title: Reflux pattern and role of impedance-pH variables in predicting PPI response in patients with suspected GERD-related chronic cough.
abstract: BACKGROUND
  Gastro-oesophageal reflux disease (GERD) may contribute to the onset of chronic cough (CC); however, the multichannel intraluminal impedance-pH (MII-pH) monitoring is often within the normal range and the response to proton pump inhibitors (PPIs) unsatisfactory. The measure of impedance baseline (IB) increases the sensitivity of MII-pH in patients with typical symptoms.
  
  
  OBJECTIVE
  To evaluate the role of MII-pH variables, including IB, in predicting PPI response and to define the characteristics of the reflux pattern in CC patients.
  
  
  METHODS
  Prospectively selected CC patients suspected GERD-related underwent MII-pH monitoring and, therefore, received a double dose of PPIs for at least 6 weeks. Patients filled symptom scores before MII-pH and after PPI therapy. MII-pH data were compared with those obtained in 60 non-erosive reflux disease patients with typical symptoms.
  
  
  RESULTS
  A total of 156 CC patients entered the study: 68 (43.5%) responders and 88 (56.5%) nonresponders to PPIs. The number of reflux episodes was significantly higher in CC compared with that in typical symptoms patients. Nonresponder CC patients with a pathological acid exposure time (AET) and/or IB value were 43/88 (49%), while 15/88 (17%) presented only pathological AET (P < 0.001). CC patients with a pathological AET or IB, or with both a pathological AET and IB, showed a probability of PPI response twofold greater than patients with normal AET and IB.
  
  
  CONCLUSIONS
  The presence of a pathological AET or pathological IB in CC patients is associated with a greater probability of PPI response. IB is a promising variable in patients with CC, as it increases the diagnostic yield of MII-pH and allows confirmation of the GERD diagnosis in these patients.
authors.affiliation: Unit of Digestive Disease, Campus Bio Medico University, Rome, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Ribolsi
authors.forename: E
authors.initials: E
authors.lastname: Savarino
authors.forename: N
authors.initials: N
authors.lastname: De Bortoli
authors.forename: P
authors.initials: P
authors.lastname: Balestrieri
authors.forename: M
authors.initials: M
authors.lastname: Furnari
authors.forename: I
authors.initials: I
authors.lastname: Martinucci
authors.forename: M
authors.initials: M
authors.lastname: Casale
authors.forename: F
authors.initials: F
authors.lastname: Greco
authors.forename: F
authors.initials: F
authors.lastname: Salvinelli
authors.forename: V
authors.initials: V
authors.lastname: Savarino
authors.forename: S
authors.initials: S
authors.lastname: Marchi
authors.forename: M
authors.initials: M
authors.lastname: Cicala
mesh_terms: D000328:Adult; D000368:Aged; D002908:Chronic Disease; D003371:Cough / Q000175:diagnosis* / Q000188:drug therapy / Q000209:etiology; D017097:Electric Impedance; D050782:Esophageal pH Monitoring; D005260:Female; D005764:Gastroesophageal Reflux / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008875:Middle Aged; D054328:Proton Pump Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D055815:Young Adult
chemical_list: D054328:Proton Pump Inhibitors