Comparative effectiveness of incretin-based therapies and the risk of death and cardiovascular events in 38,233 metformin monotherapy users

Sulfonylureas and the Risk of Ventricular Arrhythmias Among People with Type 2 Diabetes: A Systematic Review of Observational Studies

Previous studies have suggested an association between sulfonylureas and an increased risk of cardiovascular death among patients with type 2 diabetes. A potential mechanism involves sulfonylurea-induced ventricular arrhythmias (VAs). We conducted a systematic review of observational studies to determine whether the use of sulfonylureas, compared with the use of other antihyperglycemic drugs, is associated with the risk of VA (ventricular tachycardia, ventricular fibrillation, and premature ventricular complexes), cardiac arrest, and sudden cardiac death among patients with type 2 diabetes. Two independent reviewers searched MEDLINE, EMBASE, CINAHL Plus, CENTRAL, and ClinicalTrials.gov from inception to July 2021 for observational studies comparing sulfonylureas vs. other antihyperglycemic therapies or intraclass comparisons of sulfonylureas. Our systematic review included 17 studies (1,607,612 patients). Per Risk Of Bias In Non-randomized Studies of Interventions (ROBINS)-I, there were few high-quality studies (2 studies at moderate risk of bias; 4 at serious risk; and 11 at critical risk). All studies at a moderate or serious risk of bias reporting comparisons with other therapies were consistent with an increased risk of VA. Sulfonylureas were associated with a higher risk of arrhythmia vs. dipeptidyl peptidase-4 inhibitors (adjusted hazard ratio (aHR): 1.52, 95% confidence interval (CI): 1.27-1.80) and of VA vs. metformin (aHR: 1.52, 95% CI: 1.10-2.13). One moderate quality study reported inconsistent results for a composite of cardiac arrest/VA in analyses of US Medicaid claims and Optum claims data. Our systematic review suggests that, among higher-quality observational studies, sulfonylureas are associated with an increased risk of VA. However, we identified few methodologically rigorous studies, underscoring the need for additional real-world studies.

Three-step matching algorithm to enhance between-group comparability and minimize confounding in comparative effectiveness studies

We developed a three-step matching algorithm to enhance the between-group comparability for comparative drug effect studies involving prevalent new-users of the newer study drug versus older comparator drug(s). The three-step matching scheme is to match on: (1) index date of initiating the newer study drug to align the cohort entry time between study groups, (2) medication possession ratio measures that consider prior exposure to all older comparator drugs, and (3) propensity scores estimated from potential confounders. Our approach is illustrated with a comparative cardiovascular safety study of glucagon-like peptide-1 receptor agonist (GLP-1ra) versus sulfonylurea (SU) in type 2 diabetes patients using Taiwan’s National Health Insurance Research Database 2003–2015. 66% of 3195 GLP-1ra users had previously exposed to SU. The between-group comparability was well-achieved after implementing the matching algorithm (i.e., standardized mean difference < 0.2 for all baseline patient characteristics). Compared to SU, the use of GLP-1ra yielded a significantly reduced risk of the primary composite cardiovascular events (hazard ratio [95% confidence interval]: 0.71 [0.54–0.95], p = 0.022). Our matching scheme can enhance the between-group comparability in prevalent new-user cohort designs to minimize time-related bias, improve confounder adjustment, and ensure the reliability and validity of study findings.

Cardiovascular Outcome Trials in Type 2 Diabetes: What Do They Mean for Clinical Practice?

IN BRIEF Cardiovascular disease is the leading cause of morbidity and mortality in people with diabetes, and deaths from heart disease are two to four times higher among adults with type 2 diabetes. Trials such as the U.K. Prospective Diabetes Study, ACCORD (Action to Control Cardiovascular Risk in Diabetes), ADVANCE (Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation), and VADT (Veteran's Affairs Diabetes Trial) produced mixed findings regarding whether intensive glycemic control results in improved cardiovascular (CV) outcomes for patients with diabetes. In response to concerns, including the CV safety of the thiazolidinedione rosiglitazone, the U.S. Food and Drug Administration and subsequently the European Medicines Agency issued guidance that trials should be conducted to prove that antihyperglycemic agents have acceptable CV risk profiles. In this article, the authors review the study designs and results of CV outcomes trials conducted with sodium-glucose cotransporter 2 inhibitors and glucagon-like peptide 1 receptor agonists and discuss how these may affect clinical practice.

Effects on clinical outcomes of intensifying triple oral antidiabetic drug (OAD) therapy by initiating insulin versus enhancing OAD therapy in patients with type 2 diabetes: A nationwide population-based, propensity-score-matched cohort study

AIMS

To compare the effects of initiating insulin as a fourth-line antidiabetic therapy with the effects of enhancing oral antidiabetic drug (OAD) therapy in patients with type 2 diabetes mellitus (T2DM) with triple OAD therapy failure.

MATERIALS AND METHODS

We conducted a nationwide population-based, retrospective cohort study involving 1022 (without prevalent diabetes-related complications [PDRCs]) and 2077 (with/without PDRCs) propensity score-matched pairs of fourth-line insulin therapy users and enhanced OAD therapy users identified in the period 2004 to 2010. Clinical outcomes including a composite cardiovascular outcome (myocardial infarction, stroke, heart failure or ischaemic heart disease), peripheral vascular disease (PVD), hypoglycaemia and all-cause mortality were assessed up to 2013. Hypoglycaemia was adjusted in Cox models to consider its potential effect on study outcomes.

RESULTS

In a T2DM cohort without PDRCs, fourth-line insulin therapy was not associated with greater risks of clinical outcomes, except hypoglycaemia (hazard ratio [HR] 1.45, 95% confidence interval [CI] 1.02-2.07), compared with enhanced OAD therapy. Among patients with T2DM with/without PDRCs, fourth-line insulin therapy was associated with greater risks of the composite cardiovascular outcome (HR 1.23, 95% CI 1.03-1.46), heart failure (HR 1.59, 95% CI 1.12-2.25), ischaemic heart disease (HR 1.37, 95% CI 1.09-1.73), PVD (HR 1.17, 95% CI 1.00-1.36), hypoglycaemia (HR 1.49, 95% CI 1.20-1.85) and all-cause mortality (HR 1.48, 95% CI 1.01-2.17), but adjustment for hypoglycaemia significantly attenuated the risk of heart failure (HR 1.34, 95% CI 0.92-1.94), PVD (HR 1.15, 95% CI 0.98-1.34) and all-cause mortality (HR 1.30, 95% CI 0.84-1.99).

CONCLUSIONS

Initiation of fourth-line insulin therapy can be considered for patients with T2DM with triple OAD therapy failure, and the importance of awareness and prevention of hypoglycaemia among insulin-treated patients with T2DM cannot be overstated.

Examining the risk of depression or self-harm associated with incretin-based therapies used to manage hyperglycaemia in patients with type 2 diabetes: a cohort study using the UK Clinical Practice Research Datalink

OBJECTIVES

To compare population-based incidence rates of new-onset depression or self-harm in patients initiating incretin-based therapies with that of sulfonylureas (SU) and other glucose-lowering agents.

DESIGN

Population-based cohort study.

SETTING

Patients attending primary care practices registered with the UK-based Clinical Practice Research Datalink (CPRD).

PARTICIPANTS

Using the UK-based CPRD, we identified two incretin-based therapies cohorts: (1) dipeptidyl peptidase-4 inhibitor (DPP-4i)-cohort, consisting of new users of DPP-4i and SU and (2) glucagon-like peptide-1 receptor agonists (GLP-1RA)-cohort, consisting of new users of GLP-1RA and SU, between January 2007 and January 2016. Patients with a prior history of depression, self-harm and other serious psychiatric conditions were excluded.

MAIN OUTCOME MEASURES

The primary study outcome comprised a composite of new-onset depression or self-harm. Unadjusted and adjusted Cox proportional hazards regression was used to quantify the association between incretin-based therapies and depression or self-harm. Deciles of High-Dimensional Propensity Scores and concurrent number of glucose-lowering agents were used to adjust for potential confounding.

RESULTS

We identified new users of 6206 DPP-4i and 22 128 SU in the DPP-4i-cohort, and 501 GLP-1RA and 16 409 SU new users in the GLP-1RA-cohort. The incidence of depression or self-harm was 8.2 vs 11.7 events/1000 person-years in the DPP-4i-cohort and 18.2 vs 13.6 events/1000 person-years in the GLP-1RA-cohort for incretin-based therapies versus SU, respectively. Incretin-based therapies were not associated with an increased or decreased incidence of depression or self-harm compared with SU (DPP-4i-cohort: unadjusted HR 0.70, 95% CI 0.51 to 0.96; adjusted HR 0.80, 95% CI 0.57 to 1.13; GLP-1RA-cohort: unadjusted HR 1.36, 95% CI 0.72 to 2.58; adjusted HR 1.25, 95% CI 0.63 to 2.50). Consistent results were observed for other glucose-lowering comparators including insulin and thiazolidinediones.

CONCLUSIONS

Our findings suggest that the two incretin-based therapies are not associated with an increased or decreased risk of depression or self-harm.

Are the favorable cardiovascular outcomes of empagliflozin treatment explained by its effects on multiple cardiometabolic risk factors? A simulation of the results of the EMPA-REG OUTCOME trial

AIMS

It is unclear whether the favorable impact of empagliflozin on cardiovascular outcomes (CVOs) is due to its effect on multiple cardiometabolic risk factors (CRFs).

METHODS

We used the Michigan Model for Diabetes, a validated computer simulation model, and published data from the EMPA-REG OUTCOME trial to estimate three-year CVOs in the placebo and pooled empagliflozin treatment groups to assess whether the observed benefits might be attributable to differences in CRFs.

RESULTS

When we programmed the model to match the baseline characteristics of the trial population and the reported trajectories of five CRFs (weight, HbA1c, systolic blood pressure, low- and high-density lipoprotein cholesterol), the simulated hazard ratio (HR) for the primary composite CVO did not differ from the reported result. The simulated HRs for fatal/nonfatal myocardial infarction and coronary revascularization procedure fell within the reported 95% confidence intervals (CIs), but those for fatal/nonfatal stroke, hospitalization for heart failure, cardiovascular death, and all-cause mortality fell outside the reported 95% CIs. The effects of empagliflozin on CRFs accounted for approximately half of the observed benefit for the primary composite CVO, but explained smaller proportions of risk reductions for hospitalization for heart failure, cardiovascular death, and all-cause mortality.

CONCLUSIONS

The effects of empagliflozin on multiple CRFs account for some but not all of reduced risks of CVOs in the EMPA-REG OUTCOME trial. More comparable control of established CRFs in type 2 diabetes CVO trials of antidiabetic agents with pleiotrophic effects would facilitate the interpretation of the observed outcomes.

Pharmacotherapy of type 2 diabetes: An update

Type 2 diabetes (T2DM) is a leading cause of morbidity and mortality worldwide and a major economic burden. The prevalence of T2DM is rising, suggesting more effective prevention and treatment strategies are necessary. The aim of this narrative review is to summarize the pharmacologic treatment options available for patients with T2DM. Each therapeutic class is presented in detail, outlining medication effects, side effects, glycemic control, effect on weight, indications and contraindications, and use in selected populations (heart failure, renal insufficiency, obesity and the elderly). We also present representative cost for each antidiabetic category. Then, we provide an individualized guide for initiation and intensification of treatment and discuss the considerations and rationale for an individualized glycemic goal.

No increased risk of cardiovascular events in older adults initiating dipeptidyl peptidase-4 inhibitors vs therapeutic alternatives

AIM

To compare the cardiovascular (CV) risk associated with dipeptidyl peptidase-4 (DPP-4) inhibitors relative to sulphonylureas (SUs) and thiazolidinediones (TZDs).

METHODS

During 2007 to 2013, using Medicare data for beneficiaries aged >65 years, we identified the following 2 cohorts of new-users, who had not been exposed to the drugs being compared in the 6 months before initiation: (1) DPP-4 inhibitor vs SU initiators and (2) DPP-4 inhibitor vs TZD initiators. Using propensity-score-adjusted Cox models accounting for competing risk by death, we estimated the hazard ratios (HRs), risk differences and 95% confidence intervals (CIs) for myocardial infarction (MI), stroke, hospitalization for heart failure (HF), and a combined outcome (MI, stroke, all-cause mortality).

RESULTS

In the DPP-4 inhibitor vs SU comparison, there were 30 130 DPP-4 inhibitor initiators and 68 382 SU initiators. Their mean age was 75 years, 41% were men and 55% had a baseline CV condition. The HR for the composite outcome was 0.75 (95% CI 0.72-0.79) over a median treatment duration of 1 year, but the 1-year risks of MI were 1.00 (95% CI 0.89-1.12) and 1.47 (95% CI 1.38-1.56) per 100 patients for DPP-4 inhibitors and SUs, respectively, and the corresponding stroke risks were 0.98 (95% CI 0.87-1.10) and 1.09 (95% CI 1.01-1.17). For the DPP-4 inhibitor vs TZD comparison, there were 20 596 DPP-4 inhibitor initiators and 13 526 TZD initiators without previous HF. Their mean age was 74 years, 42% were men and 30% had a baseline CV event. The composite outcome HR was 0.94 (95% CI 0.86-1.02) over a median treatment duration of 1 year. The 1-year risk for MI was ~0.90 and for stroke it was ~0.80 per 100 patients in both DPP-4 inhibitor and TZD initiators.

CONCLUSION

Although limited by the short treatment period, the present study suggests there is no increased short-term risk of MI, stroke or HF with DPP-4 inhibitors vs SUs/TZDs.

The cardiovascular safety trials of DPP-4 inhibitors, GLP-1 agonists, and SGLT2 inhibitors

In this paper, we review the results of large, double-blind, placebo-controlled randomized trials mandated by the US Food and Drug Administration to examine the cardiovascular safety of newly-approved antihyperglycemic agents in patients with type 2 diabetes. The cardiovascular effects of dipeptidyl peptidase-4 (DPP-4) inhibitors remain controversial: while these drugs did not reduce or increase the risk of primary, pre-specified composite cardiovascular outcomes, one DPP-4 inhibitor (saxagliptin) increased the risk of hospitalization for heart failure in the overall population; another (alogliptin) demonstrated inconsistent effects on heart failure hospitalization across subgroups of patients, and a third (sitagliptin) demonstrated no effect on heart failure. Evidence for cardiovascular benefits of glucagon-like peptide-1 (GLP-1) agonists has been similarly heterogeneous, with liraglutide and semaglutide reducing the risk of composite cardiovascular outcomes, but lixisenatide having no reduction or increase in cardiovascular risk. The effect of GLP-1 agonists on retinopathy remains a potential concern. In the only completed trial to date to assess a sodium-glucose cotransporter-2 (SGLT2) inhibitor, empagliflozin reduced the risk of composite cardiovascular endpoints, predominantly through its impact on cardiovascular mortality and heart failure hospitalization.