title: Abilities of Oropharyngeal pH Tests and Salivary Pepsin Analysis to Discriminate Between Asymptomatic Volunteers and Subjects With Symptoms of Laryngeal Irritation.
abstract: OBJECTIVE
  It has been a challenge to confirm the association between laryngeal symptoms and physiological reflux disease. We examined the ability of oropharyngeal pH tests (with the Restech Dx-pH system) and salivary pepsin tests (with Peptest) to discriminate between asymptomatic volunteers (controls) and subjects with a combination of laryngeal and reflux symptoms (laryngeal ± reflux).
  
  
  METHODS
  We performed a physician-blinded prospective cohort study of 59 subjects at a single academic institution. Adult volunteers were recruited and separated into 3 groups on the basis of GerdQ and Reflux Symptom Index scores: controls (n = 20), laryngeal symptoms (n = 20), or laryngeal + reflux symptoms (n = 19). Subjects underwent laryngoscopy and oropharyngeal pH tests and submitted saliva samples for analysis of pepsin concentration. Primary outcomes included abnormal acid exposure and composite (RYAN) score for oropharyngeal pH tests and abnormal mean salivary pepsin concentration that was based on normative data.
  
  
  RESULTS
  Complete oropharyngeal pH data were available from 53 subjects and complete salivary pepsin data from 35 subjects. We did not observe any significant differences between groups in percent of time spent below pH 4.0, 5.0, 5.5, 6.0, or RYAN scores or percent of subjects with positive results from tests for salivary pepsin (53% vs 40% vs 75%; P = .50, respectively). The laryngeal + reflux group had a significantly higher estimated mean concentration of salivary pepsin (117.9 ± 147.4 ng/mL) than the control group (32.4 ± 41.9 ng/mL) or laryngeal symptom group (7.5 ± 11.2 ng/mL) (P = .01 and P = .04, respectively).
  
  
  CONCLUSIONS
  By using current normative thresholds, oropharyngeal pH testing and salivary pepsin analysis are not able to distinguish between healthy volunteers and subjects with a combination of laryngeal and reflux symptoms.
authors.affiliation: Division of Gastroenterology and Hepatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois. Electronic address: rena.yadlapati@northwestern.edu.
authors.forename: Rena
authors.initials: R
authors.lastname: Yadlapati
authors.affiliation: Division of Gastroenterology and Hepatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
authors.forename: Christopher
authors.initials: C
authors.lastname: Adkins
authors.affiliation: Division of Gastroenterology and Hepatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
authors.forename: Diana-Marie
authors.initials: DM
authors.lastname: Jaiyeola
authors.affiliation: University of Rochester School of Medicine and Dentistry, University of Rochester Medical Center, Rochester, New York.
authors.forename: Alcina K
authors.initials: AK
authors.lastname: Lidder
authors.affiliation: Division of Gastroenterology, University of Utah, Salt Lake City, Utah.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Gawron
authors.affiliation: Division of Otolaryngology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
authors.forename: Bruce K
authors.initials: BK
authors.lastname: Tan
authors.affiliation: University of Indiana School of Medicine, Indianapolis, Indiana.
authors.forename: Nadine
authors.initials: N
authors.lastname: Shabeeb
authors.affiliation: Division of Otolaryngology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
authors.forename: Caroline P E
authors.initials: CP
authors.lastname: Price
authors.affiliation: Division of Otolaryngology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
authors.forename: Neelima
authors.initials: N
authors.lastname: Agrawal
authors.affiliation: Division of Gastroenterology and Hepatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
authors.forename: Michael
authors.initials: M
authors.lastname: Ellenbogen
authors.affiliation: Division of Otolaryngology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
authors.forename: Stephanie S
authors.initials: SS
authors.lastname: Smith
authors.affiliation: Division of Otolaryngology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
authors.forename: Michiel
authors.initials: M
authors.lastname: Bove
authors.affiliation: Division of Gastroenterology and Hepatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
authors.forename: John E
authors.initials: JE
authors.lastname: Pandolfino
mesh_terms: D000328:Adult; D003955:Diagnostic Tests, Routine / Q000379:methods*; D005260:Female; D005764:Gastroesophageal Reflux / Q000175:diagnosis*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007828:Laryngoscopy; D008297:Male; D008875:Middle Aged; D009960:Oropharynx / Q000737:chemistry*; D010434:Pepsin A / Q000032:analysis*; D010865:Pilot Projects; D011446:Prospective Studies; D012463:Saliva / Q000737:chemistry*; D014838:Volunteers
chemical_list: D010434:Pepsin A
keywords: Extraesophageal Reflux; Gastroesophageal Reflux; Oropharyngeal pH Testing; Salivary Pepsin Analysis