BACKGROUND: Preoperative treatment with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) before bariatric surgery has not been studied. Therefore, we investigated the impact of neoadjuvant treatment with GLP-1 RAs on weight loss and postoperative outcomes in patients who underwent sleeve gastrectomy for severe obesity.
METHOD: A retrospective single-center study was conducted between January 2022 and December 2023. Patients with morbid obesity who were treated preoperatively with a GLP-1 RA (GLP-1 group) were matched with patients who were not preoperatively treated with a GLP-1 RA (No GLP-1 group) using propensity scores calculated according to age and body mass index (BMI). Between-group differences in demographics, comorbidities, surgical parameters, complications, weight loss, and comorbidity outcomes were analyzed.
RESULTS: Fourteen patients were included in the GLP-1 group and matched with 28 controls (1:2 ratio). Preoperative weight loss was significantly greater in the GLP-1 group (7.8 ± 6.8 kg) than in the control group (0.2 ± 4.5 kg), with a mean difference of + 7.54 kg (95% CI: [3.47;11.6], p = 0.001, Cohen's d = 1.41). Mixed-effects ANOVA revealed a significant effect of time, with progressive BMI reduction in both groups (p = 0.019), no main effect of group (p = 0.080), and no group-time interaction (p = 0.972), indicating similar BMI trajectories throughout the perioperative period and no between-group difference at 12 months. Postoperative vomiting occurred in 21.4% of patients in the GLP-1 group versus 0% in the No GLP-1 group (p = 0.031). No significant differences in surgical parameters or the comorbidity resolution rate at one year were found.
CONCLUSION: Neoadjuvant GLP-1 RA treatment increased preoperative weight loss before sleeve gastrectomy, but the benefit was not sustained postoperatively. Preoperative GLP-1 RA use could be considered to optimize surgical preparation, but further data regarding postoperative outcomes and long-term weight benefits are needed.
