Esophageal Acid Exposure on Proton Pump Inhibitors in Unselected Asymptomatic Gastroesophageal Reflux Disease Patients

BACKGROUND AND AIM: Efficacy of proton pump inhibitors (PPIs) on symptoms of gastroesophageal reflux (GER) is supposed to result from normalization of esophageal acid exposure; however, recent data in selected severe patients have challenged this concept. The aim of the study was to investigate 24-hour esophagogastric pH in unselected patients with GER disease in symptomatic remission during PPIs. METHODS: Thirty of the 31 consecutive patients with heartburn enrolled achieved adequate symptom control (<or=1 heartburn episode/wk) on PPIs o.d. (n=22) or b.d. (n=8); 3 refused pH monitoring, thus 27 tracings were analyzed. RESULTS: Medians (Interquartile Range); Intragastric tracings showed a wide range of inhibition of acid secretion, 61.2% (49.7% to 80.2%) time at pH>4, nocturnal acid breakthrough being shorter (P=0.03) on PPIs b.d. compared with PPIs o.d., 125 minutes (90 to 247) versus 253 minutes (210 to 340). Esophageal acid exposure was 3.3% (1.4% to 7.9%) time at pH<4, 9 patients having increased exposure (ie, >5.5%), 7 of whom on PPIs o.d. Patients with increased acid GER on PPIs had a higher prevalence of esophagitis (67% vs. 22%, P<0.05) and hiatus hernia (78% vs. 39%, P<0.1) at endoscopy off PPIs. CONCLUSIONS: One third of unselected patients with GER disease asymptomatic on PPIs have an increased esophageal acid exposure, especially if their PPI is administered o.d.