Type II: A systematic review

BACKGROUND

Systematic reviews with or without meta-analyses (SR/MAs) are strongly encouraged to work from a protocol to facilitate high quality, transparent methodology. The completeness of reporting of a protocol (PRISMA-P) and manuscript (PRISMA) is essential to the quality appraisal (AMSTAR-2) and appropriate use of SR/MAs in making treatment decisions.

OBJECTIVES

The objectives of this study were to describe the completeness of reporting and quality of SR/MAs, assess the correlations between PRISMA-P, PRISMA, and AMSTAR-2, and to identify reporting characteristics between similar items of PRISMA-P and PRISMA.

METHODS

We performed a systematic review of Type 2 Diabetes Mellitus SR/MAs of hypoglycemic agents with publicly available protocols. Cochrane reviews, guidelines, and specific types of MA were excluded. Two reviewers independently, (i) searched PubMed and Embase between 1/1/2015 to 20/3/2019; (ii) identified protocols of included studies by searching the manuscript bibliography, supplementary material, PROSPERO, and Google; (iii) completed PRISMA-P, PRISMA, and AMSTAR-2 tools. Data analysis included descriptive statistics, Pearson correlation, and multivariable linear regression.

RESULTS

Of 357 relevant SR/MAs, 51 had available protocols and were included. The average score for PRISMA-P was 15.8±3.3 (66%; maximum 24) and 25.2±1.1 (93%; maximum 27) for PRISMA. The quality of SR/MAs assessed using the AMSTAR-2 tool identified an overall poor quality (63% critically low, 18% low, 8% moderate, 12% high). The correlation between the PRISMA-P and PRISMA was not significant (r = 0.264; p = 0.06). Correlation was significant between PRISMA-P and AMSTAR-2 (r = 0.333; p = 0.02) and PRISMA and AMSTAR-2 (r = 0.555; p<0.01). Discrepancies in reporting were common between similar PRISMA-P and PRISMA items.

CONCLUSION

Adherence to protocol reporting guidance was poor while manuscript reporting was comprehensive. Protocol completeness is not associated with a completely reported manuscript. Independently, PRISMA-P and PRISMA scores were weakly associated with higher quality assessments but insufficient as a surrogate for quality. Critical areas for quality improvement include protocol description, investigating causes of heterogeneity, and the impact of risk of bias on the evidence synthesis.

Pharmacological Management of Cardiac Disease in Patients with Type 2 Diabetes: Insights into Clinical Practice

BACKGROUND

Type 2 Diabetes Mellitus (T2DM) has emerged as a growing pandemic. Cardiovascular disease (CVD) constitutes another major health problem, with coronary heart disease being the leading cause of cardiovascular death. Patients with T2DM require a multilevel therapeutic approach, both for primary and secondary prevention of CVD.

OBJECTIVE

To present and summarize the most recent, highest level evidence retrieved from literature, relevant to the pharmaceutical management of CVD in T2DM.

METHODS

We conducted a comprehensive search of the literature on MEDLINE from its inception till today, primarily for relevant systematic reviews, meta-analyses and randomized controlled trials.

RESULTS

There is a trend towards more intensified therapeutic interventions in T2DM, concerning glycemic, lipid and blood pressure control. New drugs, such as sodium-glucose co-transporter 2 (SGLT-2) inhibitors, glucagon-like peptide-1 receptor agonists (GLP-1RAs) and proprotein convertase subtilisin/ kexin type 9 (PCSK9) inhibitors might evolve as key players in the management of diabetes and its complications within the next years. Classic drugs, such as those targeting the renin-angiotensinaldosterone system, statins and aspirin remain first-line treatment options, both for primary and secondary prevention of CVD. Lifestyle interventions should always be integrated into a complete therapeutic strategy in diabetic patients. Novel drugs, such as finerenone and LCZ696 have provided significant results in cardiovascular outcome studies; however, their role in T2DM has to be further elucidated.

CONCLUSION

Pharmaceutical approach of CVD in T2DM is multilevel and complex. Drug classes featuring pleiotropic effects may boost our armamentarium in the fight against CVD.

The efficacy and safety of dipeptidyl peptidase-4 inhibitors compared to other oral glucose-lowering medications in the treatment of type 2 diabetes

INTRODUCTION

The dipeptidyl peptidase-4 inhibitors (DPP-4is), which belong to the class of incretin-based medications, are recommended as second or third-line therapies in guidelines for the management of type 2 diabetes mellitus. They have a favorable drug tolerability and safety profile compared to other glucose-lowering agents.

OBJECTIVE

This review discusses data concerning the use of DPP-4is and their cardiovascular profile, and gives an updated comparison with the other oral glucose-lowering medications with regards to safety and efficacy. Currently available original studies, abstracts, reviews articles, systematic reviews and meta-analyses were included in the review.

DISCUSSION

DPP4is are moderately efficient in decreasing the HbA1c by an average of 0.5% as monotherapy, and 1.0% in combination therapy with other drugs. They have a good tolerability and safety profile compared to other glucose-lowering drugs. However, there are possible risks pertaining to acute pancreatitis and pancreatic cancer.

CONCLUSION

Cardiovascular outcome trials thus far have proven the cardiovascular safety for ischemic events in patients treated with sitagliptin, saxagliptin, alogliptin, linagliptin and vildagliptin. Data showing increased rate of hospitalisation in the case of saxagliptin did not seem to be a class effect.

Challenges and Strategies for Diabetes Management in Community-Living Older Adults

The prevalence of diabetes is increasing, especially in older people, mainly because of an increase in life expectancy. The number of comorbidities also increases with increasing age, leading to a unique diabetes phenotype in old age that includes vascular disease, physical and neuropathic complications, and mental dysfunction. These three categories of complications appear to have a synergistic effect that can lead to a vicious cycle of deterioration into disability. Early assessment and appropriate, timely interventions may delay adverse outcomes. However, this complex phenotype constitutes a great challenge for health care professionals. This article reviews the complex diabetes phenotype in old age and explores management strategies that are predominantly based on the overall functional status of patients within this heterogeneous age-group.

The Effect of Dipeptidyl Peptidase-4 Inhibitors on Macrovascular and Microvascular Complications of Diabetes Mellitus: A Systematic Review

Background

The World Health Organization estimates that diabetes is the seventh leading cause of death. Uncontrolled diabetes may cause severe consequences such as cardiovascular (CV) events (myocardial infarction, stroke, or CV mortality), lower-extremity amputations, and end-stage renal disease. Microvascular complications include retinopathy, autonomic and peripheral neuropathy, nephropathy, and diabetic ulcers. Major CV outcomes trials that were by the Food and Drug Administration for all new antihyperglycemia medications for patients at high risk for CV events were recently completed for all 4 US-marketed dipeptidyl peptidase-4 (DPP-4) inhibitors.

Objective

To present a comprehensive review of the clinical trials that evaluate macrovascular and microvascular complications reported with DPP-4 inhibitors in patients with type 2 diabetes mellitus.

Methods

In this review, we analyzed published articles in PubMed and Ovid databases between January 2008 and September 2019 that evaluated the effect of DPP-4 inhibitors on macrovascular and microvascular complications in patients with type 2 diabetes mellitus.

Results

A total of 18 studies, which included randomized controlled trials and meta-analyses were assessed. Current evidence demonstrates that the addition of DPP-4 inhibitors to standard antihyperglycemic and CV risk reduction treatment has not shown CV benefit relative to placebo in contrast to recently published studies for other medications within the glucagon-like peptide 1 agonist and sodium-glucose co-transporter 2 inhibitor classes. Notably, the potential risk for heart failure hospitalizations may exist for saxagliptin, and this effect is not extrapolated as a class effect. Based on our review, DPP-4 inhibitors may not influence microvascular complications in patients with diabetes. However, some studies have shown that saxagliptin and linagliptin may slow down the progression of albuminuria in patients with type 2 diabetes mellitus. The overall quality of the studies included in this review was high due to the inclusion of randomized controlled trials and meta-analyses.

Conclusions

DPP-4 inhibitors were found to have a neutral effect on macrovascular and microvascular complications, with the exception of saxagliptin, which may increase the risk for heart failure hospitalizations.

The therapeutic effect of B-type natriuretic peptides in acute decompensated heart failure

B-type natriuretic peptide (BNP) exhibits roles in natriuresis and diuresis, making it an ideal drug that may aid in diuresing a fluid-overloaded patient with poor or worsening renal function. Several randomized clinical trials have tested the hypothesis that infusions of pharmacological doses of BNP to acute heart failure (HF) patients may enhance decongestion and preserve renal function in this clinical setting. Unfortunately, none of these have demonstrated beneficial outcomes. The current challenge for BNP research in acute HF lies in addressing a failure of concept and a reluctance to abandon an ineffective research model. Future success will necessitate a detailed understanding of the mechanism of action of BNP, as well as better integration of basic and clinical science.

Effect of Dipeptidyl Peptidase 4 Inhibitors on Cardiovascular Events in Type-2 Diabetes Patients with Renal Impairment: A Systematic Review and Meta-analysis

BACKGROUND

Recent studies suggested that the increased risk of heart failure by DPP-4 inhibitors may have an interconnection with patients' baseline eGFR. We decided to investigate the effect of DPP-4 inhibitors and the degree of renal function on cardiovascular (CV) safety in type 2 diabetes (T2D) patients.

MATERIALS AND METHODS

Systemic search of literature that examined the DPP-4 inhibitors and reported cardiovascular outcomes in diabetes patients with renal impairment were performed. Studies were examined for inclusion criteria: Randomized controlled trials with reduced renal function taking DPP-4 inhibitors alone or in combination with other anti-diabetes agents reporting evaluable CV events for at least 24 weeks.

RESULT

Analysis of four CV outcome studies (11,789 patients with eGFR ≤60 ml/min/1.73m²) did not find any increase in primary composite endpoints with DPP-4 inhibitors in patients stratified by baseline renal function. Rate of hospitalization due to heart failure (hHF) is found to be non-inferior to placebo group in patients with renal insufficiency (RR 1.07; 95% CI, 0.96-1.20 P = 0.26). In moderate renal dysfunction, there is a significant increase in heart failure risk compared to placebo. (RR 1.27; 95% CI, 1.033 -1.5 8; P = 0.024).

CONCLUSION

Treatment with DPP-4 inhibitors did not affect the risk of cardiovascular events regardless of baseline renal function, however, an increase in the risk of hHF in moderate renal function in T2D patients with high CV risk merits careful consideration. Further research would be necessitated to reach definitive conclusion to understand the effect of declining renal function on CV safety of DPP-4 inhibitors.

Impact of vildagliptin on vascular and fibrotic remodeling of myocardium in experimental diabetic cardiomyopathy

The effect of dipeptidyl peptidase-4 inhibitors (DPP-4is) on myocardium in diabetic cardiomyopathy (DCM) remains a matter of debate. In the current study we investigated the effect of vildagliptin (VILDA, 3 mg/kg/d) on myocardium of DCM focusing on coronary microcirculation as well as on endothelial stress markers (ICAM and VCAM). We divided animals equally into 4 groups; nondiabetic (ND), VILDA per se, DCM and DCM + VILDA and their myocardium was evaluated for the fibro-vascular remodeling immunohistochemically as well as for molecular changes. VILDA had reversed the histological changes occurred in DCM including the disintegration, degeneration, and steatosis of cardiomyocytes with disappearance of the edema fluid. In addition VILDA significantly increased (p < 0.05) density of the coronary microcirculation and relieved endothelial stress. However, it did not prevent the development of fibrotic remodeling including the increased collagen deposition and the significantly upregulated (p < 0.05) corresponding genes. Therefore VILDA may have a positive impact on the microvascular remodeling, but not on fibrotic changes, in DCM.

Therapeutic Progress and Knowledge Basis on the Natriuretic Peptide System in Heart Failure

Notwithstanding substantial improvements in diagnosis and treatment, Heart Failure (HF) remains a major disease burden with high prevalence and poor outcomes worldwide. Natriuretic Peptides (NPs) modulate whole cardiovascular system and exhibit multiple cardio-protective effects, including the counteraction of the Renin-Angiotensin-Aldosterone System (RAAS) and Sympathetic Nervous System (SNS), promotion of vasodilatation and natriuresis, and inhibition of hypertrophy and fibrosis. Novel pharmacological therapies based on NPs may achieve a valuable shift in managing patients with HF from inhibiting RAAS and SNS to a reversal of neurohormonal imbalance. Enhancing NP bioavailability through exogenous NP administration and inhibiting Neutral Endopeptidase (NEP) denotes valuable therapeutic strategies for HF. On the one hand, NEP-resistant NPs may be more specific as therapeutic choices in patients with HF. On the other hand, NEP Inhibitors (NEPIs) combined with RAAS inhibitors have proved to exert beneficial effects and reduce adverse events in patients with HF. Highly effective and potentially safe Angiotensin Receptor Blocker Neprilysin Inhibitors (ARNIs) have been developed after the failure of NEPIs and Vasopeptidase Inhibitors (VPIs) due to lacking efficacy and safety. Therapeutic progress and knowledge basis on the NP system in HF are summarized in the current review.

Pathological Role of Advanced Glycation End Products (AGEs) and their Receptor Axis in Atrial Fibrillation

Accumulating evidence has shown that the incidence of atrial fibrillation (AF) is higher in patients with diabetes, especially those with poor glycemic control or long disease duration. Nonenzymatic glycation of amino acids of proteins, lipids, and nucleic acids has progressed under normal aging process and/or diabetic condition, which could lead to the formation and accumulation of advanced glycation end products (AGEs). AGEs not only alter the tertiary structure and physiological function of macromolecules, but also evoke inflammatory and fibrotic reactions through the interaction of cell surface receptor for AGEs (RAGE), thereby being involved in aging-related disorders. In this paper, we briefly review the association of chronic hyperglycemia and type 1 diabetes with the risk of AF and then discuss the pathological role of AGE-RAGE axis in AF and its thromboembolic complications.

Update on Cardiovascular Safety of Incretin-Based Therapy in Adults With Type 2 Diabetes Mellitus: A Meta-Analysis of Cardiovascular Outcome Trials

OBJECTIVES

The authors of 2 large randomized trials have recently published their findings related to the effects of a glucagon-like peptide 1 receptor agonist (GLP-1RA) (the HARMONY trial) and a dipeptidyl peptidase 4 (DPP-4) inhibitor (the CARMELINA trial) on cardiovascular (CV) outcomes in patients with type 2 diabetes mellitus. In light of these new data, we conducted a systematic review and meta-analysis of GLP-1RAs and DPP-4 inhibitors in CV outcome trials to assess their CV safety in patients with type 2 diabetes.

METHODS

We conducted a comprehensive literature search in the Embase and MEDLINE databases to identify trials involving GLP-1RAs and DPP-4 inhibitors with major CV-related outcomes reported, including major adverse CV events, CV death, myocardial infarction, stroke, death from any cause and hospitalization because of heart failure. A total of 9 CV outcome trials were included. Odds ratios and 95% confidence intervals were calculated based on the Mantel-Haenszel method.

RESULTS

Relative to placebo, GLP-1RAs were associated with a statistically significant reduction in the odds of major adverse CV events (13%), CV death (12%), death from any cause (11%) and stroke (13%). DPP-4 inhibitors were comparable to placebo for all outcomes. Moreover, DPP-4 inhibitors were associated with a nonsignificant 5% increase in the odds of hospitalization from heart failure compared to placebo.

CONCLUSIONS

This meta-analysis demonstrated that GLP-1RAs were associated with a significant reduction in major adverse CV events, CV death, stroke and death from any cause, while DPP-4 inhibitors were comparable to placebo for all CV outcomes, including hospitalizations for heart failure.

DPP-4 inhibitors for the treatment of type 2 diabetes: a methodology overview of systematic reviews

AIMS

To evaluate the methodological quality of systematic reviews (SRs), and summarize evidence of important outcomes from dipeptidyl peptidase-4 inhibitors (DPP4-I) in treating type 2 diabetes mellitus (T2DM).

METHODS

We included SRs of DPP4-I for the treatment of T2DM until January, 2018 by searching the Cochrane Library, PubMed, EMBASE and three Chinese databases. We evaluated the methodological qualities with the AMSTAR (Assessing the Methodological Quality of Systematic Reviews) tool and the GRADE (The Grading of Recommendations Assessment, Development and Evaluation) approach.

RESULTS

Sixty-three SRs (a total of 2,603,140 participants) receiving DPP4-I for the treatment of T2DM were included. The results of AMSTAR showed that the lowest quality was "a list of studies (included and excluded) item" with only one (1.6%) study provided, followed by the "providing a priori design" item with only four (6.3%) studies conforming to this item, the next were "the status of publication (gray literature) used as an inclusion criterion item", with only 18 (28.9%) studies conforming to these items. Only seven (11.1%) studies scored more than nine points in AMSTAR, indicating high methodological quality. For GRADE, of the 128 outcomes, high quality evidence was provided in only 28 (21.9%), moderate in 70 (54.7%), low in 27 (21.1%), and very low in three (2.3%).

CONCLUSIONS

The methodological quality of SRs of DPP4-I for type 2 diabetes mellitus is not high and there are common areas for improvement. Furthermore, the quality of evidence level is moderate and more high quality evidence is needed.

Heart Failure Hospitalization with DPP-4 Inhibitors: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND

Heart failure hospitalization (hHF) with dipeptyl-dipeptidase-4 inhibitors (DPP-4Is) remains at the center stage since the publication of Saxagliptin Assessment of Vascular Outcomes Recorded in Patients with Diabetes Mellitus - Thrombolysis in Myocardial Infarction (SAVOR-TIMI) in 2013 showing significant increase with saxagliptin, compared to placebo. This outcome led to additional label of hHF to both saxagliptin and alogliptin in April 2016 and eventual labelling of hHF to all the four approved DPP-4Is in United States in August 2017, by US Food Drug Administration. To note, neither Trial Evaluating Cardiovascular Outcomes with Sitagliptin (TECOS), nor Cardiovascular and Renal Microvascular Outcome Study with Linagliptin (CARMELINA), showed any signals of hHF with these two agents. These developments have seriously generated an uncertainty among clinicians with regards to hHF effect of DPP-4Is in type 2 diabetic patients with high risk of cardiovascular (CV) disease.

AIMS AND OBJECTIVES

We systematically searched the database of PubMed, Embase, Cochrane Central library, ClinicalTrials.gov, and International conference presentation from the inception up to October 25, 2018 using MeSH and specific key words. We retrieved all those studies that explicitly looked for hHF as a prespecified end point and were conducted for ≥52 weeks. Subsequently, we conducted the meta-analysis using comprehensive meta-analysis software Version 3, using different sensitivity analysis to study the effect of DPP-4Is on hHF in both dedicated CV outcome trials as well as randomized controlled trials.

RESULTS

The meta-analysis of four exclusive dedicated CV outcome trials (N = 43,522) did not find significant increase in hHF with DPP-4 inhibitors (Fixed model Relative Risk [RR] 1.06; 95% Confidence Interval [CI], 0.96-1.17; P = 0.25; I²: 53.95%, tau²: 0.012, P = 0.089). Meta-analysis of all randomized controlled trials that explicitly looked for hHF for ≥52 weeks (N = 48,199) also did not show any significant increase in hHF (fixed model peto odds ratio 1.05; 95% CI 0.95-1.15, P = 0.36; I²: 43.74%, tau²: 0.016, P = 0.10).

CONCLUSIONS

This meta-analysis suggests no significant increase in hHF with DPP-4 inhibitors, although a nonsignificant heterogeneity across the trials might limit this observation.

The pleiotropic cardiovascular effects of dipeptidyl peptidase-4 inhibitors

Patients with Type 2 diabetes have an excess risk for cardiovascular disease. One of the several approaches, included in the guidelines for the management of Type 2 diabetes, is based on dipeptidyl peptidase 4 (DPP-4; also termed CD26) inhibitors, also called gliptins. Gliptins inhibit the degradation of glucagon-like peptide-1 (GLP-1): this effect is associated with increased circulating insulin-to-glucagon ratio, and a consequent reduction of HbA1c. In addition to incretin hormones, there are several proteins that may be affected by DPP-4 and its inhibition: among these some are relevant for the cardiovascular system homeostasis such as SDF-1α and its receptor CXCR4, brain natriuretic peptides, neuropeptide Y and peptide YY. In this review, we will discuss the pathophysiological relevance of gliptin pleiotropism and its translational potential.

Cardiovascular safety of DPP-4 inhibitors compared with sulphonylureas: Results of randomized controlled trials and observational studies

After failure of metformin monotherapy, another glucose-lowering agent should be added to improve glucose control. The clinician has several pharmacological choices, including the addition of a sulphonylurea (SU) or a dipeptidyl peptidase-4 inhibitor (DPP-4i). While the cardiovascular safety of SUs remains a matter of controversy, DPP-4is have proven their non-inferiority vs placebo in recent cardiovascular (CV) outcome trials. In the absence of a head-to-head CV outcome trial-the CAROLINA, comparing linagliptin with glimepiride, is still ongoing-only indirect information can be found in the literature to compare CV outcomes (major CV events, myocardial infarction, ischaemic stroke, CV death and all-cause mortality) in patients with type 2 diabetes mellitus (T2DM) treated with SUs or DPP-4is. Thus, this comprehensive review summarizes the CV outcomes (excluding heart failure) reported in meta-analyses of randomized controlled trials (RCTs) of SUs vs placebo or other glucose-lowering agents, DPP-4is vs placebo or other glucose-lowering agents and SUs vs DPP-4is in phase-II/III studies. Also, the results of observational studies reporting CV events in patients treated with either SUs or DPP-4is have been carefully examined. Overall, the CV safety of SUs appears to be poorer than that of DPP-4is in both RCTs and cohort studies. However, the results are somewhat disparate, and such heterogeneity may be explained by different patient characteristics across studies, but also perhaps by differences between various molecules in each pharmacological class. In particular, some doubt about a class effect affecting SU CV safety has been raised. The results of CAROLINA are expected to shed more light on SU CV concerns, especially compared with DPP-4is.

Efficacy and safety of saxagliptin in patients with type 2 diabetes: A systematic review and meta-analysis

OBJECTIVE

To evaluate the comparative efficacy and safety of saxagliptin for type 2 diabetes (T2D).

METHODS

A systematic search of PubMed, Embase, the Cochrane Library, Web of Science, ClinicalTrials.gov and two Chinese databases for randomized controlled trials (RCTs) comparing saxagliptin with placebo or active comparators was performed up to July 2017. A complementary search was done to cover literature until March 2018. For continuous data, estimates were pooled using inverse variance methodology to calculate weighted mean differences (WMDs). Dichotomous data were presented as Mantel-Haenzel risk ratios (RRs).

RESULTS

Thirty-nine references of 30 RCTs involving 29,938 patients were analyzed. Compared with placebo, saxagliptin significantly reduced glycated hemoglobin (HbA1c, WMD -0.52%, 95% CI -0.60 to -0.44) and fasting plasma glucose (WMD -13.78 mg/dL, 95% CI -15.31 to -12.25), and increased the proportion of patients achieving HbA1c <7% (RR 1.64, 95% CI 1.53 to 1.75). When combined with submaximal-dose metformin, saxagliptin significantly increased the proportion of patients achieving HbA1c <7% compared with acarbose (RR 2.38, 95% CI 1.17 to 4.83) and uptitrated metformin (RR 1.30, 95% CI 1.04 to 1.63). Saxagliptin was similar to other DPP-4 inhibitors but inferior to liraglutide and dapagliflozin on glycemic control. Saxagliptin significantly decreased the incidences of overall adverse events compared with acarbose (RR 0.71, 95% CI 0.57 to 0.89) and liraglutide (RR 0.41, 95% CI 0.24 to 0.71) when added to metformin. Weight gain and hypoglycemia with saxagliptin was slightly but significantly higher than placebo and lower than sulfonylureas. Saxagliptin did not increase the risk of arthralgia, heart failure, pancreatitis and other adverse events.

CONCLUSIONS

Generally, saxagliptin has similar efficacy compared with most oral antidiabetic drugs and may be more effective than acarbose, while having a better safety profile than both acarbose and sulfonylureas.

Cardiovascular Effects of New Oral Glucose-Lowering Agents: DPP-4 and SGLT-2 Inhibitors

Cardiovascular disease (CVD) is a major challenge in the management of type 2 diabetes mellitus. Glucose-lowering agents that reduce the risk of major cardiovascular events would be considered a major advance, as recently reported with liraglutide and semaglutide, 2 glucagon-like peptide-1 receptor agonists, and with empagliflozin and canagliflozin, 2 SGLT-2 (sodium-glucose cotransporter type 2) inhibitors, but not with DPP-4 (dipeptidyl peptidase-4) inhibitors. The present review is devoted to CV effects of new oral glucose-lowering agents. DPP-4 inhibitors (gliptins) showed some positive cardiac and vascular effects in preliminary studies, and initial data from phase 2 to 3 clinical trials suggested a reduction in major cardiovascular events. However, subsequent CV outcome trials with alogliptin, saxagliptin, and sitagliptin showed noninferiority but failed to demonstrate any superiority compared with placebo in patients with type 2 diabetes mellitus and high CV risk. An unexpected higher risk of hospitalization for heart failure was reported with saxagliptin. SGLT-2 inhibitors (gliflozins) promote glucosuria, thus reducing glucose toxicity and body weight, and enhance natriuresis, thus lowering blood pressure. Two CV outcome trials in type 2 diabetes mellitus patients mainly in secondary prevention showed remarkable positive results. Empagliflozin in EMPA-REG-OUTCOME (EMPAgliflozin Cardiovascular OUTCOME Events in Type 2 Diabetes Mellitus Patients) reduced major cardiovascular events, CV mortality, all-cause mortality, and hospitalization for heart failure. In CANVAS (Canagliflozin Cardiovascular Assessment Study), the reduction in CV mortality with canagliflozin failed to reach statistical significance despite a similar reduction in major cardiovascular events. The underlying protective mechanisms of SGLT-2 inhibitors remain unknown and both hemodynamic and metabolic explanations have been proposed. CVD-REAL studies (Comparative Effectiveness of Cardiovascular Outcomes in New Users of Sodium-Glucose Cotransporter-2 Inhibitors; with the limitation of an observational approach) suggested that these favorable results may be considered as a class effect shared by all SGLT-2 inhibitors (including dapagliflozin) and be extrapolated to a larger population of patients with type 2 diabetes mellitus in primary prevention. Ongoing CV outcome trials with other DPP-4 (linagliptin) and SGLT-2 (dapagliflozin, ertugliflozin) inhibitors should provide additional information about CV effects of both pharmacological classes.

The safety of gliptins : updated data in 2018

INTRODUCTION

Dipeptidyl peptidase-4 inhibitors (DPP-4is) are generally considered as glucose-lowering agents with a safe profile in type 2 diabetes.

AREAS COVERED

An updated review of recent safety data from randomised controlled trials, observational studies, meta-analyses, pharmacovigilance reports regarding alogliptin, linagliptin, saxagliptin, sitagliptin, and vildagliptin, with a special focus on risks of hypoglycemia, pancreatitis and pancreatic cancer, major cardiovascular events, hospitalisation for heart failure and other new safety issues, such as bone fractures and arthralgia. The safety of DPP-4i use in special populations, elderly patients, patients with renal impairment, liver disease or heart failure, will also be discussed.

EXPERT OPINION

The good tolerance/safety profile of DPP-4is has been largely confirmed, including in more fragile populations, with no gastrointestinal adverse effects and a minimal risk of hypoglycemia. DPP-4is appear to be associated with a small increased incidence of acute pancreatitis in placebo-controlled trials, although most observational studies are reassuring. Most recent studies with DPP-4is do not confirm the increased risk of hospitalisation for heart failure reported with saxagliptin in SAVOR-TIMI 53, but further post-marketing surveillance is still recommended. New adverse events have been reported such as arthralgia, yet a causal relationship remains unclear.

Synthesis, secretion, function, metabolism and application of natriuretic peptides in heart failure

As a family of hormones with pleiotropic effects, natriuretic peptide (NP) system includes atrial NP (ANP), B-type NP (BNP), C-type NP (CNP), dendroaspis NP and urodilatin, with NP receptor-A (guanylate cyclase-A), NP receptor-B (guanylate cyclase-B) and NP receptor-C (clearance receptor). These peptides are genetically distinct, but structurally and functionally related for regulating circulatory homeostasis in vertebrates. In humans, ANP and BNP are encoded by NP precursor A (NPPA) and NPPB genes on chromosome 1, whereas CNP is encoded by NPPC on chromosome 2. NPs are synthesized and secreted through certain mechanisms by cardiomyocytes, fibroblasts, endotheliocytes, immune cells (neutrophils, T-cells and macrophages) and immature cells (embryonic stem cells, muscle satellite cells and cardiac precursor cells). They are mainly produced by cardiovascular, brain and renal tissues in response to wall stretch and other causes. NPs provide natriuresis, diuresis, vasodilation, antiproliferation, antihypertrophy, antifibrosis and other cardiometabolic protection. NPs represent body's own antihypertensive system, and provide compensatory protection to counterbalance vasoconstrictor-mitogenic-sodium retaining hormones, released by renin-angiotensin-aldosterone system (RAAS) and sympathetic nervous system (SNS). NPs play central roles in regulation of heart failure (HF), and are inactivated through not only NP receptor-C, but also neutral endopeptidase (NEP), dipeptidyl peptidase-4 and insulin degrading enzyme. Both BNP and N-terminal proBNP are useful biomarkers to not only make the diagnosis and assess the severity of HF, but also guide the therapy and predict the prognosis in patients with HF. Current NP-augmenting strategies include the synthesis of NPs or agonists to increase NP bioactivity and inhibition of NEP to reduce NP breakdown. Nesiritide has been established as an available therapy, and angiotensin receptor blocker NEP inhibitor (ARNI, LCZ696) has obtained extremely encouraging results with decreased morbidity and mortality. Novel pharmacological approaches based on NPs may promote a therapeutic shift from suppressing the RAAS and SNS to re-balancing neuroendocrine dysregulation in patients with HF. The current review discussed the synthesis, secretion, function and metabolism of NPs, and their diagnostic, therapeutic and prognostic values in HF.

Plasma dipeptidyl-peptidase-4 activity is associated with left ventricular systolic function in patients with ST-segment elevation myocardial infarction

Plasma dipeptidyl-peptidase-4 activity (DPP4a) is inversely associated with left ventricular function in patients with heart failure (HF) or diabetes. However, the association between DPP4a and left ventricular function in ST-segment elevation myocardial infarction (STEMI) patients has not been reported. We studied this association in 584 consecutive STEMI patients at a tertiary referral center from July 2014 to October 2015. DPP4a and plasma N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) levels were quantified by enzymatic assays. The median serum NT-proBNP levels were highest in patients of the lowest tertile (T1) of DPP4a compared with that of the highest tertile (T3) (p = 0.028). The STEMI patients in T1 exhibited lower left ventricular systolic function (T1 vs. T3: left ventricular ejection fraction (LVEF): 50.13 ± 9.12 vs. 52.85 ± 6.82%, p = 0.001). Multivariate logistic-regression analyses (adjusted for confounding variables) showed that a 1 U/L increase in DPP4a was associated with a decreased incidence of left ventricular systolic dysfunction (LVSD) (adjusted odds ratio: 0.90; 95% CI: 0.87–0.94; p < 0.01). In conclusion, low DPP4a is independently associated with LVSD in STEMI patients, which suggests that DPP4 may be involved in the mechanisms of LVSD in STEMI patients.

Dipeptidyl-peptidase (DPP)-4 inhibitors and glucagon-like peptide (GLP)-1 analogues for prevention or delay of type 2 diabetes mellitus and its associated complications in people at increased risk for the development of type 2 diabetes mellitus

BACKGROUND

The projected rise in the incidence of type 2 diabetes mellitus (T2DM) could develop into a substantial health problem worldwide. Whether dipeptidyl-peptidase (DPP)-4 inhibitors or glucagon-like peptide (GLP)-1 analogues are able to prevent or delay T2DM and its associated complications in people at risk for the development of T2DM is unknown.

OBJECTIVES

To assess the effects of DPP-4 inhibitors and GLP-1 analogues on the prevention or delay of T2DM and its associated complications in people with impaired glucose tolerance, impaired fasting blood glucose, moderately elevated glycosylated haemoglobin A1c (HbA1c) or any combination of these.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials; MEDLINE; PubMed; Embase; ClinicalTrials.gov; the World Health Organization (WHO) International Clinical Trials Registry Platform; and the reference lists of systematic reviews, articles and health technology assessment reports. We asked investigators of the included trials for information about additional trials. The date of the last search of all databases was January 2017.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) with a duration of 12 weeks or more comparing DPP-4 inhibitors and GLP-1 analogues with any pharmacological glucose-lowering intervention, behaviour-changing intervention, placebo or no intervention in people with impaired fasting glucose, impaired glucose tolerance, moderately elevated HbA1c or combinations of these.

DATA COLLECTION AND ANALYSIS

Two review authors read all abstracts and full-text articles and records, assessed quality and extracted outcome data independently. One review author extracted data which were checked by a second review author. We resolved discrepancies by consensus or the involvement of a third review author. For meta-analyses, we planned to use a random-effects model with investigation of risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes, using 95% confidence intervals (CIs) for effect estimates. We assessed the overall quality of the evidence using the GRADE instrument.

MAIN RESULTS

We included seven completed RCTs; about 98 participants were randomised to a DPP-4 inhibitor as monotherapy and 1620 participants were randomised to a GLP-1 analogue as monotherapy. Two trials investigated a DPP-4 inhibitor and five trials investigated a GLP-1 analogue. A total of 924 participants with data on allocation to control groups were randomised to a comparator group; 889 participants were randomised to placebo and 33 participants to metformin monotherapy. One RCT of liraglutide contributed 85% of all participants. The duration of the intervention varied from 12 weeks to 160 weeks. We judged none of the included trials at low risk of bias for all 'Risk of bias' domains and did not perform meta-analyses because there were not enough trials.One trial comparing the DPP-4 inhibitor vildagliptin with placebo reported no deaths (very low-quality evidence). The incidence of T2DM by means of WHO diagnostic criteria in this trial was 3/90 participants randomised to vildagliptin versus 1/89 participants randomised to placebo (very low-quality evidence). Also, 1/90 participants on vildagliptin versus 2/89 participants on placebo experienced a serious adverse event (very low-quality evidence). One out of 90 participants experienced congestive heart failure in the vildagliptin group versus none in the placebo group (very low-quality evidence). There were no data on non-fatal myocardial infarction, stroke, health-related quality of life or socioeconomic effects reported.All-cause and cardiovascular mortality following treatment with GLP-1 analogues were rarely reported; one trial of exenatide reported that no participant died. Another trial of liraglutide 3.0 mg showed that 2/1501 in the liraglutide group versus 2/747 in the placebo group died after 160 weeks of treatment (very low-quality evidence).The incidence of T2DM following treatment with liraglutide 3.0 mg compared to placebo after 160 weeks was 26/1472 (1.8%) participants randomised to liraglutide versus 46/738 (6.2%) participants randomised to placebo (very low-quality evidence). The trial established the risk for (diagnosis of) T2DM as HbA1c 5.7% to 6.4% (6.5% or greater), fasting plasma glucose 5.6 mmol/L or greater to 6.9 mmol/L or less (7.0 mmol/L or greater) or two-hour post-load plasma glucose 7.8 mmol/L or greater to 11.0 mmol/L (11.1 mmol/L). Altogether, 70/1472 (66%) participants regressed from intermediate hyperglycaemia to normoglycaemia compared with 268/738 (36%) participants in the placebo group. The incidence of T2DM after the 12-week off-treatment extension period (i.e. after 172 weeks) showed that five additional participants were diagnosed T2DM in the liraglutide group, compared with one participant in the placebo group. After 12-week treatment cessation, 740/1472 (50%) participants in the liraglutide group compared with 263/738 (36%) participants in the placebo group had normoglycaemia.One trial used exenatide and 2/17 participants randomised to exenatide versus 1/16 participants randomised to placebo developed T2DM (very low-quality evidence). This trial did not provide a definition of T2DM. One trial reported serious adverse events in 230/1524 (15.1%) participants in the liraglutide 3.0 mg arm versus 96/755 (12.7%) participants in the placebo arm (very low quality evidence). There were no serious adverse events in the trial using exenatide. Non-fatal myocardial infarction was reported in 1/1524 participants in the liraglutide arm and in 0/55 participants in the placebo arm at 172 weeks (very low-quality evidence). One trial reported congestive heart failure in 1/1524 participants in the liraglutide arm and in 1/755 participants in the placebo arm (very low-quality evidence). Participants receiving liraglutide compared with placebo had a small mean improvement in the physical component of the 36-item Short Form scale showing a difference of 0.87 points (95% CI 0.17 to 1.58; P = 0.02; 1 trial; 1791 participants; very low-quality evidence). No trial evaluating GLP-1-analogues reported data on stroke, microvascular complications or socioeconomic effects.

AUTHORS' CONCLUSIONS

There is no firm evidence that DPP-4 inhibitors or GLP-1 analogues compared mainly with placebo substantially influence the risk of T2DM and especially its associated complications in people at increased risk for the development of T2DM. Most trials did not investigate patient-important outcomes.

DPP-4 inhibition has no acute effect on BNP and its N-terminal pro-hormone measured by commercial immune-assays. A randomized cross-over trial in patients with type 2 diabetes

Background

Use of dipeptidyl peptidase-4 inhibitors (DPP4-i) for the treatment of type 2 diabetes (T2D) has been associated with a possible increase in the risk for heart failure (HF). B-type natriuretic peptide (BNP), which is both a biomarker of HF and a hemodynamically active hormone, is a substrate of DPP-4. We herein tested the acute effects of the DPP-4i linagliptin on BNP and NT-proBNP in a cross-over placebo-controlled trial in patients with T2D with and without chronic kidney disease (CKD).

Methods

B-type natriuretic peptide and NT-proBNP were measured using commercially available clinical-grade immune-assays at baseline and at the end of a 4-day treatment with placebo and linagliptin. Changes from baseline during each treatment arm, as well as placebo-subtracted effects of linagliptin on BNP and NT-proBNP were calculated.

Results

46 patients completed the study, 18 of whom were affected by CKD. Baseline BNP and NT-proBNP levels increased with age, were elevated in CKD patients, and inversely correlated with estimated glomerular filtration rate. No significant change was detected in BNP and NT-proBNP levels after treatment with linagliptin or placebo in patients with or without CKD. Only in CKD patients the placebo-subtracted effect of linagliptin indicated a significant reduction in NT-proBNP levels, but this finding was not statistically robust.

Conclusions

Acute treatment with a DPP-4i exerts no clinically-meaningful effects on BNP and NT-proBNP. As routinely used immunoassays do not discriminate between intact/active and cleaved BNP, these data cannot rule out an effect of DPP-4i on HF pathophysiology.

Trial registration NCT01617824