Effects of the glucagon-like peptide-1 receptor agonist liraglutide on 24-h ambulatory blood pressure in patients with type 2 diabetes and stable coronary artery disease: a randomized, double-blind, placebo-controlled, crossover study

Glucagon-like peptide-1 receptor agonists modestly reduced blood pressure among patients with and without diabetes mellitus: A meta-analysis and meta-regression

AIM

The cardiovascular benefits provided by glucagon-like peptide-1 receptor agonists (GLP-1RAs) extend beyond weight reduction and glycaemic control. One possible mechanism may relate to blood pressure (BP) reduction. We aim to quantify the BP-lowering effects of GLP1-RAs.

METHODS

A comprehensive database search for placebo-controlled randomized controlled trials on GLP-1RA treatment was conducted until December 2023. Data extraction and quality assessment were carried out, employing a robust statistical analysis using a random effects model to determine outcomes with a mean difference (MD) in mmHg and 95% confidence intervals (CIs). The primary endpoint was the mean difference in systolic BP (SBP) and diastolic BP. Subgroup analyses and meta-regressions were done to account for covariates.

RESULTS

Compared with placebo, GLP-1RAs modestly reduced SBP [semaglutide: MD -3.40 (95% CI -4.22 to -2.59, p < .001); liraglutide: MD -2.61 (95% CI -3.48 to -1.74, p < .001); dulaglutide: MD -1.46 (95% CI -2.20 to -0.72, p < .001); and exenatide: MD -3.36 (95% CI -3.63 to -3.10, p < .001)]. This benefit consistently increased with longer treatment durations. Diastolic BP reduction was only significant in the exenatide group [MD -0.94 (95% CI -1.78 to -0.1), p = .03]. Among semaglutide cohorts, mean changes in glycated haemoglobin and mean changes in body mass index were directly associated with SBP reduction.

CONCLUSION

Patients on GLP-1RA experienced modest SBP lowering compared with placebo. This observed effect was associated with weight/body mass index reduction and better glycaemic control, which suggests that BP-lowering is an indirect effect of GLP-1RA and unlikely to be responsible for the benefits.

The impact of GLP-1 receptor agonist liraglutide on blood pressure profile, hydration, natriuresis in diabetic patients with severely impaired kidney function

Chronic treatment with GLP-1R agonists may moderately lower blood pressure due to increased natriuresis and RAAS inhibition. Short-term effect of these drugs on blood pressure may be opposite and its mechanism remains unclear. We investigated the effect of a single dose of liraglutide on diurnal blood pressure profile, natriuresis, hydration and serum concentration of renin, aldosterone and atrial natriuretic peptide (ANP) in diabetic kidney disease (DKD). 17 patients with eGFR < 30 ml/min/1.73 m2 and 17 with > 60 ml/min/1.73 m2 received in a random order a single subcutaneous dose 1.2 mg liraglutide and placebo with subsequent 24 h blood pressure and natriuresis monitoring. Before and after each medication thoracic fluid index and plasma renin, aldosterone and ANP were also assessed. The blood pressure load in the daytime and nighttime were significantly increased after liraglutide compared to placebo in patients with eGFR < 30 ml/min/1.73 m2. In patients with eGFR > 60 ml/min/1.73 m2 the changes of arterial pressure were comparable, while the morning surge was significantly reduced after liraglutide compared to placebo. After liraglutide 24 h urine sodium excretion increased in both groups vs. placebo (p < 0.001), the effect was greatest in subjects with eGFR > 60 ml/min/1.73 m2. Plasma ANP increased after liraglutide in both groups, most in patients with eGFR < 30 ml/min/1.73 m2 group. Plasma aldosterone (p = 0.013) and thoracic fluid index (p = 0.01) decreased after liraglutide compared to placebo (p = 0.013 and p + 0.01, respectively. Plasma renin concentration remained unchanged. In severe chronic kidney disease liraglutide induces a transient increase of blood pressure due to reduced natriuresis. The natriuretic effect of liraglutide in DKD may be related to increased ANP and decreased aldosterone secretion.

Efficacy and safety of Mazdutide on weight loss among diabetic and non-diabetic patients: a systematic review and meta-analysis of randomized controlled trials

Background

Overweight and obesity are increasing global public health problems. Mazdutide is a new dual agonist drug that can potentially reduce weight and blood glucose levels simultaneously. However, the synthesis of evidence on the efficacy and safety of this drug is scarce. Therefore, this study aimed to synthesize evidence on the efficacy and safety of Mazdutide compared to placebo on weight reduction among adults with and without diabetes.

Methods

We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs). Data were retrieved from six electronic databases: PubMed, Web of Science, Scopus, Cochrane Library, ClinicalTrial.gov, and Google Scholar, and manually searched from the included references. The data were synthesized using a random effect model. This analysis was performed in the R programming language using the Meta package.

Results

A total of seven RCTs involving 680 participants were included in this study. Mazdutide was more effective in reducing body weight (mean difference [MD]= -6.22%, 95% confidence interval [CI]: -8.02% to -4.41%, I2 = 90.0%), systolic blood pressure (MD = -7.57 mmHg, 95% CI: -11.17 to -3.98 mmHg, I2 = 46%), diastolic blood pressure (MD = -2.98 mmHg, 95% CI: -5.74 to -0.22 mmHg, I2 = 56%), total cholesterol (MD = -16.82%, 95% CI: -24.52 to -9.13%, I2 = 61%), triglycerides (MD = -43.29%, 95% CI: -61.57 to -25.01%, I2 = 68%), low-density lipoprotein (MD= -17.07%, 95% CI: -25.54 to -8.60%, I2 = 53%), and high-density lipoprotein (MD = -7.54%, 95% CI: -11.26 to -3.83%, I2 = 0%) than placebo. Mazdutide was associated with reduced hemoglobin A1c (HbA1c) and fasting plasma glucose in participants with type 2 diabetes. In the subgroup and meta-regression analyses, weight reduction was more significant in non-diabetics compared to diabetics, and in those who received a longer treatment duration (24 weeks) than in those on shorter durations (12-20 weeks). Participants who received Mazdutide had a higher risk of transient mild or moderate gastrointestinal side effects.

Conclusion

Mazdutite appears to be effective in weight reduction among patients with and without diabetes, and it has an advantage over other associated comorbidities. However, it was associated with mild or moderate gastrointestinal side effects.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=403859, identifier CRD42023403859.

Effects of GLP-1 receptor agonists on asprosin levels in normal weight or overweight/obesity patients with type 2 diabetes mellitus

Asprosin is a newly identified adipokine with glucose-raising and appetite-enhancing effects which acts differently from the known hepatic glucose utilization pathway. This study investigated changes in serum asprosin levels in normal weight or overweight/obese liraglutide-treated patients with type 2 diabetes (T2DM). This study is a non-randomized, prospective observational study. The metabolic parameters and asprosin levels were compared between 90 people with T2DM and 66 people who had normal glucose tolerance (NGT). During the treatment phase, only T2DM patients were given liraglutide at doses of 0.6 mg/d for the first 2 weeks, 1.2 mg/d for the subsequent 4 weeks, and 1.8 mg/d for the following 16 weeks. T2DM patients were separated into a normal weight group and an overweight/obesity group to compare changes in asprosin and parameters pre- and post-treatment. The T2DM group had significantly higher fasting asprosin and 2h-postprandial asprosin levels than the NGT group (all P < .001). Fasting asprosin and postprandial asprosin positively correlated with BMI, 2hPG, HbA1c, TG, and HOMA-IR, and negatively correlated with HDL-C in both the T2DM and NGT groups. Asprosin levels decreased after liraglutide treatment in both normal and overweight/obesity T2DM groups (all P < .001), with significantly reduced body weight and BMI in overweight/obese T2DM patients (all P < .001). Fasting and postprandial serum asprosin concentrations are higher in T2DM patients compared to normal glucose controls. Fasting and postprandial asprosin positively correlated with BMI, 2hPG, HbA1c, TG, and HOMA-IR and negatively correlated with HDL-C in all participants. Liraglutide lowers asprosin levels in T2DM patients and can reduce weight and BMI in overweight or obese type 2 diabetics.

Cardiovascular effects of incretins - focus on GLP-1 receptor agonists

GLP-1 receptor agonists (GLP-1 RAs) have been used to treat patients with type 2 diabetes since 2005 and have become popular because of the efficacy and durability in relation to glycaemic control in combination with weight loss in most patients. Today in 2022, seven GLP-1 RAs, including oral semaglutide are available for treatment of type 2 diabetes. Since the efficacy in relation to reduction of HbA1c and body weight as well as tolerability and dosing frequency vary between agents, the GLP-1 RAs cannot be considered equal. The short acting lixisenatide showed no cardiovascular benefits, while once daily liraglutide and the weekly agonists, subcutaneous semaglutide, dulaglutide, and efpeglenatide, all lowered the incidence of cardiovascular events. Liraglutide, oral semaglutide and exenatide once weekly also reduced mortality. GLP-1 RAs reduce the progression of diabetic kidney disease. In the 2019 consensus report from EASD/ADA, GLP-1 RAs with demonstrated cardio-renal benefits (liraglutide, semaglutide and dulaglutide) are recommended after metformin to patients with established cardiovascular diseases or multiple cardiovascular risk factors. European Society of Cardiology (ESC) suggests starting with a SGLT-2 inhibitor or a GLP-1 RA in drug naïve patients with type 2 diabetes and atherosclerotic CVD or high CV Risk. However, the results from cardiovascular outcome trials (CVOT) are very heterogeneous suggesting that some GLP-1RA are more suitable to prevent CVD than others. The CVOTs provide a basis upon which individual treatment decisions for patients with T2D and CVD can be made.

Impact of Cotadutide drug on patients with type 2 diabetes mellitus: a systematic review and meta-analysis

BACKGROUND

The food and drug administration approved many drugs to treat diabetes mellitus, but those drugs do not have a noticeable effect on weight management. Recently, glucagon-like peptide 1 agonist known as Cotadutide serve as a potent drug in treating type 2 diabetes by reducing blood glucose levels and body weight indices. This study aimed to explore the safety and efficacy of Cotadutide as a treatment for type 2 diabetes individuals.

METHODS

A comprehensive literature search was done on different databases, including PubMed, Scopus, Web of Science, and Cochrane Library to capture all relevant articles using an established search strategy. The inclusion criteria were randomized controlled trials that assessed the safety and efficacy of Cotadutide versus placebo or any anti-diabetes drugs in patients with type 2 diabetes mellitus and a BMI between 22 kg/m2 and 40 kg/m2. We conducted the analysis using Revman software version 5.4.

RESULTS

We found 663 relevant articles. From which nine studies were included and subjected to qualitative analysis and eight for quantitative analysis. The pooled effect showed that Cotadutide was better than placebo in reducing body weight (kg) (Mean difference (MD) = 3.31, p < 0.00001), glycated hemoglobin (HbA1c) (MD = 0.68, p > 0.00001), glucose area under the plasma concentration curve (AUC [0-4 h]) (MD = 30.15, p < 0.00001), and fasting plasma glucose over time (mg/dl) (MD = 31.31, p < 0.00001).

CONCLUSION

Cotadutide is safe and effective in reducing plasma glucose levels, HbA1c and body weight in individuals with type 2 diabetes.

TRIAL REGISTRATION

The study protocol was registered on PROSPERO (CRD: CRD42021257670 ).

The effect of glucagon-like peptide-1 receptor agonists on 24-hour ambulatory blood pressure: a confirmatory meta-analysis

OBJECTIVE

Hypertension augments overall cardiovascular risk in patients with type 2 diabetes mellitus (T2DM); however, control rates remain suboptimal. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have revolutionized the field of T2DM therapeutic management due to their multiple pleiotropic effects. Therefore, we sought to determine the effect of this class on ambulatory blood pressure monitoring (ABPM), pooling data from relevant randomized controlled trials (RCTs).

METHODS

We searched major electronic databases, namely PubMed and Cochrane Library, along with gray literature sources, for RCTs assessing the effect of various GLP-1RAs on ambulatory BP in patients with T2DM.

RESULTS

We pooled data from seven RCTs in total. GLP-1RA treatment compared to placebo or active control resulted in a nonsignificant decrease in 24-h SBP (mean difference = -1.57 mm Hg; 95% CI,-4.12 to 0.98; I2 = 63%) and in 24-h DBP (mean difference = 1.28 mmHg; 95% CI,-0.31 to 2.87; I2 = 49%). No subgroup differences between the various GLP-1RAs were detected.

CONCLUSION

GLP-1RAs treatment does not influence either systolic or diastolic ambulatory BP in patients with T2DM.

Efficacy and safety of liraglutide in type 2 diabetes mellitus patients complicated with coronary artery disease: A systematic review and meta-analysis of randomized controlled trials

To evaluate the efficacy and safety of liraglutide in patients with Type 2 Diabetes Mellitus (T2DM) complicated with Coronary Artery Disease (CAD), we searched PubMed, Cochrane Library, Embase, China National Knowledge Infrastructure (CNKI), Chinese VIP Information (VIP), Wanfang Database and Chinese Biomedical Literature database (CBM) for relevant randomized controlled trials (RCTs) from inception to 7 October 2020. A total of 18 RCTs including 1557 patients with T2DM complicated with CAD were included. Meta-analysis revealed liraglutide reduced hemoglobin A1c (HbA1c) (WMD = -0.67; 95% CI[-0.94 to -0.39]; P < 0.00001), fasting plasma glucose (FPG) (WMD = -0.80; 95% CI[-1.06 to -0.54]; P < 0.00001) and 2 h plasma glucose (2hPG) (WMD = -1.64; 95% CI[-2.12 to -1.16]; P＜0.00001); improved left ventricular ejection fraction(LVEF) (WMD = 4.79; 95% CI[4.08-5.51]; P < 0.00001), left ventricular end-diastolic diameter (LVEDD) (WMD = -5.70; 95% CI[-6.67 to -4.72]; P＜0.00001), E/A (WMD = 0.13; 95% CI[0.11-0.14]; P < 0.00001) and left ventricular posterior wall thickness (LVPWT) (WMD = -1.86; 95% CI[-2.16 to -1.55]; P < 0.00001); reduced total cholesterol (TC) (WMD = -0.48; 95% CI[-0.56 to -0.39]; P < 0.00001), triglycerides (TG) (WMD = -0.42; 95% CI[-0.59 to -0.26]; P < 0.00001), low-density lipoprotein cholesterol (LDL-C) (WMD = -0.41; 95% CI[-0.55 to -0.26]; P < 0.00001), and increased high-density lipoprotein cholesterol (HDL-C) (WMD = -0.19; 95% CI[0.13-0.24]; P = 0.0005). As for safety assessment, liraglutide did not increase the incidence of hypoglycemia (OR = 0.75, 95% CI[0.32-1.77], P = 0.51) and gastrointestinal (OR = 1.15, 95% CI[0.72-1.85], P = 0.55) events. Consequently, liraglutide had favorable effects on blood glucose, cardiac function, lipid profile and an acceptable safety profile.

Effect of Liraglutide on Cardiometabolic Risk Profile in People with Coronary Artery Disease with or without Type 2 Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Whether liraglutide use improves cardiometabolic risk factors in different subsets of subjects with coronary artery disease (CAD) remains unclear. In a systematic review and meta-analysis, we quantified the effects of liraglutide on cardiometabolic risk profile in subjects with CAD with or without type 2 diabetes mellitus (T2D).

Methods: Online database searches were conducted in PubMed, Scopus, EMBASE, Web of Science, Cochrane library, and Google Scholar from incept up to 15th January 2021. We identified randomized controlled trials (RCTs) assessing the effects of liraglutide compared to placebo on cardiometabolic risk profile. We used the random- or fixed-effect models to pool the weighted mean differences (WMDs) and 95% confidence intervals (CIs).

Results: Out of a total of 7,320 citations, six articles (seven RCTs) with 294 subjects with CAD (mean age, 61.21 years; 19% women) were included. Our findings presented as WMD and 95% CI showed a statistical significant decrease in hemoglobin A1c (HbA1c) [−0.36%; −0.47; −0.26, p < 0.001; I² = 0.0% (with 6 RCTs)], body mass index (BMI) [−0.61 kg/m²; −1.21; −0.01, p = 0.047; I² = 72.2% (with five RCTs)], and waist circumference [−2.41 cm; −3.47; −1.36, p < 0.001; I² = 0.0% (with three RCTs)]. Through a set of subgroup analyses, we found a significant reduction in BMI in CAD patients with T2D [WMD = −1.06; 95% CI, −1.42, −0.70, p < 0.001; I² = 0.0% (with three RCTs)] compared to CAD only patients [WMD = −0.08; 95% CI, −0.45, 0.29, p = 0.66; I² = 0.0% (with two RCTs)] in the liraglutide group compared with the placebo group. No significant changes in heart rate, blood pressure, and lipid profiles were observed.

Conclusions: Among people with established CAD, liraglutide significantly improved HbA1c, BMI, and waist circumference values. The effect of liraglutide on BMI was more robust in individuals with T2D compared to those without.

Patterns of Circadian Variation in 24-Hour Ambulatory Blood Pressure, Heart Rate, and Sympathetic Tone Correlate with Cardiovascular Disease Risk: A Cluster Analysis

To investigate whether specific time series patterns for blood pressure (BP), heart rate (HR), and sympathetic tone are associated with metabolic factors and the 10-year risk of atherosclerotic cardiovascular disease (ASCVD). A total of 989 patients who underwent simultaneous 24-hour ambulatory BP and Holter electrocardiogram monitoring were enrolled. The patients were categorized into sixteen groups according to their circadian patterns using the consensus clustering analysis method. Metabolic factors, including cholesterol profiles and apolipoprotein, were compared. The 10-year ASCVD risk was estimated based on the Framingham risk model. Overall, 16 significant associations were found between the clinical variables and cluster groups. Age was commonly associated with all clusters in systolic BP (SBP), diastolic BP (DBP), HR, and sympathetic tone. Metabolic indicators, including diabetes, body mass index, total cholesterol, high-density lipoprotein, and apolipoprotein, were associated with the four sympathetic tone clusters. In the crude analysis, the ASCVD risk increased incrementally from clusters 1 to 4 across SBP, DBP, HR, and sympathetic tone. After adjustment for multiple variables, however, only sympathetic tone clusters 3 and 4 showed a significantly high proportion of patients at high risk (≥7.5%) of 10-year ASCVD (odds ratio (OR) = 5.90, 95% confidential interval (CI) = 1.27-27.46, and P value = 0.024 and OR = 15.28, 95% CI = 3.59-65.11, and P value < 0.001, respectively). Time series patterns of BP, HR, and sympathetic tone can serve as an indicator of aging. Circadian variations in sympathetic tone can provide prognostic information about patient metabolic profiles and indicate future ASCVD risk.

Liraglutide reduces systolic blood pressure in patients with type 2 diabetes mellitus: A meta-analysis of randomized trials

The antidiabetic effect of liraglutide in patients with type 2 diabetes mellitus has been explored in several trials. We performed this meta-analysis determining the effects of liraglutide on blood pressure in these patients. Three electronic databases (Pubmed, Web of Science, and Cochrane Central) were searched for all published articles evaluating the effects of liraglutide on blood pressure in subjects with type 2 diabetes mellitus. Total 968 patients were included in 10 randomized, double-blind, placebo-controlled trials with a follow-up of 16 ± 9 weeks. Liraglutide 1.8 mg/day reduced systolic blood pressure (weighted mean differences -5.39 (95% confidence interval, -7.26, -3.51) mm Hg, p < .001) and body weight (weighted mean differences -2.07 (95% confidence interval, -2.62, -1.51) kg, p < .001) in patients with type 2 diabetes mellitus. There was no significant difference for changes of diastolic blood pressure between liraglutide 1.8 mg/day and placebo in these patients (weighted mean differences -0.53 (95% confidence interval, -1.96, 0.89) mm Hg, p > .05). The increases of heart rate were greater than placebo in patients treated with liraglutide 1.8 mg/day (weighted mean differences 6.03 (95% confidence interval, 4.78, 7.29) kg, p < .001). There was no significant correlation between reduction of systolic blood pressure and weight loss in patients treated with liraglutide 1.8 mg/day (p = .24). In conclusion, liraglutide reduces systolic blood pressure and body weight in patients with type 2 diabetes mellitus. These data suggest the beneficial effects of liraglutide on cardiovascular protection and may improve prognosis in these patients.

Effect of Hemoglobin A1c Reduction or Weight Reduction on Blood Pressure in Glucagon-Like Peptide-1 Receptor Agonist and Sodium-Glucose Cotransporter-2 Inhibitor Treatment in Type 2 Diabetes Mellitus: A Meta-Analysis

Background Glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium-glucose cotransporter-2 inhibitors (SGLT2is) have shown their beneficial effects on cardiovascular outcomes and multiple cardiovascular risk factors, including hypertension. However, the mechanism of blood pressure (BP)-lowering effects of these agents has not been elucidated. This study aims to evaluate the effect of hemoglobin A1c reduction or body weight reduction with GLP-1RA treatment and SGLT2i treatment on BP changes in patients with type 2 diabetes mellitus. Methods and Results Studies were identified by a search of MEDLINE, EMBASE, and the Cochrane Central Register until June 2019. Meta-regression analysis was performed to evaluate the association between hemoglobin A1c reduction or body weight reduction and changes of BP. A total of 184 trials were included. Both GLP-1RA and SGLT2i led to significant reductions in systolic BP (weighted mean difference, -2.856 and -4.331 mm Hg, respectively; P<0.001 for both) and diastolic BP (weighted mean difference, -0.898 and -2.279 mm Hg, respectively; P<0.001 for both). For both drug classes, hemoglobin A1c reduction was not independently associated with systolic BP reduction or diastolic BP reduction. In GLP-1RA treatment, weight reduction was positively associated with systolic BP reduction and diastolic BP reduction (β=0.821 and β=0.287, respectively; P<0.001 for both). In SGLT2i treatment, weight loss was significantly associated with systolic BP reduction (β=0.820; P=0.001) but was not associated with diastolic BP reduction. Conclusions Treatment with GLP-1RA and SGLT2i led to significant reductions in BP in patients with type 2 diabetes mellitus. Weight reduction was significantly and independently associated with BP reductions in GLP-1RA treatment and SGLT2i treatment.

Glucagon-like peptide-1 receptors in the kidney: impact on renal autoregulation

Glucagon-like peptide-1 (GLP-1) and strategies based on this blood sugar-reducing and appetite-suppressing hormone are used to treat obesity and type 2 diabetes. However, the GLP-1 receptor (GLP-1R) is also present in the kidney, where it influences renal function. The effect of GLP-1 on the kidney varies between humans and rodents. The effect of GLP-1 on kidney function also seems to vary depending on its concentration and the physiological or pathological state of the kidney. In studies with rodents or humans, acute infusion of pharmacological doses of GLP-1 stimulates natriuresis and diuresis. However, the effect on the renal vasculature is less clear. In rodents, GLP-1 infusion increases renal plasma flow and glomerular filtration rate, suggesting renal vasodilation. In humans, only a subset of the study participants exhibits increased renal plasma flow and glomerular filtration rate. Differential status of kidney function and changes in renal vascular resistance of the preglomerular arterioles may account for the different responses of the human study participants. Because renal function in patients with type 2 diabetes is already at risk or compromised, understanding the effects of GLP-1R activation on kidney function in these patients is particularly important. This review examines the distribution of GLP-1R in the kidney and the effects elicited by GLP-1 or GLP-1R agonists. By integrating results from acute and chronic studies in healthy individuals and patients with type 2 diabetes along with those from rodent studies, we provide insight into how GLP-1R activation affects renal function and autoregulation.

Glucagon-like peptide 1 (GLP-1)

BACKGROUND

The glucagon-like peptide-1 (GLP-1) is a multifaceted hormone with broad pharmacological potential. Among the numerous metabolic effects of GLP-1 are the glucose-dependent stimulation of insulin secretion, decrease of gastric emptying, inhibition of food intake, increase of natriuresis and diuresis, and modulation of rodent β-cell proliferation. GLP-1 also has cardio- and neuroprotective effects, decreases inflammation and apoptosis, and has implications for learning and memory, reward behavior, and palatability. Biochemically modified for enhanced potency and sustained action, GLP-1 receptor agonists are successfully in clinical use for the treatment of type-2 diabetes, and several GLP-1-based pharmacotherapies are in clinical evaluation for the treatment of obesity.

SCOPE OF REVIEW

In this review, we provide a detailed overview on the multifaceted nature of GLP-1 and its pharmacology and discuss its therapeutic implications on various diseases.

MAJOR CONCLUSIONS

Since its discovery, GLP-1 has emerged as a pleiotropic hormone with a myriad of metabolic functions that go well beyond its classical identification as an incretin hormone. The numerous beneficial effects of GLP-1 render this hormone an interesting candidate for the development of pharmacotherapies to treat obesity, diabetes, and neurodegenerative disorders.

Searching for optimal blood pressure targets in type 2 diabetic patients with coronary artery disease

BACKGROUND

Controversies exist regarding the optimal blood pressure (BP) level that is safe and provides cardiovascular protection in patients with type 2 diabetes mellitus (T2DM) and coexistent coronary artery disease. Several new glucose-lowering agents have been found to lower BP as well, making the interaction between BP and T2DM even more complex.

METHODS

With the reference to recent literature, this review article describes the potential mechanisms of increased risk of hypertension in T2DM and outlines the possible optimal BP levels based upon recommendations on the management of hypertension by the current guidelines, in combination with our research findings, for type 2 diabetic patients with coronary artery disease.

RESULTS

The development of hypertension in T2DM involves multiple processes, including enhanced sympathetic output, inappropriate activation of renin-angiotensin- aldosterone system, endothelial dysfunction induced through insulin resistance, and abnormal sodium handling by the kidney. Both AGE-RAGE axis and adipokine dysregulation activate intracellular signaling pathways, increase oxidative stress, and aggravate vascular inflammation. Pancreatic β-cell specific microRNAs are implicated in gene expression and diabetic complications. Non-pharmacological intervention with lifestyle changes improves BP control, and anti-hypertensive medications with ACEI/ARB, calcium antagonists, β-blockers, diuretics and new hypoglycemic agent SGLT2 inhibitors are effective to decrease mortality and prevent major adverse cardiovascular events. For hypertensive patients with T2DM and stable coronary artery disease, control of BP < 130/80 mmHg but not < 120/70 mmHg is reasonable, whereas for those with chronic total occlusion or acute coronary syndromes, an ideal BP target may be somewhat higher (< 140/90 mmHg). Caution is advised with aggressive lowering of diastolic BP to a critical threshold (< 60 mmHg).

CONCLUSIONS

Hypertension and T2DM share certain similar aspects of pathophysiology, and BP control should be individualized to minimize adverse events and maximize benefits especially for patients with T2DM and coronary artery disease.

Cardiovascular Effects of Liraglutide

BACKGROUND

Liraglutide is a glucagon-like 1 (GLP-1) agonist approved for treatment of type 2 diabetes and obesity.

OBJECTIVE

To review the cardiovascular effects of liraglutide including macrovascular and microvascular events, its use in heart failure, and its effects on heart rate and blood pressure.

RESULTS

The impact of liraglutide on cardiovascular outcomes was examined in a large welldesigned study published in 2016, the LEADER trial. This study included 9,340 patients with advanced type 2 diabetes and high baseline cardiovascular risk. The primary outcome was the first occurrence of death from cardiovascular causes, non-fatal myocardial infarction, or non-fatal stroke. After a median follow-up of 3.8 years, patients randomized to liraglutide had significant reduction in the composite primary outcome compared to patients randomized to placebo, hazard ratio (HR) 0.87; 95% CI 0.78-0.97. Death from cardiovascular causes was significantly reduced with liraglutide therapy (HR, 0.78; 95% CI 0.66-0.93), as well as death from any cause (HR, 0.85; 95% CI 0.74-0.97). In 2017, the LEADER investigators reported that nephropathy events were significantly lower after liraglutide therapy than placebo (HR 0.78; 95% CI 0.67-0.92), but there was no significant difference in retinopathy events. Meanwhile, other studies suggested that the use of liraglutide may be harmful in patients with severe heart failure, in part due to increase in heart rate.

CONCLUSION

Liraglutide is a useful therapy in patients with advanced type 2 diabetes complicated by cardiovascular disease, except patients with severe heart failure. Further studies are needed to evaluate the long-term effects of liraglutide, and to see whether its beneficial effects extend to patients with type 2 diabetes and low cardiac risk.

Effect of liraglutide on ambulatory blood pressure in patients with hypertension and type 2 diabetes: A randomized, double-blind, placebo-controlled trial

AIMS

To assess the effect of liraglutide on 24-hour ambulatory blood pressure and heart rate in patients with hypertension (pre- and stage 1 hypertension) and inadequately controlled Type 2 diabetes (glycated haemoglobin 7%-10% [53-86 mmol/mol]).

MATERIALS AND METHODS

Eligible patients for this investigator-initiated, parallel-group, randomized, double-blind trial were on stable background antihyperglycaemic therapy excluding insulin, glucagon-like peptide-1 receptor agonists and dipeptidyl-peptidase-4 inhibitors. Participants were centrally randomized in a 1:1 ratio to daily liraglutide 0.6 mg, titrated to 1.2 mg after the first week, or placebo for 5 weeks. The primary outcome was change in 24-hour ambulatory systolic blood pressure (SBP), and secondary outcomes included change in ambulatory diastolic blood pressure (DBP) and heart rate. We also assessed renal sodium handling.

RESULTS

Of 87 patients assessed for eligibility, 62 (66.1% men) with a mean age of 60.2 years were randomized to liraglutide (n = 31) or placebo (n = 31). All participants received background therapy with metformin, whilst 35.5% were treated concomitantly with sulphonylureas and 14.5% with pioglitazone. Compared with placebo, liraglutide reduced 24-hour SBP by -5.73 mm Hg (95% confidence interval [CI] -9.81 to -1.65) and had a neutral effect on 24-hour DBP (mean difference - 1.42 mm Hg; 95% CI -4.25 to 1.40), whilst increasing 24-hour heart rate by 6.16 beats/min (95% CI 3.25 to 9.07). Findings were consistent for daytime and night-time measurements. Liraglutide did not increase urine sodium excretion.

CONCLUSION

Based on 24-hour ambulatory measurements, short-term treatment with liraglutide had a favourable effect on SBP whilst increasing heart rate.

Anti-atherosclerotic effect of incretin mimetics: a meta-analysis of randomized controlled trials

Background: Diabetes is a very common cause of cardiovascular disease, and metformin remains the first-line treatment of diabetes. Many trials were conducted to prove the efficacy and safety of other antidiabetic medication as the best add-on medication. Objectives: We aimed to evaluate the atherosclerotic effect of incretin mimetics in patients with diabetes.Methods: We searched in PubMed, clinicaltrials.gov and Cochrane Library for randomized controlled trials (RCTs) comparing incretin mimetic with conventional treatment. The primary outcome was the change in carotid intima-media thickness (CIMT) at the end of the trials.Results: Five RCTs (n = 1241), the mean age of patients included in the trials is 64.3 ± 11.4. The primary outcome was statistically significant for CIMT improvement in terms of long-term follow-up analysis between the incretin mimetic group and conventional group (mean difference [MD] -0.031; 95% Confidence interval [CI] -0.049 to 0.012; P = 0.001), whereas at short-term follow-up it wasn't (MD -0.004; 95% CI -0.024 to 0.016; P = 0.7) in the overall group of study participants. Additionally, the mean change in body mass index (BMI) (MD 0.064; 95% CI -0.54 to 0.67; P = 0.8), and mean change in systolic blood pressure (MD -0.42; 95% CI -3.2 to 2.3; P = 0.8) or diastolic blood pressure (MD 0.25; 95% CI -1.18 to 1.68; P = 0.7) were not significant.Conclusion: Long-term use of incretin mimetic medication results in significant improvement of atherosclerosis, which leads to fewer vascular events, with no apparent effect on blood pressure or BMI. Further dedicated trials are required to show the superiority of adding these medications to conventional treatment versus placebo.

Lowering Blood Pressure with the Combination of a Sodium-Glucose Cotransporter 2 Inhibitor and a Glucagon-like Peptide-1 Receptor Agonist in Type 2 Diabetic Patients: A Clinical Evidence

INTRODUCTION

Patients with type 2 diabetes mellitus (T2DM) often have numerous cardiovascular risk factors, among which hypertension.

AIM

To evaluate the blood pressure variations among patients treated with a combination of a sodium-glucose cotransporter 2 inhibitor (iSGLT-2) and a glucagon-like peptide-1 receptor agonist (GLP-1ra).

METHODS

We analyze 17 patients treated with this combination to quantify the changes on blood pressure by ambulatory blood pressure monitoring at baseline and at three and 6 months follow-up.

RESULTS

We observed a decrease of HbA1c levels (p = 0.004) at six months follow-up, a decrease in mean 24 h systolic blood pressure [from 124 (11) mmHg to 123 (4.75) mmHg, p = 0.04] and in both, mean waking and sleeping systolic blood pressure, being greater the reduction in the sleeping time [118 (20) mmHg to 111 (20) mmHg, p = 0.004].

CONCLUSION

The effect of a combination therapy of an iSGLT-2 and a GLP-1ra on blood pressure in a real-world setting, may have summative effects especially in SBP.

MEDI0382, a GLP-1 and glucagon receptor dual agonist, in obese or overweight patients with type 2 diabetes: a randomised, controlled, double-blind, ascending dose and phase 2a study

BACKGROUND

Weight loss is often key in the management of obese or overweight patients with type 2 diabetes, yet few treatments for diabetes achieve clinically meaningful weight loss. We aimed to assess the efficacy, tolerability, and safety of treatment with MEDI0382, a balanced glucagon-like peptide-1 and glucagon receptor dual agonist developed to provide glycaemic control and weight loss, in patients with type 2 diabetes.

METHODS

This randomised, placebo-controlled, double-blind, combined multiple-ascending dose (MAD) and phase 2a study was done at 11 study sites (hospitals and contract research organisations) in Germany. We enrolled patients aged 18-65 years with controlled type 2 diabetes (glycated haemoglobin A_1c [HbA_1c] levels of 6·5-8·5% at screening) and a body-mass index between 27 kg/m² and 40 kg/m². An interactive web-response system was used to randomly assign patients to receive MEDI0382 or placebo. Patients were randomly assigned 2:1 in cohorts A-C and 3:1 in cohorts D and E in the MAD portion of the study, and 1:1 in the phase 2a portion. Randomisation was done by a contracted third-party operator who was not involved in the clinical operations of the study. The pharmacists, participants, and study site personnel involved in treating and assessing participants were masked to treatment allocation. Patients received once-daily subcutaneous injections of the study drug at doses of no more than 300 μg for 22 days or less in the MAD portion of the study, and a dose of no more than 200 μg for 41 days or less in the phase 2a portion. The two primary endpoints of the phase 2a portion were the change from baseline to day 41 in glucose area under the curve at 0-4 h (AUC_{0-4 h}) after a mixed-meal tolerance test (MMTT), assessed in all participants who received at least one dose of study drug and whose measurements were taken at baseline and day 41, and change from baseline in bodyweight, assessed in the intention-to-treat (ITT) population. Safety analyses were done in all participants who received any study drug analysed according to the treatment they received. This study is registered with ClinicalTrials.gov, number NCT02548585.

FINDINGS

Patients were recruited between Dec 9, 2015, and Feb 24, 2017. 61 patients were randomly assigned to the MAD part of the study (42 to MEDI0382 and 19 to placebo). 51 patients were randomly assigned to the phase 2a part, of whom 25 were randomly assigned to MEDI0382 and 26 to placebo. In the phase 2a study, three patients in the MEDI0382 group and one in the placebo group discontinued, all as a result of adverse events. 22 (88%) patients in the MEDI0382 group and 25 (96%) in the placebo group received at least one dose and had measurements taken at baseline and day 41. Glucose AUC_{0-4 h} post MMTT decreased significantly with MEDI0382 versus placebo (least squares [LS] mean -32·78% [90% CI -36·98 to -28·57] vs -10·16% [-14·10 to -6·21], and the mean difference was -22·62% [-28·40 to -16·85]; p<0·0001). In the ITT population, reduction in bodyweight was significantly greater with MEDI0382 than with placebo (LS mean -3·84 kg [90% CI -4·55 to -3·12] vs -1·70 kg [-2·40 to -1·01] and mean difference of 2·14 kg [-3·13 to -1·31]; p=0·0008). The proportion of patients who had a treatment-emergent adverse event (TEAE) was similar between treatment groups (22 [88%] of 25 in the MEDI0382 group vs 23 [88%] of 26 in the placebo group); gastrointestinal disorders (18 [72%] vs 13 [40%]) and decreased appetite (five [20%] vs none) occurred more frequently with MEDI0382 than placebo. No participants in the MEDI0382 group had a grade 3 or worse TEAE (vs two [8%] in the placebo group).

INTERPRETATION

MEDI0382 has the potential to deliver clinically meaningful reductions in blood glucose and bodyweight in obese or overweight individuals with type 2 diabetes.

FUNDING

MedImmune.

Effects on repetitive 24-hour ambulatory blood pressure in subjects with type II diabetes randomized to liraglutide or glimepiride treatment both in combination with metformin: a randomized open parallel-group study

In this post hoc study, we aimed to investigate liraglutide treatment on repetitive 24-hour blood pressure (BP) in patients with type II diabetes. Sixty-two individuals with type II diabetes (45 males) were randomized to 1.8 mg liraglutide once daily or 4 mg glimepiride together with 1 g metformin twice daily. Ambulatory 24-hour systolic and diastolic blood pressure (sBP/dBP) was repetitively measured at baseline, 2 weeks, and 18 weeks. Outcomes were evaluated as treatment change from baseline, 2 weeks, and 18 weeks. Baseline clinical characteristics of liraglutide (n = 33) and glimepiride (n = 29) groups were well matched. No statistically significant difference in 24-hour sBP/dBP between three time periods and groups was observed. There was no treatment change for 24-hour sBP at week 2 or after week 18. There was a transient treatment change in 24-hour dBP in the liraglutide group at week 2 (3.2 ± 5.4 vs. -1.2 ± 4.5 mm Hg, P < .01). A treatment change in 24-hour heart rate at week 2 (4.9 ± 6.8 vs. 1.0 ± 6.0 bpm, P = .03) and at week 18 (5.9 ± 7.8 vs. 0.2 ± 6.3 bpm, P < .01) was observed in the liraglutide group. In conclusion, liraglutide treatment did not lower BP. However, a small diurnal variation in dBP without affecting BP variability or nocturnal BP dipping was observed.

Hypertension and Diabetes Mellitus: Coprediction and Time Trajectories

Type 2 diabetes mellitus and hypertension overlap in the population. In many subjects, development of diabetes mellitus is characterized by a relatively rapid increase in plasma glucose values. Whether a similar phenomenon occurs during the development of hypertension is not known. We analyzed the pattern of blood pressure (BP) changes during the development of hypertension in patients with or without diabetes mellitus using data from the MCDS (Mexico City Diabetes Study; a population-based study of diabetes mellitus in Hispanic whites) and in the FOS (Framingham Offspring Study, a community-based study in non-Hispanic whites) during a 7-year follow-up. Diabetes mellitus at baseline was a significant predictor of incident hypertension (in FOS, odds ratio, 3.14; 95% confidence interval, 2.17-4.54) independently of sex, age, body mass index, and familial diabetes mellitus. Conversely, hypertension at baseline was an independent predictor of incident diabetes mellitus (in FOS, odds ratio, 3.33; 95% CI, 2.50-4.44). In >60% of the converters, progression from normotension to hypertension was characterized by a steep increase in BP values, averaging 20 mm Hg for systolic BP within 3.5 years (in MCDS). In comparison with the nonconverters group, hypertension and diabetes mellitus converters shared a metabolic syndrome phenotype (hyperinsulinemia, higher body mass index, waist girth, BP, heart rate and pulse pressure, and dyslipidemia). Overall, results were similar in the 2 ethnic groups. We conclude that (1) development of hypertension and diabetes mellitus track each other over time, (2) transition from normotension to hypertension is characterized by a sharp increase in BP values, and (3) insulin resistance is one common feature of both prediabetes and prehypertension and an antecedent of progression to 2 respective disease states.

The autonomic nervous system and cardiac GLP-1 receptors control heart rate in mice

Objectives

Glucagon-like peptide-1 (GLP-1) is secreted from enteroendocrine cells and exerts a broad number of metabolic actions through activation of a single GLP-1 receptor (GLP-1R). The cardiovascular actions of GLP-1 have garnered increasing attention as GLP-1R agonists are used to treat human subjects with diabetes and obesity that may be at increased risk for development of heart disease. Here we studied mechanisms linking GLP-1R activation to control of heart rate (HR) in mice.

Methods

The actions of GLP-1R agonists were examined on the control of HR in wild type mice (WT) and in mice with cardiomyocyte-selective disruption of the GLP-1R (Glp1r^CM−/−). Complimentary studies examined the effects of GLP-1R agonists in mice co-administered propranolol or atropine. The direct effects of GLP-1R agonism on HR and ventricular developed pressure were examined in isolated perfused mouse hearts ex vivo, and atrial depolarization was quantified in mouse hearts following direct application of liraglutide to perfused atrial preparations ex vivo.

Results

Doses of liraglutide and lixisenatide that were equipotent for acute glucose control rapidly increased HR in WT and Glp1r^CM−/− mice in vivo. The actions of liraglutide to increase HR were more sustained relative to lixisenatide, and diminished in Glp1r^CM−/− mice. The acute chronotropic actions of GLP-1R agonists were attenuated by propranolol but not atropine. Neither native GLP-1 nor lixisenatide increased HR or developed pressure in perfused hearts ex vivo. Moreover, liraglutide had no direct effect on sinoatrial node firing rate in mouse atrial preparations ex vivo. Despite co-localization of HCN4 and GLP-1R in primate hearts, HCN4-directed Cre expression did not attenuate levels of Glp1r mRNA transcripts, but did reduce atrial Gcgr expression in the mouse heart.

Conclusions

GLP-1R agonists increase HR through multiple mechanisms, including regulation of autonomic nervous system function, and activation of the atrial GLP-1R. Surprisingly, the isolated atrial GLP-1R does not transduce a direct chronotropic effect following exposure to GLP-1R agonists in the intact heart, or isolated atrium, ex vivo. Hence, cardiac GLP-1R circuits controlling HR require neural inputs and do not function in a heart-autonomous manner.

•

GLP-1 controls heart rate (HR) through the autonomic nervous system and the cardiac GLP-1R in mice.

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The acute induction of HR by GLP-1R agonists is sensitive to propranolol.

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GLP-1R agonists do not directly increase HR in isolated perfused mouse hearts ex vivo.

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The GLP-1R agonist liraglutide does not directly enhance sinoatrial activity ex vivo.

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GLP-1 does not increase heart rate in a heart autonomous manner.

Long-term Saxagliptin Treatment Improves Endothelial Function but not Pulse Wave Velocity and Intima-Media Thickness in Type 2 Diabetic Patients

INTRODUCTION

Pharmacological inhibition of dipeptidyl-peptidase-4 may represent a promising therapeutic approach for glucose control and vascular protection. No information is available on the effects of saxagliptin (S) on aortic pulse wave velocity, carotid intima-media thickness and flow-mediated dilation (FMD, brachial artery) in diabetes.

AIM

We investigated the long-term effects of S, as add-on therapy to metformin, on the above mentioned variables.

METHODS

In 16 patients with decompensated diabetes aortic pulse wave velocity, carotid intima-media thickness and FMD, office and 24-h ambulatory blood pressure, anthropometric, biochemical and metabolic parameters were measured at baseline and after 6 and 12 months of treatment. A group of 16 compensated diabetics served as controls.

RESULTS

The two groups showed superimposable values of the different parameters, with the exception of glycated hemoglobin, blood glucose significantly (P < 0.05) greater in the S-treated patients. In the S-group glucose metabolism and FMD significantly improved during the follow-up (from 169.3 ± 8 to 157.1 ± 9 mg/dl, P < 0.05, from 7.9 ± 0.1 to 6.9 ± 0.2%, P < 0.001 and from 3.6 ± 0.3 to 7.4 ± 0.8%, respectively P < 0.05). No significant difference was detected in the other parameters, including blood pressure.

CONCLUSIONS

Thus treatment with S added-on to metformin results in beneficial effects on endothelial function, related at least in part to the concomitant improvement in glucose metabolism. This may represent a first step in the chain of events leading to a reduction in the progression of the vascular atherogenic process.