Performance of the Montreal Consensus in the Diagnosis of Gastroesophageal Reflux Disease in Morbidly Obese Patients

Background Gastroesophageal reflux disease (GERD) has been increasingly recognized in patients with morbid obesity. A recent global evidence-based consensus on GERD has been proposed, but its performance in patients with morbid obesity is unknown. The aim of this study was to assess the performance of the Montreal Consensus in the diagnosis of GERD in morbidly obese patients. Methods Seventy-five consecutive morbidly obese patients underwent GERD symptoms assessment, upper gastrointestinal endoscopy, and ambulatory esophageal pH monitoring “off PPI”. The performance of the Montreal Consensus was determined by comparing two diagnostic algorithms: 1. a gold standard approach in which any GERD symptom and findings from both endoscopy and pH monitoring were taken into account, and 2. the approach with the Montreal Consensus, in which troublesome GERD symptoms and endoscopic findings were considered. Results GERD was found present in 57 patients by applying the gold standard approach. The Montreal Consensus identified 41 of these patients, whereas the remaining 34 patients were classified as “no GERD”. Of these, 16 (47%) showed reflux esophagitis and/or abnormal pH-metry. The Montreal Consensus had an accuracy of 78.7%, sensitivity of 72% (95% CI 59–82%), specificity of 100% (95% CI 82–100%) and negative predictive value of 47% (95% CI 37–57%). Conclusions In morbidly obese patients, the approach with the Montreal Consensus has high specificity and suboptimal sensitivity in the diagnosis of GERD. Its intermediate negative predictive value suggests that complementary investigation might be routine in these patients, particularly in those who do not present with troublesome GERD symptoms. Madalosso and Fornari contributed equally to the study.