Using Botulinum Toxin for the Treatment of Gastroparesis (GP) Post Gastric Peroral Endoscopic Myotomy (GPOEM)

Abstract

Introduction/Background: Gastroparesis (GP) is a motility disorder that causes delayed gastric emptying, leading to significant morbidity and deterioration of quality of life. Gastric peroral endoscopic myotomy (G-POEM) is a minimally invasive procedure targeting the pyloric sphincter, which has shown efficacy in managing refractory GP. However, not all patients respond equally to G-POEM. Botulinum toxin (Botox) injection into the pylorus may help predict clinical success by identifying responders who would benefit most from G-POEM. Study objective/Hypothesis: The objective of this study was to evaluate the impact of pre-G-POEM botulinum toxin (Botox) injections on improving quality of life (QoL) and symptom severity in patients with gastroparesis (GP). By identifying patients who respond to Botox therapy, we aim to optimize patient selection for G-POEM and maximize the procedure's impact on overall well-being and social functioning. Methods: This retrospective cohort study included 124 GP patients (median age: 50) treated with G-POEM at a single tertiary care center between February 2018 and November 2022. Patients received Botox injections pre-G-POEM and were assessed for symptom severity (Gastroparesis Cardinal Symptom Index [GCSI]), QoL, and social functioning at baseline and follow-up intervals (1, 3, 6, 12, 24, 36, and 48 months). Clinical success was defined as a ≥1-point reduction in GCSI score. Comparative analyses between Botox responders and non-responders were performed, along with quality-of-life assessments using validated scales (e.g., SF-36). Results: Significant short- and intermediate-term improvements were observed in GCSI scores, QoL, and social functioning for Botox responders. GCSI improvement was higher among responders at 3 months post-G-POEM (0.38 vs. 0.03; p < 0.05). Clinical success rates were greater for patients who demonstrated initial improvement with Botox therapy. Overall QoL metrics, including physical and social functioning, were consistently higher among responders across all follow-up intervals. At the 48-month follow-up, 64% of patients demonstrated sustained clinical success, with Botox responders showing the most substantial improvements. Limitations included loss to follow-up and limited data beyond 48 months; however, clinical success at the 1-year mark and beyond was not statistically insignificant, underscoring the potential durability of QoL and symptom improvements over time. Conclusions: Pre-G-POEM Botox injection is a valuable predictive tool for identifying GP patients likely to benefit from G-POEM, resulting in better symptom management, QoL, and clinical success. These findings suggest that incorporating Botox injection prior to G-POEM may optimize patient selection and procedural outcomes. However, clinical success at 1 year and beyond was not statistically proven, highlighting the need for further research to solidify these findings and confirm long-term efficacy. Further studies with larger sample sizes and longer follow-up periods are needed to validate these results.