title: Association of distance from a transplant center with access to waitlist placement, receipt of liver transplantation, and survival among US veterans.
abstract: OBJECTIVE
  Centralization of specialized health care services such as organ transplantation and bariatric surgery is advocated to improve quality, increase efficiency, and reduce cost. The effect of increased travel on access and outcomes from these services is not fully understood.
  
  
  OBJECTIVE
  To evaluate the association between distance from a Veterans Affairs (VA) transplant center (VATC) and access to being waitlisted for liver transplantation, actually having a liver transplant, and mortality.
  
  
  METHODS
  Retrospective study of veterans meeting liver transplantation eligibility criteria from January 1, 2003, until December 31, 2010, using data from the Veterans Health Administration's integrated, national, electronic medical record linked to Organ Procurement and Transplantation Network data.
  
  
  METHODS
  The primary outcome was being waitlisted for transplantation at a VATC. Secondary outcomes included being waitlisted at any transplant center, undergoing a transplantation, and survival.
  
  
  RESULTS
  From 2003-2010, 50,637 veterans were classified as potentially eligible for transplant; 2895 (6%) were waitlisted and 1418 of those were waitlisted (49%) at 1 of the 5 VATCs. Of 3417 veterans receiving care at a VA hospital located within 100 miles from a VATC, 244 (7.1%) were waitlisted at a VATC and 372 (10.9%) at any transplant center (VATC and non-VATCs). Of 47,219 veterans receiving care at a VA hospital located more than 100 miles from a VATC, 1174 (2.5%) were waitlisted at a VATC and 2523 (5.3%) at any transplant center (VATC and non-VATCs). In multivariable models, increasing distance to closest VATC was associated with significantly lower odds of being waitlisted at a VATC (odds ratio [OR], 0.91 [95% CI, 0.89-0.93] for each doubling in distance) or any transplant center (OR, 0.94 [95% CI, 0.92-0.96] for each doubling in distance). For example, a veteran living 25 miles from a VATC would have a 7.4% (95% CI, 6.6%-8.1%) adjusted probability of being waitlisted, whereas a veteran 100 miles from a VATC would have a 6.2% (95% CI, 5.7%-6.6%) adjusted probability. In adjusted models, increasing distance from a VATC was associated with significantly lower transplantation rates (subhazard ratio, 0.97; 95% CI, 0.95-0.98 for each doubling in distance). There was significantly increased mortality among waitlisted veterans from the time of first hepatic decompensation event in multivariable survival models (hazard ratio, 1.03; 95% CI, 1.01-1.04 for each doubling in distance). For example, a waitlisted veteran living 25 miles from a VATC would have a 62.9% (95% CI, 59.1%-66.1%) 5-year adjusted probability of survival from first hepatic decompensation event compared with a 59.8% (95% CI, 56.3%-63.1%) 5-year adjusted probability of survival for a veteran living 100 miles from a VATC.
  
  
  CONCLUSIONS
  Among VA patients meeting eligibility criteria for liver transplantation, greater distance from a VATC or any transplant center was associated with lower likelihood of being waitlisted, receiving a liver transplant, and greater likelihood of death. The relationship between these findings and centralizing specialized care deserves further investigation.
authors.affiliation: Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia2Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia3Leonard Davis Institute of Healt.
authors.forename: David S
authors.initials: DS
authors.lastname: Goldberg
authors.affiliation: Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia3Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia.
authors.forename: Benjamin
authors.initials: B
authors.lastname: French
authors.affiliation: Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia2Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia.
authors.forename: Kimberly A
authors.initials: KA
authors.lastname: Forde
authors.affiliation: Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia4Division of General Internal Medicine, University of Pennsylvania, Philadelphia5Center for Health Equity Research and Promotion, Philadelphia VA Medical Center, Philadel.
authors.forename: Peter W
authors.initials: PW
authors.lastname: Groeneveld
authors.affiliation: Department of Medicine, University of Pennsylvania, Philadelphia.
authors.forename: Therese
authors.initials: T
authors.lastname: Bittermann
authors.affiliation: Department of Veterans Affairs/Office of Public Health, Philadelphia, Pennsylvania.
authors.forename: Lisa
authors.initials: L
authors.lastname: Backus
authors.affiliation: Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia3Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia8Division of Pulmonary, Allergy, and Criti.
authors.forename: Scott D
authors.initials: SD
authors.lastname: Halpern
authors.affiliation: Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia9Gastroenterology Section, Philadelphia VA Medical Center, Philadelphia, Pennsylvania.
authors.forename: David E
authors.initials: DE
authors.lastname: Kaplan
mesh_terms: D003695:Delivery of Health Care / Q000639:trends; D005260:Female; D006297:Health Services Accessibility / Q000706:statistics & numerical data*; D006801:Humans; D016031:Liver Transplantation / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012306:Risk; D016019:Survival Analysis; D014195:Travel; D014481:United States / Q000453:epidemiology; D014728:Veterans / Q000706:statistics & numerical data*; D014850:Waiting Lists