[Assessment of cough threshold in patients with gastroesophageal reflux disease]

Abstract

The aim of this study was the assessment of citric acid cough threshold in patients with chronic cough due to GERD, confirmed by 24-hour esophageal pH- monitoring, with other reasons of chronic cough excluded. Thirty subjects with chronic cough due to GERD and 15 healthy volunteers underwent cough challenge with doubling concentrations of citric acid using Asthma Provocation System (Jaeger). The cough threshold was defined as the first concentration of citric acid that induced cough. Spirometric parameters (FEV, PEF and FVC) were measured before and 10 minutes after cough challenge in all groups. A day and night cough score diaries (verbal category descriptive score) were completed in all subjects. The cough threshold was significantly lower in GERD patients in comparison with healthy volunteers. In GERD patients the negative correlation was found between day cough score measurements and cough threshold. Citric acid cough challenge did not cause bronchoconstriction or any significant change of spirometric parameters.