Effect of liraglutide on food consumption, appetite sensations and eating behaviours in overweight people with type 1 diabetes

Glucagon-Like Peptide 1 Analogues as Adjunctive Therapy for Patients With Type 1 Diabetes: An Updated Systematic Review and Meta-analysis

CONTEXT

Concomitant obesity is common among patients with type 1 diabetes mellitus (T1DM), yet adjunctive therapy options are scarce.

OBJECTIVE

We assess the efficacy and adverse outcomes of glucagon-like peptide 1 (GLP-1) analogues when used as adjunctive therapy for T1DM.

METHOD

PubMed, EMBASE, Cochrane Central, and Scopus databases were searched for randomized controlled trials up to December 2022. Efficacy outcomes were A1c level, body weight, and total daily insulin (TDI) after ≥12 weeks of GLP-1 therapy. We also assessed 12 different adverse outcomes. Subgroup analysis was done for newly diagnosed or C-peptide positive (C-pos) patients. We report the certainty of evidence based on the GRADE assessment tool.

RESULTS

A total of 24 studies using 4 different GLP-1 analogues with a total of 3377 patients were included. Liraglutide had the most substantial evidence with effect sizes on A1c (-0.09%/mg), weight (-2.2 kg/mg), and TDI (-4.32 IU/mg). Liraglutide dose was the greatest predictor of greater average weight loss and TDI decrease but was associated with higher odds of nausea (OR 6.5; 95% CI, 5.0-8.4) and ketosis (OR 1.8; 95% CI, 1.1-2.8). Odds of severe (OR 0.67; 95% CI, 0.43-1.04) or symptomatic hypoglycemia (OR 0.89; 95% CI, 0.53-1.51) were not significantly elevated. Among C-pos patients, greater A1c decrease (-0.51% vs -0.28%) but similar weight loss and TDI were seen. Effect sizes for exenatide were similar, but studies had higher risk of bias and safety data were sparse.

CONCLUSION

Our meta-analysis supports therapeutic benefits of liraglutide for patients with T1DM mainly for weight loss and insulin dose reduction. Newly diagnosed or C-pos patients do not appear to experience greater weight loss benefits.

Impact of tirzepatide in a patient with type 1 diabetes and obesity: A case report

BACKGROUND

The purpose of this case report is to describe the use of tirzepatide, a glucose-dependent insulinotropic polypeptide/glucagon-like peptide-1 receptor agonist, in a patient with type 1 diabetes mellitus (T1DM) and obesity.

CASE SUMMARY

A 23-year-old female with T1DM since the age of 10 years was referred to an endocrinology clinic for specialized diabetes care with a pharmacist owing to increasing insulin requirements and resistance. At baseline, the patient weighed 195 pounds (86.64 kg), which had increased significantly by approximately 40 pounds in the last year, and had a body mass index of 38 kg/m2 and hemoglobin A1c (HbA1c) level of 7.4%. She used hybrid closed loop insulin pump technology with continuous glucose monitoring in 100% automation mode. The patient used on average 55.4 units of basal insulin and 26.5 units of bolus per day (total daily dose, 81.9 units) with a time in range (TIR) of 31%. The patient was started on tirzepatide 2.5 mg weekly and titrated to 7.5 mg weekly with 4-week dose titrations. After 12 weeks, the patient's TIR had doubled to 61% with improvements in glucose variability, insulin requirements had decreased to 57.6 units per day, HbA1c had decreased to 6.9%, daily carbohydrates had decreased by approximately 24%, and weight had decreased to 188 pounds (-7 lbs).

PRACTICE IMPLICATIONS

With additional studies, tirzepatide may be a safe and effective option for patients with T1DM and obesity to improve glycemic control, reduce insulin requirements, and promote weight loss.

Evaluating the Efficacy and Safety of Long-Acting GLP-1 Receptor Agonists in T1DM Patients

(1) Background: Glucagon-like peptide 1 receptor agonists (GLP-1 RA) are a class of therapeutic agents that mimic the endogenous incretin hormone GLP-1. While this class of agents is not approved for Type 1 Diabetes (T1DM) due to concern of increased diabetic ketoacidosis (DKA) risk, long-acting GLP-1 medications are being commonly prescribed off label for T1DM in clinical practice. Several studies addressed the efficacy and safety of short-acting GLP-1 agonists therapy in patients with T1DM, but the data on long-acting agents are lacking. In our study, we aim to fill in this gap and help healthcare providers in their clinical decision making on the use of these agents for T1DM patients. (2) Methods: We conducted a retrospective chart review of T1DM patients on a long-acting GLP-1 for at least six months. Our retrospective chart review included information starting two years prior to starting GLP-1, and six or more months after starting GLP-1. Parameters collected included HbA1c, 14-day Continuous Glucose Monitor (CGM) and blood glucose (BG) data, and metabolic data (weight, systolic and diastolic blood pressure, and cholesterol levels). Statistical analysis was conducted using paired t-tests on R and Excel with α of 0.05. (3) Results: Our cohort consisted of 54 participants with T1DM on a long-acting GLP-1 (semaglutide, dulaglutide, exenatide extended-release [ER], albiglutide). Mean GLP-1 treatment duration was 23.85 ± 15.46 months. HbA1c values decreased significantly by an average of 0.71% percentage points (%-points, p = 0.002) comparing pre-therapy vs. on GLP-1 treatment. Similarly, for pre-therapy vs. on GLP-1 treatment values, CGM results were significant for increased time in range by 12.15%-points (p = 0.0009) showing a decreased average time in hyperglycemia (BG > 180 mg/dL) by a mean difference of 11.97%-points (p = 0.006), decreased 14-day mean BG by 19 mg/dl (p = 0.01), decreased 14-day BG standard deviation by 8.45 mg/dl (p = 0.01), decreased incidence of DKA hospitalization, and a decrease in weight by 3.16 kg (p = 0.007). (4) Conclusions: As more data emerges on cardiovascular and renal benefits of long acting GLP-1 in type 2 diabetes, there have been no reported outcomes in T1DM. Our study is the first to demonstrate glycemic and metabolic benefits of this class of medication as an adjunct therapy to insulin in T1DM, and safety of its use over an average of 1.5–2 years’ time. This study represents real life experience and the data warrants confirmation by additional prospective studies.

Effect of d-β-Hydroxybutyrate-(R)-1,3 Butanediol on Appetite Regulation in People with Prediabetes

SCOPE

The main aim of the present study is to study the effect of acute ketosis on parameters of appetite regulation in prediabetes.

METHODS AND RESULTS

This is a randomized controlled trial registered under ClinicalTrials.gov identifier NCT03889210. After an overnight fast, 18 adults with prediabetes are assigned to consume a ketone monoester (d-β-hydroxybutyrate-(R)-1,3 butanediol) drink and a placebo drink in cross-over fashion. Blood samples are collected every 30 min, from baseline to 150 min. Paired t test is used to compare the total area under the curve (AUC) for the changes in parameters of appetite regulation (acylated ghrelin, peptide YY [PYY], and hunger) following both drinks. Significant elevation in blood β-hydroxybutyrate from 0.2 to 3.5 mmol L^-1 (p < 0.001) is achieved within 30 min. Acute ketosis does not result in statistically significant differences in the AUCs for ghrelin, PYY, and hunger.

CONCLUSION

Acute ketosis consistently does not affect both objective and subjective parameters of appetite regulation in prediabetes.

Tirzepatide suppresses palatable food intake by selectively reducing preference for fat in rodents

AIM

To investigate the role of glucose-dependent insulinotropic polypeptide receptor (GIPR) agonists alone or combined with glucagon-like peptide-1 receptor (GLP-1R) agonists to regulate palatable food intake and the role of specific macronutrients in these preferences.

METHODS

To understand this regulation, we treated mice and rats on several choice diet paradigms of chow and a palatable food option with individual or dual GIPR and GLP-1R agonists.

RESULTS

In mice, the dual agonist tirzepatide suppressed total caloric intake, while promoting the intake of chow over a high fat/sucrose diet. Surprisingly, GIPR agonism alone did not alter food choice. The food intake shift observed with tirzepatide in wild-type mice was completely absent in GLP-1R knockout mice, suggesting that GIPR signalling does not regulate food preference. Tirzepatide also selectively suppressed the intake of palatable food but not chow in a rat two-diet choice model. This suppression was specific to lipids, as GLP-1R agonist and dual agonist treatment in rats on a choice paradigm assessing individual palatable macronutrients robustly inhibited the intake of Crisco (lipid) without decreasing the intake of a sucrose (carbohydrate) solution.

CONCLUSIONS

Decreasing preference for high-caloric, high-fat foods is a powerful action of GLP-1R and dual GIPR/GLP-1R agonist therapeutics, which may contribute to the weight loss success of these drugs.

Macronutrient intake: Hormonal controls, pathological states, and methodological considerations

A plethora of studies to date has examined the roles of feeding-related peptides in the control of food intake. However, the influence of these peptides on the intake of particular macronutrient constituents of food - carbohydrate, fat, and protein - has not been as extensively addressed in the literature. Here, the roles of several feeding-related peptides in controlling macronutrient intake are reviewed. Next, the relationship between macronutrient intake and diseases including diabetes mellitus, obesity, and eating disorders are examined. Finally, some key considerations in macronutrient intake research are discussed. We hope that this review will shed light onto this underappreciated topic in ingestive behavior research and will help to guide further scientific investigation in this area.

Addressing Clinical and Therapeutic Inertia Through Comprehensive Medication Review

Avoiding clinical and therapeutic inertia, through pharmacist-led medication therapy management, can lead to avoidance of inappropriate medication use and adverse medication events. Clinical and therapeutic inertia are terms that have been used indistinctly. One definition is inertia that appears when clinicians do not initiate or intensify therapy appropriately when therapeutic goals are not reached. Another definition is failure to advance or deintensify treatment, and in a broader sense beyond escalation or deintensification of therapy; definitions include failure to screen, make appropriate referrals, manage risk factors, and complications. Failure of clinicians to address clinical and therapeutic inertia in office or hospital visits can contribute to patients using inappropriate medications, and lead to avoidable serious adverse events. Addressing therapeutic inertia may also be a means to minimize prescription costs and improve quality of life. This case illustrates the importance of identifying and addressing the therapeutic appropriateness of medications for an older person who has been prescribed numerous medications over a long period but now has complaints of dizziness as well as the inability to afford all medications.

Glucagon-like peptide-1 receptor agonists as adjunctive treatment for type 1 diabetes: Renewed opportunities through tailored approaches?

Exogenous insulin has been the mainstay treatment for individuals living with type 1 diabetes (T1D). Although there has been tremendous growth in both pharmacological and technological advancements, insulin monotherapy has proven to be insufficient for maintaining optimal glycaemic targets for most adults with T1D. At present, there is still no breakthrough for the treatment of T1D. Adjunctive pharmacotherapies might therefore complement insulin management to achieve better glycaemic control, while possibly offering additional benefits. Recent interest in re-purposing glucagon-like peptide-1 receptor agonists (GLP-1RAs), a leading antihyperglycaemic medication class approved for type 2 diabetes, has prompted the field to seek extended potential for the T1D population. The adjunctive use of GLP-1RAs has been at the forefront of T1D research, albeit with some conflicting trial findings to date. However, the potential of GLP-1 agonism for T1D may have been underestimated, possibly from missed opportunities or categorized effects. Moreover, some GLP-1RAs have demonstrated extra-pancreatic potential with emerging multi-organ protection involving the heart, kidneys, liver and brain in varied cohorts, which may bode well for the growing T1D profile of comorbid complications. This narrative review aims to summarize and critically appraise the current evidence-based literature from large-scale randomized controlled trials and closed-loop system pilot studies that examined GLP-1RAs as adjunctive therapy for T1D. Furthermore, we outline uncharted opportunities with GLP-1 agonism using versatile approaches in selected T1D populations that may inspire and re-direct future research in this field.

Glucagon-like peptide-1, a matter of taste?

Understanding of gustatory coding helps to predict, and perhaps even modulate the ingestive decision circuitry, especially when eating behaviour becomes dysfunctional. Preclinical research demonstrated that glucagon like peptide 1 (GLP-1) is locally synthesized in taste bud cells in the tongue and that GLP-1 receptor exists on the gustatory nerves in close proximity to GLP-1 containing taste bud cells. In humans, the tongue has not yet been addressed as clinically relevant target for GLP-1 based therapies. The primary aim of the current review was to elaborate on the role of GLP- 1 in mammalian gustatory system, in particular in the perception of sweet. Secondly, we aimed to explore what modulates gustatory coding and whether the GLP-1 based therapies might be involved in regulation of taste perception. We performed a series of PubMed, Medline and Embase databases systemic searches. The Population-Intervention-Comparison-Outcome (PICO) framework was used to identify interventional studies. Based on the available data, GLP-1 is specifically involved in the perception of sweet. Aging, diabetes and obesity are characterized by diminished taste and sweet perception. Calorie restriction and bariatric surgery are associated with a diminished appreciation of sweet food. GLP-1 receptor agonists (RAs) modulate food preference, yet its modulatory potential in gustatory coding is currently unknown. Future studies should explore whether GLP-1 RAs modulate taste perception to the extent that changes of food preference and consumption ensue.

Safety and Efficacy of Glucagon-Like Peptide-1 Receptor Agonists in Children and Adolescents with Obesity: A Meta-Analysis

OBJECTIVES

To determine the weight, body mass index (BMI), cardiometabolic, and gastrointestinal effects of glucagon-like peptide-1 (GLP-1) receptor agonists in children with obesity.

STUDY DESIGN

Web of Science, PubMed/MEDLINE, and Scopus databases from 01/01/1994-01/01/2021 for randomized control trials examining the weight, BMI, cardiometabolic, or gastrointestinal effects of GLP-1 receptor agonists in children and adolescents with obesity. Data were extracted by 2 independent surveyors and a random effects model was applied to meta-analyze generic inverse variance outcomes. Primary outcomes were related to weight and cardiometabolic profile, and secondary outcomes of interest were gastrointestinal-related treatment-emergent adverse events.

RESULTS

Nine studies involving 574 participants were identified, of which 3 involved exenatide and 6 involved liraglutide. GLP-1 receptor agonists use caused a modest reduction in body weight (mean difference [MD] -1.50 [-2.50,-0.50] kg, I² 64%), BMI (MD -1.24 [-1.71,-0.77] kg/m², I² 0%), and BMI z score (MD -0.14 [-0.23,-0.06], I² 43%). Glycemic control was improved in children with proven insulin resistance (glycated hemoglobin A1c MD -1.05 [-1.93,-0.18] %, I² 76%). Although no lipid profile improvements were noted, a modest decrease in systolic blood pressure was detected (MD -2.30 [-4.11,-0.49] mm Hg; I² 0%). Finally, analysis of gastrointestinal-related treatment-emergent adverse events revealed an increased risk of nausea (risk ratio 2.11 [1.44, 3.09]; I² 0%), without significant increases in other gastrointestinal symptoms.

CONCLUSIONS

This meta-analysis indicates that GLP-1 receptor agonists are safe and effective in modestly reducing weight, BMI, glycated hemoglobin A1c, and systolic blood pressure in children and adolescents with obesity in a clinical setting, albeit with increased rates of nausea.

PROSPERO ID

CRD42020195869.

Does intervention with GLP-1 receptor agonist semaglutide modulate perception of sweet taste in women with obesity: study protocol of a randomized, single-blinded, placebo-controlled clinical trial

Background

Preclinical studies demonstrated that glucagon-like peptide 1 (GLP-1) is locally synthesized in taste bud cells and that GLP-1 receptor exists on the gustatory nerves in close proximity to GLP-1-containing taste bud cells. This local paracrine GLP-1 signalling seems to be specifically involved in the perception of sweets. However, the role of GLP-1 in taste perception remains largely unaddressed in clinical studies. Whether any weight-reducing effects of GLP-1 receptor agonists are mediated through the modulation of taste perception is currently unknown.

Methods and analysis

This is an investigator-initiated, randomized single-blind, placebo-controlled clinical trial. We will enrol 30 women with obesity and polycystic ovary syndrome (PCOS). Participants will be randomized in a 1:1 ratio to either semaglutide 1.0 mg or placebo for 16 weeks. The primary endpoints are alteration of transcriptomic profile of tongue tissue as changes in expression level from baseline to follow-up after 16 weeks of treatment, measured by RNA sequencing, and change in taste sensitivity as detected by chemical gustometry. Secondary endpoints include change in neural response to visual food cues and to sweet-tasting substances as assessed by functional MRI, change in body weight, change in fat mass and change in eating behaviour and food intake.

Discussion

This is the first study to investigate the role of semaglutide on taste perception, along with a neural response to visual food cues in reward processing regions. The study may identify the tongue and the taste perception as a novel target for GLP-1 receptor agonists.

Ethics and disseminations

The study has been approved by the Slovene National Medical Ethics Committee and will be conducted in accordance with the Declaration of Helsinki and Good Clinical Practice guidelines. Results will be submitted for publication in an international peer-reviewed scientific journal.

Trial registration

ClinicalTrials.govNCT04263415. Retrospectively registered on 10 February 2020

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05442-y.