S420 In Esophagogastric Junction Outflow Obstruction, More Severe Lower Esophageal Sphincter Obstruction May Be Associated With a Greater Likelihood of Response to Botulinum Toxin Injection

Abstract

Introduction: Features of manometric esophagogastric junction outflow obstruction (EGJOO) that denote clinical relevance towards symptom generation are unclear. We aimed to test whether lower esophageal sphincter (LES) physiological properties measured on high-resolution manometry (HRM) and functional lumen imaging probe (FLIP) are different in patients with EGJOO based on symptomatic improvement after Botulinum toxin (Botox) therapy. Methods: This was a single-center prospective study conducted over an 18-month period. Adult patients with non-obstructive dysphagia or non-cardiac chest pain who were diagnosed with EGJOO per Chicago Classification 4.0 HRM criteria received treatment with 100 units of Botox to the LES. Patients reported the % improvement in symptoms 2 weeks after Botox injection. Symptomatic response to Botox was denoted by 70% or greater improvement in symptoms. HRM metrics, FLIP indices, and esophageal symptom questionnaires were compared between Botox responders vs. non-responders. Results: Forty-three patients (ages 32-87, 74% female) were included. Symptomatic response to Botox at 2 weeks occurred in 16 (37.2%) patients. Table shows physiologic features based on the Botox response. Although the differences in HRM and FLIP metrics were not significantly different between groups, HRM supine integrated relaxation pressure (IRP) and upright IRP, and the FLIP distensibility index (DI) show a trend towards a higher degree of LES obstruction in the Botox-responsive group. Conclusion: EGJOO which responds to Botox therapy seems to demonstrate a more severe obstructive physiology at the LES. These findings support the CC 4.0 criteria for EGJOO. If results in a larger sample are significant, these findings could support the application of more stringent thresholds (for IRP and DI) for the diagnosis of clinically relevant EGJOO. Table 1. - Clinical Features in EGJOO based on response to LES Botox therapy. Count with % or mean with standard deviation are shown as relevant Botox responders (N = 16) Botox non-responders (N = 27) P value Age [range] 65.3 [45-87] 55.5 [32- 76] 0.01* No. Female (%) 12 (75%) 21 (77.8%) 0.83 BMI (kg/m2) 28.4 (7.9) 31.5 (8.2) 0.23 Narcotic use (%) 4 (25%) 4 (14.8%) 0.41 Supine IRP (mmHg) 25.1 (8.5) 22.2 (5.8) 0.20 Upright IRP (mmHg) 23.8 (15.8) 19.3 (7.5) 0.27 Basal LES (mmHg) 53.3 (18.9) 49.8 (22.9) 0.61 DL (s) 7.3 (2.0) 7.4 (1.6) 0.85 DCI (mmHg-s-cm) 3771.6 (2863.1) 3372.3 (4036.0) 0.73 FLIP EGJ DI (mm2/mmHg) 0.83 (0.43) 1.4 (1.3) 0.11 BEDQ 15.3 (12.0) 19.8 (18.4) 0.42 GERDQ 8.1 (2.9) 9 (3.0) 0.41 Eckardt Score 4.9 (3.0) 4.1 (2.1) 0.28 Abbreviations: BMI – body mass index, Brief Esophageal Dysphagia Questionnaire – BEDQ, DCI – distal contractile integral, DL – distal latency, DI – distensibility index, Eckardt Score – ES, EGJ – esophagogastric junction, FLIP – functional lumen imaging probe, Gastroesophageal Reflux Disease Questionnaire – GERDQ.