New miracle drugs for weight loss? What they mean: GLP-1 receptor agonists and how these drugs work to reduce obesity.
A new class of drugs that could change the treatment of obesity and metabolic complications
by Niccolo Maurizi
Obesity is one of the major public health challenges of our time. It is associated with numerous chronic diseases, such as type 2 diabetes, cardiovascular disease, hypertension, and some types of cancer. Despite efforts through diet, exercise, and lifestyle changes, many people find it difficult to lose weight sustainably. In recent years, the advent of new drug therapies has offered new hope. Among these, GLP-1 receptor agonists are particularly noteworthy, revolutionizing the treatment of obesity.
What are GLP-1 receptor agonist drugs?
GLP-1 agonists (glucagon-like peptide-1 receptor agonists) are a class of drugs originally developed for the treatment of type 2 diabetes. GLP-1 is a natural hormone produced by the intestines after meals that helps regulate blood sugar levels by stimulating insulin secretion and reducing glucagon production. Recently, it has been discovered that GLP-1 also has a powerful effect on appetite regulation, reducing hunger and increasing satiety.
Mechanism of action of GLP-1 receptor agonists
GLP-1 receptor agonist drugs help with weight loss by acting on several mechanisms:
- Appetite reduction: They act on the hunger centers in the brain, leading to a decrease in the sensation of hunger and the desire for food.
- Slowing gastric emptying: They slow down digestion, increasing the feeling of fullness after meals and contributing to a reduction in caloric intake.
- Improved metabolism: They help better control blood sugar, reduce insulin levels and improve metabolic efficiency, promoting weight loss.
Efficacy demonstrated in clinical studies
Clinical trials have shown that GLP-1 agonist drugs, such as liraglutide and semaglutide, can lead to significant weight loss. For example, in the STEP 1 study published in the New England Journal of Medicine in 2021, participants treated with semaglutide once weekly lost an average of nearly 15% of their initial body weight.
Additional benefits of GLP-1 receptor agonist drugs
In addition to weight loss, GLP-1 agonists have demonstrated additional benefits:
- Improved blood sugar control, important for preventing or treating type 2 diabetes;
- Reduction of blood pressure and improvement of cholesterol levels;
- Reduction of cardiovascular risk, as confirmed by some clinical studies;
- Potential protective effects on the liver, reducing the risk of non-alcoholic fatty liver disease (non-alcoholic fatty liver).
Who are these drugs intended for?
These drugs are indicated for adults with obesity (body mass index ≥30) or overweight (body mass index ≥27) with at least one related complication, such as type 2 diabetes, hypertension or dyslipidemia. It is important that the treatment is always prescribed and followed by a specialist doctor, and inserted into a global program that includes a balanced diet, increased physical activity and behavioral changes.
Side effects and risks
Like all medications, GLP-1 agonists can cause side effects. The most common are gastrointestinal and include nausea, vomiting, diarrhea, and constipation, but none are severe. These symptoms tend to be more intense at the beginning of therapy and subside over time. In rare cases, more serious problems, such as pancreatitis or gallbladder problems, have been reported, which is why careful medical monitoring is essential.
Use in patients with cardiomyopathy
In recent years, it has emerged that GLP-1 agonists may also have positive effects in patients with heart failure. Some studies suggest that these drugs can improve cardiac function, particularly in patients with heart failure with preserved ejection fraction. In addition, weight loss, improved metabolic control, and reduced inflammation help to lighten the load on the heart, improving the functional capacity of patients.
GLP-1 agonists and hypertrophic cardiomyopathy
Regarding hypertrophic cardiomyopathy, data are still limited. However, as it is a condition in which the heart is thickened and works harder, the weight reduction and improved metabolism promoted by GLP-1 agonists could theoretically alleviate the hemodynamic burden, especially in those with outflow tract obstruction, although caution and close specialist supervision are required. In general, the use of GLP-1 agonists in patients with heart failure must be carefully evaluated on a case-by-case basis, considering the individual clinical profile and possible contraindications.
A new weapon in the fight against obesity
GLP-1 agonists represent a new weapon in the fight against obesity, offering for the first time an effective pharmacological therapy that approaches the results achieved with bariatric surgery, but without the same risks. Their use could radically change the way obesity is managed in the coming years. However, it is important to remember that medications alone are not enough. To achieve lasting results, they must be combined with lifestyle changes and adequate psychological support.
Conclusion
The arrival of GLP-1 agonists marks a turning point in obesity management. When combined with proper nutrition, physical activity, and medical support, these drugs can significantly improve body weight and overall health, offering new hope to millions of people. The road to wellness is made of small steps, and today, thanks to GLP-1 agonist drugs, the process can be less arduous and more effective. Obesity: a huge challenge, but now more manageable!
References
1. Wilding JPH, Batterham RL “Once-Weekly Semaglutide in Adults with Overweight or Obesity,” New England Journal of Medicine, 2021; 384:989-1002.
2. Kushner RF, Calanna S., Davies M. “Pharmacological Management of Obesity: An Endocrine Society Clinical Practice Guideline,” The Journal of Clinical Endocrinology & Metabolism, 2022.
3. Pi-Sunyer X. “The Medical Risks of Obesity,” Obesity Surgery, 2002; 12(Suppl 1): 6S–11S.
2. Kushner RF, Calanna S., Davies M. “Pharmacological Management of Obesity: An Endocrine Society Clinical Practice Guideline,” The Journal of Clinical Endocrinology & Metabolism, 2022.
3. Pi-Sunyer X. “The Medical Risks of Obesity,” Obesity Surgery, 2002; 12(Suppl 1): 6S–11S.
Cardiologist, head of the Cardiomyopathy outpatient clinic at the CHUV in Lausanne
