Gastroesophageal reflux and chronic cough: which comes first?

We evaluated the relationship between gastroesophageal (GE) reflux and chronic cough using prolonged pH monitoring and the standard acid reflux study in a retrospective case review. Ten patients were referred to our clinical esophageal laboratory for prolonged pH monitoring to determine whether GE reflux was the cause of chronic cough. In addition, we report one patient referred for a standard acid reflux test as a clear example of spontaneous cough inducing GE reflux. Of the 10 patients having prolonged pH monitoring, 182 of 221 (80.9 +/- 4.6%) of cough episodes had no correlation with GE reflux (p = 0.0001). Of those cough episodes that appeared to be related to GE reflux, 27 of 39 (69.2 +/- 11.7%) occurred before GE reflux and 12/39 (30.8 +/- 10.3%) occurred after GE reflux (p = 0.06). In the single patient GE reflux after spontaneous cough occurred five of seven times during a standard acid reflux test. In our series, cough and reflux were not related in the majority of episodes. Where there was a relationship, it appeared that the cough preceded GE reflux twice as often as reflux preceded cough. We conclude that GE reflux does not appear to be a frequent cause of chronic cough.