title: Increased proximal acid reflux is associated with early readmission following lung transplantation.
abstract: BACKGROUND
  Gastroesophageal reflux disease has been associated with poor outcomes following lung transplantation. However, the association between pretransplant reflux and post-transplant readmission, an indicator of early clinical outcome, has not been previously assessed.
  
  
  METHODS
  This was a retrospective cohort study of lung transplant recipients undergoing pretransplant multichannel intraluminal impedance and pH (MII-pH) study off acid suppression at a tertiary care center since 2007. Subjects with pretransplant fundoplication were excluded. Time to readmission was defined as duration from post-transplant discharge to next hospital admission for any reason. Subgroup analysis was performed to exclude elective readmissions. Time-to-event analysis was performed using Cox proportional hazards model, with appropriate censoring.
  
  
  RESULTS
  Forty-three subjects (60% men, mean age: 57, median follow-up: 1.7 years) met inclusion criteria for the study. Patient demographics and pretransplant cardiopulmonary function were similar between readmission cohorts. Time to all-cause readmission was associated with increased distal acid episodes (HR: 3.15, p = 0.04) and proximal acid episodes (HR: 3.61, p = 0.008) on impedance, increased acid exposure on pH (HR: 2.22, p = 0.04), and elevated Demeester score (HR: 2.26, p = 0.03). When elective readmissions were excluded, early readmission remained significantly associated with increased proximal acid reflux episodes (HR: 2.49, p = 0.04). All findings were confirmed on Kaplan-Meier analysis.
  
  
  CONCLUSIONS
  Elevated proximal acid reflux on pretransplant MII-pH testing was associated with early readmission following lung transplantation, even after excluding elective readmissions. Exposure to severe acid reflux has measurable effects on early postoperative outcomes such as readmission, and aggressive early antireflux therapy should be considered.
authors.affiliation: Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women's Hospital, Boston, MA, USA.|Department of Gastroenterology, VA Boston Healthcare System, Boston, MA, USA.|Harvard Medical School, Boston, MA, USA.
authors.forename: W-K
authors.initials: WK
authors.lastname: Lo
authors.affiliation: Harvard Medical School, Boston, MA, USA.|Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: H J
authors.initials: HJ
authors.lastname: Goldberg
authors.affiliation: Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women's Hospital, Boston, MA, USA.|Harvard Medical School, Boston, MA, USA.
authors.forename: R
authors.initials: R
authors.lastname: Burakoff
authors.affiliation: Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: N
authors.initials: N
authors.lastname: Feldman
authors.affiliation: Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women's Hospital, Boston, MA, USA.|Harvard Medical School, Boston, MA, USA.
authors.forename: W W
authors.initials: WW
authors.lastname: Chan
mesh_terms: D000328:Adult; D015331:Cohort Studies; D017097:Electric Impedance; D050782:Esophageal pH Monitoring; D005260:Female; D005764:Gastroesophageal Reflux / Q000150:complications*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D053208:Kaplan-Meier Estimate; D016040:Lung Transplantation / Q000401:mortality; D008297:Male; D008875:Middle Aged; D010359:Patient Readmission / Q000706:statistics & numerical data*; D016016:Proportional Hazards Models; D012189:Retrospective Studies
keywords: GERD; acid reflux; impedance; lung transplant; post-transplant; readmission