A Causal Relationship Between Cough and Gastroesophageal Reflux Disease (GERD) has been Established: A Pro/Con Debate
Along with upper airway cough syndrome (formerly, postnasal drip syndrome) and eosinophilic airway inflammation (asthma, nonasthmatic eosinophilic bronchitis), gastroesophageal reflux disease (GERD) is generally considered among the most common etiologies of chronic cough. Indeed, cough management guidelines published by numerous respiratory societies worldwide recommend evaluation and treatment of GERD as an integral component of the diagnostic/therapeutic algorithm for the management of chronic cough. However, a significant number of patients with chronic cough presumed due to GERD do not report improvement despite aggressive acid-suppressive therapy. Some of these refractory cases may be due to the recently appreciated entity of nonacid or weakly acidic reflux. Further contributing to the controversy are recent studies that demonstrate that patients with chronic cough do not have excessive reflux events relative to healthy volunteers. Although a temporal relationship between cough and reflux events has been suggested by studies utilizing impedance-pH monitoring of reflux events and objective cough recording, consensus is lacking in terms of whether this temporal relationship proves a causal link between reflux and cough. The fourth American Cough Conference (New York, June 2013) provided an ideal forum for the debate of this issue between two internationally recognized experts in the field of reflux and chronic cough.
KeywordsGastroesophageal reflux disease Cough pH monitoring Impedance-pH monitoring Proton pump inhibitors Reflux testing Esophagus
Conflict of interest
Dr. Kahrilas is supported by R01 DK56033 and R01 DK092217 from the Public Health Service; Dr. Smith is an inventor on a patent describing novel methods for acoustic cough detection, licensed to a medical device company with which she collaborates to develop a commercial cough monitoring system; Dr. Dicpinigaitis reports no conflicts relevant to the content of this manuscript.
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