title: Ratio between proximal/distal gastroesophageal reflux does not discriminate abnormal proximal reflux.
abstract: BACKGROUND
  The threshold for pathologic proximal acid reflux is a controversial topic. Most values previously published are based on absolute numbers. We hypothesized that a relative value representing the quantitative relation between the amount of acid reflux that reaches proximal levels and the amount of distal reflux would be a more adequate parameter for defining pathologic proximal reflux.
  
  
  METHODS
  We studied 20 healthy volunteers (median age 30 years, 70 % women) without gastroesophageal reflux disease (GERD); 50 patients (median age 51 years, 60 % women) with esophageal symptoms of GERD (heartburn, regurgitation); and 50 patients (median age 49 years, 60 % women) with extra-esophageal symptoms of GERD. All individuals underwent manometry and dual-probe pH monitoring. GERD was defined as a DeMeester score >14.7. The proximal/distal reflux ratio was calculated for all six parameters that constitute the DeMeester score.
  
  
  RESULTS
  Absolute numbers for proximal reflux were not different for the three groups except for the number of episodes of reflux, which was higher for patients with GERD and esophageal symptoms than for patients with GERD and extra-esophageal symptoms (p = 0.007). The number of episodes of distal reflux reaching proximal levels was significantly higher in volunteers than in all patients with GERD and significantly higher in patients with GERD and esophageal symptoms than in those with extra-esophageal symptoms.
  
  
  CONCLUSIONS
  Our results suggest that the proximal/distal reflux ratio is not a good normative value for defining proximal reflux.
authors.affiliation: Department of Surgery, Escola Paulista de Medicina, Federal University of Sao Paulo, Rua Diogo de Faria 1087 cj 301, São Paulo, SP, 04037-003, Brazil.
authors.forename: Sebastião Carlos Pannocchia
authors.initials: SC
authors.lastname: Neto
authors.forename: Fernando A M
authors.initials: FA
authors.lastname: Herbella
authors.forename: Luciana C
authors.initials: LC
authors.lastname: Silva
authors.forename: Marco G
authors.initials: MG
authors.lastname: Patti
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D050782:Esophageal pH Monitoring; D005260:Female; D005764:Gastroesophageal Reflux / Q000175:diagnosis* / Q000503:physiopathology; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged