Prevalence and Pathophysiology of Gastroesophageal Reflux Disease According to the Lyon Consensus in Patients With Morbid Obesity

Abstract Background: Morbid obesity (MO) is associated with gastroesophageal reflux disease (GERD) through little-known mechanisms. The aim of this study was to assess prevalence and pathophysiology of GERD in patients with MO. Methods: Fifty-one patients with MO selected for bariatric surgery underwent clinical questionnaires, endoscopy, high-resolution manometry and 24-hour-pH-impedance. Patients were classified according to the Lyon Consensus: 1) with GERD (Acid exposure time, AET ≥ 6%), 2) without GERD (AET ≤ 4%), and 3) borderline (AET 4 – 6%). Results: Patients with GERD (21.6%) had more episodes (93.4 ± 47.8 vs 47.1 ± 29.1, p = 0.000), longer duration (39.5 ± 30.6 vs 6.6 ± 6.0 min, p = 0.000), higher proximal involvement (17.4 ± 12.3 vs 5.7 ± 4.9%, p = 0.001) and lower mean nocturnal baseline impedance (MNBI) (1635 ± 1075 vs 2666 ± 1515 Ω, p = 0.035). Manometry found higher prevalence of hiatal hernia in GERD patients (27.3 vs 3.0% type-II and 27.3 vs. 18.2% type-III, p = 0.031) but similar low esophagogastric junction contractile integral (18.6 ± 23.1 vs 32.4 ± 30.5 mmHg·s·cm, p = 0.113) and prevalence of dysmotility (27.3 vs 33.3%, p = 0.510). Esophagitis A-B was found in 7.9% of patients, without differences between groups. Conclusion: Non-erosive GERD is highly prevalent in MO and associated with hiatal hernia, increased number and proximal extent of reflux episodes and low MNBI, important pathophysiologic information for the surgical approach for MO patients.