Oesophageal and gastric pH profiles in patients with gastro-oesophageal reflux disease and Barrett's oesophagus treated with proton pump inhibitors

Background: Acid plays a significant role in the development of gastro-oesophageal reflux symptoms and tissue damage. It is generally assumed that acid suppressive therapy with proton pump inhibitors improves or eliminates symptoms of gastro-oesophageal reflux disease by normalizing intra-oesophageal pH. However, the degree of acid suppression induced by proton pump inhibitor therapy in patients with gastro-oesophageal reflux disease and/or Barrett's oesophagus has not been adequately studied. Aim: To assess the efficacy of proton pump inhibitors in normalizing intra-oesophageal and intra-gastric pH in patients with gastro-oesophageal reflux disease with and without Barrett's oesophagus who have been rendered symptom-free by acid-suppressive therapy. Methods: Patients with gastro-oesophageal reflux disease and Barrett's oesophagus were prospectively evaluated by dual sensor 24-h pH monitoring while receiving proton pump inhibitor therapy for complete control of gastro-oesophageal reflux disease symptoms. Analyses and comparisons of intra-oesophageal and intra-gastric pH profiles on therapy were then made. Results: One hundred and ten patients, 98 men and 12 women, with gastro-oesophageal reflux disease (n = 62) and/or Barrett's oesophagus (n = 48), were studied. All tolerated proton pump inhibitors well and were asymptomatic at the time of the study. Thirty-six (58%) patients with gastro-oesophageal reflux disease and 24 (50%) patients with Barrett's oesophagus (P = 0.4) normalized their intra-oesophageal pH profiles on proton pump inhibitors. Compared with patients with gastro-oesophageal reflux disease, patients with Barrett's oesophagus were more likely to have higher degree of pathologic acid reflux despite proton pump inhibitor therapy (DeMeester score 50.5 +/- 8.2 vs. 31.4 +/- 4.6, P = 0.03) and exhibited less intra-gastric acid suppression (% total pH<4.0: 53.9 +/- 2.7 vs. 39.9 +/- 2.6, P =0.0004), particularly supine (% pH<4.0: 62.1 +/- 3.4 vs. 44.8 +/- 3.4, P =0.0006). Conclusions: Gastro-oesophageal reflux disease patients with or without Barrett's oesophagus continue to exhibit pathologic gastro-oesophageal reflux disease and low intra-gastric pH despite proton pump inhibitor therapy that accomplishes complete reflux symptom control. Further, intra-oesophageal and intra-gastric pH control is significantly more difficult to achieve in patients with Barrett's oesophagus. These findings may have significant therapeutic implications.