Improved diagnosis of gastro-oesophageal reflux in patients with unexplained chronic cough

Aliment Pharmacol Ther. 2007 Mar 15;25(6):723-32. doi: 10.1111/j.1365-2036.2007.03255.x.


Background: Symptoms, oesophageal pHmetry and proton pump inhibitor treatment are used for diagnosing gastro-oesophageal reflux-related cough. Weakly acidic reflux is now increasingly associated with reflux symptoms such as regurgitation or chest pain.

Aim: To study the association between weakly acidic reflux and cough in a selected, large group of patients with unexplained chronic cough.

Methods: A total of 100 patients with chronic cough (77 'off' and 23 'on' a proton pump inhibitor) were studied using impedance-pHmetry for reflux detection and manometry for objective cough monitoring. Symptom Association Probability (SAP) Analysis characterized the reflux-cough association.

Results: Acid reflux could be a potential mechanism for cough in 45 patients (with either heartburn, high acid exposure or +SAP for acid reflux). Weakly acidic reflux could be a potential mechanism for cough in 24 patients (with either increased oesophageal volume exposure, increased number of weakly acidic reflux or +SAP for weakly acidic reflux). Reflux could not be identified as a potential mechanism for cough in 31 patients.

Conclusion: A positive association between cough and weakly acidic reflux was found in a significant subgroup of patients with unexplained chronic cough. Impedance-pH-manometry identified patients in whom cough can be related to reflux that would have been disregarded using the standard diagnostic criteria for acid reflux.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Chronic Disease
  • Cough / complications*
  • Electric Impedance
  • Female
  • Gastric Acidity Determination
  • Gastroesophageal Reflux / diagnosis*
  • Gastroesophageal Reflux / etiology
  • Humans
  • Hydrogen-Ion Concentration
  • Male
  • Manometry
  • Middle Aged