Smith, John A.

Abstract Purpose: Gastro-oesophageal reflux disease (GORD) is commonly thought to play an important role in chronic cough and patients are often empirically treated with acid suppression therapy. We sought to investigate the response rate to acid suppression treatment in patients with and without heartburn attending two specialist cough clinics. Methods: A retrospective review of 558 consecutive patients referred to two specialist cough clinics was performed (UK and US). Patients who were treated with acid suppression were included and their documented response to treatment collected. Binary logistic regression was used to ascertain the value of reported heartburn in predicting the response of chronic cough to acid suppression therapy. Results: Of 558 consecutive referrals, 238 patients were excluded due to missing data or cough duration of <8weeks. The remaining 320 patients were predominantly female (76%), mean age 61yrs (±13), 96.8% non-smokers, with chronic cough for 36 (18-117) months. Of 72 patients with heartburn, 20 (28%) noted improvement in their cough with acid suppression, whereas of 248 without heartburn, only 35 (14%) responded. Patients reporting heartburn were 2.7 (95% C.I. 1.3-5.6) times more likely to respond to acid suppression therapy (p=0.007).Conclusion: In specialist cough clinics, few patients report a response of their chronic cough to acid suppression therapy. Nonetheless, heartburn is a useful predictor substantially increasing the likelihood of benefit.

AbstractBackgroundGastroesophageal reflux plays an important role in chronic cough (CC). Whether disturbed esophageal motility contributes to increased esophageal reflux exposure or interferes with swallowed bolus clearance is unclear. This study used high resolution esophageal manometry and impedance (HRIM) together with Chicago Classification, and 24‐h impedance pH (MII/pH) to address these questions in patients with CC compared with heartburn (HB).MethodsA retrospective review of 32 patients with CC (mean age 57 [95% CI: 52–62] years) and 32 patients with symptoms of HB (55 [52–62] years) referred for HRIM and MII/pH between September 2012 and September 2013 was undertaken.Key ResultsWeak peristalsis with large breaks (WPLBs) was observed in 34% of CC patients compared with only 12% of HB patients (p = 0.027). Pathological acid exposure time (AET) was identified in 81% of CC patients with WPLBs compared with 29% without (p = 0.011). Increased AET was associated with prolonged clearance time of refluxed events (p = 0.006) rather than increased number of events. AET correlated with the percentage of peristaltic events with large breaks in CC (ρ = 0.467, p = 0.007). Similar data were obtained for total bolus (acid and non‐acid) exposure time. Only one of the CC patients with WPLBs exhibited complete bolus transit (CBT) on swallowing compared with 81% without WPLBs (p < 0.001). Moreover, the percentage of peristaltic events associated with CBT negatively correlated with the percentage of peristaltic events with large breaks (r = −0.653, p < 0.001) in CC.Conclusions & InferencesOne‐third of CC patients exhibit WPLBs, which directly impacts on clearance of refluxed events and bolus's swallowed. These observations may have important implications for esophageal‐bronchial interaction in CC.