Background: Obesity is a disease that is highly prevalent in Brazil, and the associated comorbidities represent a major global public health challenge. Botulinum toxin type A (BTX-A) is a potent neurotoxin and inhibitor of gastric smooth muscle activity. In theory, BTX-A administration should promote early satiety and weight loss because it delays gastric emptying by inhibiting acetylcholine-mediated peristalsis, which is primarily responsible for gastric motility. Because results in the literature are discrepant, the efficacy of intragastric injections of BTX-A as a primary treatment for obesity remains unknown. The objective of this prospective, double-blind, single-center randomized study was to evaluate the effects of endoscopic ultrasound-guided intragastric BTX-A injections, as a bridge to bariatric surgery, in super-obese patients.
Methods: Thirty-two super-obese patients were randomized to one of two groups: BTX-A, in which 200 units of BTX-A were injected into the gastric antrum and body; and control, in which the same injections were performed with 0.9% saline. Weight, body mass index (BMI), and loss of excess weight were measured monthly over a 6-month period. Gastric emptying scintigraphy was performed before and after the procedure.
Results: The patients in both groups showed significant weight loss over the course of the study (p < 0.001). There were no statistically significant differences between the groups regarding weight loss, excess weight, total loss of excess weight, total weight loss, or change in BMI.
Conclusions: Intragastric injection of BTX-A does not appear to be an effective method of achieving preoperative weight loss in super-obese patients.
Keywords: Botulinum toxins; Gastric emptying; Obesity; US endoscopy.