Glucagon-Like Peptide-1 Receptor Agonists

Metabolic Dysfunction–Associated Steatotic Liver Disease in Adults: A Review

Author/s: 
Herbert Tilg, Salvatore Petta, Norbert Stefan, Giovanni Targher

Importance Metabolic dysfunction–associated steatotic liver disease (MASLD) includes a range of liver conditions, progressing from isolated steatosis (characterized by fat accumulation in the liver without inflammation) to metabolic dysfunction–associated steatohepatitis (MASH), which involves fat accumulation and inflammation in the liver. The presence of MASLD is associated with increased morbidity and mortality due to liver-related complications, hepatocellular carcinoma, cardiovascular disease, and certain extrahepatic cancers.

Observations The most common chronic liver disease worldwide, MASLD affects approximately 30% to 40% of the general adult population globally (with varying prevalence across continents), including approximately 60% to 70% of individuals with type 2 diabetes and approximately 70% to 80% of those with obesity. It is typically diagnosed based on an ultrasonographic finding of hepatic steatosis, along with at least 1 of 5 features of the metabolic syndrome (abdominal overweight or obesity, prediabetes or type 2 diabetes, hypertension, elevated level of plasma triglycerides, and low level of high-density lipoprotein cholesterol) for women who consume less than 140 g/wk of alcohol (<2 standard drinks/d) and for men who consume less than 210 g/wk (<3 standard drinks/d) and have no other known causes of steatosis such as use of a particular medication (eg, corticosteroids, tamoxifen, or methotrexate), hepatitis C, or iron overload. Other risk factors for MASLD include older age (≥50 years) and male sex (male:female ratio approximately 2). The Fibrosis-4 index (a scoring system incorporating age, serum levels of aspartate aminotransferase and alanine aminotransferase, and platelet count) and vibration-controlled transient elastography (a noninvasive imaging technique) are commonly used to stage hepatic fibrosis in patients with MASLD. Cardiovascular disease is the leading cause of death, followed by certain extrahepatic cancers (primarily gastrointestinal, breast, and gynecologic cancer) and liver-related complications, including cirrhosis, hepatic decompensation (ascites, hepatic encephalopathy, or variceal bleeding), and hepatocellular carcinoma. First-line treatment of MASLD involves behavioral modifications (including hypocaloric low-carbohydrate and low-fat diets, physical exercise, and avoidance of alcohol) and management of type 2 diabetes, obesity, hypertension, and hyperlipidemia. Bariatric surgery should be considered for patients with MASLD and a body mass index greater than 35. Resmetirom (a liver-directed, thyroid hormone receptor β-selective agonist) and subcutaneous semaglutide (a glucagon-like peptide-1 receptor agonist) are conditionally approved by the US Food and Drug Administration (FDA) for the treatment of adults with MASH who have moderate to advanced fibrosis.

Conclusions A highly prevalent condition among adults worldwide, MASLD is associated with liver-related complications, hepatocellular carcinoma, cardiovascular disease, and certain extrahepatic cancers. First-line treatment includes behavioral modifications, including a weight-reducing diet, physical exercise, and avoidance of alcohol. Resmetirom and semaglutide are conditionally FDA-approved medications for the treatment of adults with MASH and moderate to advanced fibrosis.

Efficacy and Safety of GLP-1 RAs in Children and Adolescents With Obesity or Type 2 Diabetes: A Systematic Review and Meta-Analysis

Author/s: 
Pareeta Kotecha, Wenxi Huang, Ya-Yun Yeh

Importance Obesity affects 1 in 5 children and adolescents, increasing the risk of type 2 diabetes (T2D). Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are among the few pharmacotherapy options available for this population, necessitating a comprehensive evaluation of efficacy and safety.

Objective To assess the efficacy and safety of GLP-1 RAs in children and adolescents (<18 years) with obesity, prediabetes, or T2D.

Data Sources A systematic search was conducted in PubMed, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) for randomized clinical trials (RCTs) published from inception until February 28, 2025. Data analysis was completed from January 2025 to April 2025.

Study Selection RCTs comparing GLP-1 RAs to placebo in children and adolescents with obesity, overweight, prediabetes, or T2D with reported safety and efficacy data were included.

Data Extraction and Synthesis Two reviewers independently extracted data on sample size, population, interventions, follow-up, and outcomes. Risk of bias was assessed using version 2 of the Cochrane risk of bias tool (RoB2). Efficacy outcomes (except lipids) were analyzed as estimated treatment differences, lipids as estimated treatment ratios, and safety via rate ratios. A random-effects inverse variance model was used for all outcomes.

Main Outcomes and Measures The primary efficacy outcomes were change in hemoglobin A1c (HbA1c) (in percentage points), fasting glucose (in milligrams per deciliter), body weight (in kilograms), body mass index (BMI, calculated as weight in kilograms divided by height in meters squared), BMI z scores or percentiles, BMI standard deviation score (SDS), lipid outcomes, and blood pressure. Exploratory efficacy outcomes included obstructive sleep apnea and metabolic dysfunction–associated steatohepatitis or metabolic dysfunction–associated steatotic liver disease. Safety outcomes included gastrointestinal adverse effects (GI AEs), infections, hepatobiliary disorders, suicidal ideation or behaviors, depression, hypoglycemia, and adverse event discontinuations.

Results A total of 18 RCTs (11 in obesity, 6 in T2D, and 1 in prediabetes) with 1402 participants (838 GLP-1 RA users and 564 placebo) were included (mean [range] age, 13.7 [6-17] years; 831 female participants (59.3%); median [IQR] treatment duration, 0.51 [0.25-1.00] years). GLP-1 RAs significantly reduced HbA1c (−0.44%; 95% CI, −0.68% to −0.21%), fasting glucose (−9.92 mg/dL; 95% CI, −16.20 to −3.64), body weight (−3.02 kg; 95% CI, −4.98 to −1.06), BMI (−1.45; 95% CI, −2.40 to −0.49), BMI SDS (−0.20; 95% CI, −0.36 to −0.05), BMI percentile (−7.24%; 95% CI, −12.97% to −1.51%), and systolic blood pressure (−2.73 mm Hg; 95% CI, −4.04 to −1.43) and increased GI AE (log[rate ratio] [RR], 0.75). Other AEs, including suicidal ideation or behaviors, showed no significant differences.

Conclusions and Relevance In this systematic review and meta-analysis of 18 trials, GLP-1 RAs significantly improved glycemic, weight, and cardiometabolic outcomes in children and adolescents with T2D or obesity. Available data over a relatively short follow-up suggested suicidal ideation or behaviors were not significantly different, although GI AEs warrant attention in long-term management.

Managing Adverse Effects of Incretin-Based Medications for Obesity

Author/s: 
Robert F Kushner, Jaime P Almandoz, Domenica M Rubino

This JAMA Insights explores optimal strategies for managing the adverse effects associated with incretin-based medications for obesity, including semaglutide and tirzepatide.

Subscribe to Glucagon-Like Peptide-1 Receptor Agonists