All-cause mortality and cardiovascular effects associated with the DPP-IV inhibitor sitagliptin compared with metformin, a retrospective cohort study on the Danish population

Effect of metformin on adverse outcomes in T2DM patients: Systemic review and meta-analysis of observational studies

Background

The cardiovascular protection effect of metformin on patients with type 2 diabetes mellitus (T2DM) remains inconclusive. This systemic review and meta-analysis were to estimate the effect of metformin on mortality and cardiovascular events among patients with T2DM.

Methods

A search of the Pubmed and EMBASE databases up to December 2021 was performed. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were pooled by a random-effects model with an inverse variance method.

Results

A total of 39 studies involving 2473009 T2DM patients were adopted. Compared to non-metformin therapy, the use of metformin was not significantly associated with a reduced risk of major adverse cardiovascular event (MACE) (HR = 1.06, 95%CI 0.91–1.22; I² = 82%), hospitalization (HR = 0.85, 95%CI 0.64–1.13; I² = 98%), heart failure (HR = 0.86, 95%CI 0.60–1.25; I² = 99%), stroke (HR = 1.16, 95%CI 0.88–1.53; I² = 84%), and risk of AMI (HR = 0.88, 95%CI 0.69–1.14; I² = 88%) in T2DM patients. Metformin was also not associated with significantly lowered risk of MACE compared to dipeptidyl peptidase-4 inhibitor (DPP-4i) in T2DM patients (HR = 0.95, 95%CI 0.73–1.23; I² = 84%).

Conclusions

The effect of metformin on some cardiovascular outcomes was not significantly better than the non-metformin therapy or DPP-4i in T2DM patients based on observational studies.

A Clinical Perspective of the Multifaceted Mechanism of Metformin in Diabetes, Infections, Cognitive Dysfunction, and Cancer

In type 2 diabetes, ecological and lifecourse factors may interact with the host microbiota to influence expression of his/her genomes causing perturbation of interconnecting biological pathways with diverse clinical course. Metformin is a plant-based or plant-derived medicinal product used for the treatment of type 2 diabetes for over 60 years and is an essential drug listed by the World Health Organization. By reducing mitochondrial oxidative phosphorylation and adenosine triphosphate (ATP) production, metformin increased AMP (adenosine monophosphate)-activated protein kinase (AMPK) activity and altered cellular redox state with reduced glucagon activity, endogenous glucose production, lipogenesis, and protein synthesis. Metformin modulated immune response by directly reducing neutrophil to lymphocyte ratio and improving the phagocytic function of immune cells. By increasing the relative abundance of mucin-producing and short-chain-fatty-acid-producing gut microbes, metformin further improved the host inflammatory and metabolic milieu. Experimentally, metformin promoted apoptosis and reduced proliferation of cancer cells by reducing their oxygen consumption and modulating the microenvironment. Both clinical and mechanistic studies support the pluripotent effects of metformin on reducing cardiovascular–renal events, infection, cancer, cognitive dysfunction, and all-cause death in type 2 diabetes, making this low-cost medication a fundamental therapy for individualization of other glucose-lowering drugs in type 2 diabetes. Further research into the effects of metformin on cognitive function, infection and cancer, especially in people without diabetes, will provide new insights into the therapeutic value of metformin in our pursuit of prevention and treatment of ageing-related as well as acute and chronic diseases beyond diabetes.

Cardiovascular events and mortality among type 2 diabetes mellitus patients newly prescribed first-line blood glucose-lowering drugs monotherapies: A population-based cohort study in the Catalan electronic medical record database, SIDIAP, 2010-2015

AIM

To assess cardiovascular (CV) events and all-cause mortality in type 2 diabetes mellitus (T2DM) patients treated with first-line monotherapies of non-insulin antidiabetic drugs (NIADs).

METHODS

Longitudinal retrospective cohort study in the Catalan database SIDIAP (Information System for the Development of Research in Primary Care). T2DM patients ≥18 years newly prescribed first-line monotherapies during 2010-2015 were followed since their first prescription until the composite of major adverse CV events, MACE (myocardium infarction [MI], stroke and all-cause death), its components, heart failure (HF) and peripheral artery disease (PAD) or censoring. Cox proportional hazard models were used to estimate hazard ratios 95% confidence interval (HR [95%CI]).

RESULTS

Compared with metformin, the use of sulfonylureas, dipeptidyl peptidase-4 inhibitors (DPP-4 i) and meglitinides were significantly associated with higher risk for MACE (1.55 [1.42-1.68]); 1.49 [1.22-1.84] and 2.01 [1.29-3.12]) and all-cause mortality (1.67 [1.52-1.84], 1.65 [1.30-2.] and 2.08 [1.26-3.42]). Sulfonylureas users had increased risk of MI (1.38 [1.03-1.85]) stroke (1.31 [1.11-1.54]), HF (1.49 [1.28-1.72]) and PAD (1.24 [1.02-1.51]). Meglitinides users were at increased risks of MI, HR 2.03 (1.10-3.74).

CONCLUSION

In first-line monotherapies, compared with metformin, sulfonylureas were associated with increased risks in all the outcomes; DPP-4 i and repaglinide showed increased risks of MACE and mortality. Residual confounding cannot be ruled out.

A prospective cohort study on effects of gemigliptin on cardiovascular outcomes in patients with type 2 diabetes (OPTIMUS study)

This study was performed to evaluate the long-term cardiovascular safety of gemigliptin in patients with type 2 diabetes mellitus (T2DM). After screening, eligible patients with T2DM were enrolled, received gemigliptin, and were followed up for a median of 2.50 years. The primary outcome was a composite of confirmed cardiovascular death, nonfatal myocardial infarction, or nonfatal ischemic stroke (3-point major adverse cardiovascular event [MACE]). The key secondary outcomes were incidence of all-cause mortality and any other cardiovascular events. A total of 5179 patients were included in the study and 5113 were treated with gemigliptin. Overall, the primary outcome occurred in 26 patients within 12 months (estimated incidence by Cox proportional hazard model 0.49%, 95% CI 0.29–0.69%) and in 54 patients within 54 months (estimated incidence from Cox proportional hazard model 1.35%, 95% CI 0.92–1.77%). During the study period, the incidence rates of each component of the primary composite outcome were 0.04% (0.2 events per 1000 person-years) for cardiovascular death, 0.51% (2.2 events per 1000 person-years) for nonfatal myocardial infarction, and 0.61% (2.5 events per 1000 person-years) for nonfatal ischemic stroke. The incidence of all-cause mortality was 0.82% (3.2 events per 1000 person-years) and the incidences of other cardiovascular events were all less than 0.3%. In conclusion, T2DM patients who received gemigliptin exhibited a low incidence of the primary composite MACE and all-cause mortality. Therefore, the use of gemigliptin is expected to be safe without an increase in cardiovascular risk.

Trial registration: The study was registered at ClinicalTrials.gov (identifier: NCT02290301).

Reporting and variability of constructing medication treatment episodes in pharmacoepidemiology studies: A methodologic systematic review using the case study of DPP-4 inhibitors and cardiovascular outcomes

PURPOSE

In pharmacoepidemiologic studies, estimating medication adherence, persistence, and exposure patterns is critical. Constructing medication treatment episodes from prescription claims data involves assumptions related to grace period, carry-over, and lag effect, but there are no guidelines for these assumptions. We evaluated reporting and variability of these parameters in pharmacoepidemiology studies, using a case study of antihyperglycemic medications and major adverse cardiovascular events (MACE).

METHODS

We conducted a systemic review using MEDLINE and EMBASE for studies published prior to January 2, 2020 comparing the risk of MACE between dipeptidyl peptidase 4 (DPP-4) inhibitors and active comparators. We extracted study characteristics and results, including grace period, carry-over, and lag effect. Risk of bias was assessed by the Newcastle-Ottawa scale, and assessments for prevalent user, immortal time, time lag, and time window biases.

RESULTS

A total of 14/1850 studies identified were included. Grace period was not reported in 5 (35.7%) studies and ranged from 0 days to 180 days when reported. Carry-over was not reported in 10 studies (71.4%). Lag effect was not reported in nine (71.4%) studies and ranged from 0 days to 180 days when reported. No studies conducted sensitivity analyses examining the effects of these assumptions on study findings. Predominant biases were inadequate follow-up time, comparability of cohorts, prevalent use, and lag time bias.

CONCLUSIONS

Use of grace period, carry-over, and lag effect were poorly reported and highly variable. Future pharmacoepidemiology studies should improve reporting, justify ranges for these parameters, and conduct sensitivity analyses to evaluate effects of these assumptions.

Cardiovascular risk following metformin treatment in patients with type 2 diabetes mellitus: Results from meta-analysis

AIM

Pharmacologic therapy for T2DM has proven benefits in terms of reducing elevated blood glucose levels and reducing microvascular complications. However, the impact of metformin on adverse cardiovascular outcomes and cardiovascular mortality is less clear. We carried out this meta-analysis on all published studies to estimate the overall cardiovascular risk following metformin treatment in patients with T2DM.

METHODS

We searched the PubMed, Embase and CNKI (China National Knowledge Infrastructure) databases for all articles. The odds ratio (OR) corresponding to the 95% confidence interval (95% CI) was used to assess the cardiovascular risk following metformin treatment in patients with T2DM. The statistical heterogeneity among studies was assessed with the Q-test and I² statistics.

RESULTS

We collected 16 studies including 25 comparisons with 1,160,254 patients of type 2 diabetes mellitus and 701,843 patients of T2DM following metformin treatment. Our results found statistical evidence of significantly decreased cardiovascular risk to be associated with following treatment with metformin in patients with type 2 diabetes mellitus (OR = 0.57, 95% CI = 0.48-0.68) (shown in Table 1 and Fig. 2), both with the mortality (OR = 0.44, 95% CI = 0.34-0.57) and incidence (OR = 0.73, 95% CI = 0.59-0.90).

CONCLUSIONS

Our meta-analysis indicated that following metformin treatment in patients with T2DM was associated with decreased cardiovascular risk, both with the mortality and incidence. However, the heterogeneity among studies may potentially affect the final results.

Comparison of effectiveness and drug cost between dipeptidyl peptidase-4 inhibitor and biguanide as the first-line anti-hyperglycaemic medication among Japanese working generation with type 2 diabetes

AIMS AND OBJECTIVES

Dipeptidyl peptidase-4 inhibitor (DPP4i) is widely used for the treatment of type 2 diabetes (T2DM) in several countries such as Japan, whereas biguanide (BG; mostly metformin) is recommended as a first-line antidiabetic medication in many countries according to evidence mainly from Western countries. Although previous studies reported that DPP4i may be more efficacious for East Asians, direct comparisons of effectiveness and cost between DPP4i and BG have never been conducted in East Asia.

METHODS

We extracted claims and medical check-up data (observation period from January 2010 to March 2016) of adult patients under 70 years old with T2DM who received DPP4i or BG as first-line antidiabetic drugs. Changes in HbA1c and BMI before and 2 years after the first prescription and annual cost of antidiabetic medication during the second year were compared between the DPP4i and BG groups.

RESULTS

We extracted 1034 patients who received DPP4i and 365 patients who received BG as the first antidiabetic medication (male sex, 83.0% and 84.9%; HbA1c (mean [SD]), 7.7 [1.4]% and 7.9 [1.4]%; BMI, 26.6 [4.5] kg/m² and 28.1 [4.3] kg/m² ). After propensity score matching, changes in HbA1c and BMI were not significantly different between the groups (HbA1c, -0.67% vs -0.80% [P = .28]; BMI, -0.3 kg/m² vs -0.4 kg/m² [P = .42]). Annual cost of antidiabetic drugs was significantly higher in the DPP4i group (US $458.7 vs 273.3 [P < .001]). Many patients continued each medication at the follow-up visit (78.3% of the DPP4i group and 73.7% of the BG groups).

CONCLUSIONS

The first antidiabetic prescription for the patient was mostly continued thereafter. BG may be recommendable as the first-line medication for patients with T2DM, especially for middle-aged, male population with greater BMI. It is worth addressing the discrepancy between practice in Japan and that recommended in international guidelines.

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.

The impact of DPP-4 inhibitors on long-term survival among diabetic patients after first acute myocardial infarction

Background

Previous studies regarding the cardioprotective effects of dipeptidyl peptidase 4 (DPP-4) inhibitors have not provided sufficient evidence of a relationship between DPP-4 inhibition and actual cardiovascular outcomes. This study aimed to evaluate the impact of DPP-4 inhibitors on the survival of diabetic patients after first acute myocardial infarction (AMI).

Methods

This was a nationwide, propensity score-matched, case–control study of 186,112 first AMI patients, 72,924 of whom had diabetes. A propensity score, one-to-one matching technique was used to match 2672 controls to 2672 patients in the DPP-4 inhibitor group for analysis. Controls were matched based on gender, age, and a history of hypertension, dyslipidemia, diabetes, peripheral vascular disease, heart failure, cerebrovascular accident, end-stage renal disease, chronic obstructive pulmonary disease, and percutaneous coronary intervention.

Results

DPP-4 inhibitors improve the overall 3-year survival rate (log rank P < 0.0001), whether male or female. Cox proportional hazard regression showed DPP-4 inhibitor is beneficial in diabetes patients after AMI (HR = 0.86; 95% CI 0.78–0.95), especially in those patients with hypertension (HR = 0.87; 95% CI 0.78–0.97; P = 0.0103) and cerebrovascular disease (HR = 0.83; 95% CI 0.72–0.97; P = 0.018), but without dyslipidemia (HR = 0.78; 95% CI 0.67–0.92; P = 0.0029), without peripheral vascular disease (HR = 0.86; 95% CI 0.78–0.96; P = 0.0047), without heart failure (HR = 0.84; 95% CI 0.73–0.96; P = 0.0106), without end stage renal disease (HR = 0.86; 95% CI 0.77–0.95; P = 0.0035), and without chronic obstructive pulmonary disease (HR = 0.87; 95% CI 0.78–0.97; P = 0.0096).

Conclusions

DPP-4 inhibitor therapy improved long-term survival in diabetic patients after first AMI, regardless of gender.

Comparative safety for cardiovascular outcomes of DPP-4 inhibitors versus glimepiride in patients with type 2 diabetes: A retrospective cohort study

Concerns about the cardiovascular safety of dipeptidyl peptidase-4 (DPP-4) inhibitors persist. This study sought to determine whether there is a differential risk of hospitalization for cardiovascular diseases (CVDs) between DPP-4 inhibitors and glimepiride.We conducted this retrospective cohort study by using the Korean National Health Insurance Service database from December 1, 2008, to December 31, 2013. The study subjects were new users of DPP-4 inhibitors or glimepiride for type 2 diabetes. Outcome was defined as hospitalization for CVDs, including angina pectoris, myocardial infarction, transient cerebral ischemic attack, heart failure, or cerebrovascular disease or any procedure involving coronary artery bypass grafting or percutaneous coronary intervention. We used a Cox proportional hazard model to estimate the adjusted hazard ratios (aHRs) and their 95% confidence intervals (CIs), to assess the risk of CVDs associated with the use of DPP-4 inhibitors compared with glimepiride.The cohort consisted of 1,045,975 patients, with 6504 in the DPP-4 inhibitors group and 13,447 in the glimepiride group. No significant increased risk of total CVDs was found (aHR, 0.87; 95% CI, 0.75-1.01) in the DPP-4 inhibitors versus glimepiride group. A decreased risk of hospitalization for CVDs was found among patients with a history of visit for CVDs (aHR, 0.73; 95% CI, 0.56-0.97) or with >2.5 years' duration of type 2 diabetes (aHR, 0.77; 95% CI, 0.66-0.91) in the DPP-4 inhibitors versus glimepiride group.DPP-4 inhibitors did not increase cardiovascular risk compared with glimepiride regardless of CVD history and diabetes duration.

Association of Sitagliptin with cardiovascular outcome in diabetic patients: a nationwide cohort study

AIMS

Although dipeptidyl peptidase-4 (DPP-4) inhibitor improves glycemic control, the actual cardiovascular outcomes remain unclear. The objective of this cohort study was to thus evaluate the cardiovascular outcome in diabetic patients who received DPP-4 inhibitors (Sitagliptin).

METHODS

A total of 104,756 new diabetic patients were identified from the Taiwan National Health Insurance Research Database during the period from March 1, 2003 to December 31, 2011. Patients who received Sitagliptin therapy were included as exposures, and up to four age- and sex-matched controls were selected by risk-set sampling. Outcomes such as major adverse cardiovascular diseases (CVD) and deaths were assessed. Logistic regression models were applied to estimate the hazard ratios and 95 % CIs between DPP-4 inhibitor use and cardiovascular outcome.

RESULTS

Over a mean of 14 months, the rates of total CVD per 1000 person-months were significantly lower in Sitagliptin users (3.41 vs. 5.17, p < 0.001), whereas other different CVDs (hazard ratio [HR] 0.59; 95 % confidence interval [CI] 0.48-0.72 for coronary heart disease; HR 0.75; 95 % CI 0.59-0.96 for ischemic stroke; HR 0.86; 95 % CI 0.45-1.65 for peripheral artery occlusive disease) and all-cause mortality (HR 0.56; 95 % CI 0.41-0.74]) were also fewer after adjustment for covariates.

CONCLUSIONS

The results showed a favorable outcome of Sitagliptin as a class on lowering CVD incidence in patients with type 2 diabetes.

Association Between Hospitalization for Heart Failure and Dipeptidyl Peptidase 4 Inhibitors in Patients With Type 2 Diabetes: An Observational Study

OBJECTIVE

To examine, among patients with type 2 diabetes, the association between hospitalization for heart failure (hHF) and treatment with dipeptidyl peptidase 4 inhibitors (DPP-4is) versus sulfonylureas (SUs), and treatment with saxagliptin versus sitagliptin.

RESEARCH DESIGN AND METHODS

This was a retrospective, observational study using a U.S. insurance claims database. Patients initiated treatment between 1 August 2010 and 30 August 2013, and had no use of the comparator treatments in the prior 12 months (baseline). Each comparison consisted of patients matched 1:1 on a propensity score. Time to each outcome was compared between matched groups using Cox models. Analyses were stratified by the presence of baseline cardiovascular disease (CVD). Secondary analyses examined associations between comparator treatments and other selected cardiovascular events.

RESULTS

After matching, the study included 218,556 patients in comparisons of DPP-4i and SU, and 112,888 in comparisons of saxagliptin and sitagliptin. The hazard ratios (HRs) of hHF were as follows: DPP-4i versus SU (reference): HR 0.95 (95% CI 0.78-1.15), P = 0.580 for patients with baseline CVD; HR 0.59 (95% CI 0.38-0.89), P = 0.013 for patients without baseline CVD; saxagliptin versus sitagliptin (reference): HR 0.95 (95% CI 0.70-1.28), P = 0.712 for patients with baseline CVD; HR 0.99 (95% CI 0.56-1.75), P = 0.972 for patients without baseline CVD. Comparisons of the individual secondary and composite cardiovascular outcomes followed a similar pattern.

CONCLUSIONS

In patients with type 2 diabetes, there was no association between hHF, or other selected cardiovascular outcomes, and treatment with a DPP-4i relative to SU or treatment with saxagliptin relative to sitagliptin.

Sitagliptin After Ischemic Stroke in Type 2 Diabetic Patients: A Nationwide Cohort Study

The cerebrovascular safety and efficacy of sitagliptin, a dipeptidyl peptidase-4 inhibitor, in patients with type 2 diabetes mellitus (T2DM) with ischemic stroke remains uncertain. The aim of this study was to assess the efficacy and safety of sitagliptin in patients with T2DM with recent ischemic stroke. We analyzed data from the Taiwan National Health Insurance Research Database between March 1, 2009, and December 31, 2011. Ischemic stroke patients were identified from individuals with T2DM. Patients who received sitagliptin were compared with those who did not to evaluate the cardiovascular safety and efficacy of sitagliptin. The primary outcome was a composite of ischemic stroke, myocardial infarction, or cardiovascular death. A total of 5145 type 2 diabetic patients with ischemic stroke met our inclusion criteria and were followed for up to 2.83 years (mean, 1.17 years). Overall, 1715 patients (33.3%) received sitagliptin and 3430 patients (66.7%) did not. The primary composite outcome occurred in 190 patients in the sitagliptin group (11.1%) and in 370 patients in the comparison group (10.8%) (hazard ratio [HR] = 1.02; 95% confidence interval [CI], 0.85-1.21). Patients treated with sitagliptin had a similar risk of ischemic stroke, hemorrhagic stroke, and all-cause mortality with an HR of 0.95 (95% CI, 0.78-1.16, P = 0.612), 1.07 (95% CI, 0.55-2.11, P = 0.834), and 1.00 (95% CI, 0.82-1.22, P = 0.989), respectively, compared with patients not treated with sitagliptin. Treatment with sitagliptin in type 2 diabetic patients with recent ischemic stroke was not associated with increased or decreased risks of adverse cerebrovascular outcomes.

Cardiovascular Outcomes of Sitagliptin in Type 2 Diabetic Patients with Acute Myocardial Infarction, a Population-Based Cohort Study in Taiwan

Background

The cardiovascular safety and efficacy of sitagliptin, a dipeptidyl peptidase 4 (DPP-4) inhibitor, in type 2 diabetic patients after acute myocardial infarction (AMI) has so far remained uncertain.

Methods

We analyzed data from the National Health Insurance Research Database (NHIRD), a government-operated, population-based database, from March 1st, 2009 to December 31st, 2011. Type 2 diabetic patients hospitalized for AMI were included in our study. We compared subjects using sitagliptin with comparison group to evaluate its cardiovascular safety and efficacy. The primary endpoint was a composite of cardiovascular death, myocardial infarction, and ischemic stroke.

Results

We identified a total of 3,282 type 2 diabetic patients hospitalized for AMI (mean follow-up 1.15 years). Of these patients, 547 (16.7%) who were exposed to sitagliptin were defined as the sitagliptin group and 2,735 (83.3 %) who did not use sitagliptin were the comparison group. The incidence of primary composite cardiovascular outcomes was 9.50 per 100 person-years in the sitagliptin group and was 9.70 per 100 person-years in the comparison group (hazard ratio (HR), 0.97; 95% CI, 0.73–1.29, P=0.849). Compared to the non-sitagliptin group, the sitagliptin group had similar risks of all-cause mortality, hospitalization for heart failure (HF) or percutaneous coronary intervention (PCI) with a HR of 0.82 (95% CI, 0.61–1.11, P=0.195), 0.93 (95% CI, 0.67–1.29, P=0.660), and 0.93 (95% CI, 0.75–1.14, P=0.473), respectively.

Conclusion

The use of sitagliptin in type 2 diabetic patients with recent AMI was not associated with increased risk of adverse cardiovascular events.

DPP-4 inhibitors: focus on safety

INTRODUCTION

Dipeptidyl peptidase inhibitors (DPP-4-i) are highly selective inhibitors of the enzyme DPP-4. They act by increasing levels of incretin hormones, which have potent effects on insulin and glucagon release, gastric emptying, and satiety. Our goal is to review the safety issues related to DPP-4-i.

AREAS COVERED

This review is based upon a PubMed search of the literature using keywords alogliptin, linagliptin, saxagliptin, sitagliptin and vildagliptin, DPP-4-i, glucagon-like polypeptide-1 agonists, as well as extensive personal clinical trial experience with each of these agents. The current DPP-4-i have very different chemical structures. Saxagliptin has significant cytochrome P450 metabolism and carries a risk of drug interactions. Linagliptin has primarily entero-hepatic excretion, a benefit in renally impaired patients. A concern arose related to congestive heart failure in the SAVOR TIMI trial of saxagliptin. Several major cardiac studies are underway, with two concluded. Despite lingering uncertainty related to pancreatitis and pancreatic cancer, large randomized trials have not shown an increased risk with DPP-4-i treatment. Cutaneous adverse effects occur with a low frequency with some of these agents.

EXPERT OPINION

DPP-4-i are an additional choice in the group of anti-hyperglycemics. Their principal advantage is a low incidence of hypoglycemia, making these agents desirable in patients such as the elderly and those with cardiac disease. Several large trials have hinted at less cardiac risk with DPP-4-i than with sulfonylureas. The CAROLINA Trial comparing linagliptin and glimepiride may provide a conclusive answer to this question.

Sitagliptin and cardiovascular outcomes in diabetic patients with chronic kidney disease and acute myocardial infarction: A nationwide cohort study

BACKGROUND

The cardiovascular safety and efficacy of sitagliptin, a dipeptidyl peptidase 4 (DPP-4) inhibitor, in type 2 diabetic patients with chronic kidney disease (CKD) after acute myocardial infarction (AMI) are unclear.

METHODS

We analyzed data from the Taiwan National Health Insurance Research Database between March 1st, 2009 and December 31st, 2011. A total of 1025 AMI patients with diabetes with chronic kidney disease were selected as the study cohort. The study evaluated the cardiovascular safety and efficacy of sitagliptin by comparing 205 subjects (20%) who use sitagliptin to 820 matched subjects (80%) who do not. The primary outcomes included myocardial infarction, ischemic stroke or cardiovascular death.

RESULTS

Primary composite outcomes occurred in 54 patients in the sitagliptin group (26.3%) and in 164 patients in the comparison group (20.0%) (HR, 1.32; 95% CI, 0.97-1.79; P=0.079) during the mean follow-up of 1.02years (SD=0.71years). The sitagliptin group had similar risks of ischemic stroke, all-cause mortality or hospitalization for heart failure (HF) compared to the non-sitagliptin group (P=0.938, 0.523 and 0.795 respectively). However, sitagliptin use was associated with increased risks of recurrent myocardial infarction (HR, 1.73; 95% CI, 1.15-2.58; P=0.008) and percutaneous coronary revascularization (HR, 1.43; 95% CI, 1.04-1.95; P=0.026).

CONCLUSIONS

Among type 2 diabetic patients with CKD after AMI, the use of sitagliptin was not associated with an increased risk of cardiovascular death, ischemic stroke or hospitalization for HF but was associated with increased risks of recurrent MI and percutaneous coronary revascularization.

Antiatherothrombotic effects of dipeptidyl peptidase inhibitors

Atherothrombotic cardiovascular events are a leading cause of morbidity and mortality in patients with type 2 diabetes (T2D). A number of factors beyond hyperglycemia contribute to this increased risk of cardiovascular events in T2D, including elevated blood pressure, dyslipidemia, inflammation, endothelial dysfunction, and enhanced platelet activation. Importantly, most currently available antihyperglycemic treatments for T2D do not address these additional mechanisms. Indeed, we posit that this may explain why more intensive treatment of hyperglycemia has not contributed to a reduced incidence of cardiovascular events in subjects with T2D. Incretin-targeted therapies, such as dipeptidyl peptidase 4 inhibitors, are a relatively new class of antidiabetic treatments, and preclinical as well as small mechanistic clinical studies suggest that they exert beneficial cardiovascular effects. This review focuses specifically on the potential antiatherothrombotic effects of dipeptidyl peptidase 4 inhibitors.

Cardiovascular safety of combination therapies with incretin-based drugs and metformin compared with a combination of metformin and sulphonylurea in type 2 diabetes mellitus--a retrospective nationwide study

AIM

Dipeptidyl peptidase-4 (DPP-4) inhibitors and glucagon-like peptide-1 (GLP-1) agonists are widely used in combinations with metformin in the treatment of type 2 diabetes; however, data on long-term safety compared with conventional combination therapies are limited.

METHODS

Danish individuals without prior myocardial infarction or stroke that initiated combinations of metformin with sulphonylurea (SU), DPP-4 inhibitors, GLP-1 agonists or insulin between 9 May 2007 and 31 December 2011 were followed up for the risk of all-cause mortality, cardiovascular (CV) mortality or a combined end point of myocardial infarction, stroke and CV mortality. Rate ratios (RR) were calculated using time-dependent multivariable Poisson regression analysis.

RESULTS

A total of 40 028 patients (59% men, mean age 60 ± 13 years) used metformin with SU (n = 25 092), DPP-4 inhibitor (n = 11 138), GLP-1 agonist (n = 4345) or insulin (n = 6858). Crude incidence rates per 1000 patient years for the combined end point were 18 (SU), 10 (DPP-4 inhibitor), 8 (GLP-1 agonist) and 21 (insulin). In adjusted analyses with metformin + SU as reference, metformin + DPP-4 inhibitor was associated with an RR of 0.65 (0.54-0.80) for mortality, an RR of 0.57 (0.40-0.80) for CV mortality and an RR of 0.70 (0.57-0.85) for the combined end point. For metformin + GLP-1 agonist, the RR for mortality was 0.77 (0.51-1.17), for CV mortality 0.89 (0.47-1.68), and for the combined end point 0.82 (0.55-1.21).

CONCLUSION

Incretin-based drugs combined with metformin were safe compared with conventional combinations of glucose-lowering therapy. Use of incretin-based therapy may be target for strategies to lower CV risk in type 2 diabetes, although it should be recognized that the multivariable analysis may not have fully accounted for important baseline differences.