Semaglutide for cardiovascular event reduction in people with overweight or obesity: SELECT study baseline characteristics

OBJECTIVE

This paper describes the baseline characteristics of the Semaglutide Effects on Heart Disease and Stroke in Patients with Overweight or Obesity (SELECT) study, one of the largest cardiovascular (CV) outcome studies in the field of obesity, which evaluates the effect of semaglutide versus placebo on major CV events.

METHODS

SELECT enrolled individuals with overweight or obesity without diabetes, with prior myocardial infarction, stroke, and/or peripheral artery disease. This study reports participants' baseline characteristics in the full study population and subgroups defined by baseline glycated hemoglobin (HbA_1c ; <5.7%, ≥5.7 to <6.0%, ≥6.0 to <6.5%), baseline waist to height ratio tertile, and qualifying prior CV event or condition.

RESULTS

The study enrolled 17,605 participants (72.5% male) with an average (SD) age of 61.6 (8.9) years and BMI of 33.34 (5.04) kg/m² . The most common prior CV event was myocardial infarction (76.3% of participants), followed by stroke (23.3%) and peripheral artery disease (8.6%). Furthermore, 24.3% had a heart failure diagnosis. Two-thirds of participants (66%) had HbA_1c in the prediabetes range (5.7%-6.4%). Across groups of increasing HbA_1c , prevalence of all CV risk factors increased.

CONCLUSIONS

The enrolled population in SELECT includes participants across a broad range of relevant risk categories. This will allow the study to garner information about the CV benefits of semaglutide across these relevant clinical subgroups.

Effects of glucagon-like peptide-1 receptor agonists liraglutide and semaglutide on cardiovascular and renal outcomes across body mass index categories in type 2 diabetes: Results of the LEADER and SUSTAIN 6 trials

Associations between body mass index (BMI) and the cardiovascular (CV) and kidney efficacy of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) in patients with type 2 diabetes (T2D) are uncertain; therefore, data analysed separately from the Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results (LEADER) trial and the Trial to Evaluate Cardiovascular and Other Long-term Outcomes with Semaglutide in Subjects with Type 2 Diabetes (SUSTAIN 6) were examined. These international, randomized, placebo-controlled trials investigated liraglutide and semaglutide (both subcutaneous) in patients with T2D and at high risk of CV events. In post hoc analyses, patients were categorized by baseline BMI (<25, ≥25-<30, ≥30-<35 and ≥35 kg/m² ), and CV and kidney outcomes with GLP-1 RA versus placebo were analysed. All baseline BMI data from LEADER (n = 9331) and SUSTAIN 6 (n = 3290) were included (91% and 92% of patients with overweight or obesity, respectively). In SUSTAIN 6, nominally significant heterogeneity of semaglutide efficacy by baseline BMI was observed for CV death/myocardial infarction/stroke (major adverse CV events, primary outcome of both; P_interaction = .02); otherwise, there was no statistical heterogeneity for either GLP-1 RA versus placebo across BMI categories for key CV and kidney outcomes. The lack of statistical heterogeneity from these cardiorenal outcomes implies that liraglutide and semaglutide may be beneficial for many patients and is probable not to depend on their baseline BMI, but further study is needed.

Cardiovascular Risk Reduction With Liraglutide: An Exploratory Mediation Analysis of the LEADER Trial

OBJECTIVE

The Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results (LEADER) trial (ClinicalTrials.gov reg. no. NCT01179048) demonstrated a reduced risk of cardiovascular (CV) events for patients with type 2 diabetes who received the glucagon-like peptide 1 receptor agonist liraglutide versus placebo. The mechanisms behind this CV benefit remain unclear. We aimed to identify potential mediators for the CV benefit observed with liraglutide in the LEADER trial.

RESEARCH DESIGN AND METHODS

We performed exploratory analyses to identify potential mediators of the effect of liraglutide on major adverse CV events (MACE; composite of CV death, nonfatal myocardial infarction, or nonfatal stroke) from the following candidates: glycated hemoglobin (HbA_1c), body weight, urinary albumin-to-creatinine ratio (UACR), confirmed hypoglycemia, sulfonylurea use, insulin use, systolic blood pressure, and LDL cholesterol. These candidates were selected as CV risk factors on which liraglutide had an effect in LEADER such that a reduction in CV risk might result. We used two methods based on a Cox proportional hazards model and the new Vansteelandt method designed to use all available information from the mediator and to control for confounding factors.

RESULTS

Analyses using the Cox methods and Vansteelandt method indicated potential mediation by HbA_1c (up to 41% and 83% mediation, respectively) and UACR (up to 29% and 33% mediation, respectively) on the effect of liraglutide on MACE. Mediation effects were small for other candidates.

CONCLUSIONS

These analyses identify HbA_1c and, to a lesser extent, UACR as potential mediators of the CV effects of liraglutide. Whether either is a marker of an unmeasured factor or a true mediator remains a key question that invites further investigation.

Effects of Liraglutide on Cardiovascular Outcomes in Patients With Type 2 Diabetes Mellitus With or Without History of Myocardial Infarction or Stroke

BACKGROUND

The glucagon-like peptide-1 analog liraglutide reduced cardiovascular events and mortality in patients with type 2 diabetes mellitus in the LEADER trial (Liraglutide and Cardiovascular Outcomes in Type 2 Diabetes). In a post hoc analysis, we evaluated the efficacy of liraglutide in those with and without a history of myocardial infarction (MI) and/or stroke.

METHODS

LEADER was a randomized trial of liraglutide (1.8 mg or maximum tolerated dose) versus placebo in 9340 patients with type 2 diabetes mellitus and high cardiovascular risk, with a median follow-up of 3.8 years. The primary outcome was a composite of cardiovascular death, nonfatal MI, or nonfatal stroke (major adverse cardiovascular events). Risk groups in this post hoc analysis were defined by history of MI/stroke, established atherosclerotic cardiovascular disease without MI/stroke, or cardiovascular risk factors alone.

RESULTS

Of the 9340 patients, 3692 (39.5%) had a history of MI/stroke, 3083 (33.0%) had established atherosclerotic cardiovascular disease without MI/stroke, and 2565 (27.5%) had risk factors alone. Major adverse cardiovascular events occurred in 18.8% of patients with a history of MI/stroke (incidence rate, 5.0 per 100 patient-years), 11.6% of patients with established atherosclerotic cardiovascular disease without MI/stroke (incidence rate, 3.0 per 100 patient-years), and 9.8% of patients with cardiovascular risk factors alone (incidence rate, 2.6 per 100 patient-years). Liraglutide reduced major adverse cardiovascular events in patients with a history of MI/stroke (322 of 1865 [17.3%] versus 372 of 1827 patients [20.4%]; hazard ratio, 0.85; 95% CI, 0.73-0.99) and in those with established atherosclerotic cardiovascular disease without MI/stroke (158 of 1538 [10.3%] versus 199 of 1545 patients [12.9%]; hazard ratio, 0.76; 95% CI, 0.62-0.94) compared with placebo. In patients with risk factors alone, the hazard ratio for liraglutide versus placebo was 1.08 (95% CI, 0.84-1.38, P_interaction=0.11). Similar results were seen for secondary outcomes across risk groups.

CONCLUSIONS

In this post hoc analysis of patients with type 2 diabetes mellitus and high cardiovascular risk, liraglutide reduced cardiovascular outcomes both in patients with a history of MI/stroke and in those with established atherosclerotic cardiovascular disease without MI/stroke. The cardiovascular effect appeared neutral in patients with cardiovascular risk factors alone.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01179048.

Duration of diabetes and cardiorenal efficacy of liraglutide and semaglutide: A post hoc analysis of the LEADER and SUSTAIN 6 clinical trials

Cardiovascular risk reduction with liraglutide and semaglutide in patients with type 2 diabetes was demonstrated in the LEADER (ClinicalTrials.gov: NCT01179048) and SUSTAIN 6 (ClinicalTrials.gov: NCT01720446) cardiovascular outcome trials. This post hoc analysis assessed the impact of diabetes duration (<5, 5 to <15, 15 to <25 and ≥25 years at baseline) on cardiorenal efficacy of these human glucagon-like peptide-1 analogues using a Cox proportional hazards model. Proportions of patients in the LEADER trial across diabetes duration strata were 15% (<5 years, n = 1377), 50% (5 to <15 years, n = 4692), 27% (15 to <25 years, n = 2504) and 8% (≥25 years, n = 748); corresponding proportions in the SUSTAIN-6 trial were 13% (<5 years, n = 422), 48% (5 to <15 years, n = 1582), 30% (15 to <25 years, n = 977) and 10% (≥25 years, n = 316). Overall, longer diabetes duration was associated with higher age; higher prevalence of females; history of ischaemic stroke, peripheral arterial disease and insulin use; and inferior renal function. There was an increased frequency of major adverse cardiovascular events (MACE), expanded MACE and nephropathy events with increasing diabetes duration. Liraglutide and semaglutide consistently reduced the risk of cardiorenal outcomes across categories of diabetes duration (P-interaction was not significant for all endpoints analysed).

Decreases in rat extracellular hippocampal glucose concentration associated with cognitive demand during a spatial task

Using in vivo microdialysis, we measured hippocampal extracellular glucose concentrations in rats while they performed spontaneous alternation tests of spatial working memory in one of two mazes. Extracellular glucose levels in the hippocampus decreased by 32% below baseline during the test period on the more complex maze, but by a maximum of 11% on the less complex maze. Comparable decreases were not observed in samples taken from rats tested on the more complex maze but with probes located near but outside of the hippocampus. Systemic glucose fully blocked any decrease in extracellular glucose and enhanced alternation on the more complex maze. These findings suggest that cognitive activity can deplete extracellular glucose in the hippocampus and that exogenous glucose administration reverses the depletion while enhancing task performance.