Prolonged ambulatory pH monitoring in patients with persistent gastroesophageal reflux disease symptoms: testing while on therapy identifies the need for more aggressive anti-reflux therapy

Am J Gastroenterol. 1996 Oct;91(10):2110-3.


Patients with gastroesophageal reflux disease (GERD) who remain symptomatic despite receiving a moderate dose of a proton pump inhibitor need accurate assessment to determine who will respond to high doses of the drug or even need surgery.

Aim: To determine if prolonged ambulatory pH monitoring performed in patients with persistent symptoms potentially due to GERD while on therapy could predict which patients are likely to benefit from more aggressive anti-reflux therapy.

Methods: Ambulatory pH studies were reviewed for 45 patients with continuing reflux-type symptoms while on 20 mg omeprazole b.i.d. Patients were separated by typical symptoms (heartburn) versus atypical symptoms (chest pain, asthma, hoarseness, cough, throat burning) and for degree of symptom association with episodes of reflux during pH monitoring (symptom index). Control of esophageal acid exposure by omeprazole was defined as distal esophageal pH < 4 < 1.6% total time.

Results: Of these 45 patients, 14 (31%) had acid reflux that was not controlled by omeprazole 20 mg b.i.d. Thirty-six patients had atypical symptoms of GERD, and 10 of these patients had poorly controlled reflux. Of these 10 patients, only one patient responded to omeprazole 20 mg q.i.d. In the other nine patients, omeprazole at the higher dose controlled the reflux (documented by pH monitor), but symptoms persisted with poor association to reflux. Thus, only one out of 36 patients with atypical symptoms had subsequent improvement in symptoms. Nine patients had persistent, typical GERD symptoms, and five of these patients had poorly controlled GER. The three patients with good symptom correlation and poorly controlled reflux all responded to increased omeprazole whereas the two with poor symptom association did not. One patient with good control of reflux but good correlation of the remaining reflux to persistent symptoms also responded symptomatically to 80 mg of omeprazole.

Conclusion: By assessing symptom correlation to reflux episodes and control of reflux by therapy, ambulatory pH monitoring performed in patients with persistent symptoms potentially due to reflux while on therapy gives valuable information concerning further treatment strategies.

MeSH terms

  • Drug Administration Schedule
  • Enzyme Inhibitors / administration & dosage
  • Enzyme Inhibitors / therapeutic use*
  • Esophagus / chemistry
  • Gastroesophageal Reflux / diagnosis*
  • Gastroesophageal Reflux / drug therapy*
  • Humans
  • Hydrogen-Ion Concentration
  • Monitoring, Ambulatory*
  • Omeprazole / administration & dosage
  • Omeprazole / therapeutic use*
  • Proton Pump Inhibitors
  • Time Factors


  • Enzyme Inhibitors
  • Proton Pump Inhibitors
  • Omeprazole