Gas-Bloat Syndrome after Magnetic Sphincter Augmentation: Incidence, Risk Factors, and Impact on Surgical Outcomes

Abstract

INTRODUCTION: There is paucity of data on gas-bloat syndrome (GBS) after magnetic sphincter augmentation (MSA). The aim of this study was to identify the incidence, risk factors, and impact of GBS on outcomes after MSA. METHODS: This is a retrospective review of patients who underwent MSA from 2014 to 2021 at our institution. Patients who completed standardized 1-year postoperative questionnaires were included for analysis. GBS was defined as score >3 on the gas-bloat–specific item within the GERD-Health Related Quality of Life questionnaire. Analysis was performed to identify preoperative risk factors for GBS and to assess its impact on surgical outcomes. RESULTS: The final study population consisted of 580 patients. At a mean (SD) follow-up of 11.6 (0.15) months, 88.2% were satisfied with the outcome, 90.9% were free from antisecretory medication, and 74.5% achieved normalization of DeMeester score. Gas-bloat syndrome affected 16.7% of patients and was more common among women (19.1% vs 14.4%, p = 0.048) and patients who reported preoperative bloating (22.0% vs 13.0%, p = 0.005). Smaller magnetic implants increased the incidence of GBS [size (13 and 14): 20.6% vs size (15 to 17): 11.3%, p = 0.003]. Patients with GBS were less satisfied (69.6% vs 91.8%, p < 0.0001). They were more likely to resume antisecretory medication after operation (23.7% vs 6.06%, p < 0.0001), despite no difference in the rate of DeMeester score normalization (74.6% vs 74.5%, p = 1.000). CONCLUSION: Gas-bloat syndrome affects 1 in 6 patients after MSA and significantly diminishes patient satisfaction and freedom from antisecretory medication. Patients with preoperative bloating, women, and those with smaller magnetic implants are at higher risk for GBS.