Dipeptidyl Peptidase 4 Inhibitors and the Risk of Cardiovascular Disease in Patients with Type 2 Diabetes: A Tale of Three Studies

Association of Baseline HbA1c With Cardiovascular and Renal Outcomes: Analyses From DECLARE-TIMI 58

OBJECTIVE

Current guidelines recommend prescribing SGLT2 inhibitors to patients with type 2 diabetes and established or at high risk for atherosclerotic cardiovascular disease (ASCVD), irrespective of HbA1c levels. We studied the association of HbA1c with cardiovascular and renal outcomes and whether the benefit of dapagliflozin varies by baseline HbA1c.

RESEARCH DESIGN AND METHODS

In the Dapagliflozin Effect on Cardiovascular Events trial (DECLARE-TIMI 58), 17,160 patients with type 2 diabetes were randomly assigned to dapagliflozin or placebo for a median follow-up of 4.2 years. Cardiovascular and renal outcomes by baseline HbA1c in the overall population and with dapagliflozin versus placebo in HbA1c subgroups were studied by Cox regression models.

RESULTS

In the overall population, higher baseline HbA1c was associated with a higher risk of cardiovascular death or hospitalization for heart failure (HHF); major adverse cardiovascular events (MACE), including cardiovascular death, myocardial infarction, and ischemic stroke; and cardiorenal outcomes (adjusted hazard ratios 1.12 [95% CI 1.06-1.19], 1.08 [1.04-1.13], and 1.17 [1.11-1.24] per 1% higher level, respectively). Elevated HbA1c was associated with a greater increased risk for MACE and cardiorenal outcomes in patients with multiple risk factors (MRF) than in established ASCVD (P-interaction = 0.0064 and 0.0093, respectively). Compared with placebo, dapagliflozin decreased the risk of cardiovascular death/HHF, HHF, and cardiorenal outcomes, with no heterogeneity by baseline HbA1c (P-interaction > 0.05).

CONCLUSIONS

Higher HbA1c levels were associated with greater cardiovascular and renal risk, particularly in the MRF population, yet the benefits of dapagliflozin were observed in all subgroups irrespective of baseline HbA1c, including patients with HbA1c <7%.

Comparative Cardiovascular Outcomes of SGLT2 Inhibitors in Type 2 Diabetes Mellitus: A Network Meta-Analysis of Randomized Controlled Trials

BACKGROUND

A network meta-analysis of randomized controlled trials (RCTs) was conducted to explore the cardiovascular outcomes of all the kind and dosages of sodium-glucose cotransport-2 (SGLT2) inhibitors in type 2 diabetes mellitus (T2DM) patients.

METHOD AND RESULT

The Cochrane Library, PubMed, and Embase databases were systematically searched for studies to compare the therapeutic effects of different SGLT2 inhibitors in T2DM patients. The effect measurements estimate chosen were odds ratios (ORs) and their corresponding 95% confidence interval (CI). Forty-seven RCTs involving a total of 70574 participants were eligible for direct and indirect comparisons. In direct comparison, treatment with dapagliflozin 5mg showed significantly lower risk of all-cause mortality compared with treatment with dapagliflozin 2.5mg (OR 0.09, 95% CI 0.01-0.70). According to NMA, interestingly, empagliflozin 10mg/25mg, and canagliflozin 100mg was associated with significantly lower risks of all-cause mortality compared with placebo (OR of 0.70, 95% CI 0.58-0.85; 0.69, 95% CI 0.57-0.84; and 0.83, 95% CI 0.73-0.95, respectively). Compared with placebo, dapagliflozin 10mg, empagliflozin 10mg and 25mg displayed the lower risks for cardiovascular events (OR 0.78, 95% CI 0.44-1.00; OR 0.47, 95% CI 0.22-0.93; and 0.43, 95% CI 0.24-0.74, respectively) by direct comparison. Moreover, canagliflozin 100/300mg showed significantly higher risks of cardiovascular events compared with empagliflozin 10mg (OR of 4.83, 95% CI 1.14-20.46 and 5.31, 95% CI 1.26-22.34, respectively) and empagliflozin 25mg (4.23, 95% CI 1.13-15.83 and 4.65, 95% CI 1.25-17.27, respectively) according to NMA. There were non-significant differences among all interventions in volume depletion in traditional pairwise meta-analysis. While in NMA, canagliflozin 100/300mg were associated with significantly increased risks of volume depletion compared with placebo (OR of 1.47, 95% CI 1.08-1.99 and 2.19, 95% CI 1.66-2.90, respectively).

CONCLUSION

In the limitations of the NMA, this study showed that empagliflozin might be better than other SGLT2 inhibitors with low risks of all-cause mortality and cardiovascular events in patients with T2DM suggesting the need for ad hoc RCTs.

Sodium-Glucose Cotransporter-2 Inhibitor Use is Associated with a Reduced Risk of Heart Failure Hospitalization in Patients with Heart Failure with Preserved Ejection Fraction and Type 2 Diabetes Mellitus: A Real-World Study on a Diverse Urban Population

BACKGROUND

Limited evidence-based therapies exist for the management of heart failure with preserved ejection fraction (HFpEF). Sodium-glucose cotransporter-2 inhibitor (SGLT2i) use in patients with systolic heart failure (HFrEF) and type-2-diabetes mellitus (T2DM) is associated with improved cardiovascular (CV) and renal outcomes.

OBJECTIVE

We sought to examine whether there is an association of SGLT2i use with improved CV outcomes in patients with HFpEF.

PATIENTS AND METHODS

We conducted a single-center, retrospective review of patients with HFpEF and T2DM. The cohort was divided into two groups based on prescription of a SGLT2i or sitagliptin. The primary outcome was heart failure hospitalization (HFH); secondary outcomes were all-cause hospitalization and acute kidney injury (AKI).

RESULTS

After propensity score matching, there were 250 patients (89 in the SGLT2i group, 161 in the sitagliptin group), with a mean follow-up of 295 days. Univariate Cox regression analysis showed that the SGLT2i group had a reduced risk of HFH versus the sitagliptin group (hazard ratio (HR) 0.13; 95% confidence interval (CI) (0.05-0.36); p < 0.001). The SGLT2i group had a decreased risk of all-cause hospitalization (HR 0.48; 95% CI (0.33-0.70); p < 0.001) and SGLT2i had a lower risk of AKI (HR 0.39; 95% CI (0.20-0.74); p = 0.004).

CONCLUSIONS

The use of SGLT2is is associated with a reduced incidence of HFH and AKI in patients with HFpEF and T2DM.

Effect of Switching from Linagliptin to Teneligliptin Dipeptidyl Peptidase-4 Inhibitors in Older Patients with Type 2 Diabetes Mellitus

INTRODUCTION

Dipeptidyl peptidase-4 (DPP-4) inhibitors are widely prescribed for type 2 diabetes (T2D) and their glycemic control effects are well studied. However, information regarding the effects of switching DPP-4 inhibitors is limited, especially in older patients.

RESEARCH DESIGN AND METHODS

We investigated whether switching from linagliptin to teneligliptin decreases blood glucose in older (≥65 years) T2D patients. In total, 164 patients with T2D who switched from linagliptin to teneligliptin for >12 weeks were included and the primary outcome was glycemic changes.

RESULTS

Switching from linagliptin to teneligliptin ameliorated fasting blood glucose (148.1 ± 47.1 to 139.6 ± 43.4 mg/dL), glycated hemoglobin (HbA1c; 7.9 ± 1.3 to 7.5 ± 1.2%), and postprandial blood glucose (224.8 ± 77.4 to 205.8 ± 70.8 mg/dL) levels (all P < 0.05). Low-density lipoprotein cholesterol concentration was reduced while liver and kidney functions were maintained. Subgroup analysis showed that glucose control improved more in patients with uncontrolled hyperglycemia (HbA1c > 8.0%) and chronic kidney disease (estimated glomerular filtration rate <90 mL/min/1.73m2). Multiple logistic analysis indicated higher baseline HbA1c was the strongest predictor of teneligliptin switching response.

CONCLUSION

Switching from linagliptin to teneligliptin helps maintain kidney function and reduce blood glucose safely in older patients with T2D.

Glucagon secretion determined by the RIA method is lower in patients with low left ventricular ejection fraction: The new glass study

AIMS

We investigated the glucagon levels in patients with heart failure (HF), using long oral glucose tolerance test (OGTT).

METHODS

In this prospective observational study, we enrolled 30 undiagnosed diabetes patients (age 69 ± 10 years, 70% males, HbA1c 43 mmol/mol). A 4-h OGTT was performed. Glucose, insulin, and glucagon (radioimmunoassay [RIA] and sandwich ELISA [S-W] methods) were evaluated during 4-h. We compared glucagon levels between HF and non-HF patients.

RESULTS

There were 11 HF and 19 non-HF patients. In patients with HF, glucagon (S-W) during 4-h was lower than in patients without HF, with no significant difference. The area under the curve (AUC) of glucagon (RIA) during 4-h was significantly lower among HF patients. Moreover, in patients with reduced left ventricular ejection fraction (LVEF) (<40%), AUC glucagon (RIA) was significantly lower than in patients with non-reduced EF (≥40%). However, there was no difference in glucagon values between the high E/e' (≥13.0) and low E/e' (<13.0) groups.

CONCLUSIONS

Although glucagon (S-W) showed no significant difference in patients with and without HF, especially reduced LVEF, glucagon (RIA) secretion was significantly lower in HF patients than in patients without HF. It is suggested that low glucagon secretion might be correlated with low EF.

Dipeptidyl peptidase-4 inhibitor use and risk of diabetic retinopathy: A population-based study

AIMS

This study examined whether dipeptidyl peptidase (DPP)-4 inhibitor use is beneficial or harmful to diabetic retinopathy (DR) compared with other glucose-lowering agents in patients with type 2 diabetes (T2D).

METHODS

From a population-based cohort provided by the National Health Insurance Service in Korea, 67,743 adults with T2D were identified as having been treated with oral glucose-lowering agents between 2008 and 2013. Matching (1:1) was performed for two groups comparing ever-use (cases) and never-use (controls) of DPP-4 inhibitors (n=14,522 in each group). Cox regression analyses were used to assess risk of the following DR events: vitreous haemorrhage; vitrectomy or photocoagulation; intravitreal agent use; and blindness.

RESULTS

During a median follow-up of 28.4 (14.0-45.2) months, there were 305 (in controls) and 342 (in cases) composite DR events. DPP-4 inhibitor ever-use was not associated with overall risk of composite DR events [adjusted hazard ratio (HR): 1.08, 95% CI: 0.93-1.26] compared with never-use, nor was the risk of each DR outcome increased with DPP-4 inhibitor therapy either. However, DPP-4 inhibitor administration for<12 months was associated with a greater risk of composite DR events (adjusted HR: 1.31, 95% CI: 1.09-1.57) compared with other glucose-lowering agents over the same treatment period.

CONCLUSION

In comparison to other oral glucose-lowering agents, DPP-4 inhibitor treatment did not increase overall risk of DR. However, DPP-4 inhibitors may be associated with an increased risk of retinopathy events early in the treatment phase.

Dipeptidyl peptidase-4 inhibitors and incidence of inflammatory bowel disease among patients with type 2 diabetes: population based cohort study

OBJECTIVE

To assess whether the use of dipeptidyl peptidase-4 inhibitors is associated with the incidence of inflammatory bowel disease in patients with type 2 diabetes.

DESIGN

Population based cohort study.

SETTING

More than 700 general practices contributing data to the United Kingdom Clinical Practice Research Datalink.

PARTICIPANTS

A cohort of 141 170 patients, at least 18 years of age, starting antidiabetic drugs between 1 January 2007 and 31 December 2016, with follow-up until 30 June 2017.

MAIN OUTCOME MEASURES

Adjusted hazard ratios for incident inflammatory bowel disease associated with use of dipeptidyl peptidase-4 inhibitors overall, by cumulative duration of use, and by time since initiation, estimated using time dependent Cox proportional hazards models. Use of dipeptidyl peptidase-4 inhibitors was modelled as a time varying variable and compared with use of other antidiabetic drugs, with exposures lagged by six months to account for latency and diagnostic delays.

RESULTS

During 552 413 person years of follow-up, 208 incident inflammatory bowel disease events occurred (crude incidence rate of 37.7 (95% confidence interval 32.7 to 43.1) per 100 000 person years). Overall, use of dipeptidyl peptidase-4 inhibitors was associated with an increased risk of inflammatory bowel disease (53.4 v 34.5 per 100 000 person years; hazard ratio 1.75, 95% confidence interval 1.22 to 2.49). Hazard ratios gradually increased with longer durations of use, reaching a peak after three to four years of use (hazard ratio 2.90, 1.31 to 6.41) and decreasing after more than four years of use (1.45, 0.44 to 4.76). A similar pattern was observed with time since starting dipeptidyl peptidase-4 inhibitors. These findings remained consistent in several sensitivity analyses.

CONCLUSIONS

In this first population based study, the use of dipeptidyl peptidase-4 inhibitors was associated with an increased risk of inflammatory bowel disease. Although these findings need to be replicated, physicians should be aware of this possible association.

DPP4 inhibitors and cardiovascular outcomes: safety on heart failure

Diabetes is an important risk factor for cardiovascular disease. However, clinical data suggests intensive glycemic control significantly increase rather than decrease cardiovascular mortality, which is largely due to the fact that a majority of oral anti-diabetic drugs have adverse cardiovascular effect. There are several large-scale clinical trials evaluating the cardiovascular safety of DPP4 inhibitors, a novel class of oral anti-diabetic medications, which have been recently completed. They were proven to be safe with regard to cardiovascular outcomes. However, concerns on the safety of heart failure have been raised as the SAVOR-TIMI 53 trial reported a 27% increase in the risk for heart failure hospitalization in diabetic patients treated with DPP4 inhibitor saxagliptin. In this review, we will discuss recent advances in the heart failure effects of DPP4 inhibition and GLP-1 agonism.

Management of diabetes in older adults

Type 2 diabetes prevalence is high in older adults and is expected to rise in the next decades. Diabetes in the population of frail older adults is accompanied by functional disability, several comorbidities, and premature mortality. A comprehensive geriatric assessment, including functional, cognitive, mental and social status, is advisable for identifying the glycemic targets and glucose-lowering therapies, focused on patient preferences, needs, and risks. The therapeutic options for older adults with diabetes are like those for the adult population. However, the pharmacological treatments must be carefully prescribed and monitored, taking into consideration the patient cognitive capacities, the potentially life-threatening drug-drug interactions, the cardiovascular risk, and with the main goal of avoiding hypoglycemia. Also, a careful nutritional evaluation with appropriate tools, as well as a balanced and periodically monitored physical activity, contribute to an effective tailored care plan, as needed by older adults with diabetes. This review evaluates the currently available hypoglycemic drugs and the current indications to the Italian diabetology community, specifically with regard to the treatment of adults aged 75 years or older with diabetes, including the unmet needs by the guidelines.

Assessment of Cardiovascular Risk With Glucagon-Like Peptide 1 Receptor Agonists in Patients With Type 2 Diabetes Using an Alternative Measure to the Hazard Ratio

Background: Randomized clinical trials with the aim of evaluating the cardiovascular risks associated with glucagon-like peptide 1 (GLP-1) receptor agonists, lixisenatide, liraglutide, semaglutide, and exenatide, have been conducted. They showed different results among the agents, but the reason has not been explained. Objective: To evaluate the cardiovascular risks associated with GLP-1 receptor agonists by using an alternative measure to the hazard ratio. Methods: We used the difference in restricted mean survival time (RMST) as a measure of cardiovascular risks. Four randomized clinical trials with cardiovascular events as a primary endpoint, ELIXA (lixisenatide), LEADER (liraglutide), SUSTAIN-6 (semaglutide), and EXSCEL (exenatide), were reevaluated by estimating the RMSTs for each of the agents and placebo based on the reconstructed individual patient data for each time-to-event outcome from publicly available information. Results: The differences of RMSTs (GLP-1 receptor agonist minus placebo: point estimate and 95% CI) for primary composite endpoint of cardiovascular events were 0 days [−14, 14] in ELIXA (1080 days follow-up), 20 days [6, 34] in LEADER (1620 days follow-up), 8 days [1, 15] in SUSTAIN-6 (672 days follow-up), and 11 days [−3, 26] in EXSCEL (1825 days follow-up). As for the risk of other cardiovascular outcomes, there were no substantial differences between GLP-1 receptor agonists and placebo. Conclusions: Liraglutide and semaglutide decrease the risk of major adverse cardiovascular events compared with placebo when using the difference in RMST. The previously reported result that GLP-1 receptor agonists do not increase the risk of cardiovascular outcomes compared with placebo is also confirmed.

Postmeal increment in intact glucagon-like peptide 1 level, but not intact glucose-dependent insulinotropic polypeptide levels, is inversely associated with metabolic syndrome in patients with type 2 diabetes

PURPOSE

Metabolic syndrome increases the risk of cardiovascular disease. Recently glucagon-like peptide 1 (GLP-1) agonists proved to be effective in preventing cardiovascular disease (CVD) in patients with type 2 diabetes. We investigated the association of blood incretin levels with metabolic syndrome in patients with type 2 diabetes.

MATERIALS AND METHODS

This is a cross-sectional study involving 334 people with type 2 diabetes. Intact GLP-1 (iGLP-1) and intact glucose-dependent insulinotropic polypeptide (iGIP) levels were measured in a fasted state and 30 min after ingestion of a standard mixed meal. Metabolic syndrome was diagnosed based on the criteria of the International Diabetes Federation.

RESULTS

Two hundred twenty-five (69%) of the subjects have metabolic syndrome. The fasting iGLP-1 level was no different between groups. Thirty-min postprandial iGLP-1 was non-significantly lower in the subjects who had metabolic syndrome. Incremental iGLP-1 (ΔiGLP-1, the difference between 30-min postmeal and fasting iGLP-1 levels) was significantly lower in those with metabolic syndrome. There were no significant differences in fasting iGIP, postprandial iGIP, and ΔiGIP between groups. The ΔiGLP-1, but not ΔiGIP levels decreased significantly as the number of metabolic syndrome components increased. In hierarchical logistic regression analysis, the ΔiGLP-1 level was found to be a significant contributor to metabolic syndrome even after adjusting for other covariates.

CONCLUSION

Taken together, the iGLP-1 increment in the 30 min after meal ingestion is inversely associated with metabolic syndrome in patients with type 2 diabetes. This suggests that postmeal iGLP-1 increment could be useful in assessing cardiovascular risk in type 2 diabetes.

Coadministration of DPP-4 inhibitor and insulin therapy does not further reduce the risk of cardiovascular events compared with DPP-4 inhibitor therapy in diabetic foot patients: a nationwide population-based study

BACKGROUND

The effect of combined insulin and dipeptidyl peptidase-4 inhibitor (DPP4i) therapy on major adverse cardiovascular events (MACEs) in patients with diabetic foot is unclear.

METHODS

We conducted this nationwide cohort study using longitudinal claims data obtained from the Taiwan National Health Insurance program and included 19,791 patients with diabetic foot from 2007 to 2014. Patients receiving DPP4i-based therapy and/or insulin-based therapy after a diagnosis of diabetic foot were categorized into combined, DPP4i- or insulin-based groups, respectively. The risk of MACEs including nonfatal myocardial infarction, nonfatal stroke, cardiac death, and heart failure was assessed using Cox proportional hazards analysis and propensity score matching.

RESULTS

Among the 19,791 patients with diabetic foot (mean age, 58.8 years [SD, 12.5]; men, 51.2%), 6466 received DPP4i-based therapy, 1925 received insulin-based therapy, and 11,400 received combined DPP4i and insulin therapy. The DPP4i-based and insulin-based groups had a lower risk of MACEs (HR 0.53, 95% CI 0.50-0.57 DPP4i only; HR 0.89, 95% CI 0.81-0.97 insulin only) than the combined group. After propensity score matching, the incidence of all complications in the DPP4i-based group was still significantly lower than that in the combined group (HR 0.55, 95% CI 0.51-0.59 for MACEs; HR 0.32, 95% CI 0.24-0.42 for nonfatal myocardial infarction; HR 0.70, 95% CI 0.63-0.78 for nonfatal stroke; HR 0.22, 95% CI 0.13-0.38 for cardiac death; HR 0.22, 95% CI 0.19-0.25 for any death; HR 0.16, 95% CI 0.13-0.20 for amputation). In the diabetic foot patients with end-stage renal disease (ESRD), the benefit of a lower incidence of MACEs in the DPP4i-based group disappeared (HR 0.77, 95% CI 0.58-1.08).

CONCLUSIONS

This study demonstrated that the patients with diabetic foot receiving DPP4i-based therapy had a lower risk of MACEs than those receiving combined therapy with DPP4i and insulin, but that the effect disappeared in those with concurrent ESRD.

Treating Diabetes in Patients with Heart Failure: Moving from Risk to Benefit

Over the past two decades, therapeutics for diabetes have evolved from drugs with known heart failure risk to classes with potential benefit for patients with heart failure. As many as 25 to 35 % of patients with heart failure carry a diagnosis of type 2 diabetes mellitus. Therefore, newer drug classes including dipeptidyl peptidase 4 (DPP-4) inhibitors, glucagon-like peptide 1 (GIP-1) agonists, and sodium-glucose cotransporter 2 (SGLT-2) inhibitors are being examined for cardiovascular safety as well as their effects on left ventricular function, quality of life, and other measures of disease progression. The purpose of this review is to summarize the existing evidence on these classes of anti-diabetic agents in patients with heart failure.

Effects of a Dipeptidyl Peptidase 4 Inhibitor Sitagliptin on Glycemic Control and Lipoprotein Metabolism in Patients with Type 2 Diabetes Mellitus (GLORIA Trial)

Aim: The morbidity of cardiovascular disease in patients with type 2 diabetes mellitus (DM) deteriorates in combination with dyslipidemia. The accumulation of remnant lipoproteins in patients with fasting and postprandial hypertriglyceridemia is highly atherogenic. The current study investigated whether the dipeptidyl peptidase-4 inhibitor sitagliptin ameliorates dyslipidemia and hyperglycemia.

Methods: We enrolled 38 patients with type 2 DM (20 males and 18 females, 65.7 ± 9.9 years old, HbA1c levels < 8.4%), and all patients gave written informed consent. Sitagliptin (50 mg/day) was added to current antidiabetic treatments and increased to 100 mg/day to achieve low HbA1c levels (< 7.4%). Glucose and lipoprotein metabolism profiles were analyzed at 0, 4, and 12 weeks after sitagliptin administration.

Results: Sitagliptin significantly decreased fasting levels of triglyceride (TG) (161 ± 90 vs. 130 ± 66 mg/dl, p < 0.01) and non-HDL-C (129 ± 29 vs. 116 ± 20 mg/dl, p < 0.01) in combination with glucose (150 ± 47 vs. 129 ± 27 mg/dl, p < 0.01) and HbA1c (7.1 ± 0.6 vs. 6.6 ± 0.7 mg/dl, p < 0.001). Sitagliptin also significantly decreased the fasting levels of apolipoprotein (apo) B-48 (7.8 ± 6.7 vs. 5.6 ± 4.0 µg/ml, p < 0.01), remnant lipoprotein cholesterol (15.3 ± 9.5 vs. 12.0 ± 7.9 mg/dl, p < 0.05) and other apolipoproteins, such as apoB, apoC-II, apoC-III, and apoE. Analyses of the lipoprotein profiles of fasting sera revealed that sitagliptin significantly decreased cholesterol and TG levels of lipoprotein fractions in the size of very low density lipoprotein and low density lipoprotein.

Conclusions: These findings indicated that sitagliptin administration ameliorated the lipid and lipoprotein profiles in patients with diabetes, which may be due to the decrease in atherogenic remnant lipoproteins (UMIN#000013218).

Abbreviations:apo

apolipoprotein

ASCVD

atherosclerotic cardiovascular disease

CHD

coronary heart disease

CLEIA

chemiluminescence enzyme immunoassay

CM

Chylomicron

DPP-4

dipeptidyl peptidase-4

FFAs

free fatty acids

HPLC

high-performance liquid chromatography

IMT

intima-media thickness

LDL

low-density lipoprotein

LPL

lipoprotein lipase

PHTG

postprandial hypertriglyceridemia

RemL-C

remnant lipoprotein cholesterol

RLP-C

remnant-like particle cholesterol

TG

triglyceride

TRL

triglyceride-rich lipoprotein

VLDL

very low density lipoprotein

Sodium Glucose Cotransporter-2 Inhibition in Heart Failure: Potential Mechanisms, Clinical Applications, and Summary of Clinical Trials

Despite current established therapy, heart failure (HF) remains a leading cause of hospitalization and mortality worldwide. Novel therapeutic targets are therefore needed to improve the prognosis of patients with HF. The EMPA-REG OUTCOME trial ([Empagliflozin] Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients) demonstrated significant reductions in mortality and HF hospitalization risk in patients with type 2 diabetes mellitus (T2D) and cardiovascular disease with the antihyperglycemic agent, empagliflozin, a sodium glucose cotransporter 2 (SGLT2) inhibitor. The CANVAS trial (Canagliflozin Cardiovascular Assessment Study) subsequently reported a reduction in 3-point major adverse cardiovascular events and HF hospitalization risk. Although SGLT2 inhibition may have potential application beyond T2D, including HF, the mechanisms responsible for the cardioprotective effects of SGLT2 inhibitors remain incompletely understood. SGLT2 inhibition promotes natriuresis and osmotic diuresis, leading to plasma volume contraction and reduced preload, and decreases in blood pressure, arterial stiffness, and afterload as well, thereby improving subendocardial blood flow in patients with HF. SGLT2 inhibition is also associated with preservation of renal function. Based on data from mechanistic studies and clinical trials, large clinical trials with SGLT2 inhibitors are now investigating the potential use of SGLT2 inhibition in patients who have HF with and without T2D. Accordingly, in this review, we summarize the key pharmacodynamic effects of SGLT2 inhibitors and the clinical evidence that support the rationale for the use of SGLT2 inhibitors in patients with HF who have T2D. Because these favorable effects presumably occur independent of blood glucose lowering, we also explore the potential use of SGLT2 inhibition in patients without T2D with HF or at risk of HF, such as in patients with coronary artery disease or hypertension. Finally, we provide a detailed overview and summary of ongoing cardiovascular outcome trials with SGLT2 inhibitors.

Dipeptidyl peptidase-4 inhibitors and cancer risk in patients with type 2 diabetes: a meta-analysis of randomized clinical trials

Some recent studies have suggested that the use of dipeptidyl peptidase-4 inhibitors (DPP4i) is associated with cancer development. However, some other studies suggest no such association. The aim of the present study was to evaluate the effect of DPP4i on the risk of developing cancers. The electronic databases PubMed, Medline, EMBASE, Web of Science and Cochrane Library and the clinical trial registry were searched for published and unpublished randomized clinical trials on humans. Eligible studies were RCTs conducted in patients with type 2 diabetes mellitus, comparing DPP4i with a placebo or other active drugs. A total of 72 trials with 35,768 and 33,319 patients enrolled for DPP4i and the comparison drugs, respectively. Overall, no significant associations were detected between the use of DPP4i and cancer development, in comparison with the use of other active drugs or placebo. The results were consistent across pre-defined subgroups stratified by type of DPP4i, type of cancer, drug for comparison, trial duration, or baseline characteristics. The results of this meta-analysis suggest that patients with type 2 diabetes treated with DPP4i do not have a higher risk of developing cancers than patients treated with a placebo or other drugs.

The regulatory role of DPP4 in atherosclerotic disease

The increasing prevalence of atherosclerosis has become a worldwide health concern. Although significant progress has been made in the understanding of atherosclerosis pathogenesis, the underlying mechanisms are not fully understood. Recent studies suggest dipeptidyl peptidase-4 (DPP4), a regulator of inflammation and metabolism, may be involved in the development of atherosclerotic diseases. There has been increasing clinical and pre-clinical evidence showing DPP4-incretin axis is involved in cardiovascular disease. Although the cardiovascular outcome of DPP4 inhibition or incretin analogues has been or being evaluated by several large scale clinical trials, the exact role of DPP4 in atherosclerotic diseases is not completely understood. In the current review, we will summarize the recent advances in direct and indirect regulatory role of DPP4 in atherosclerosis.

Antidiabetic medications use trends in an Andalusian region from 2001 to 2014

PURPOSE

There is a widening range of antidiabetic medications available; however changes in consumption patterns remain poorly documented. The aim of this study is to analyze the evolution of consumption of antidiabetic medications during the period 2001-2014 in an Andalusian region.

METHODS

All antidiabetic medicines on the market were selected for analysis. Consumption data were obtained for the 15-year period and were expressed in defined daily doses (DDD) per 1000 inhabitants per day (DHD).

RESULTS

During the study period consumption of insulins grew only a 2.2%, from 17.9 DHD to 18.3 DHD, while oral agents increased a 27.6%, from 41.3 DHD to 52.7 DHD. Consumption of sulfonylureas was gradually reduced from 30.1 DHD to 16.4 DHD but metformin (alone) usage increased from 4.3 DHD to 23.7 DHD, and was the most consumed agent in 2014. A rise in consumption of dipeptidyl peptidase-4 inhibitors and "other hypoglycemic agents" was also noticed. Overall expenditure in antidiabetic medications increased notably from 4.5 in 2001 to 14.4 million euros in 2014.

CONCLUSION

We highlight the market uptake of antidiabetic drugs commercialized during the last decade; despite further exploration is needed to clarify the cost-benefit ratio of these new antidiabetic medicines.

Assessment of the Risk of Hospitalization for Heart Failure With Dipeptidyl Peptidase-4 Inhibitors, Saxagliptin, Alogliptin, and Sitagliptin in Patients With Type 2 Diabetes, Using an Alternative Measure to the Hazard Ratio

Background: Saxagliptin statistically significantly increased the risk of hospitalization for heart failure compared with placebo in the clinical trial of SAVOR-TIMI 53. Neither the reason why only saxagliptin among several dipeptidyl peptidase-4 (DPP-4) inhibitors increased the risk, nor the clinical implication of the result has been explained. Objective: To evaluate the risk of hospitalization for heart failure associated with DPP-4 inhibitors by using an alternative measure to the hazard ratio. Methods: We used the difference in restricted mean survival time (RMST) between DPP-4 inhibitors and placebo to evaluate the risk of cardiovascular events, including hospitalization for heart failure associated with DPP-4 inhibitors. Three randomized clinical trials with cardiovascular events as a primary end point—EXAMINE (alogliptin), SAVOR-TIMI 53 (saxagliptin), and TECOS (sitagliptin)—were reevaluated by estimating the RMSTs for the DPP-4 inhibitors and placebo based on the reconstructed individual patient data for each time-to-event outcome from publicly available information. Results: The differences of RMSTs (DPP-4 inhibitors minus placebo) for hospitalization for heart failure were −4 days [−6, −2] in the SAVOR-TIMI 53 (720 days follow-up), −3 days [−9, 3] in the EXAMINE (900 days follow-up), and 1 day [−5, 7] in the TECOS (1440 days follow-up). There were no substantial differences in the risk of other cardiovascular outcomes between DPP-4 inhibitors and placebo. Conclusions: There are no substantial clinically relevant differences in the risk of cardiovascular events, including hospitalization for heart failure, between 3 of the DPP-4 inhibitors and placebo.

High circulating plasma dipeptidyl peptidase- 4 levels in non-obese Asian Indians with type 2 diabetes correlate with fasting insulin and LDL-C levels, triceps skinfolds, total intra-abdominal adipose tissue volume and presence of diabetes: a case-control study

AIM

To evaluate circulating plasma dipeptidyl peptidase-4 (DPP4) levels in non-obese Asian Indians with type 2 diabetes mellitus (T2DM), and to correlate these with metabolic profile and measures of anthropometry, skinfolds, abdominal adipose tissue depots, pancreatic volume, and liver span.

METHODOLOGY

Non-obese (body mass index (BMI) <25 kg/m²) patients with T2DM (cases, n=93), diagnosed within 1 year from recruitment, on metformin therapy and BMI-matched, and non-diabetic subjects (controls, n=40) were compared. Measurements of blood glucose, glycosylated hemoglobin, plasma insulin levels, lipid profile, hepatic transaminases and plasma DPP4 levels, and quantification of abdominal fat depots, pancreatic volume and liver span (MRI scan), were done.

RESULTS

Significantly higher (p<0.001) circulating plasma DPP4 levels were observed in cases as compared to controls. Specifically, in patients with T2DM with non-alcoholic fatty liver disease (NAFLD) (n=48), the mean plasma DPP4 level (52.6±27.8 ng/mL) was significantly higher (p<0.05) as compared with those without NAFLD (n=43; 47±28.3 ng/mL). Significant positive correlation was observed for circulating plasma DPP4 levels with waist-to-hip ratio, total intra-abdominal adipose volume, and liver span. Fasting serum insulin, low-density lipoprotein cholesterol (LDL-C), triceps skinfolds, total intra-abdominal adipose tissue volume and presence of T2DM were significant determinants of circulating plasma DPP4 levels.

CONCLUSION

Non-obese Asian Indian patients with T2DM and on metformin therapy have significantly higher circulating plasma DPP4 levels as compared to non-obese non-diabetic controls, and these levels correlate with fasting insulin and LDL-C levels, upper limb subcutaneous adipose tissue, intra-abdominal adiposity and presence of diabetes.

Plasma DPP4 activity is associated with no-reflow and major bleeding events in Chinese PCI-treated STEMI patients

Dipeptidyl peptidase-4 (DPP4) is an important regulator of incretins and inflammation, and it is involved in the pathophysiological process of myocardial infarction (MI). This study investigated the role of plasma DPP4 activity (DPP4a) in patients with ST-segment elevation myocardial infarction (STEMI) who had undergone percutaneous coronary intervention (PCI). We recruited 747 consecutive PCI-treated STEMI patients from a tertiary referral center from January 2014 to October 2015. The outcomes of interest were the rates of no-reflow, in-hospital major adverse cardiac or cerebrovascular events (iMACCE), in-hospital complications (IHC) and in-hospital major bleeding. The DPP4a was lower in STEMI patients compared with the controls (p < 0.0001). Multivariate logistic-regression analyses (adjusted for confounding variables) showed that a 1 U/L increase in DPP4a was associated with an increased rate of no-reflow events (odds ratio [OR]: 1.07; 95% CI: 1.02-1.11; p < 0.01) and a decreased rate of major bleeding events (OR: 0.90; 95% CI: 0.82-0.98; p = 0.02). There were no associations between DPP4a and either iMACCE or IHC. In conclusions, high levels of DPP4a are independently associated with an increased rate of no-reflow events and a decreased rate of major bleeding events in PCT-treated STEMI patients.

Vildagliptin reduces plasma stromal cell-derived factor-1α in patients with type 2 diabetes compared with glimepiride

AIMS/INTRODUCTION

Dipeptidyl peptidase-4 inhibitors might have pleiotropic protective effects on cardiovascular disease (CVD), in contrast to sulfonylureas. Therefore, we compared various CVD risk factors between vildagliptin and glimepiride.

MATERIALS AND METHODS

We carried out a randomized, prospective and crossover trial. A total of 16 patients with type 2 diabetes whose glycated hemoglobin was >7% were randomized to add vildagliptin or glimepiride. After 12-week treatment, each drug was replaced with the other for another 12 weeks. Before and after each treatment, glucose homeostasis and CVD risk factors were assessed, and the continuous glucose monitoring system was applied to calculate glycemic variability.

RESULTS

The mean age of the participants was 60 years, 31% were men, body mass index 25.5 kg/m² and HbA1c 8.41%. Both vildagliptin and glimepiride significantly decreased glycated hemoglobin and glycemic variability indices. Despite the improved glucose homeostasis, favorable change of CVD markers was not prominent in both the arms, along with significant weight gain. Only plasma stromal cell-derived factor (SDF)-1α decreased by 30% in the vildagliptin arm. According to regression analyses, the reduction of SDF-1α was independently associated with vildagliptin usage and serum interleukin-6 changes, but white blood cells were not related with the SDF-1α changes.

CONCLUSION

Compared with glimepiride, vildagliptin arrestingly decreased plasma SDF-1α, and its clinical implications should be further investigated.

Transcriptomic alterations in the heart of non-obese type 2 diabetic Goto-Kakizaki rats

Background

There is a spectacular rise in the global prevalence of type 2 diabetes mellitus (T2DM) due to the worldwide obesity epidemic. However, a significant proportion of T2DM patients are non-obese and they also have an increased risk of cardiovascular diseases. As the Goto-Kakizaki (GK) rat is a well-known model of non-obese T2DM, the goal of this study was to investigate the effect of non-obese T2DM on cardiac alterations of the transcriptome in GK rats.

Methods

Fasting blood glucose, serum insulin and cholesterol levels were measured at 7, 11, and 15 weeks of age in male GK and control rats. Oral glucose tolerance test and pancreatic insulin level measurements were performed at 11 weeks of age. At week 15, total RNA was isolated from the myocardium and assayed by rat oligonucleotide microarray for 41,012 genes, and then expression of selected genes was confirmed by qRT-PCR. Gene ontology and protein–protein network analyses were performed to demonstrate potentially characteristic gene alterations and key genes in non-obese T2DM.

Results

Fasting blood glucose, serum insulin and cholesterol levels were significantly increased, glucose tolerance and insulin sensitivity were significantly impaired in GK rats as compared to controls. In hearts of GK rats, 204 genes showed significant up-regulation and 303 genes showed down-regulation as compared to controls according to microarray analysis. Genes with significantly altered expression in the heart due to non-obese T2DM includes functional clusters of metabolism (e.g. Cyp2e1, Akr1b10), signal transduction (e.g. Dpp4, Stat3), receptors and ion channels (e.g. Sln, Chrng), membrane and structural proteins (e.g. Tnni1, Mylk2, Col8a1, Adam33), cell growth and differentiation (e.g. Gpc3, Jund), immune response (e.g. C3, C4a), and others (e.g. Lrp8, Msln, Klkc1, Epn3). Gene ontology analysis revealed several significantly enriched functional inter-relationships between genes influenced by non-obese T2DM. Protein–protein interaction analysis demonstrated that Stat is a potential key gene influenced by non-obese T2DM.

Conclusions

Non-obese T2DM alters cardiac gene expression profile. The altered genes may be involved in the development of cardiac pathologies and could be potential therapeutic targets in non-obese T2DM.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-016-0424-3) contains supplementary material, which is available to authorized users.

Sitagliptin and risk of heart failure hospitalization in patients with type 2 diabetes on dialysis: A population-based cohort study

The incidence of heart failure hospitalization (HHF) after taking sitagliptin in type 2 diabetes (T2DM) patients with end stage renal disease (ESRD) on dialysis is unclear. In this population-based cohort study, we identified individuals with T2DM and ESRD on dialysis who were treated with sitagliptin between 2009 and 2011 and randomly selected a control cohort matched by age, sex, duration of T2DM, hypertension medications, use of statin and aspirin, sulfonylureas, glinides, and insulin usage, atherosclerotic heart disease, congestive heart failure and chronic obstructive pulmonary disease at a 1:4 ratio. Multivariable Cox proportional hazards regression analysis was used to evaluate HHF risk. The overall incidence of HHF was higher in the sitagliptin cohort than in the control cohort (1130 vs. 754 per 10000 person-years; adjusted hazard ratio (HR): 1.52, 95% CI = 1.21–1.90). There was a significant trend towards increased HHF risk associated with increased sitagliptin dose (p for trend < 0.01). Subjects at greater risk of HHF after taking sitagliptin were those without severe hypoglycemia, without ACE inhibitors treatment, with history of heart failure or receiving hemodialysis rather than peritoneal dialysis. In conclusion, use of sitagliptin was associated with an increased risk of HHF in patients with T2DM on dialysis.

Cardiovascular efficacy of sitagliptin in patients with diabetes at high risk of cardiovascular disease: a 12-month follow-up

BACKGROUND

Gliptins should have beneficial effects beyond glycemic control, potentially on the pathophysiology of cardiovascular (CV) diseases, with some basic studies demonstrating this possibility. However, we are yet to answer whether there are any direct CV effects in the clinical setting. We aimed to examine the beneficial effects of sitagliptin in Japanese patients with diabetes and high CV risk for 12 months.

METHODS

This was a prospective, multicenter, observational study of 205 patients with type 2 diabetes. All participants had more than one major CV risk factor and were treated with sitagliptin for 12 months. At 3 or 12 months, we examined the effects of treatment on glycemic control, CV function (by electrocardiography, echocardiography, and reactive hyperemia-peripheral arterial tonometry), and CV biomarkers.

RESULTS

Patients were predominantly elderly (68.8 ± 9.9 years) and male (71.5 %) and typically had more than three CV risk factors (79.2 %). Treatment with sitagliptin significantly reduced the hemoglobin A1c (HbA1c) level from 7.09 % ± 0.81 % at baseline to 6.67 % ± 0.69 % at 3 months and 6.68 % ± 0.73 % at 12 months (both P < 0.001). The reduction in HbA1c was also in tandem with the decrease in the level of high-sensitive C-reactive protein throughout the study. Independent of the change in HbA1c, sitagliptin reduced systolic (-7.0 ± 18.9 mmHg) and diastolic blood pressure (-5.1 ± 11.7 mmHg) at 12 months, and this was associated with a decrease in urinary albumin. In contrast, there were no beneficial effects on cardiac and endothelial function or on the levels of serum B-type natriuretic peptide, high-sensitive troponin T, and urinary 8-hydroxy-2'-deoxyguanosine.

CONCLUSIONS

In Japanese patients with diabetes and multiple CV risk factors, sitagliptin showed a decrease in blood pressure associated with an improvement in albuminuria in addition to glycemic control.

TRIAL REGISTRATION

UMIN000005663.