Minimally Invasive Approaches to Obesity: Advances in Bariatric Endoscopy
Obesity is a global health problem associated with substantial socioeconomic costs. Not all patients benefit from pharmacological or surgical therapies, and innovative endoscopic bariatric interventions are increasingly emerging as effective, less invasive options for treating obesity and its comorbidities.#
Obesity and Its Therapeutic Challenges
The prevalence of obesity (BMI > 30 kg/m²) has risen dramatically worldwide, nearly tripling since 1980. In Europe, around 60% of adults and one-third of children are overweight or obese. In Switzerland, approximately 42% of adults are overweight and 11% obese. This trend is accompanied by a significant increase in comorbidities such as type 2 diabetes, cardiovascular disease, obstructive sleep apnea, and metabolic dysfunction–associated steatotic liver disease (MASLD).
Conservative approaches – including dietary, physical activity, and behavioral interventions – rarely achieve sustained weight loss. Pharmacological therapies, particularly GLP-1 receptor agonists such as liraglutide and semaglutide, have shown substantial efficacy, inducing weight loss of approximately 8–14% within one year. The dual GLP-1/GIP agonist tirzepatide can achieve reductions of up to 20%. However, gastrointestinal side effects are common, long-term safety data remain limited, and weight regain after discontinuation is frequent. In addition, the costs of long-term therapy are considerable.
Bariatric surgery remains the gold standard for durable weight loss and reduction of comorbidities and mortality. Procedures such as Roux-en-Y gastric bypass and sleeve gastrectomy achieve long-term weight loss of 25–30%. Nevertheless, only a small proportion of eligible patients undergo surgery due to limited access, concerns about risks, costs, and lack of awareness.
Development of Endoscopic Bariatric Therapy
Bariatric endoscopy has evolved into a minimally invasive and potentially reversible treatment option between pharmacotherapy and surgery. While initially limited to managing complications after bariatric surgery, endoscopy now includes effective primary interventions. Earlier techniques such as gastric balloons or the EndoBarrier® system showed limited long-term success due to modest efficacy or complications.
Endoscopic Sleeve Gastroplasty
The development of endoscopic suturing systems such as OverStitch™ has enabled procedures like endoscopic sleeve gastroplasty (ESG) and POSE-2. These techniques reduce gastric volume by 70–80% through full-thickness sutures along the greater curvature while preserving the fundus. This results in both gastric restriction and delayed gastric emptying, enhancing satiety.
Clinical studies demonstrate that ESG achieves approximately 15–16.5% total body weight loss at 12 months, corresponding to 50–70% excess weight loss. Significant improvements in metabolic comorbidities, including diabetes, hypertension, dyslipidemia, and MASLD, have been observed. Similar results are reported for POSE-2.
Although weight loss is slightly less than with surgery, ESG is associated with a markedly lower rate of serious complications (<2%). Mild adverse events such as nausea or abdominal discomfort are usually transient. Importantly, the risk of gastroesophageal reflux disease is substantially lower compared to sleeve gastrectomy. Long-term data confirm sustained weight loss of around 16% at five years.
Combination strategies appear promising: ESG combined with pharmacotherapy (e.g., liraglutide) can further enhance weight loss outcomes. ESG also serves as a “bridge to surgery” in high-risk or super-obese patients (BMI > 50 kg/m²).
Endoscopic Revision After Bariatric Surgery
Weight regain or insufficient weight loss after bariatric surgery is common and may result from behavioral or anatomical factors such as dilation of the gastric pouch or anastomosis. As surgical revisions carry increased risks, endoscopic approaches offer effective alternatives.
Transoral outlet reduction (TORe) reduces a dilated gastrojejunal anastomosis after gastric bypass to restore restriction. Randomized data demonstrate modest but significant weight loss, and TORe is particularly effective in treating dumping syndrome, with sustained symptom resolution in the majority of patients.
Revisional ESG (R-ESG) allows reduction of a dilated sleeve gastrectomy, achieving clinically meaningful weight loss in over half of patients. Both TORe and R-ESG are safe, minimally invasive, and repeatable procedures.
Future Perspectives
Technological innovations continue to advance the field. Automated suturing systems such as EndoZip™ may simplify procedures and reduce operator dependency, while maintaining efficacy and safety. Another emerging approach is endoscopic fundus ablation using hybrid argon plasma coagulation, targeting ghrelin-producing cells to reduce hunger and induce weight loss.
Future strategies will likely focus on combination therapies – integrating endoscopic procedures with pharmacological treatments – to achieve additive effects and potentially outcomes comparable to bariatric surgery.
Conclusion
Bariatric endoscopy fills an important therapeutic gap between conservative, pharmacological, and surgical treatments. It provides an effective, safe, and increasingly standardized option for patients with obesity and its comorbidities. In Switzerland, specialized SMOB-accredited centers with interdisciplinary expertise offer optimal conditions for implementing these therapies and achieving sustainable weight reduction.
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