Combination therapy of metformin plus dipeptidyl peptidase-4 inhibitor versus metformin plus sulfonylurea and their association with a decreased risk of cardiovascular disease in type 2 diabetes mellitus patients

Cardiovascular safety of evogliptin dual and triple therapy in patients with type 2 diabetes: a nationwide cohort study

OBJECTIVE

To investigate the risk of cardiovascular events associated with commonly used dual and triple therapies of evogliptin, a recently introduced dipeptidyl peptidase-4 inhibitor (DPP4i), for managing type 2 diabetes in routine clinical practice.

DESIGN

A retrospective cohort study.

SETTING

Korean Health Insurance Review and Assessment database.

PARTICIPANTS

Patients who initiated metformin-based dual therapy and metformin+sulfonylurea-based triple therapy in South Korea from 2014 to 2018.

INTERVENTIONS

Initiation of combination therapy with evogliptin.

PRIMARY AND SECONDARY OUTCOME MEASURES

Hazards of cardiovascular events, a composite endpoint of myocardial infarction, heart failure and cerebrovascular events, and its individual components. Cox proportional hazards model with propensity score-based inverse probability of treatment weighting were used to estimate HRs and 95% CIs.

RESULTS

From the dual and triple therapy cohorts, 5830 metformin+evogliptin users and 2198 metformin+sulfonylurea+evogliptin users were identified, respectively. Metformin+evogliptin users, as compared with metformin+non-DPP4i, had a 29% reduced risk of cardiovascular events (HR 0.71, 95% CI 0.62 to 0.82); HRs for individual outcomes were cerebrovascular events (0.71, 95% CI 0.53 to 0.95), heart failure (0.70, 95% CI 0.59 to 0.82), myocardial infarction (0.89, 95% CI 0.60 to 1.31). Metformin+sulfonylurea+evogliptin users, compared with metformin+sulfonylurea+non-DPP4i, had a 24% reduced risk of cardiovascular events (0.76, 95% CI 0.59 to 0.97); HRs for individual outcomes were myocardial infarction (0.57, 95% CI 0.27 to 1.19), heart failure (0.74, 95% CI 0.55 to 1.01), cerebrovascular events (0.96, 95% CI 0.61 to 1.51).

CONCLUSIONS

These findings suggest that dual or triple therapies of evogliptin for the management of type 2 diabetes in routine clinical practice present no cardiovascular harms, but could alternatively offer cardiovascular benefits in this patient population.

Incident infection risks depending on oral antidiabetic exposure in insulin-treated type 2 diabetes patients

Dipeptidyl peptidase-4 inhibitors (DPP4is) and sodium glucose cotransporter-2 inhibitors (SGLT2is) have been speculated to have a potential to increase infection risks in type 2 diabetes mellitus (T2DM) patients. We performed a cohort study using the Korean health insurance data to investigate infection risks with each drug class relative to metformin in insulin-treated T2DM patients. After propensity score matching, we included 1,498 and 749 patients in DPP4i + insulin vs metformin + insulin and 300 and 549 patients in SGLT2i + insulin vs metformin + insulin, respectively. In stratified analyses per patient factor, none of the odds ratios (ORs) were associated with a statistical significance across respiratory, genital, and urinary tract infections (UTIs), except that of the male stratum for respiratory infections (OR 0.77, p = 0.04). With regard to SGLT2is, a higher risk of genital infections was analyzed with their use than with metformin therapy (OR 1.76, p = 0.03). In stratified analyses, the OR for genital infections remained significant in the baseline cardiovascular disease stratum (OR 2.29, p = 0.01). No increased UTI risk was detected with SGLT2is compared against metformin. In this study on insulin-receiving T2DM patients, DPP4is were not associated with increased infection risks, whereas SGLT2is led to a higher risk for genital infections, but not for UTIs, relative to metformin.

The Synergistic Action of Metformin and Glycyrrhiza uralensis Fischer Extract Alleviates Metabolic Disorders in Mice with Diet-Induced Obesity

Metformin, an antidiabetic drug, and Glycyrrhiza uralensis Fischer (GU), an oriental medicinal herb, have been reported to exert anti-obesity effects. This study investigated the synergistic action of metformin and GU in improving diet-induced obesity. Mice were fed a normal diet, a high-fat diet (HFD), or HFD + 0.015% GU water extract for 8 weeks. The HFD and GU groups were then randomly divided into two groups and fed the following diets for the next 8 weeks: HFD with 50 mg/kg metformin (HFDM) and GU with 50 mg/kg metformin (GUM). GUM prevented hepatic steatosis and adiposity by suppressing expression of mRNAs and enzyme activities related to lipogenesis in the liver and upregulating the expression of adipocyte mRNAs associated with fatty acid oxidation and lipolysis, and as a result, improved dyslipidemia. Moreover, GUM improved glucose homeostasis by inducing glucose uptake in tissues and upregulating mRNA expressions associated with glycolysis in the liver and muscle through AMP-activated protein kinase activation. GUM also improved inflammation by increasing antioxidant activity in the liver and erythrocytes and decreasing inflammatory cytokine productions. Here, we demonstrate that GU and metformin exert synergistic action in the prevention of obesity and its complications.

Therapeutic Effects of Switching to Anagliptin from Other DPP-4 Inhibitors in T2DM Patients with Inadequate Glycemic Control: A Non-interventional, Single-Arm, Open-Label, Multicenter Observational Study

INTRODUCTION

The effects of switching DPP-4 inhibitors in type 2 diabetes mellitus (T2DM) patients are being widely studied. However, information of which factors affect the therapeutic response is limited. We evaluated the difference in HbA1c lowering effect by comorbidity and other variables after switching to anagliptin in patients with T2DM inadequately controlled by other DPP-4 inhibitors.

METHODS

In a multicenter, open-label, single-arm, prospective observational study, patients with T2DM, HbA1c ≥ 7.0% who have taken DPP-4 inhibitors other than anagliptin, either alone or in combination (DPP-4 inhibitors + metformin/sulfonylurea (SU)/thiazolidinedione (TZD)/insulin), for at least 8 weeks were enrolled. After the switch to anagliptin, HbA1c and available clinical characteristics were determined.

RESULTS

The change in HbA1c levels from baseline to week 12 and 24 was - 0.40% and - 0.42% in all patients. However, comparing the subgroups without and with comorbidities, the change in HbA1c levels at weeks 12 and 24 was - 0.68% and - 0.89% vs. - 0.27% and 0.22%, respectively. In addition, the proportion of patients achieving HbA1c < 7% from baseline to week 12 and 24 was increased to 70% and 70% vs. 20% and 24%, respectively. Duration of T2DM and different subtype classes of DPP-4 inhibitor did not significantly contribute to the change in HbA1c.

CONCLUSION

In patients with T2DM poorly controlled by other DPP-4 inhibitors, HbA1c levels were significantly decreased after switching to anagliptin. Given that the change in HbA1c was greater in patients without comorbidities than in patients with comorbidities, switching to anagliptin before adding other oral hypoglycemic agents (OHAs) may be an option in patients without comorbidities.

[Cardiovascular preventive recommendations. PAPPS 2022 thematic updates. Working groups of the PAPPS]

The recommendations of the semFYC's Program for Preventive Activities and Health Promotion (PAPPS) for the prevention of cardiovascular diseases (CVD) are presented. The following sections are included: epidemiological review, where the current morbidity and mortality of CVD in Spain and its evolution as well as the main risk factors are described; cardiovascular (CV) risk and recommendations for the calculation of CV risk; main risk factors such as arterial hypertension, dyslipidemia and diabetes mellitus, describing the method for their diagnosis, therapeutic objectives and recommendations for lifestyle measures and pharmacological treatment; indications for antiplatelet therapy, and recommendations for screening of atrial fibrillation, and recommendations for management of chronic conditions. The quality of testing and the strength of the recommendation are included in the main recommendations.

Cardiovascular Effects of Incretin-Based Therapies: Integrating Mechanisms With Cardiovascular Outcome Trials

As the worldwide prevalence of diabetes and obesity continues to rise, so does the risk of debilitating cardiovascular complications. Given the significant association between diabetes and cardiovascular risk, the actions of glucose-lowering therapies within the cardiovascular system must be clearly defined. Incretin hormones, including GLP-1 (glucagon-like peptide 1) and GIP (glucose-dependent insulinotropic polypeptide), are gut hormones secreted in response to nutrient intake that maintain glycemic control by regulating insulin and glucagon release. GLP-1 receptor agonists (GLP-1Ras) and dipeptidyl peptidase 4 inhibitors (DPP-4is) represent two drug classes used for the treatment of type 2 diabetes mellitus (T2DM) that improve glucose regulation through stimulating the actions of gut-derived incretin hormones or inhibiting their degradation, respectively. Despite both classes acting to potentiate the incretin response, the potential cardioprotective benefits afforded by GLP-1Ras have not been recapitulated in cardiovascular outcome trials (CVOTs) evaluating DPP-4is. This review provides insights through discussion of clinical and preclinical studies to illuminate the physiological mechanisms that may underlie and reconcile observations from GLP-1Ra and DPP-4i CVOTs. Furthermore, critical knowledge gaps and areas for further investigation will be emphasized to guide future studies and, ultimately, facilitate improved clinical management of cardiovascular disease in T2DM.

SARS-CoV-2 and diabetes: A potential therapeutic effect of dipeptidyl peptidase 4 inhibitors in diabetic patients diagnosed with COVID-19

COVID-19 is caused by severe acute respiratory syndrome coronavirus 2 and has become an urgent economic and health challenge. Dipeptidyl peptidase 4 (DPP4), also mentioned as a cluster of differentiation 26 (CD26) is a serine exopeptidase found in two arrangements: a soluble form (sDPP-4) and a plasma membrane-bound form. Because other coronaviruses enter the cells by binding to DPP-4, it has been speculated that DPP-4 inhibitors may exert activity against COVID-19. Therefore, this review aimed to summarize the potential therapeutic effect of dipeptidyl peptidase 4 inhibitors in diabetic patients diagnosed with COVID-19. To include different studies, publications related to Dipeptidyl peptidase-4 inhibitor use and clinical outcomes from COVID-19 were searched from the databases such as Web of Science, PubMed, Medline, Elsevier, Google Scholar, and SCOPUS, via English key terms. A direct engrossment of DPP4 in COVID-19 needs to be elucidated, there is also evidence confirming that DPP4 inhibitors exert anti-fibrotic and modulate inflammation activity. Thus, the use of DPP-4 inhibitors could reduce mortality due to COVID-19 or improve the progression of COVID-19; this evidence may support the management of diabetic patients diagnosed with COVID-19; however more well-designed investigation is urgently required.

Cardiovascular safety of evogliptin in patients with type 2 diabetes: A nationwide cohort study

AIM

To assess whether the use of evogliptin, a novel dipeptidyl peptidase-4 inhibitor (DPP-4i), was associated with an increased risk of cardiovascular events compared with glimepiride in patients with type 2 diabetes (T2D).

METHODS

We conducted a population-based cohort study using South Korea's nationwide healthcare database from 1 January 2014 to 31 December 2018. We identified a base cohort of patients with T2D who newly initiated metformin monotherapy, from which we identified a study cohort of patients who either added or switched to glimepiride or DPP-4is (including evogliptin). Patients were followed up from initiation of DPP-4is or glimepiride until the earliest of either outcome occurrence or 31 December 2018. Our primary outcome was hospitalization or an emergency visit for cardiovascular events, a composite endpoint comprised of cerebrovascular events, heart failure, myocardial infarction, transient ischaemic attack, angina pectoris and revascularization procedures; secondary outcomes were the individual components of the primary outcome. A multivariable Cox proportional hazards model was used to estimate adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs) for the risk of study outcomes associated with evogliptin compared with glimepiride.

RESULTS

Our base and study cohorts had 317,307 and 128,788 patients, respectively, of which 100,038 were DPP-4i users (2946 were evogliptin users) and 28,750 were glimepiride users within the study cohort. The median follow-up was 195 days for evogliptin and 113 days for glimepiride users. Compared with glimepiride, evogliptin was associated with a reduced risk of the primary outcome (aHR 0.67, 95% CI 0.48-0.95) and cerebrovascular events (aHR 0.41, 95% CI 0.22-0.78) but showed non-significant associations for myocardial infarction (aHR 0.63, 95% CI 0.27-1.46), heart failure (aHR 0.35, 95% CI 0.09-1.47), transient ischaemic attack (aHR 0.23, 95% CI 0.03-1.72) and angina pectoris (aHR 1.35, 95% CI 0.82-2.21).

CONCLUSIONS

Findings from this population-based cohort study provide novel real-world evidence that the use of evogliptin, compared with glimepiride, did not increase the risk of cardiovascular events, including cerebrovascular events, myocardial infarction, heart failure, transient ischaemic attack and angina pectoris.

Cardiovascular Outcomes Comparison of Dipeptidyl Peptidase-4 Inhibitors versus Sulfonylurea as Add-on Therapy for Type 2 Diabetes Mellitus: a Meta-Analysis

Objective

Recent studies have raised concern about the cardiovascular safety of dipeptidyl peptidase-4 (DPP4) inhibitors. We performed a systematic review through meta-analysis to compare cardiovascular outcomes of sulfonylurea (SU) versus DPP4 inhibitors when used in combination with metformin.

Methods

After searching for trials using combination therapy of metformin with DPP4 inhibitor or SU in PubMed, Cochrane Library, and Embase, one prospective observation study and 15 randomized controlled studies were selected.

Results

Regarding the primary analysis endpoint, there were no significant differences in the risk of all-cause mortality between SU and DPP4 inhibitors as an add-on therapy to metformin (random-effect relative risk [RR], 1.14; 95% confidence interval [CI], 0.98–1.33; p=0.811; I²=0%). Cardiovascular death was also similar between the two drug classes in the five studies which reported outcomes (random-effect RR, 1.03; 95% CI, 0.83–1.27; p=0.517; I²=0%). Furthermore, there were no significant differences in major adverse cardiac events (MACE), coronary heart disease, myocardial infarction, ischemic stroke and heart failure. However, there were less hypoglycemic events and weight gain in the DPP4 inhibitor group as compared with the SU group (random-effect RR, 3.79; 95% CI, 1.53–9.39; p<0.001; I²=98.2 and weighted mean difference, 1.68; 95% CI, 1.07–2.29; p<0.001; I²=94.7, respectively).

Conclusion

As add-on therapy to metformin, there were no significant differences in all-cause mortality and cardiovascular mortality between DPP4 inhibitors and SUs.

[Cardiovascular preventive recommendations. PAPPS 2020 update]

The recommendations of the semFYC's Program for Preventive Activities and Health Promotion (PAPPS) for the prevention of cardiovascular diseases (CVD) are presented. The following sections are included: Epidemiological review, where the current morbidity and mortality of CVD in Spain and its evolution as well as the main risk factors are described; Cardiovascular (CV) risk tables and recommendations for the calculation of CV risk; Main risk factors such as arterial hypertension, dyslipidemia and diabetes mellitus, describing the method for their diagnosis, therapeutic objectives and recommendations for lifestyle measures and pharmacological treatment; Indications for antiplatelet therapy, and recommendations for screening of atrial fibrillation. The quality of testing and the strength of the recommendation are included in the main recommendations.

DPP4 and ACE2 in Diabetes and COVID-19: Therapeutic Targets for Cardiovascular Complications?

COVID-19 outbreak, caused by severe acute respiratory syndrome (SARS)-CoV-2 coronavirus has become an urgent health and economic challenge. Diabetes is a risk factor for severity and mortality of COVID-19. Recent studies support that COVID-19 has effects beyond the respiratory tract, with vascular complications arising as relevant factors worsening its prognosis, then making patients with previous vascular disease more prone to severity or fatal outcome. Angiotensin-II converting enzime-2 (ACE2) has been proposed as preferred receptor for SARS-CoV-2 host infection, yet specific proteins participating in the virus entry are not fully known. SARS-CoV-2 might use other co-receptor or auxiliary proteins allowing virus infection. In silico experiments proposed that SARS-CoV-2 might bind dipeptidyl peptidase 4 (DPP4/CD26), which was established previously as receptor for MERS-CoV. The renin-angiotensin-aldosterone system (RAAS) component ACE2 and DPP4 are proteins dysregulated in diabetes. Imbalance of the RAAS and direct effect of soluble DPP4 exert deleterious vascular effects. We hypothesize that diabetic patients might be more affected by COVID-19 due to increased presence ACE2 and DPP4 mediating infection and contributing to a compromised vasculature. Here, we discuss the role of ACE2 and DPP4 as relevant factors linking the risk of SARS-CoV-2 infection and severity of COVID-19 in diabetic patients and present an outlook on therapeutic potential of current drugs targeted against RAAS and DPP4 to treat or prevent COVID-19-derived vascular complications. Diabetes affects more than 400 million people worldwide, thus better understanding of how they are affected by COVID-19 holds an important benefit to fight against this disease with pandemic proportions.

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.

Are the cardiovascular and kidney benefits of empagliflozin influenced by baseline glucose-lowering therapy?

AIMS

In the EMPA-REG OUTCOME® trial, the sodium-glucose cotransporter 2 inhibitor empagliflozin when given in addition to standard care improved cardiovascular (CV) and renal outcomes, and reduced mortality. Trial participants were on a variety of glucose-lowering therapies at baseline, some of which could potentially affect CV risk. This analysis investigated whether the use of background diabetes therapy affected the risk of CV death, hospitalizations for heart failure, and progression of chronic kidney disease, among patients treated with empagliflozin.

MATERIALS AND METHODS

Patients meeting inclusion and exclusion criteria were randomized to placebo, empagliflozin 10 mg or empagliflozin 25 mg; glucose-lowering therapy was to remain unchanged for 12 weeks and then adjusted to achieve glycaemic control according to local guidelines. Differences in risk of cardio-renal outcomes between empagliflozin and placebo by baseline use of metformin, sulphonylurea (SU) and insulin were assessed using a Cox proportional hazards model.

RESULTS

Of 7020 eligible patients, 74% were receiving metformin, 43% SU and 48% insulin at baseline (each alone or in combination); the most common regimens were metformin plus SU (20%) and metformin plus insulin (20%). Empagliflozin reduced the risk of CV death irrespective of the use of: metformin [with: hazard ratio (HR) 0.71 (95% confidence interval, CI, 0.54-0.94); without: 0.46 (0.32-0.68); P_interaction = 0.07]; SU [with: HR 0.64 (0.44-0.92); without: 0.61 (0.46-0.81); P_interaction = 0.85]; or insulin [with: HR 0.63 (0.46-0.85); without: 0.61 (0.44-0.85); P_interaction = 0.92]. Reductions in three-point major adverse CV events, hospitalizations for heart failure, and all-cause mortality were consistent across subgroups of baseline therapies. Empagliflozin reduced the risks of incident or worsening nephropathy versus placebo irrespective of the use of SU or insulin at baseline (P_interaction > 0.05), but there was a greater reduction in this risk for patients not using metformin [HR 0.47 (95% CI 0.37-0.59)] versus those using metformin [HR 0.68 (95% CI 0.58-0.79)] at baseline (P_interaction = 0.01).

CONCLUSIONS

The addition of empagliflozin to antihyperglycaemic regimens of patients with type 2 diabetes and CV disease consistently reduced their risks of adverse CV outcomes and mortality irrespective of baseline use of metformin, SU or insulin. For chronic kidney disease progression, there may be a larger benefit from empagliflozin in those patients who are not using metformin.

Toxicity of Metformin and Hypoglycemic Therapies

Metformin along with other antidiabetic medications provide benefit to patients in the treatment of type 2 diabetes mellitus, but caution is advised in certain scenarios to avoid toxicity in kidney disease. Renal dosing, monitoring of kidney function, and evaluating the risk of developing serious side effects are warranted with some agents. The available literature with regard to incidence of adverse events and toxicity of hypoglycemic therapies is reviewed.

Effect of metformin on all-cause and cardiovascular mortality in patients with coronary artery diseases: a systematic review and an updated meta-analysis

BACKGROUND

Metformin is the most widely prescribed drug to lower glucose and has a definitive effect on the cardiovascular system. The goal of this systematic review and meta-analysis is to assess the effects of metformin on mortality and cardiac function among patients with coronary artery disease (CAD).

METHODS

Relevant studies reported before October 2018 was retrieved from databases including PubMed, EMBASE, Cochrane Library and Web of Science. Hazard ratio (HR) was calculated to evaluate the all-cause mortality, cardiovascular mortality and incidence of cardiovascular events (CV events), to figure out the level of left ventricular ejection fraction (LVEF), creatine kinase MB (CK-MB), type B natriuretic peptide (BNP) and to compare the average level of low density lipoprotein (LDL).

RESULTS

In this meta-analysis were included 40 studies comprising 1,066,408 patients. The cardiovascular mortality, all-cause mortality and incidence of CV events were lowered to adjusted HR (aHR) = 0.81, aHR = 0.67 and aHR = 0. 83 respectively after the patients with CAD were given metformin. Subgroup analysis showed that metformin reduced all-cause mortality in myocardial infarction (MI) (aHR = 0.79) and heart failure (HF) patients (aHR = 0.84), the incidence of CV events in HF (aHR = 0.83) and type II diabetes mellitus (T2DM) patients (aHR = 0.83), but had no significant effect on MI (aHR = 0.87) and non-T2DM patients (aHR = 0.92). Metformin is superior to sulphonylurea (aHR = 0.81) in effects on lowering the incidence of CV events and in effects on patients who don't use medication. The CK-MB level in the metformin group was lower than that in the control group standard mean difference (SMD) = - 0.11). There was no significant evidence that metformin altered LVEF (MD = 2.91), BNP (MD = - 0.02) and LDL (MD = - 0.08).

CONCLUSION

Metformin reduces cardiovascular mortality, all-cause mortality and CV events in CAD patients. For MI patients and CAD patients without T2DM, metformin has no significant effect of reducing the incidence of CV events. Metformin has a better effect of reducing the incidence of CV events than sulfonylureas.

Metformin and second- or third-generation sulphonylurea combination therapy for adults with type 2 diabetes mellitus

BACKGROUND

The number of people with type 2 diabetes mellitus (T2DM) is increasing worldwide. The combination of metformin and sulphonylurea (M+S) is a widely used treatment. Whether M+S shows better or worse effects in comparison with other antidiabetic medications for people with T2DM is still controversial.

OBJECTIVES

To assess the effects of metformin and sulphonylurea (second- or third-generation) combination therapy for adults with type 2 diabetes mellitus.

SEARCH METHODS

We updated the search of a recent systematic review from the Agency for Healthcare Research and Quality (AHRQ). The updated search included CENTRAL, MEDLINE, Embase, ClinicalTrials.gov and WHO ICTRP. The date of the last search was March 2018. We searched manufacturers' websites and reference lists of included trials, systematic reviews, meta-analyses and health technology assessment reports. We asked investigators of the included trials for information about additional trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) randomising participants 18 years old or more with T2DM to M+S compared with metformin plus another glucose-lowering intervention or metformin monotherapy with a treatment duration of 52 weeks or more.

DATA COLLECTION AND ANALYSIS

Two review authors read all abstracts and full-text articles and records, assessed risk of bias and extracted outcome data independently. We used a random-effects model to perform meta-analysis, and calculated risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes, using 95% confidence intervals (CIs) for effect estimates. We assessed the certainty of the evidence using the GRADE instrument.

MAIN RESULTS

We included 32 RCTs randomising 28,746 people. Treatment duration ranged between one to four years. We judged none of these trials as low risk of bias for all 'Risk of bias' domains. Most important events per person were all-cause and cardiovascular mortality, serious adverse events (SAE), non-fatal stroke (NFS), non-fatal myocardial infarction (MI) and microvascular complications. Most important comparisons were as follows:Five trials compared M+S (N = 1194) with metformin plus a glucagon-like peptide 1 analogue (N = 1675): all-cause mortality was 11/1057 (1%) versus 11/1537 (0.7%), risk ratio (RR) 1.15 (95% confidence interval (CI) 0.49 to 2.67); 3 trials; 2594 participants; low-certainty evidence; cardiovascular mortality 1/307 (0.3%) versus 1/302 (0.3%), low-certainty evidence; serious adverse events (SAE) 128/1057 (12.1%) versus 194/1537 (12.6%), RR 0.90 (95% CI 0.73 to 1.11); 3 trials; 2594 participants; very low-certainty evidence; non-fatal myocardial infarction (MI) 2/549 (0.4%) versus 6/1026 (0.6%), RR 0.57 (95% CI 0.12 to 2.82); 2 trials; 1575 participants; very low-certainty evidence.Nine trials compared M+S (N = 5414) with metformin plus a dipeptidyl-peptidase 4 inhibitor (N = 6346): all-cause mortality was 33/5387 (0.6%) versus 26/6307 (0.4%), RR 1.32 (95% CI 0.76 to 2.28); 9 trials; 11,694 participants; low-certainty evidence; cardiovascular mortality 11/2989 (0.4%) versus 9/3885 (0.2%), RR 1.54 (95% CI 0.63 to 3.79); 6 trials; 6874 participants; low-certainty evidence; SAE 735/5387 (13.6%) versus 779/6307 (12.4%), RR 1.07 (95% CI 0.97 to 1.18); 9 trials; 11,694 participants; very low-certainty evidence; NFS 14/2098 (0.7%) versus 8/2995 (0.3%), RR 2.21 (95% CI 0.74 to 6.58); 4 trials; 5093 participants; very low-certainty evidence; non-fatal MI 15/2989 (0.5%) versus 13/3885 (0.3%), RR 1.45 (95% CI 0.69 to 3.07); 6 trials; 6874 participants; very low-certainty evidence; one trial in 64 participants reported no microvascular complications were observed (very low-certainty evidence).Eleven trials compared M+S (N = 3626) with metformin plus a thiazolidinedione (N = 3685): all-cause mortality was 123/3300 (3.7%) versus 114/3354 (3.4%), RR 1.09 (95% CI 0.85 to 1.40); 6 trials; 6654 participants; low-certainty evidence; cardiovascular mortality 37/2946 (1.3%) versus 41/2994 (1.4%), RR 0.78 (95% CI 0.36 to 1.67); 4 trials; 5940 participants; low-certainty evidence; SAE 666/3300 (20.2%) versus 671/3354 (20%), RR 1.01 (95% CI 0.93 to 1.11); 6 trials; 6654 participants; very low-certainty evidence; NFS 20/1540 (1.3%) versus 16/1583 (1%), RR 1.29 (95% CI 0.67 to 2.47); P = 0.45; 2 trials; 3123 participants; very low-certainty evidence; non-fatal MI 25/1841 (1.4%) versus 21/1877 (1.1%), RR 1.21 (95% CI 0.68 to 2.14); P = 0.51; 3 trials; 3718 participants; very low-certainty evidence; three trials (3123 participants) reported no microvascular complications (very low-certainty evidence).Three trials compared M+S (N = 462) with metformin plus a glinide (N = 476): one person died in each intervention group (3 trials; 874 participants; low-certainty evidence); no cardiovascular mortality (2 trials; 446 participants; low-certainty evidence); SAE 34/424 (8%) versus 27/450 (6%), RR 1.68 (95% CI 0.54 to 5.21); P = 0.37; 3 trials; 874 participants; low-certainty evidence; no NFS (1 trial; 233 participants; very low-certainty evidence); non-fatal MI 2/215 (0.9%) participants in the M+S group; 2 trials; 446 participants; low-certainty evidence; no microvascular complications (1 trial; 233 participants; low-certainty evidence).Four trials compared M+S (N = 2109) with metformin plus a sodium-glucose co-transporter 2 inhibitor (N = 3032): all-cause mortality was 13/2107 (0.6%) versus 19/3027 (0.6%), RR 0.96 (95% CI 0.44 to 2.09); 4 trials; 5134 participants; very low-certainty evidence; cardiovascular mortality 4/1327 (0.3%) versus 6/2262 (0.3%), RR 1.22 (95% CI 0.33 to 4.41); 3 trials; 3589 participants; very low-certainty evidence; SAE 315/2107 (15.5%) versus 375/3027 (12.4%), RR 1.02 (95% CI 0.76 to 1.37); 4 trials; 5134 participants; very low-certainty evidence; NFS 3/919 (0.3%) versus 7/1856 (0.4%), RR 0.87 (95% CI 0.22 to 3.34); 2 trials; 2775 participants; very low-certainty evidence; non-fatal MI 7/890 (0.8%) versus 8/1374 (0.6%), RR 1.43 (95% CI 0.49 to 4.18; 2 trials); 2264 participants; very low-certainty evidence; amputation of lower extremity 1/437 (0.2%) versus 1/888 (0.1%); very low-certainty evidence.Trials reported more hypoglycaemic episodes with M+S combination compared to all other metformin-antidiabetic agent combinations. Results for M+S versus metformin monotherapy were inconclusive. There were no RCTs comparing M+S with metformin plus insulin. We identified nine ongoing trials and two trials are awaiting assessment. Together these trials will include approximately 16,631 participants.

AUTHORS' CONCLUSIONS

There is inconclusive evidence whether M+S combination therapy compared with metformin plus another glucose-lowering intervention results in benefit or harm for most patient-important outcomes (mortality, SAEs, macrovascular and microvascular complications) with the exception of hypoglycaemia (more harm for M+S combination). No RCT reported on health-related quality of life.

Impact of metformin use on the cardiovascular effects of dipeptidyl peptidase-4 inhibitors: An analysis of Medicare claims data from 2007 to 2015

AIMS

To examine the outcomes of dipeptidyl peptidase-4 (DPP-4) inhibitor initiation with and without concurrent metformin treatment.

MATERIALS AND METHODS

We identified Medicare enrollees initiating a DPP-4 inhibitor, a sulphonylurea or a thiazolidinedione. Using propensity-score-weighted Poisson models, we evaluated 1-year cardiovascular (CV) outcome incidence among initiators of DPP-4 inhibitors versus comparators in subgroups with and without concurrent metformin use, and assessed the interaction between initiation drug and metformin. Outcomes included mortality, non-fatal myocardial infarction (MI), stroke, and a composite outcome.

RESULTS

For the DPP-4 inhibitor (n = 13 391) versus sulphonylurea (n = 33 206) comparison, rate differences in composite outcome incidence favoured DPP-4 inhibitors: -2.0/100 person-years among metformin users (95% confidence interval [CI] -2.7 to -1.3) and - 1.0/100 person-years (95% CI -1.8 to -0.2) among metformin non-users. Similar rate difference trends among metformin users and non-users were seen for mortality (-1.5/100 person-years [95% CI -2.1 to -0.9] and -0.7/100 person-years [95% CI -1.4 to 0.0]) and non-fatal MI (-0.5/100 person-years [95% CI -0.8, -0.3] and 0.1/100 person-years [95% CI -0.2 to 0.4]). The interaction between DPP-4 inhibitor initiation and metformin was statistically significant for non-fatal MI (P = 0.008). For the DPP-4 inhibitor (n = 22 210) versus thiazolidinedione (n = 9517) comparison, rate differences in composite outcome incidence for DPP-4 inhibitor initiation were -0.6/100 person-years (95% CI -1.5 to 0.2) among metformin users and 1.0 (95% CI 0.0 to 2.0) among metformin non-users. Similar rate difference trends among metformin users and non-users were seen for mortality (-0.5/100 person-years [95% CI -1.3 to 0.1] and 0.8/100 person-years [95% CI -0.0 to 1.7]) and non-fatal MI (-0.1/100 person-years [95% CI -0.4 to 0.2] and 0.2/100 person-years [95% CI -0.1 to 0.6]). The interaction between DPP-4 inhibitor initiation and metformin was statistically significant for the composite outcome (P = 0.024) and mortality (P = 0.023).

CONCLUSION

Incidence rate differences in multiple CV outcomes appeared more favourable when DPP-4 inhibitor initiation occurred in the presence of metformin, suggesting a possible interaction between DPP-4 inhibitors and metformin.

The Effect of Linagliptin versus Metformin Treatment-Related Quality of Life in Patients with Type 2 Diabetes Mellitus

INTRODUCTION

There have been no studies directly comparing the effect of dipeptidyl peptidase-4 inhibitors with that of metformin on treatment-related quality of life (QOL) when used as first-line therapy in patients with type 2 diabetes mellitus (T2DM).

METHODS

This study is a prospective, randomized, open-label, multicenter, parallel-group, comparative study. Forty-four participants who failed to achieve target glycemic control with diet and exercise therapy were randomly allocated to receive linagliptin or metformin therapy. We compared treatment-related QOL among the two groups using the Oral Hypoglycemic Agent Questionnaire, version 2 (OHA-Q version 2) and the self-administered Diabetes Therapy-Related QOL (DTR-QOL) questionnaire.

RESULTS

After randomization, 21 patients in the linagliptin group and 22 patients in the metformin treatment group were included in the full analysis set. Biochemical parameters, incidence of adverse effects, and rate of adherence to medication were comparable between the two groups. Over the 24-week treatment period, no significant differences in overall OHA-Q scores between the groups were observed, although the subscale 1 (treatment convenience) score was significantly higher in the linagliptin group than in the metformin group. The overall DTR-QOL score did not differ between the two groups; however, the DTR-QOL scores significantly improved after 24 weeks of linagliptin treatment, but not after metformin treatment.

CONCLUSION

We did not find significantly better treatment-related QOL with linagliptin among Japanese patients with T2DM. In terms of treatment convenience, our data showed that linagliptin was superior to metformin.

FUNDING

This study was financially supported by Nippon Boehringer Ingelheim Co., Ltd. and Eli Lilly and Company. The journal's article processing fees were covered by a research fund from Juntendo University.

CLINICAL TRIAL REGISTRATION

UMIN000022953.

Predictors of the Efficacy of Dipeptidyl Peptidase-4 Inhibitors in Taiwanese Patients with Type 2 Diabetes Mellitus

BACKGROUND/PURPOSE

Dipeptidyl peptidase-4 (DPP-4) inhibitors are the most popular oral antidiabetic drugs (OADs) in recent 20 years because of the low risk of hypoglycemia, intermediate efficacy to lower glycated hemoglobin (△HbA1c): 0.5-0.9%, neutral effect on body weight change, convenience for usage (mostly once daily), and rare occurrence of major side effects. The purpose of this study was to determine the important predictors of the efficacy of naïve use of DPP-4 inhibitors in Taiwanese patients with type 2 diabetes mellitus (T2D).

METHODS

A retrospective observational study was conducted. Of the T2D patients, 193 (122 men) naïve DPP-4 inhibitor users with an age of 58.0 ± 12.6 years, disease duration 5.4 ± 4.7 years, body mass index (BMI) 26.1 ± 4.3 kg/m², and estimated glomerular filtration rate 95.9 ± 27.0 mL/min/1.73M² were assessed for △HbA1c in 6 months.

RESULTS

After 6 months of DPP-4 inhibitors use, mostly second or third line of OADs (2.8 ± 0.7 kinds of OADs), 193 T2D patients (mean baseline HbA1c: 8.4 ± 1.4%) had △HbA1c 1.1 ± 1.2% on average (P < 0.01). The group with a higher baseline HbA1c level had more effective efficacy (△HbA1c ≥0.5%) in lowering HbA1c. Single regression analysis showed that the change in HbA1c after 6 months of treatment was positively associated with the baseline HbA1c level (R = 0.71, P < 0.001). In addition, multiple regression analysis showed that contributors to decrease HbA1c level after 6 months were high baseline HbA1c level, low BMI, short T2D duration, and fewer kinds of OADs.

CONCLUSION

Our study suggested that high baseline HbA1c level, low BMI, short T2D duration, and fewer kinds of OADs are the predictors of the efficacy of DPP-4 inhibitors in Taiwanese patients with T2D. The baseline HbA1c level, in particular, played the most important role in effective efficacy (△HbA1c ≥0.5%).

Do sulphonylureas still have a place in clinical practice?

Sulphonylureas have been commercially available since the 1950s, but their use continues to be associated with controversy. Although adverse cardiovascular outcomes in some observational studies have raised concerns about sulphonylureas, findings from relatively recent, robust, and high-quality systematic reviews have indicated no increased risk of all-cause mortality associated with sulphonylureas compared with other active treatments. Results from large, multicentre, randomised controlled trials such as the UK Prospective Diabetes Study and ADVANCE have confirmed the microvascular benefits of sulphonylureas, a reduction in the incidence or worsening of nephropathy and retinopathy, and no increase in all-cause mortality, although whether these benefits were due to sulphonylurea therapy and not an overall glucose-lowering effect could not be confirmed. A comparison of sulphonylureas and pioglitazone in the TOSCA.IT trial also confirmed the efficacy and cardiovascular safety of sulphonylureas. Investigators of randomised controlled trials have reported an increased risk of hypoglycaemia and weight gain with sulphonylureas, but data from observational studies suggest that the incidence of severe hypoglycaemia is lower in people taking sulphonylurea than in people taking insulin, and weight gain with sulphonylureas has been relatively modest in large cohort studies. 80% of people with diabetes live in low-to-middle income countries, so the effectiveness, affordability, and safety of sulphonylureas are particularly important considerations when prescribing glucose-lowering therapy. Results of ongoing head-to-head studies with new drugs, such as the comparison of glimepiride with linagliptin in the CAROLINA study and the comparison of various therapies (including sulphonylureas) for glycaemic control in the GRADE study, will determine the place of sulphonylureas in glucose-lowering therapy algorithms for patients with type 2 diabetes.

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.

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.

Circulating MicroRNAs in Elderly Type 2 Diabetic Patients

The circulating microRNAs (miRNAs) associated with type 2 diabetes (T2D) in elderly patients are still being defined. To identify novel miRNA biomarker candidates for monitoring responses to sitagliptin in such patients, we prospectively studied 40 T2D patients (age > 65) with HbA1c levels of 7.5-9.0% on metformin. After collection of baseline blood samples (t₀), the dipeptidyl peptidase-IV (DPP-IV) inhibitor (DPP-IVi) sitagliptin was added to the metformin regimen, and patients were followed for 15 months. Patients with HbA1c < 7.5% or HbA1c reduction > 0.5% after 3 and 15 months of therapy were classified as "responders" (group R, n = 34); all others were classified as "nonresponders" (group NR, n = 6). Circulating miRNA profiling was performed on plasma collected in each group before and after 15 months of therapy (t₀ and t₁₅). Intra- and intergroup comparison of miRNA profiles pinpointed three miRNAs that correlated with responses to sitagliptin: miR-378, which is a candidate biomarker of resistance to this DPP-IVi, and miR-126-3p and miR-223, which are associated with positive responses to the drug. The translational implications are as immediate as evident, with the possibility to develop noninvasive diagnostic tools to predict drug response and development of chronic complications.