GLP-1 receptor agonists reduce weight in people with schizophrenia, but effect sizes are mostly smaller than in the general population, with six completed trials and three ongoing.
Smaller effectsGLP-1 RA weight loss in schizophrenia vs general population across 6 completed trials
What the researchers found
GLP-1 RAs decrease weight in schizophrenia patients, but effect sizes are mostly smaller than in the general population. Six trials completed, three ongoing, with future directions including dual agonists and early intervention.
Why it matters
Antipsychotic-induced weight gain is a leading cause of medication non-adherence and reduced lifespan in schizophrenia. Effective weight management could improve both physical health and psychiatric outcomes in this vulnerable population.
The numbers in context
3-5 times higher prevalence of diabetes and obesity in schizophrenia patients; 20-year reduced lifespan compared to general population.
How the study worked
Narrative review of all completed and in-progress clinical trials of GLP-1 receptor agonists for weight management in people with schizophrenia.
Who was studied
People with schizophrenia experiencing antipsychotic-induced weight gain
What this study cannot tell us
Narrative review without meta-analysis; most completed trials are small; limited head-to-head comparisons; antipsychotic medication variability across studies; short trial durations; unclear whether weight benefits improve psychiatric outcomes or medication adherence.
How to read the evidence
Moderate evidence from multiple small clinical trials. Consistent direction of effect but smaller magnitude, with larger trials needed.
When this study was published
Published in 2024, with three additional trials ongoing that may provide stronger evidence.
The bigger picture
GLP-1 medications are transforming obesity treatment, but their effects in psychiatric populations may differ due to the complex metabolic effects of antipsychotic medications. Understanding these differences is critical for ensuring this vulnerable population benefits from these breakthroughs.
Questions still open
- Why are GLP-1 RA weight loss effects smaller in schizophrenia — is it the antipsychotics or the disease?
- Could starting GLP-1 RAs simultaneously with antipsychotics prevent weight gain entirely?
- Will dual agonists like tirzepatide show larger effects in this population?
Common questions
Can GLP-1 medications help with weight gain from psychiatric medications?
When should GLP-1 medications be started for people on antipsychotics?
Read the original research
GLP-1 receptor agonists and weight loss in schizophrenia - past, present, and future.
Current opinion in psychiatry, 37(5), 363-369
Citation
Trott, Mike; Arnautovska, Urska; Siskind, Dan. (2024). GLP-1 receptor agonists and weight loss in schizophrenia - past, present, and future.. Current opinion in psychiatry, 37(5), 363-369. https://doi.org/10.1097/YCO.0000000000000952