Time-dependent effect of GLP-1 receptor agonists on cardiovascular benefits: a real-world study

The impact of GLP-1 signalling on the energy metabolism of pancreatic islet β-cells and extrapancreatic tissues

Glucagon-like peptide-1 signalling impacts glucose homeostasis and appetite thereby indirectly affecting substrate availability at the whole-body level. The incretin canonically produces an insulinotropic effect, thereby lowering blood glucose levels by promoting the uptake and inhibiting the production of the sugar by peripheral tissues. Likewise, GLP-1 signalling within the central nervous system reduces the appetite and food intake, whereas its gastric effect delays the absorption of nutrients, thus improving glycaemic control and reducing the risk of postprandial hyperglycaemia. We review the molecular aspects of the GLP-1 signalling, focusing on its impact on intracellular energy metabolism. Whilst the incretin exerts its effects predominantly via a Gs receptor, which decodes the incretin signal into the elevation of intracellular cAMP levels, the downstream signalling cascades within the cell, acting on fast and slow timescales, resulting in an enhancement or an attenuation of glucose catabolism, respectively.

GLP-1 receptor agonists for weight reduction in people living with obesity but without diabetes: a living benefit-harm modelling study

Background

The benefit of Glucagon-like Peptide-1 (GLP-1) receptor agonists (RAs) in weight reduction against potential harms remains unclear. This study aimed at evaluating the benefit-harm balance of initiating GLP-1 RAs versus placebo for weight loss in people living with overweight and obesity but without diabetes.

Methods

We performed benefit-harm balance modelling, which will be updated as new evidence emerges. We searched for randomised controlled trials (RCTs) in PubMed, controlled trials registry, drug approval and regulatory documents, and outcome preference weights as of April 10, 2024. We synthesize data using pairwise meta-analysis to estimate the effect of GLP-1 RAs to inform the benefit-harm balance modelling. We predicted the absolute effects of the positive and negative outcomes over 1 and 2 years of treatment using exponential models. We applied preference weights to the outcomes, ranging from 0 for least concerning to 1.0 for most concerning. We then calculated whether the benefit of achieving 5% and 10% weight loss outweighed the harms on a common scale. The analyses accounted for the statistical uncertainties of treatment effects, preference weights, and outcome risks.

Findings

We included 8 RCTs involving 8847 participants. The pooled average age was 46.7 years, with the majority being women (74%) and people living with obesity (96%). Of 1000 persons treated with GLP-1 RAs for 2 years, 375 (95% confidence interval 352 to 399) achieved a 10% weight loss, and 318 (296 to 339) achieved a 5% weight loss compared to those treated with placebo. Several harm outcomes were more frequent in the GLP-1 RA group, including 41 abdominal pain events per 1000 persons over 2 years (19 to 69), cholelithiasis (8, 1 to 21), constipation (118, 78 to 164), diarrhoea (100, 42 to 173), alopecia (57, 10 to 176), hypoglycaemia (17, 1 to 68), injection site reactions (4, -3 to 19), and vomiting (110, 80 to 145) among others. Achieving a 10% weight loss with GLP-1 RA therapy outweighed the cumulative harms, with a net benefit probability of 0.97 at year 1 and 0.91 at year 2. The absolute net benefit was equivalent to 104 (100 to 112) per 1000 persons achieving a 10% weight loss over 2 years without experiencing any worrisome harm. A 5% weight loss did not show a net benefit, with probabilities of 0.13 and 0.01 at year 1 and year 2, respectively. However, these benefits were sensitive to preference weights, suggesting that even a 5% weight loss could be net beneficial for individuals with less concern about harm outcomes. The net benefit for a 10% weight loss was highest for semaglutide, followed by liraglutide and tirzepatide, with 2-year probabilities of 0.96, 0.72, and 0.60, respectively.

Interpretation

The benefit of GLP-1 RAs exceeded the harms for weight loss in the first 2 years of treatment, yet the net benefit was dependent on individual' treatment goals (10% or 5% weight loss) and willingness to accept harms in pursuit of weight loss. This implies that treatment decisions have to be personalized to individuals to optimize benefits and reduce harms and overuse of treatments. Due to varying evidence, especially regarding harm outcomes across studies, it is necessary to continuously update and monitor the benefit-harm balance of GLP-1 RAs.

Funding

SNSF and LOOP Zurich.

Real-World Use of Oral Semaglutide in Adults with Type 2 Diabetes in the PIONEER REAL Netherlands Multicentre, Prospective, Observational Study

INTRODUCTION

In this phase 4, multicentre, prospective, non-interventional PIONEER REAL Netherlands study, we assessed clinical outcomes associated with once-daily oral semaglutide use in real-world clinical practice in adults living with type 2 diabetes (T2D) naïve to injectable glucose-lowering medication.

METHODS

Participants initiated on oral semaglutide were followed for 34-44 weeks. Change in glycated haemoglobin (HbA1c) from baseline (BL) to end of study (EOS) was the primary endpoint; secondary endpoints included change in body weight (BW) from BL to EOS, the proportion of participants with HbA1c < 7.0% at EOS and the composite endpoints of HbA1c reduction ≥ 1.0%-points with BW reduction ≥ 3% or ≥ 5% at EOS. Treatment satisfaction was assessed using the Diabetes Treatment Satisfaction Questionnaire (DTSQ status/change). Safety was evaluated in all participants who initiated oral semaglutide treatment.

RESULTS

Oral semaglutide was initiated in 187 participants; 94.1% completed the study and 78.6% remained on treatment at EOS. At BL, 54.0% of participants were male, mean age was 58.8 years, mean duration of T2D was 8.7 years and mean body mass index was 35.1 kg/m2; mean HbA1c was 8.6% and mean BW was 103.1 kg. Significant improvements from BL to EOS were observed for HbA1c and BW (estimated change [95% confidence interval]: - 1.16%-points [- 1.48 to - 0.85]; p < 0.0001, and - 5.84 kg [- 6.88 to - 4.80]; p < 0.0001, respectively). At EOS, 47.5% of participants had an HbA1c level < 7.0%; 41.8% and 35.5% of participants achieved composite endpoints of HbA1c reduction ≥ 1.0%-points plus BW reduction ≥ 3% or ≥ 5%, respectively. DTSQ status and change scores improved by 2.1 (p = 0.0003) and 10.8 points (p < 0.0001), respectively. Oral semaglutide was easy or very easy to consume for 81.5% of participants. Adverse events were mostly mild/moderate, with gastrointestinal disorders being the most common.

CONCLUSION

In this real-world population, we reported clinically significant reductions in HbA1c and BW, improved treatment satisfaction and no new safety concerns. A graphical abstract is available with this article.

CLINICAL TRIAL REGISTRATION

NCT04601740.

Real-world sex differences in type 2 diabetes patients treated with GLP-1 receptor agonists

AIMS

To evaluate the determinants of cardiovascular (CV) protection in men and women treated with glucagon-like peptide-1 receptor agonists (GLP1-RA).

METHODS

Retrospective cohort study of 550 patients (43% women), with and without established CV disease, followed at a single center after the first prescription of a GLP1-RA. We analyzed the determinants of major adverse cardiovascular events (MACE) in men and women.

RESULTS

The rate of MACE was similar between sexes. In primary prevention, among men, older age (HR 1.13, 95 % C.I. 1.05-1.22; P = 0.001) and GLP-1 RA withdrawal by time (HR 2.77, 95 % C.I. 1.15-6.68; P = 0.023) increased the HR for MACE. Among women, significant predictors of MACE were diabetes duration (HR 1.05, C.I. 1.01-1.10; P = 0.020), GLP-1 withdrawal by time (HR 2.84, 95 % C.I. 1.13-7.10; P = 0.026) and BMI at GLP-1 RA withdrawal (HR 1.08, 95 % C.I. 1.01-1.15; P = 0.026). For individuals with prior CV disease, the HR for MACE was solely impacted by GLP-1 withdrawal over time in males (HR 2.18, 95 % C.I. 1.10-4.30; P = 0.025) and by older age at GLP-1 RA initiation (HR 1.17, 95 % C.I. 1.03-1.33; P = 0.015) in females.

CONCLUSIONS

Although MACE rates were similar, the factors contributing to MACE differed by sex.

Initiating GLP-1 Therapy in Combination with FreeStyle Libre Provides Greater Benefit Compared with GLP-1 Therapy Alone

Background and Aim: Glucagon-like peptide-1 receptor agonists (GLP-1 RA) therapy provides glycemic benefits to individuals with type 2 diabetes (T2D). However, the effects of GLP-1 RA therapy in combination with FreeStyle Libre systems (FSL) are unknown. This study aimed to compare changes in hemoglobin A1c (HbA1c) between people acquiring GLP-1 with FSL (GLP-1+FSL) versus GLP-1 without FSL (GLP-1). Methods: This real-world study used Optum's de-identified Market Clarity Data, a linked electronic health records (EHR)-claims database, and included adults with T2D and HbA1c ≥8% who acquired their first GLP-1 RA medication between 2018 and 2022. GLP-1+FSL subjects acquired their first FSL within ±30 days of their first GLP-1 acquisition. Cohorts were matched 1:5 on baseline insulin therapy, age, sex, baseline HbA1c, and GLP-1 type. Paired changes in HbA1c were compared between unmatched and matched groups at 6 months. Results: The study included 24,724 adults in the unmatched cohort (GLP-1+FSL, n = 478; GLP-1, n = 24,246). The matched cohort included 478 GLP-1+FSL users and 2,390 GLP-1 users: mean age 53.5 ± 11.8 and 53.5 ± 11.3 years, HbA1c 10.25 ± 1.68% and 10.22 ± 1.69%, respectively. HbA1c reduction was greater in the GLP-1+FSL group compared with the GLP-1 group in the unmatched cohort (-2.43% vs. -1.73%, difference 0.70%, P < 0.001, respectively) and in the matched cohort (-2.43% vs. -2.06%, difference 0.37%, P < 0.001). GLP-1+FSL vs. GLP-1 treatment was associated with greater HbA1c reduction in the intensive insulin (-2.32% vs. -1.50%), nonintensive insulin (-2.50% vs. -1.74%), and noninsulin group (-2.46% vs. -1.78%), as well as in patients using semaglutide (-2.73% vs. -1.92%) and dulaglutide (-2.45% vs. -1.71%) GLP-1 RA, all P < 0.001. Conclusions: Adults with suboptimally controlled T2D, initiating GLP-1 RA with FreeStyle Libre, had greater improvement in HbA1c compared with those treated with GLP-1 RA only. These results suggest an additional glycemic benefit of FSL when used with a GLP-1 RA in T2D treatment.

Oral Semaglutide in Routine Clinical Practice: Characteristics of People with Type 2 Diabetes Started on the Drug and Changes in Their Clinical Parameters after 24 Weeks of Treatment

Background/Objectives: Semaglutide is the unique once-daily oral glucagon-like receptor agonist presently available. Aims of this study were to describe clinical characteristics of patients with type 2 diabetes (T2D) initiating oral semaglutide, to assess its effects on glycemic control, body weight (BW) and its tolerability in routine clinical practice. Methods: Electronic medical records from two Italian diabetes clinics were evaluated. Mean glycated hemoglobin (HbA1c) and BW were assessed in adults with T2D before and 6 months after oral semaglutide prescription. Treatment discontinuation and safety data were reported. Results: A total of 192 patients initiating oral semaglutide (44% female) presented a mean age of 66 years, a diabetes duration of 10 years, HbA1c of 7.9% and a BW of 82.6 kg. Almost 50% of patients were obese. Mean HbA1c and BW changes from baseline to follow up were -0.7% and -2.6 kg, respectively. Greater HbA1c reduction was observed in patients with baseline HbA1c ≥ 8% and with diabetes duration <5 years. The composite endpoint of HbA1c ≤7% and a weight loss ≥5% was achieved in 22.5% of the participants. A total of 40 patients (20.8%) discontinued treatment: 26 because of gastrointestinal adverse events, and 10 due to limited effectiveness in lowering HbA1c and/or BW. Conclusions: In a real clinical setting, patients initiating oral semaglutide showed suboptimal metabolic control, short diabetes duration and obesity; a significant improvement in HbA1c and BW was achieved mainly in patients with a more recent diabetes diagnosis, supporting the use of oral semaglutide in the early phase of the disease.

Underuse of GLP-1 receptor agonists in the management of type 2 diabetes despite a favorable benefit-safety profile

INTRODUCTION

Patients with type 2 diabetes (T2DM) are at high risk of atherosclerotic cardiovascular disease (ASCVD) and cardiovascular death. Cardiovascular protection is a key objective in T2DM.

AREAS COVERED

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have proven their efficacy in reducing major cardiovascular events in high-risk patients with T2DM in placebo-controlled trials, a finding confirmed in observational studies compared with other glucose-lowering agents. Overall, GLP-1RAs have a good safety profile associated with a favorable benefit/risk ratio for the management of T2DM, even if their cost-effectiveness might be questionable. International guidelines recommend GLP-1RAs as preferred glucose-lowering agents in patients with ASCVD and as a valuable alternative in overweight/obese patients with T2DM. However, real-life studies worldwide revealed that only a minority of patients receive a GLP-1RA, despite a positive trend for increased prescriptions in recent years. Surprisingly, however, fewer patients with established ASCVD are treated with these cardioprotective antihyperglycemic agents versus patients without ASCVD.

EXPERT OPINION

The reasons for GLP-1RA underuse in clinical practice are multiple. Multifaceted and coordinated interventions targeting all actors of the health-care system must be implemented to stimulate the adoption of GLP-1RAs as part of routine cardiovascular care among patients with T2DM, especially in those with ASCVD.

The Current and Future Role of Insulin Therapy in the Management of Type 2 Diabetes: A Narrative Review

Early initiation of intensive insulin therapy has been demonstrated to be effective in controlling glycemia and possibly preserving beta-cell function. Innovations in insulin formulations and delivery systems continue. However, we have seen an acceleration in the development of new classes of diabetes medications for individuals with type 2 diabetes and obesity, such as, for example, glucagon-like peptide-1 receptor agonists (GLP-1 RAs). These formulations have been shown to confer significant benefits in achieving good glycemic control with reduced hypoglycemia risk, weight loss, and cardiorenal protection. Therefore, it is reasonable to question whether there is still a role for insulin therapy in the management of type 2 diabetes. However, there are clear limitations inherent to GLP-1 RA therapy, including high rates of suboptimal adherence and treatment discontinuation due to high cost and side effects, which diminish long-term efficacy, and supply issues. In addition, newer formulations have shown improvements in convenience and tolerability, and have been shown to be even more effective when used in conjunction with basal insulin. In this narrative review, we discuss current evidence that supports GLP-1 RA use in combination with insulin therapy and the potential pitfalls of reliance on GLP-1 RAs as a substitute for insulin therapy.

Evidence that tirzepatide protects against diabetes-related cardiac damages

BACKGROUND

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are effective antidiabetic drugs with potential cardiovascular benefits. Despite their well-established role in reducing the risk of major adverse cardiovascular events (MACE), their impact on heart failure (HF) remains unclear. Therefore, our study examined the cardioprotective effects of tirzepatide (TZT), a novel glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) receptor agonist.

METHODS

A three-steps approach was designed: (i) Meta-analysis investigation with the primary objective of assessing major adverse cardiovascular events (MACE) occurrence from major randomized clinical trials.; (ii) TZT effects on a human cardiac AC16 cell line exposed to normal (5 mM) and high (33 mM) glucose concentrations for 7 days. The gene expression and protein levels of primary markers related to cardiac fibrosis, hypertrophy, and calcium modulation were evaluated. (iii) In silico data from bioinformatic analyses for generating an interaction map that delineates the potential mechanism of action of TZT.

RESULTS

Meta-analysis showed a reduced risk for MACE events by TZT therapy (HR was 0.59 (95% CI 0.40-0.79, Heterogeneity: r2 = 0.01, I2 = 23.45%, H2 = 1.31). In the human AC16 cardiac cell line treatment with 100 nM TZT contrasted high glucose (HG) levels increase in the expression of markers associated with fibrosis, hypertrophy, and cell death (p < 0.05 for all investigated markers). Bioinformatics analysis confirmed the interaction between the analyzed markers and the associated pathways found in AC16 cells by which TZT affects apoptosis, fibrosis, and contractility, thus reducing the risk of heart failure.

CONCLUSION

Our findings indicate that TZT has beneficial effects on cardiac cells by positively modulating cardiomyocyte death, fibrosis, and hypertrophy in the presence of high glucose concentrations. This suggests that TZT may reduce the risk of diabetes-related cardiac damage, highlighting its potential as a therapeutic option for heart failure management clinical trials. Our study strongly supports the rationale behind the clinical trials currently underway, the results of which will be further investigated to gain insights into the cardiovascular safety and efficacy of TZT.

Risk of major adverse cardiovascular events and stroke associated with treatment with GLP-1 or the dual GIP/GLP-1 receptor agonist tirzepatide for type 2 diabetes: A systematic review and meta-analysis

INTRODUCTION

Mounting evidence suggests that glucagon-like-peptide-1 receptor-agonists (GLP-1 RAs) attenuate cardiovascular-risk in type-2 diabetes (T2DM). Tirzepatide is the first-in-class, dual glucose-dependent-insulinotropic-polypeptide GIP/GLP-1 RA approved for T2DM.

PATIENTS AND METHODS

A systematic review and meta-analysis of randomized-controlled clinical trials (RCTs) was performed to estimate: (i) the incidence of major adverse cardiovascular events (MACE); and (ii) incidence of stroke, fatal, and nonfatal stroke in T2DM-patients treated with GLP-1 or GIP/GLP-1 RAs (vs placebo).

RESULTS

Thirteen RCTs (9 and 4 on GLP-1 RAs and tirzepatide, respectively) comprising 65,878 T2DM patients were included. Compared to placebo, GLP-1RAs or GIP/GLP-1 RAs reduced MACE (OR: 0.87; 95% CI: 0.81-0.94; p < 0.01; I2 = 37%), all-cause mortality (OR: 0.88; 95% CI: 0.82-0.96; p < 0.01; I2 = 21%) and cardiovascular-mortality (OR: 0.88; 95% CI: 0.80-0.96; p < 0.01; I2 = 14%), without differences between GLP-1 versus GIP/GLP-1 RAs. Additionally, GLP-1 RAs reduced the odds of stroke (OR: 0.84; 95% CI: 0.76-0.93; p < 0.01; I2 = 0%) and nonfatal stroke (OR: 0.85; 95% CI: 0.76-0.94; p < 0.01; I2 = 0%), whereas no association between fatal stroke and GLP-1RAs was uncovered (OR: 0.80; 95% CI: 0.61-1.05; p = 0.105; I2 = 0%). In secondary analyses, GLP-1 RAs prevented ischemic stroke (OR: 0.74; 95% CI: 0.61-0.91; p < 0.01; I2 = 0%) and MACE-recurrence, but not hemorrhagic stroke (OR: 0.92; 95% CI: 0.51-1.66; p = 0.792; I2 = 0%). There was no association between GLP-1RAs or GIP/GLP-1 RAs and fatal or nonfatal myocardial infarction.

DISCUSSION AND CONCLUSION

GLP-1 and GIP/GLP-1 RAs reduce cardiovascular-risk and mortality in T2DM. While there is solid evidence that GLP-1 RAs significantly attenuate the risk of ischemic stroke in T2DM, dedicated RCTs are needed to evaluate the efficacy of novel GIP/GLP-1 RAs for primary and secondary stroke prevention.

Poly-Agonist Pharmacotherapies for Metabolic Diseases: Hopes and New Challenges

The use of glucagon-like peptide-1 (GLP-1) receptor-based multi-agonists in the treatment of type 2 diabetes and obesity holds great promise for improving glycaemic control and weight management. Unimolecular dual and triple agonists targeting multiple gut hormone-related pathways are currently in clinical trials, with recent evidence supporting their efficacy. However, significant knowledge gaps remain regarding the biological mechanisms and potential adverse effects associated with these multi-target agents. The mechanisms underlying the therapeutic efficacy of GLP-1 receptor-based multi-agonists remain somewhat mysterious, and hidden threats may be associated with the use of gut hormone-based polyagonists. In this review, we provide a critical analysis of the benefits and risks associated with the use of these new drugs in the management of obesity and diabetes, while also exploring new potential applications of GLP-1-based pharmacology beyond the field of metabolic disease.

Glucagon-Like Peptide-1 Receptor Agonists for Chronic Weight Management

Rates of obesity have risen over the past few decades. Subsequently, the popularity of the pharmaceutical weight-loss drug market has grown over the past few years to meet growing demand. Among the most commonly prescribed drugs for weight management, many are glucagon-like peptide-1 receptor agonists (GLP-1 agonists) which are also utilized for the management of type 2 diabetes. There is a substantial and growing body of research comparing the efficacy of different clinical trials and examining long-term safety. This literature review examines the rise of off-label prescribing practices in the management of weight, with a focus on GLP-1 agonists. Physicians and patients should be aware of the unique aspects of existing treatment options, the impacts of off-label prescribing, and the effects of these medications. This review emphasizes the importance of informed decision-making, as well as the need for further research to guide future clinical practice.

The role of atherogenic lipoproteins in diabetes: Molecular aspects and clinical significance

Dyslipidaemia plays a prominent role in the genesis of atherosclerotic plaque and the increased cardiovascular risk in diabetes. Macrophages readily take up atherogenic lipoproteins, transforming into foam cells and amplifying vascular damage in the presence of endothelial dysfunction. We discuss the importance of distinct lipoprotein subclasses in atherogenic diabetic dyslipidaemia as well as the effects of novel anti-diabetic agents on lipoprotein fractions and ultimately on cardiovascular risk prevention. In patients with diabetes, lipid abnormalities should be aggressively identified and treated in conjunction with therapeutical agents used to prevent cardiovascular disease. The use of drugs that improve diabetic dyslipidaemia plays a prominent role in conferring cardiovascular benefit in individuals with diabetes.