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

Taiwan Association for the Study of the Liver-Taiwan Society of Cardiology Taiwan position statement for the management of metabolic dysfunction- associated fatty liver disease and cardiovascular diseases

Metabolic dysfunction-associated fatty liver disease (MAFLD) is an increasingly common liver disease worldwide. MAFLD is diagnosed based on the presence of steatosis on images, histological findings, or serum marker levels as well as the presence of at least one of the three metabolic features: overweight/obesity, type 2 diabetes mellitus, and metabolic risk factors. MAFLD is not only a liver disease but also a factor contributing to or related to cardiovascular diseases (CVD), which is the major etiology responsible for morbidity and mortality in patients with MAFLD. Hence, understanding the association between MAFLD and CVD, surveillance and risk stratification of MAFLD in patients with CVD, and assessment of the current status of MAFLD management are urgent requirements for both hepatologists and cardiologists. This Taiwan position statement reviews the literature and provides suggestions regarding the epidemiology, etiology, risk factors, risk stratification, nonpharmacological interventions, and potential drug treatments of MAFLD, focusing on its association with CVD.

Long-term efficacy and safety of early alogliptin initiation in subjects with type 2 diabetes: an extension of the SPEAD-A study

We previously reported in the study of preventive effects of alogliptin on diabetic atherosclerosis (SPEAD-A) that alogliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, attenuated the progression of carotid atherosclerosis in subjects with type 2 diabetes and no history of cardiovascular disease. This extension study of the SPEAD-A trial investigated whether early alogliptin initiation improved long-term cardiovascular outcomes. The SPEAD-A trial randomized 341 subjects with type 2 diabetes to either alogliptin or conventional treatment to investigate the effects of alogliptin on atherosclerosis. All subjects who completed that trial were eligible for this prospective, observational cohort study. The primary endpoint was the first occurrence of a major cardiovascular event, defined as death due to any cause, acute myocardial infarction, or stroke. During the 520-week follow-up period, composite primary outcome events occurred in only a few subjects in each group [8 (5.4%) in the alogliptin group and 9 in the conventional treatment group (5.9%)]. There were no significant differences in the incidence rate of the primary outcome between the two groups. Post hoc Poisson regression analysis showed no significant difference between the two groups in the incidence rate of composite recurrence events for the same outcomes as the primary endpoint. On the other hand, this incidence rate was significantly lower in subjects who received DPP-4 inhibitors before an initial cardiovascular event than in those who did not (5.8 vs. 13.3 per 1000 person-years, respectively, p = 0.04). Early initiation of alogliptin was not associated with a reduced risk of composite cardiovascular disease, which could be attributed to fewer events and/or the addition of DPP-4 inhibitors during the follow-up period.

The effects of using Tempeh as a supplement for type 2 diabetes

Studies suggest that the consumption of Tempeh can improve abnormal blood glucose and lipid parameters, although it remains still unclear as to whether Tempeh can improve tissue damage. In our study, db/db obese diabetic mice were given Tempeh 1 (300 mg/kg) and Tempeh 2 (600 mg/kg) for 3 months. The tissue samples collected were stained using different tissue-staining methodologies and were compared with the diabetic control group that was not given any Tempeh. Our results demonstrated that consuming high-dose Tempeh for 1 month could significantly reduce serum glucose and body weight in mice whereas the tissue section of our result could validate that consuming high-dose Tempeh for 3 months effectively improves lipid droplet size and lipid accumulation in the liver, aorta, and kidney of the mice. Moreover, an indication of the recovery of the damaged tissue could be observed in the heart and pancreatic tissue when high dosage of Tempeh was given as a treatment. Thus, it can be concluded that continuous consumption of Tempeh as a treatment could improve both blood glucose and body weight of diabetic mice while also improving lipid accumulation and tissue damage.

Inflammation and atherosclerosis: signaling pathways and therapeutic intervention

Atherosclerosis is a chronic inflammatory vascular disease driven by traditional and nontraditional risk factors. Genome-wide association combined with clonal lineage tracing and clinical trials have demonstrated that innate and adaptive immune responses can promote or quell atherosclerosis. Several signaling pathways, that are associated with the inflammatory response, have been implicated within atherosclerosis such as NLRP3 inflammasome, toll-like receptors, proprotein convertase subtilisin/kexin type 9, Notch and Wnt signaling pathways, which are of importance for atherosclerosis development and regression. Targeting inflammatory pathways, especially the NLRP3 inflammasome pathway and its regulated inflammatory cytokine interleukin-1β, could represent an attractive new route for the treatment of atherosclerotic diseases. Herein, we summarize the knowledge on cellular participants and key inflammatory signaling pathways in atherosclerosis, and discuss the preclinical studies targeting these key pathways for atherosclerosis, the clinical trials that are going to target some of these processes, and the effects of quelling inflammation and atherosclerosis in the clinic.

Significance of Glycemic Variability in Diabetes Mellitus

The goal of diabetes treatment is to maintain good glycemic control, prevent the development and progression of diabetic complications, and ensure the same quality of life and life expectancy as healthy people. Hemoglobin A1c (HbA1c) is used as an index of glycemic control, but strict glycemic control using HbA1c as an index may lead to severe hypoglycemia and cardiovascular death. Glycemic variability (GV), such as excessive hyperglycemia and hypoglycemia, is associated with diabetic vascular complications and has been recognized as an important index of glycemic control. Here, we reviewed the definition and evaluated the clinical usefulness of GV, and its relationship with diabetic complications and therapeutic strategies to reduce GV.

Sitagliptin protects renal glomerular endothelial cells against high glucose-induced dysfunction and injury

Sitagliptin is a well-established anti-diabetic drug that also exerts protective effects on diabetic complications. Previous work reveals that sitagliptin has a protective effect on diabetic nephropathy (DN). Vascular impairment frequently occurs in diabetic renal complications. Here, we evaluated the protective function of sitagliptin in human renal glomerular endothelial cells (HrGECs) under high glucose (HG) conditions. Expressions of the pro-inflammatory cytokines interleukin-1β (IL-1β) and interleukin-8 (IL-8) were assessed using real-time PCR and ELISA. Endothelial cells permeability was assayed using the fluorescein isothiocyanate dextran (FITC-dextran) and trans-endothelial electrical resistance (TEER) assay. The results show that sitagliptin mitigated HG-induced oxidative stress in HrGECs with decreased levels of mitochondrial reactive oxygen species (ROS), Malondialdehyde (MDA), and 8-hydroxydeoxyguanosine (8-OHdG). Sitagliptin inhibited HG-induced production of pro-inflammatory cytokines interleukin-1β (IL-1β) and interleukin-8 (IL-8) in HrGECs. It also ameliorated HG-induced aggravation of HrGECs permeability and reduction of the tight junction component claudin-5. Moreover, kruppel Like Factor 6 (KLF6) mediated the protective effects of sitagliptin on endothelial monolayer permeability against HG. Collectively, sitagliptin reversed the HG-induced oxidative stress, inflammation, and increased permeability in HrGECs via regulating KLF6. This study suggests that sitagliptin might be implicated as an effective strategy for preventing diabetic renal injuries in the future.

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.

Cardioprotective Effect of Quercetin and Sitagliptin in Doxorubicin-Induced Cardiac Toxicity in Rats

Objective

A previous study revealed a pronounced protective effect of combining quercetin (QC) with sitagliptin (STN) in testicular tissue. Accordingly, this study was designed to evaluate the cardioprotective effects of QC and STN each alone or in combination in doxorubicin (DOX)-induced cardiotoxicity in the rats.

Methodology

Thirty male adult Wistar rats were divided into five groups: the first group (control) treated with sodium chloride, the second group treated with DOX (3 mg/kg I.P. injection), the third group treated with DOX with a combination of QC (80 mg/kg), and STN (10 mg/kg), the fourth group treated with DOX and QC and the fifth group treated with DOX and STN. Blood was collected on day 22 and used for assessment of serum troponin, lactate dehydrogenase (LDH), creatine phosphokinase (CPK), total lipid profile, C-reactive protein (CRP), and total antioxidant capacity (TAOC). Atherogenic indices were also calculated. Cardiac tissue was sent for histopathological analysis.

Results

DOX produced a significant increase in the level of troponin, LDH, CKP, CRP, total cholesterol (TC), low-density lipoprotein (LDL), triglycerides (TG), and atherogenic index of plasma; and significantly decreased TAOC. The combination of quercetin and sitagliptin was more effective than each treatment alone in restoring the level of troponin, LDH, CKP, CRP, Cholesterol, LDL, TG, atherogenic index of plasma and significantly increased TAOC compared to DOX treated group. The histopathological finding also supports the biochemical results.

Conclusion

The study revealed the cardioprotective effects of the combination of QC and STN which could be attributed to the additive effects of this combination through antioxidant, anti-inflammatory, lipid lowering and anti-atherogenic activities; suggesting it as a good therapeutic candidate to be tested in the clinical setting.

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.

Curcumin protects cardiomyopathy damage through inhibiting the production of reactive oxygen species in type 2 diabetic mice

Type 2 diabetes mellitus (DM)-induced cardiomyopathy is a multifactorial and complex disease involving oxidative stress, lipids, and fibrosis. It is based on metabolic disorders and microvascular disease and causes extensive focal necrosis of the heart muscle. Curcumin (CUR) is a natural polyphenol isolated from turmeric rhizomes and plays an important role in the antioxidant, anti-apoptotic and anti-inflammatory effects of diabetes. Therefore, we established a mouse model of diabetic cardiomyopathy (DCM) in type 2 diabetic db/db mice in our study. We divided the experiment into three groups: the control group, DM group and DM + CUR group.We performed cardiac dissection on mice treated in different conditions and conducted special pathological staining on isolated cardiac tissue. We were surprised to find that a high glucose environment can promote cardiomyocyte apoptosis by TUNEL assay. In addition, after detecting dihydroethiidine (DHE), hematoxylin-eosin (H&E) and Oil Red O staining, we unexpectedly found that CUR can inhibit the production of reactive oxygen species (ROS), reduce myocardial apoptosis, and myocardial lipid accumulation. CUR upregulated the expression of Bcl-2, and downstream the expression of Bax and Caspase-3 proteins by immunohistochemical determination and western blotting. Therefore, these results suggest that CUR has a certain protective effect on diabetic cardiomyopathy by inhibiting the production of ROS.

A Dipeptidyl Peptidase-4 Inhibitor Inhibits Foam Cell Formation of Macrophages in Type 1 Diabetes via Suppression of CD36 and ACAT-1 Expression

Dipeptidyl peptidase-4 (DPP-4) inhibitors have been reported to play a protective role against atherosclerosis in both animal models and patients with type 2 diabetes (T2D). However, since T2D is associated with dyslipidemia, hypertension and insulin resistance, part of which are ameliorated by DPP-4 inhibitors, it remains unclear whether DPP-4 inhibitors could have anti-atherosclerotic properties directly by attenuating the harmful effects of hyperglycemia. Therefore, we examined whether a DPP-4 inhibitor, teneligliptin, could suppress oxidized low-density lipoprotein (ox-LDL) uptake, foam cell formation, CD36 and acyl-coenzyme A: cholesterol acyltransferase-1 (ACAT-1) gene expression of macrophages isolated from streptozotocin-induced type 1 diabetes (T1D) mice and T1D patients as well as advanced glycation end product (AGE)-exposed mouse peritoneal macrophages and THP-1 cells. Foam cell formation, CD36 and ACAT-1 gene expression of macrophages derived from T1D mice or patients increased compared with those from non-diabetic controls, all of which were inhibited by 10 nmol/L teneligliptin. AGEs mimicked the effects of T1D; teneligliptin attenuated all the deleterious effects of AGEs in mouse macrophages and THP-1 cells. Our present findings suggest that teneligliptin may inhibit foam cell formation of macrophages in T1D via suppression of CD36 and ACAT-1 gene expression partly by attenuating the harmful effects of AGEs.

2020 Consensus of Taiwan Society of Cardiology on the pharmacological management of patients with type 2 diabetes and cardiovascular diseases

The global incidence and prevalence of type 2 diabetes have been escalating in recent decades. The total diabetic population is expected to increase from 415 million in 2015 to 642 million by 2040. Patients with type 2 diabetes have an increased risk of atherosclerotic cardiovascular disease (ASCVD). About two-thirds of patients with type 2 diabetes died of ASCVD. The association between hyperglycemia and elevated cardiovascular (CV) risk has been demonstrated in multiple cohort studies. However, clinical trials of intensive glucose reduction by conventional antidiabetic agents did not significantly reduce macrovascular outcomes.In December 2008, U.S. Food and Drug Administration issued a mandate that every new antidiabetic agent requires rigorous assessments of its CV safety. Thereafter, more than 200,000 patients have been enrolled in a number of randomized controlled trials (RCTs). These trials were initially designed to prove noninferiority. It turned out that some of these trials demonstrated superiority of some new antidiabetic agents versus placebo in reducing CV endpoints, including macrovascular events, renal events, and heart failure. These results are important in clinical practice and also provide an opportunity for academic society to formulate treatment guidelines or consensus to provide specific recommendations for glucose control in various CV diseases.In 2018, the Taiwan Society of Cardiology (TSOC) and the Diabetes Association of Republic of China (DAROC) published the first joint consensus on the "Pharmacological Management of Patients with Type 2 Diabetes and Cardiovascular Diseases." In 2020, TSOC appointed a new consensus group to revise the previous version. The updated 2020 consensus was comprised of 5 major parts: (1) treatment of diabetes in patients with multiple risk factors, (2) treatment of diabetes in patients with coronary heart disease, (3) treatment of diabetes in patients with stage 3 chronic kidney disease, (4) treatment of diabetes in patients with a history of stroke, and (5) treatment of diabetes in patients with heart failure. The members of the consensus group thoroughly reviewed all the evidence, mainly RCTs, and also included meta-analyses and real-world evidence. The treatment targets of HbA1c were finalized. The antidiabetic agents were ranked according to their clinical evidence. The consensus is not mandatory. The final decision may need to be individualized and based on clinicians' discretion.

The efficacy and safety of luseogliflozin and sitagliptin depending on the sequence of administration in patients with type 2 diabetes mellitus: a randomized controlled pilot study

Background: The efficacy and safety of SGLT-2 and DPP-4 inhibitor monotherapies in T2DM is well established; however, data on the effect of combination therapies and sequence of administration are lacking. We investigated the efficacy and safety of the sequence of SGLT-2 and DPP-4 inhibitor administration in Japanese T2DM patients.Research design and methods: In this single-institution, open-label, randomized controlled study, T2DM patients inadequately controlled (HbA1c ≥6.5%) with conventional therapy were randomized to receive luseogliflozin-sitagliptin (LS; luseogliflozin 2.5 mg for 0-12 weeks, then luseogliflozin plus sitagliptin 50 mg for 12-24 weeks) or sitagliptin-luseogliflozin (SL; sitagliptin 50 mg for 0-12 weeks, then sitagliptin plus luseogliflozin 2.5 mg for 12-24 weeks). The main outcome was the difference in mean change in HbA1c at 24 weeks relative to baseline between both groups.Results: Of the 41 enrolled and randomized patients, 34 completed the study. Mean ± SD HbA1c at baseline was 10.35 ± 1.04% and 10.02 ± 1.40% in the LS and SL groups, respectively, and mean ± SD change in HbA1c at 24 weeks from baseline was -3.81 ± 1.21% vs -2.46 ± 1.42% (P < 0.01), respectively. No drug-related adverse events were reported.Conclusion: Over the 24-week period, LS was more effective in reducing HbA1c levels than SL in Japanese T2DM patients.

Risk of cardiovascular events associated with dipeptidyl peptidase-4 inhibitors in patients with diabetes with and without chronic kidney disease: A nationwide cohort study

BACKGROUND

Cardiovascular events associated with oral hypoglycemic agents (OHAs) have raised significant safety concerns. This study assessed the association between dipeptidyl peptidase-4 inhibitors (DPP-4i) and the risk of cardiovascular events in patients with type 2 diabetes mellitus with or without chronic kidney disease (CKD).

STUDY DESIGN

A retrospective cohort study using Taiwan's National Health Insurance Research Database.

SETTINGS AND PARTICIPANTS

Our study included patients with type 2 diabetes who received OHAs between March 1, 2009, and December 31, 2012. All eligible subjects were classified into CKD and non-CKD cohorts and further categorized as the DPP-4i and non-DPP-4i users in each cohort.

METHODS

The DPP-4i and non-DPP-4i groups were matched 1:1 by propensity score to attenuate potential selection bias. Propensity score was estimated by logistic regression, using demographics, co-medications, comorbidities. and adapted diabetic complication severity index at baseline.

OUTCOMES

Outcomes of interest included a composite endpoint of ischemic stroke, myocardial infarction, cardiovascular death (major adverse cardiac events [MACE]), and hospitalization for heart failure (hHF). COX proportional hazard models were applied to examine the association between DPP-4i and outcomes of interest.

RESULTS

We identified 37,641 and 87,604 patients with type 2 diabetes with and without CKD, respectively. After propensity score matching, 8,213 pairs of CKD patients and 12,313 pairs of non-CKD patients were included for analysis. In the CKD cohort, DPP-4i were associated with a 25% increased risk of hHF (DPP-4i vs. non-DPP-4i incidence/1,000 person-years: 15.0 vs. 9.9, HR = 1.25; 95% CI 1.01-1.54, p = 0.037) but not with the risk of MACE (HR = 0.89, p = 0.144). In the non-CKD cohort, DPP-4i were associated with a lower risk of MACE (DPP-4i vs. non-DPP-4i incidence/1,000 person-years: 9.8 vs. 12.6 HR = 0.73; 95% CI 0.61-0.87, p = 0.0007), but not the risk of hHF (HR = 1.09, p = 0.631).

CONCLUSIONS

DPP-4i were found to be associated with decreased risk of MACE in the non-CKD cohort in our study. However, DPP-4i were associated with increased risk of hHF in the CKD cohort. DPP-4i in the CKD cohort should be used cautiously.

Rationale and design of study of dapagliflozin versus sitagliptin treatment efficacy on prevention of cardiovascular risk factors in type 2 diabetes patients: the DIVERSITY-CVR study

BACKGROUND

Recent studies reported that sodium glucose cotransporter 2 (SGLT2) inhibitors reduced the cardiovascular morbidity and mortality in patients with type 2 diabetes mellitus (T2DM) compared to placebo in contrast to no reduction with dipeptidyl peptidase 4 (DPP4) inhibitors. However, there are no comparative studies on the effects of SGLT2 inhibitors and DPP4 inhibitors on HbA1c, body weight and hypoglycemia as risk factors of cardiovascular diseases. The aim of the present ongoing study is to compare the effects of dapagliflozin, a SGLT2 inhibitor, with those of sitagliptin, a DPP4 inhibitor, on cardiovascular risk factors in T2DM patients with inadequate glycemic control.

METHODS

The study of dapagliflozin versus sitagliptin treatment efficacy on prevention of cardiovascular risk factors in T2DM patients (DIVERSITY-CVR study) is a prospective, randomized, open-label, blinded-endpoint, parallel-group, comparative study. A total of 340 T2DM patients treated with metformin alone or with no glucose-lowering agents (hemoglobin A1c ≥ 7.0 and < 10.0%) will be randomized into the dapagliflozin group (5-10 mg/day, n = 170) and the sitagliptin group (50-100 mg/day, n = 170), and treated for 24 weeks. The primary endpoint is the rate of achieving a composite endpoint of the following three items at 24th week; (1) HbA1c < 7.0%; (2) body weight loss of ≥ 3.0% from baseline; (3) avoidance of hypoglycemia. Hypoglycemia will be monitored using the flash glucose monitoring system. The secondary outcomes include each component of the primary endpoint, plus indices of lipid metabolism, and evaluations related to safety.

CONCLUSIONS

There is lack of solid information on differences in the therapeutic effects of SGLT2 inhibitors and DPP4 inhibitors on multiple risk factors for cardiovascular diseases. It is anticipated that the results of the DIVERSITY-CVR study provides useful clinical data on the management of patients with T2DM, including reducing the risk of CVD. The results of this study will become available in 2019. Trial registration University Hospital Medical Information Network Clinical Trial Registry (UMIN000028014). Registered 30 June 2017.

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.

Dipeptidyl peptidase-4 inhibitor decreases the risk of atrial fibrillation in patients with type 2 diabetes: a nationwide cohort study in Taiwan

BACKGROUND

Whether dipeptidyl peptidase-4 inhibitor (DPP4i) is associated with a lower risk of new-onset atrial fibrillation (AF) in patients with diabetes remains unclear. This study aimed to evaluate the risk of AF associated with use of DPP4i among a longitudinal cohort of patients with diabetes.

METHODS

Over a 3-year period, 480,000 patients with diabetes were analyzed utilizing Taiwan's National Health Insurance Research Database and 90,880 patients taking metformin as first-line therapy were enrolled. Patients were further divided into two groups: (1) DPP4i users: those taking DPP4i and (2) non-DPP4i users: those prescribed other hypoglycemic agents (HAs) as second-line drug. Study end point was defined by diagnosis of AF, addition of any third-line HA, or the end of the study period (December 31, 2013), whichever came first.

RESULTS

A total of 16,017 DPP4i users and 74,863 non-DPP4i users were eligible for the study. For the DPP4i group, most patients were prescribed sitagliptin (n = 12,180; 76%). Among the non-DPP4i group, most patients took sulfonylurea (n = 60,606; 81%) as their second-line medication. DPP4i users were associated with a lower risk of new-onset AF compared with non-DPP4i users after propensity-score weighting (hazard ratio 0.65; P < 0.0001). Subgroup analysis showed that DPP4i user were associated with a lower risk of new-onset AF compared with non-DPP4i users in most subgroups. Multivariate analysis indicated that use of DPP4i was associated with lower risk of new-onset AF and age > 65 years, presence of hypertension, and ischemic heart disease were independent risk factors for new-onset AF.

CONCLUSIONS

Among patients with diabetes prescribed with metformin, the patients with DPP4i as second HA were associated with a lower risk of AF compared with the patients with other drugs as second HAs in real-world practice.

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

Dipeptidyl Peptidase-4 Inhibitor–Associated Risk of Bleeding: An Evaluation of Reported Adverse Events

Background: Dipeptidyl peptidase-4 (DPP-4) inhibitors improve glycemic control, and sitagliptin has been associated with a reduction in cardiovascular events. In vivo data suggest reduced platelet activation, and aggregation may play a role, and therefore, increased bleeding risk is possible. Objective: Comparatively assess bleeding risks associated with DPP-4 inhibitors against standard treatment. Methods: Exploratory analyses of adverse event reports (AERs) from the US Food and Drug Administration Adverse Event Reporting System (FAERS) database (2004-2012 periods) were conducted. DPP-4 inhibitor–related bleeding was assessed with metformin as negative control, and aspirin, clopidogrel, and prasugrel illustrated positive comparators. Reporting odds ratios (RORs) and 95% CIs were calculated as a measure of disproportionality of reporting, and RORs were compared across drugs with the Breslow-Day statistics. Results: From 2004 to 2012, 36 298, 4288, and 1202 AERs were found for sitagliptin, saxagliptin, and linagliptin, respectively, with 863, 102, and 14 bleeding complications. The relative reporting rate was not elevated with any DPP-4 inhibitor (sitagliptin: ROR = 0.71, 95% CI = 0.67-0.76; saxagliptin: ROR = 0.72, 95% CI = 0.59-0.87; linagliptin: ROR = 0.35, 95% CI = 0.20-0.59) or with metformin (ROR = 0.77; 95% CI = 0.75-0.78). Sitagliptin showed relatively higher reporting as compared with linagliptin ( P = 0.006) but not with saxagliptin ( P = 0.98). As positive references, antiplatelet drugs demonstrated relatively higher reporting compared with metformin (aspirin: ROR = 1.50, 95% CI = 1.48-1.51; clopidogrel: ROR = 2.28, 95% CI = 2.23-2.33; prasugrel: ROR = 5.09, 95% CI = 4.57-5.67). Conclusion: DPP-4 inhibitors were not associated with an undue increase in bleeding AERs in the FAERS database.

DPP-4 inhibitors in diabetic complications: role of DPP-4 beyond glucose control

Dipeptidyl peptidase-4 (DPP-4) inhibitors (gliptins) are an emerging class of antidiabetic drugs that constitutes approximately fifty percent of the market share of the oral hypoglycemic drugs. Its mechanism of action for lowering blood glucose is essentially via inhibition of the rapid degradation of incretin hormones, such as glucagon-like peptide (GLP)-1 and gastric inhibitory polypeptide (GIP), thus the plasma concentration of GLP-1 increases, which promotes insulin secretion from the pancreatic β cells and suppresses glucagon secretion from the α cells. In addition to the direct actions on the pancreas, GLP-1 exhibits diverse actions on different tissues through its action on GLP-1 receptor, which is expressed ubiquitously. Moreover, DPP-4 has multiple substrates besides GLP-1 and GIP, including cytokines, chemokines, neuropeptides, and growth factors, which are involved in many pathophysiological conditions. Recently, it was suggested that DPP-4 is a new adipokine secreted from the adipose tissue, which plays an important role in the regulation of the endocrine function in obesity-associated type 2 diabetes. Consequently, DPP-4 inhibitors have been reported to exhibit cytoprotective functions against various diabetic complications affecting the liver, heart, kidneys, retina, and neurons. This review outlines the current understanding of the effect of DPP-4 inhibitors on the complications associated with type 2 diabetes, such as liver steatosis and inflammation, dysfunction of the adipose tissue and pancreas, cardiovascular diseases, nephropathy, and neuropathy in preclinical and clinical studies.