Refractory GERD: increased body mass index is associated with persisting acid exposure but not hypersensitive esophagus or functional heartburn.

Objective: To compare the incidence of persistent abnormal acid exposure, hypersensitive esophagus (HE), and functional heartburn (FH) in obese/overweight and normal-weight patients referred for impedance-pH monitoring, because of persisting gastroesophageal reflux disease (GERD) symptoms despite therapy with proton pump inhibitors (PPIs). ΜETHODS: Patients with normal endoscopy and typical GERD symptoms, despite PPI therapy twice daily, underwent 24-h impedance-pH monitoring while on therapy. Distal esophageal acid exposure (% time pH<4) was measured and reflux episodes were classified into acid or nonacid. A positive symptom index was defined when at least 50% of symptom events were preceded by reflux episodes. Patients were categorized as those with persistent abnormal acid exposure, those with HE, and those with FH. The incidence of persistent abnormal acid exposure, HE, and FH between overweight/obese patients (BMI≥25 kg/m) and normal-weight patients (BMI<25 kg/m) was subsequently evaluated.
Results: A total of 246 patients (women: 158, men: 88, increased BMI: 151, normal BMI: 95, mean age 55, range 18-75 years) were included. Persistent abnormal acid exposure was found in 39 patients (increased BMI: 31, normal BMI: 8), HE in 77 patients (increased BMI: 43, normal BMI: 34), and FH in 118 patients (increased BMI: 69, normal BMI: 49). When comparing BMI among all three groups, patients with increased BMI were more likely to have acid reflux than HE or FH (P=0.03).
Conclusion: In patients with GERD symptoms refractory to double-dose PPI therapy, those with increased BMI are more likely to have persistent abnormal acid exposure than HE or FH.