Cardiovascular risks associated with second-line oral antidiabetic agents added to metformin in patients with Type 2 diabetes: a nationwide cohort study

Cardiovascular risk reduction in older people with type 2 diabetes mellitus-a comprehensive narrative review

Metabolic targets are controversial in older people with type 2 diabetes due to functional heterogeneity and morbidity burden. Tight blood pressure and metabolic control appears beneficial in fit individuals who are newly diagnosed with type 2 diabetes and have fewer comorbidities. The benefits of low blood pressure and tight metabolic control is attenuated with the development of comorbidities, especially frailty. Guidelines consider frail older people as one category and recommend relaxed targets. However, sarcopenic obese frail individuals may benefit from tight targets and intensification of therapy due to their unfavourable metabolic profile, accelerated diabetes trajectory and high cardiovascular risk. In addition, the early use of sodium glucose transporter-2 inhibitors and glucagon like peptide-1 receptor agonists may be beneficial in this frailty phenotype due to their cardio-renal protection, which is independent of glycaemic control, provided they are able to engage in resistance exercise training to avoid loss of muscle mass. In the anorexic malnourished frail individual, early use of insulin, due to its weight gain and anabolic properties, is appropriate. In this phenotype, targets should be relaxed with deintensification of therapy due to significant weight loss, decelerated diabetes trajectory and increased risk of medication side effects.

Vitamin B12-Induced Autophagy Alleviates High Glucose-Mediated Apoptosis of Islet β Cells

High glucose levels can lead to the apoptosis of islet β cells, while autophagy can provide cytoprotection and promote autophagic cell death. Vitamin B12, a water-soluble B vitamin, has been shown to regulate insulin secretion and increase insulin sensitivity. However, the precise mechanism of action remains unclear. In this study, we investigated the influence of vitamin B12 on high glucose-induced apoptosis and autophagy in RIN-m5F cells to elucidate how vitamin B12 modulates insulin release. Our results demonstrate that exposure to 45 mM glucose led to a significant increase in the apoptosis rate of RIN-m5F cells. The treatment with vitamin B12 reduced the apoptosis rate and increased the number of autophagosomes. Moreover, vitamin B12 increased the ratio of microtubule-associated protein 1 light chain 3 beta to microtubule-associated protein 1 light chain 3 alpha (LC3-II/LC3-I), while decreasing the amount of sequestosome 1 (p62) and inhibiting the phosphorylation of p70 ribosomal protein S6 kinase (p70S6K) under both normal- and high-glucose conditions. The additional experiments revealed that vitamin B12 inhibited high glucose-induced apoptosis. Notably, this protective effect was attenuated when the autophagy inhibitor 3-methyladenine was introduced. Our findings suggest that vitamin B12 protects islet β cells against apoptosis induced by high glucose levels, possibly by inducing autophagy.

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.

Hypoglycaemic therapy in frail older people with type 2 diabetes mellitus-a choice determined by metabolic phenotype

Frailty is a newly emerging complication of diabetes in older people and increasingly recognised in national and international clinical guidelines. However, frailty remains less clearly defined and frail older people with diabetes are rarely characterised. The general recommendation of clinical guidelines is to aim for a relaxed glycaemic control, mainly to avoid hypoglycaemia, in this often-vulnerable group of patients. With increasing age and development of frailty, body composition changes are characterised by an increase in visceral adipose tissue and a decrease in body muscle mass. Depending on the overall body weight, differential loss of muscle fibre types and body adipose/muscle tissue ratio, the presence of any associated frailty can be seen as a spectrum of metabolic phenotypes that vary in insulin resistance of which we have defined two specific phenotypes. The sarcopenic obese (SO) frail phenotype with increased visceral fat and increased insulin resistance on one side of spectrum and the anorexic malnourished (AM) frail phenotype with significant muscle loss and reduced insulin resistance on the other. In view of these varying metabolic phenotypes, the choice of hypoglycaemic therapy, glycaemic targets and overall goals of therapy are likely to be different. In the SO phenotype, weight-limiting hypoglycaemic agents, especially the new agents of GLP-1RA and SGLT-2 inhibitors, should be considered early on in therapy due to their benefits on weight reduction and ability to achieve tight glycaemic control where the focus will be on the reduction of cardiovascular risk. In the AM phenotype, weight-neutral agents or insulin therapy should be considered early on due to their benefits of limiting further weight loss and the possible anabolic effects of insulin. Here, the goals of therapy will be a combination of relaxed glycaemic control and avoidance of hypoglycaemia; and the focus will be on maintenance of a good quality of life. Future research is still required to develop novel hypoglycaemic agents with a positive effect on body composition in frailty and improvements in clinical outcomes.

Outcomes of second-line oral antidiabetic drugs in persons with young-onset type 2 diabetes

AIM

People with young-onset diabetes (YOD) exhibit a higher risk of morbidity and mortality than those with late-onset diabetes. Few studies have explored the preferred management of diabetes in such patients. We compared the risks of hospitalization and mortality among people with YOD to whom second-line oral antidiabetic drugs (OADs) were administered.

METHODS

7257 people taking second-line OADs after initial metformin therapy were enrolled during 2009-2014. Using add-on sulfonylureas (SUs) as a reference, the multivariable Cox regression model was used to compare the hospitalization and mortality risks among 5 categories of second-line OADs: alpha-glucosidase inhibitors, meglitinide, dipeptidyl peptidase-4 (DPP-4) inhibitors, SUs, and thiazolidinediones.

RESULTS

After baseline characteristics, comorbidities, duration of diabetes, and drug use were controlled, the adjusted hazard ratios and 95% confidence interval for all-cause, cardiovascular, and non-infection hospitalization and all-cause mortality for metformin plus DPP-4 inhibitors were 0.62 (0.52-0.73), 0.49 (0.29-0.85), 0.64 (0.54-0.76), and 0.50 (0.27-0.92), respectively, when compared with the data for metformin plus SUs.

CONCLUSIONS

Among people with YOD, taking add-on DPP-4 inhibitors was associated with lower risks of all-cause hospitalization and mortality than taking add-on SUs. DPP-4 inhibitors thus seem to be a suitable second-line OAD for such patients.

Long-term outcomes of adding alpha-glucosidase inhibitors in insulin-treated patients with type 2 diabetes

BACKGROUND

In insulin-treated patients with type 2 diabetes mellitus (T2DM), glycemic control is usually suboptimal.

METHODS

This study compared the risks of mortality and cardiovascular events in insulin-treated patients adding or not adding alpha-glucosidase inhibitors (AGIs).

RESULTS

This cohort study included data from the Taiwan National Health Insurance Research Database. In total, 17,417 patients newly diagnosed as having T2DM and undergoing insulin therapy during 2000-2012 were enrolled. Overall incidence rates of all-cause mortality, hospitalized coronary artery disease (CAD), stroke, and heart failure were compared between 4165 AGI users and 4165 matched nonusers. The incidence rates of all-cause mortality were 17.10 and 19.61 per 1000 person-years in AGI nonusers and users, respectively. Compared with nonusers, AGI users had a higher mortality risk [adjusted hazard ratio (aHR) = 1.21, 95% confidence interval (CI) = 1.05-1.40; p = 0.01]. Regarding AGI use, aHRs (95% CI) for cardiovascular death, non-cardiovascular death, hospitalized CAD, stroke, and heart failure were 1.20 (0.83-1.74), 1.27 (1.07-1.50), 1.12 (0.95-1.31), 0.98 (0.85-1.14), and 1.03 (0.87-1.22) respectively.

CONCLUSION

AGI use was associated with higher risks of all-cause mortality and non-cardiovascular death in insulin-treated patients with T2DM. Therefore, adding AGIs in insulin-treated patients may not be appropriate.

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

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

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.

Hypoglycaemic episodes increase the risk of ventricular arrhythmia and sudden cardiac arrest in patients with type 2 diabetes-A nationwide cohort study

BACKGROUND

The impact of hypoglycaemic episode (HE) on the risk of ventricular arrhythmia (VA) and sudden cardiac arrest (SCA) remains unclear. We hypothesized that HE increases the risk of both VA and SCA and that glucose-lowering agents causing HE also increase the risk of VA/SCA in patients with type 2 diabetes (T2D).

METHODS

Patients aged 20 years or older with newly diagnosed T2D were identified using the Taiwan National Health Insurance Database. HE was defined as the presentation of hypoglycaemic coma or specified/unspecified hypoglycaemia. The control group consisted of T2D patients without HE. The primary outcome was the occurrence of VA (including ventricular tachycardia and fibrillation) and SCA during the defined follow-up periods. A multivariate Cox hazards regression model was used to evaluate the hazard ratio (HR) for VA or SCA.

RESULTS

A total of 54 303 patients were screened, with 1037 patients with HE assigned to the HE group and 4148 frequency-matched patients without HE constituting the control group. During a mean follow-up period of 3.3 ± 2.5 years, 29 VA/SCA events occurred. Compared with the control group, HE group had a higher incidence of VA/SCA (adjusted HR: 2.42, P = .04). Patients who had used insulin for glycaemic control showed an increased risk of VA/SCA compared with patients who did not receive insulin (adjusted HR: 3.05, P = .01).

CONCLUSIONS

The HEs in patients with T2D increased the risk of VA/SCA, compared with those who did not experience HEs. Use of insulin also independently increased the risk of VA/SCA.

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.

Treatment of Diabetes in Older Adults: An Endocrine Society* Clinical Practice Guideline

OBJECTIVE

The objective is to formulate clinical practice guidelines for the treatment of diabetes in older adults.

CONCLUSIONS

Diabetes, particularly type 2, is becoming more prevalent in the general population, especially in individuals over the age of 65 years. The underlying pathophysiology of the disease in these patients is exacerbated by the direct effects of aging on metabolic regulation. Similarly, aging effects interact with diabetes to accelerate the progression of many common diabetes complications. Each section in this guideline covers all aspects of the etiology and available evidence, primarily from controlled trials, on therapeutic options and outcomes in this population. The goal is to give guidance to practicing health care providers that will benefit patients with diabetes (both type 1 and type 2), paying particular attention to avoiding unnecessary and/or harmful adverse effects.

Second-line glucose-lowering drugs added to metformin and the risk of hospitalization for heart failure: A nationwide cohort study

AIM

To compare the risks of hospitalization for heart failure (HHF) associated with sulfonylurea (SU), dipeptidyl peptidase-4 inhibitor (DPP-4i), and thiazolidinedione (TZD) as add-on medications to metformin (MET) therapy using the data of Korean adults with type-2 diabetes from the Korean National Health Insurance database.

METHODS

We identified 98,383 people who received SU (n = 42,683), DPP-4i (n = 50,310), or TZD (n = 5,390) added to initial treatment of MET monotherapy in patients with type-2 diabetes. The main outcome was the hospitalization for HHF. Hazard ratios for HHF by type of second-line glucose-lowering medication were estimated by Cox-proportional hazard models. Sex, age, duration of MET monotherapy, Charlson Comorbidity Index and additional comorbidities, and calendar year were controlled as potential confounders.

RESULTS

The observed numbers (rate per 100,000 person-years) of HHF events were 1,129 (658) for MET+SU users, 710 (455) for MET+DPP-4i users, and 110 (570) for MET+TZD users. Compared to that for MET+SU users (reference group), the adjusted hazard ratios for HHF events were 0.76 (95% confidence interval 0.69-0.84) for MET+DPP-4i users and 0.96 (95% confidence interval 0.79-1.17) for MET+TZD users.

CONCLUSION

DPP-4i as an add-on therapy to MET may lower the risks of HHF compared with SU.

Cardiovascular Benefits of Acarbose vs Sulfonylureas in Patients With Type 2 Diabetes Treated With Metformin

CONTEXT

Although α-glucosidase inhibitors (AGIs) have been shown to reduce the risk of myocardial infarction in patients with impaired glucose tolerance, the cardiovascular benefits of AGIs in those with type 2 diabetes (T2D) remains unclear.

OBJECTIVE

We compared the clinical outcomes of adding acarbose vs sulfonylureas to metformin therapy in patients with T2D.

DESIGN, SETTING, AND PARTICIPANTS

The study population was drawn from the database of the Diabetes Pay-for-Performance program in Taiwan. Sulfonylureas and acarbose were prescribed to 196,143 and 14,306 patients with T2D, respectively, from 2004 to 2015, who had been treated with metformin. A propensity score-matched cohort study was conducted. The patients were followed up for clinical adverse events of all-cause mortality and hospitalizations of major atherosclerotic events (i.e., myocardial infarction and ischemic stroke), heart failure, or hypoglycemia.

RESULTS

A total of 14,306 propensity score-matched pairs (age, 55.8 ± 13.1 years; 47.8% men) were enrolled in the present analysis. Compared with sulfonylureas as the add-on therapy to metformin, the use of acarbose was associated with significantly lower risks of hospitalizations for major atherosclerotic events [hazard ratio (HR), 0.69; 95% CI, 0.52 to 0.91], ischemic stroke (HR, 0.68; 95% CI, 0.49 to 0.94), and hypoglycemia (HR, 0.23; 95% CI, 0.08 to 0.71), after accounting for major confounding factors.

CONCLUSIONS

In T2D treatment, the use of acarbose as an add-on remedy to metformin was associated with lower risks of major atherosclerotic events, ischemic stroke, and hypoglycemia compared with the use of sulfonylurea as an add-on remedy.

Metformin combined with dipeptidyl peptidase-4 inhibitors or metformin combined with sulfonylureas in patients with type 2 diabetes: A real world analysis of the South Korean national cohort

AIMS

We explored the risks associated with metformin plus sulfonylurea (MET + SU) or MET plus a dipeptidyl peptidase-4 inhibitor (MET + DPP4i) for hypoglycemia, cardiovascular disease (CVD) events and all-cause mortality in type 2 diabetes (T2D) patients with comorbidities.

METHODS

This retrospective cohort study is based on the South Korean National Health Insurance Service-National Sample Cohort, enrolling T2D patients with one or more diabetes-related comorbidities who switched from monotherapy to MET + SU or MET + DPP4i between July 1, 2008 and December 31, 2013. The risk of hypoglycemia, CVD events and all-cause mortality was examined using Cox's proportional hazard modeling and propensity score matching.

RESULTS

Overall, 5693 patients with a mean of 2.6 comorbidities in addition to diabetes were included. Compared with MET + SU, MET + DPP4i treatment was associated with a lower risk of hypoglycemia, CVD events and all-cause mortality; adjusted HRs (95% CI), 0.39 (0.18-0.83), 0.72 (0.54-0.97), and 0.64 (0.39-1.05), respectively. Propensity score matching showed comparable results. In further subgroup analyses according to comorbidity type and number, MET + DPP4i was associated with less CVD events and all-cause mortality compared to MET + SU. This increased with more complex comorbid status.

CONCLUSIONS

In T2D patients with comorbidities, MET + DPP4i treatment is associated with lower risks of CVD events and all-cause mortality compared with MET + SU, independent of type or number of comorbidities. A more complex comorbid status further increases this effect.

Glitazones and alpha-glucosidase inhibitors as the second-line oral anti-diabetic agents added to metformin reduce cardiovascular risk in Type 2 diabetes patients: a nationwide cohort observational study

Objective

Metformin is the standard first-line drug for patients with Type 2 diabetes (T2DM). However, the optimal second-line oral anti-diabetic agent (ADA) remains unclear. We investigated the cardiovascular risk of various ADAs used as add-on medication to metformin in T2DM patients from a nationwide cohort.

Methods

T2DM patients using different add-on oral ADAs after an initial metformin therapy of > 90 days were identified from the Taiwan National Health Insurance Database. Five classes of ADAs, including sulphonylureas (SU), glinides, thiazolidinediones (TZD), alpha-glucosidase inhibitors (AGI), and dipeptidyl peptidase-4 inhibitors (DPP-4I) were selected for analysis. The reference group was the SU added to metformin. Patients were excluded if aged < 20 years, had a history of stroke or acute coronary syndrome (ACS), or were receiving insulin treatment. The primary outcomes included any major adverse cardiovascular event (MACE) including ACS, ischemic/hemorrhagic stroke, and death. A Cox regression model was used to estimate the hazard ratio (HR) for MACE.

Results

A total of 26,742 patients receiving their add-on drug to metformin of either SU (n = 24,277), glinides (n = 962), TZD (n = 581), AGI (n = 808), or DPP-4I (n = 114) were analyzed. After a mean follow-up duration of 6.6 ± 3.4 years, a total of 4775 MACEs occurred. Compared with the SU+metformin group (reference), the TZD+metformin (adjusted HR: 0.66; 95% CI 0.50–0.88, p = 0.004) and AGI+metformin (adjusted HR: 0.74; 95% CI 0.59–0.94, p = 0.01) groups showed a significantly lower risk of MACE.

Conclusion

Both TZD and AGI, when used as an add-on drug to metformin were associated with lower MACE risk when compared with SU added to metformin in this retrospective cohort study.

Trial registration CE13152B-3. Registered 7 Mar, 2013, retrospectively registered

Electronic supplementary material

The online version of this article (10.1186/s12933-018-0663-6) contains supplementary material, which is available to authorized users.

Evaluating the Diabetes-Cardiology interface: a glimpse into the diabetes management of cardiology inpatients in western Sydney's 'diabetes hotspot' and the establishment of a novel model of care

BACKGROUND

Approximately two-thirds of individuals presenting to emergency departments in Western Sydney have glucose dysregulation, accelerating their risk of cardiovascular disease (CVD). We evaluated the prevalence and management of type 2 diabetes (T2D) in cardiology inpatients in Western Sydney. A novel model of care between diabetes and cardiology specialist hospital teams (joint specialist case conferencing, JSCC) is described herein and aimed at aligning clinical services and upskilling both teams in the management of the cardiology inpatient with comorbid T2D.

METHODS

Cardiology inpatients at Blacktown-Mount Druitt Hospital were audited during a 1-month period.

RESULTS

233 patients were included, mean age 64 ± 16 years, 60% were male, 27% overweight and 35% obese. Known T2D comprised 36% (n = 84), whereas 6% (n = 15) had a new diagnosis of T2D, of which none of the latter were referred for inpatient/outpatient diabetes review. Approximately, 27% (n = 23) and 7% (n = 6) of known diabetes patients suffered hyper- and hypoglycaemia, respectively, and 51% (n = 43) had sub-optimally controlled T2D (i.e. HbA1c > 7.0%); over half (51%, n = 51) had coronary artery disease. Only two patients were treated with an SGLT2 inhibitor and no patients were on glucagon like peptide-1 receptor analogues. The majority were managed with metformin (62%) and therapies with high hypoglycaemic potential (e.g., sulfonylureas (29%)) and in those patients treated with insulin, premixed insulin was used in the majority of cases (47%).

CONCLUSIONS

Undiagnosed T2D is prevalent and neglected in cardiology inpatients. Few patients with comorbid T2D and CVD were managed with therapies of proven cardiac and mortality benefit. Novel models of care may be beneficial in this high-risk group of patients and discussed herein is the establishment of the diabetes-cardiology JSCC service delivery model which has been established at our institution.

Effectiveness and safety of dipeptidyl peptidase 4 inhibitors in the management of type 2 diabetes in older adults: a systematic review and development of recommendations to reduce inappropriate prescribing

Background

Preventable drug-related hospital admissions can be associated with drugs used in diabetes and the benefits of strict diabetes control may not outweigh the risks, especially in older populations. The aim of this study was to look for evidence on risks and benefits of DPP-4 inhibitors in older adults and to use this evidence to develop recommendations for the electronic decision support tool of the PRIMA-eDS project.

Methods

Systematic review using a staged approach which searches for systematic reviews and meta-analyses first, then individual studies only if prior searches were inconclusive. The target population were older people (≥65 years old) with type 2 diabetes. We included studies reporting on the efficacy and/or safety of DPP-4 inhibitors for the management of type 2 diabetes. Studies were included irrespective of DPP-4 inhibitors prescribed as monotherapy or in combination with any other drug for the treatment of type 2 diabetes. The target intervention was DPP-4 inhibitors compared to placebo, no treatment, other drugs to treat type 2 diabetes or a non-pharmacological intervention.

Results

Thirty studies (reported in 33 publications) were included: 1 meta-analysis, 17 intervention studies and 12 observational studies. Sixteen studies were focused on older adults and 14 studies reported subgroup analyses in participants ≥65, ≥70, or ≥75 years. Comorbidities were reported by 26 studies and frailty or functional status by one study. There were conflicting findings regarding the effectiveness of DPP-4 inhibitors in older adults. In general, DPP-4 inhibitors showed similar or better safety than placebo and other antidiabetic drugs. However, these safety data are mainly based on short-term outcomes like hypoglycaemia in studies with HbA1c control levels recommended for younger people. One recommendation was developed advising clinicians to reconsider the use of DPP-4 inhibitors for the management of type 2 diabetes in older adults with HbA1c <8.5% because of scarce data on clinically relevant benefits of their use. Twenty-two of the included studies were funded by pharmaceutical companies and authored or co-authored by employees of the sponsor.

Conclusions

Other than the surrogate endpoint of improved glycaemic control, data on clinically relevant benefits of DPP-4 inhibitors in the treatment of type 2 diabetes mellitus in older adults is scarce. DPP-4 inhibitors might have a lower risk of hypoglycaemia compared to other antidiabetic drugs but data show conflicting findings for long-term benefits. Further studies are needed that evaluate the risks and benefits of DPP-4 inhibitors for the management of type 2 diabetes mellitus in older adults, using clinically relevant outcomes and including representative samples of older adults with information on their frailty status and comorbidities. Studies are also needed that are independent of pharmaceutical company involvement.

Electronic supplementary material

The online version of this article (doi:10.1186/s12877-017-0571-8) contains supplementary material, which is available to authorized users.

Cardiovascular events associated with second-line anti-diabetes treatments: analysis of real-world Korean data

AIM

To compare the risks of cardiovascular disease (CVD) and all-cause mortality associated with sulfonylurea (SU), dipeptidyl peptidase-4 inhibitor (DPP4i) and thiazolidinedione (TZD) as add-on medications to metformin (MET) therapy in people with Type 2 diabetes.

METHODS

We identified 40 263 individuals who used SU (n = 11 582), DPP4i (n = 26 623) or TZD (n = 2058) in addition to MET between January 2013 and June 2015 from the database of the Korean National Health Insurance, the single-payer healthcare system in South Korea. Cox proportional hazard models were used to estimate hazard ratios for major CVD event (coronary artery disease, heart failure, stroke or transient ischaemic attack) development and all-cause mortality by second-line anti-diabetes medication type. Age, sex, duration of MET monotherapy, calendar year and comorbid conditions were adjusted as potential confounders.

RESULTS

The observed numbers of CVD events (total observed person-time) were 485 (18 778 person-years) for MET + SU, 744 (40 374 person-years) for MET + DPP4i and 60 (3014 person-years) for MET + TZD users. Compared with MET + SU users, the fully adjusted hazard ratios for CVD events were 0.79 [95% confidence interval (CI): 0.71-0.89] for MET + DPP4i users and 0.85 (95% CI: 0.65-1.11) for MET + TZD users. The corresponding hazard ratios for all-cause mortality were 0.84 (95% CI: 0.66-1.07) for MET + DPP4i users and 0.67 (95% CI: 0.35-1.28) for MET + TZD users.

CONCLUSION

Analysis of Korea National Health Insurance database showed that MET + DPP4i treatment for diabetes had a lower CVD risk than MET + SU treatment.

Comparative cardiovascular risks of dipeptidyl peptidase 4 inhibitors with other second- and third-line antidiabetic drugs in patients with type 2 diabetes

AIMS

Dipeptidyl peptidase 4 inhibitors (DPP4is) are suggested as a second- and third-line antidiabetic treatment for type 2 diabetes. Previous studies assessed only the cardiovascular effects of DPP4is as a second-line treatment, included sulphonylurea as the only comparator, and yielded inconclusive results on the risk of heart failure. The present study therefore evaluated the comparative cardiovascular risks of DPP4is with other second- and third-line antidiabetic drugs.

METHODS

Based on a large nationwide diabetic cohort, 113 051 patients with type 2 diabetes newly on metformin-based dual or triple therapy were identified in 2009-2011 and followed until 2013, or death if this occurred sooner. Primary interest targeted hospitalizations for ischaemic stroke, myocardial infarction and heart failure. Secondary outcomes were hypoglycaemia and all-cause mortality. Cox proportional hazards models were performed to assess time-to-event hazard ratio between propensity score-matched antidiabetic treatment groups.

RESULTS

DPP4is as a second-line add-on to metformin had a significantly lower stroke risk [hazard ratio (HR) 0.817 (95% confidence interval 0.687, 0.971)] and all-cause mortality [HR 0.825 (0.687, 0.992)] than those for sulphonylurea. DPP4is as a third-line add-on to metformin and sulphonylurea combined dual therapy had a significantly lower risk for stroke [HR 0.826 (0.740, 0.923)] and all-cause mortality [HR 0.784 (0.701, 0.878)] than those for acarbose, and significantly lower risks for stroke [HR 0.653 (0.542, 0.786)], heart failure [HR 0.721 (0.568, 0.917)] and all-cause mortality [HR 0.689 (0.594, 0.703)] than those for meglitinide.

CONCLUSIONS

DPP4is as a second- or third-line add-on treatment provided cardiovascular benefits and posed no increased risks for heart failure, hypoglycaemia or death.

Diabetes management in older people: a focus on cardiovascular risk reduction

Cardiovascular disease remains the most common cause of death in persons with diabetes regardless of age. Increasing age combined with diabetes exert a synergistic effect on the vascular system increasing the atherosclerosis burden in older people with diabetes. Due to their high baseline risk, they stand to benefit most from interventions to reduce cardiovascular risk. Older people with diabetes are functionally heterogeneous and their management is challenging. Fit and independent individuals are likely to benefit from tight targets while a relaxed approach putting quality of life at the heart of management plans is more appropriate in the frail and dependent individuals with limited life expectancy.

Cardiovascular safety of glucose-lowering agents as add-on medication to metformin treatment in type 2 diabetes: report from the Swedish National Diabetes Register

AIM

To investigate the relative safety of various glucose-lowering agents as add-on medication to metformin in type 2 diabetes in an observational study linking five national health registers.

RESEARCH DESIGN AND METHODS

Patients with type 2 diabetes who had been on metformin monotherapy and started another agent in addition to metformin were eligible for inclusion. The study period was 2005-2012. Adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) of mortality, cardiovascular disease (CVD), coronary heart disease (CHD), stroke and congestive heart failure (CHF) were estimated using Cox proportional hazards models, weighted for a propensity score.

RESULTS

Of the 20 422 patients included in the study, 43% started on second-line treatment with sulphonylurea (SU), 21% basal insulin, 12% thiazolidinedione (TZD), 11% meglitinide, 10% dipeptidyl peptidase-4 (DPP-4) inhibitor, 1% glucagon-like peptide-1 (GLP-1) receptor agonist and 1% acarbose. At the index date, the mean patient age was ~60 years for all groups except the GLP-1 receptor agonist (56.0 years) and SU (62.9 years) groups. Diabetes duration and glycated haemoglobin levels were similar in all groups. When compared with SU, basal insulin was associated with an 18% higher risk and TZD with a 24% lower risk of mortality [HR 1.18 (95% CI 1.03-1.36) and 0.76 (95% CI 0.62-0.94)], respectively. DPP-4 inhibitor treatment was associated with significantly lower risks of CVD, fatal CVD, CHD, fatal CHD and CHF.

CONCLUSIONS

This nationwide observational study showed that second-line treatment with TZD and DPP-4 inhibitor as add-on medication to metformin were associated with significantly lower risks of mortality and cardiovascular events compared with SU, whereas basal insulin was associated with a higher risk of mortality.

Development of vascular complications and bladder carcinoma in diabetics using pioglitazone: A five-year Indian review

BACKGROUND

Pioglitazone has better cardiovascular outcomes and a questionable relationship with bladder carcinoma in diabetes mellitus, type II (DM-2). We sought to evaluate the role of pioglitazone in the Indian population.

METHODS

This is a retrospective study at an academic medical center in India. All DM-2 patients in 2008 with a new prescription of pioglitazone were age- and gender-matched with non-users. We excluded patients with gestational DM or DM type I. They were followed forward for five years and demographic data, micro- and macro-vascular complications, mortality, and bladder carcinoma were recorded. Two-tailed p ≤ 0.05 was considered statistically significant.

RESULTS

Two cohorts of 260 patients, with mean age of 58 ± 11 years with 413 (79.4%) males, were followed for five years. Pioglitazone users had higher hypertension, obesity, DM-2 family history (all p < 0.003), and use of insulin and oral hypoglycemics (all p < 0.0001) in comparison to non-users. HbA1c was not different between groups. Over five years, pioglitazone users had lesser retinopathy and myocardial infarctions (all p < 0.01). Five cases of bladder carcinoma were noted, all in the pioglitazone group, however without statistical significance. Baseline variables, including mean daily pioglitazone dose, were not statistically different between patients with and without bladder carcinoma. Nephropathy and MI were independent predictors for development of bladder carcinoma within pioglitazone users.

CONCLUSIONS

Pioglitazone users had significantly lesser myocardial infarctions and retinopathy despite more difficult to control DM 2. In an age- and gender-matched cohort of users and non-users, pioglitazone did not contribute to development of bladder cancer in the Indian population.

Sulphonylurea compared to DPP-4 inhibitors in combination with metformin carries increased risk of severe hypoglycemia, cardiovascular events, and all-cause mortality

AIMS

There are safety concerns related to sulphonylurea treatment. The objective of this nationwide study was to compare the risk of cardiovascular disease (CVD), all-cause mortality and severe hypoglycemia in patients with type 2 diabetes (T2D) starting second-line treatment with either metformin+sulphonylurea or metformin+dipeptidyl peptidase-4 inhibitor (DPP-4i).

METHODS

All patients with T2D in Sweden who initiated second-line treatment with metformin+sulphonylurea or metformin+DPP-4i during 2006-2013 (n=40,736 and 12,024, respectively) were identified in this nationwide study. The Swedish Prescribed Drug Register and the Cause of Death and National Patient Registers were used, and Cox survival models adjusted for age, sex, fragility, prior CVD, and CVD-preventing drugs were applied to estimate risks of events. Propensity score adjustments and matching methods were used to test the results.

RESULTS

Of 52,760 patients; 77% started metformin+SU and 23% metformin+DPP-4i. Crude incidences for severe hypoglycemia, CVD, and all-cause mortality in the SU cohort were 2.0, 19.6, and 24.6 per 1000 patient-years and in the DPP-4i cohort were 0.8, 7.6, and 14.9 per 1000 patient-years, respectively. Sulphonylurea compared with DPP4i was associated with higher risk of subsequent severe hypoglycemia, fatal and nonfatal CVD, and all-cause mortality; adjusted HR (95% CI): 2.07 (1.11-3.86); 1.17 (1.01-1.37); and 1.25 (1.02-1.54), respectively. Results were confirmed by additional propensity-adjusted and matched analyses. Among the SU drugs, glibenclamide had the highest risks.

CONCLUSIONS

Metformin+SU treatment was associated with an increased risk of subsequent severe hypoglycemia, cardiovascular events, and all-cause mortality compared with metformin+DPP4i. Results from randomized trials will be important to elucidate causal relationships.

Association Between Severe Hypoglycemia and Cardiovascular Disease Risk in Japanese Patients With Type 2 Diabetes

Background

It remains unclear whether severe hypoglycemia is associated with cardiovascular disease (CVD) in Asian populations with type 2 diabetes (T2D). Furthermore, no study in Japan, where the prescription patterns differ from those in other countries, has examined this association.

Methods and Results

We retrospectively included 58 223 patients (18–74 years old) with T2D. First, we examined the potential predictors of severe hypoglycemia. Then, we investigated the association between severe hypoglycemia and CVD risk. Finally, we performed an updated systematic review and meta‐analysis to incorporate our findings and recently published studies into the previous systematic review and meta‐analysis. During 134 597 person‐years from cumulative observation periods, 128 persons experienced severe hypoglycemia and 550 developed CVD events. In a multivariate Cox proportional hazard model, severe hypoglycemia was strongly and positively associated with the risk of CVD (multivariate‐adjusted adjusted hazard ratio, 3.39; 95% CI, 1.25–9.18). In a propensity score–matched cohort that had similar baseline characteristics for patients with severe hypoglycemia and those without, severe hypoglycemia was more strongly associated with the risk of CVD. An updated systematic review and meta‐analysis that included 10 studies found that severe hypoglycemia was associated with an ≈2‐fold increased risk of CVD (pooled relative risk, 1.91; 95% CI, 1.69–2.15).

Conclusions

Our results suggest that severe hypoglycemia is strongly associated with an increased risk of CVD in Japanese patients with T2D, further supporting the notion that avoiding severe hypoglycemia may be important in preventing CVD in this patient population.

Risks of cardiovascular diseases associated with dipeptidyl peptidase-4 inhibitors and other antidiabetic drugs in patients with type 2 diabetes: a nation-wide longitudinal study

Background

Several antidiabetic drugs (i.e., sulfonylureas; SU, rosiglitazone) have been reported to be associated with increased risks of cardiovascular diseases (CVD) in patients with type 2 diabetes mellitus (T2DM). Dipeptidyl peptidase-4 inhibitors (DPP4i) are newly available antidiabetic drugs. Most studies only compared DPP4i with a placebo or SU, or targeted a specific CVD event of interest (i.e., heart failure; HF). Comparative research of CVD risks of DPP4i with other antidiabetic drugs (i.e., metformin, thiazolidinediones, meglitinides, acarbose, and insulin) remains scarce. This study was aimed to assess comparative risks of CVD, including ischemic stroke, myocardial infarction (MI) and HF, and hypoglycemia of DPP4i with other antidiabetic drugs.

Methods

We utilized Taiwan’s National Health Insurance Research Database. A total of 123,050 T2DM patients newly prescribed oral antidiabetic treatments were identified in 2009–2010 and followed until 2013. Outcome endpoints included a composite of CVD events: hospitalizations for ischemic stroke, MI and HF, and hypoglycemia. Time-varying Cox proportional hazards regression was applied to assess the time to event hazards of various antidiabetic drugs, adjusted for patients’ demographics, comorbidity, diabetic complications, and co-medications. Additional analyses were performed for the patients with and without CVD history, respectively.

Results

DPP4i users had significantly lower CVD risks as compared to that of non-DPP4i users (adjusted hazard ratio [aHR]: 0.83, 95 % confidence interval [CI]: 0.76–0.91). Compared to DPP4i users, meglitinides (aHR 1.3, 95 % CI 1.20–1.43) and insulin users (aHR 3.73, 95 % CI 3.35, 4.14) had significantly higher risks for composite CVD, as well as those for stroke, MI, HF, and hypoglycemia. Additionally, metformin users had significantly lower risks for composite CVD risk (aHR 0.87, 95 % CI 0.79–0.94), as well as those for MI, HF, and hypoglycemia, as compared to those of DPP4i users. Although there was a trend toward low CVD risks in pioglitazone users, the role of potential confounding by indication cannot be excluded.

Conclusions

DPP4i-treated T2DM patients had lower risks for CVD as compared to those for non-DPP4i users, except metformin users.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-016-0350-4) contains supplementary material, which is available to authorized users.