title: Association between proximity to the attending nephrologist and mortality among patients receiving hemodialysis.
abstract: BACKGROUND
  Many Canadian patients who receive hemodialysis live far from their attending nephrologist, which may affect clinical outcomes. We investigated whether patients receiving hemodialysis who live farther from their attending nephrologist are more likely to die than those who live closer.
  
  
  METHODS
  We studied a random sample of 18,722 patients who began hemodialysis between 1990 and 2000 in Canada. We calculated the distance between each patient's residence location at the start of dialysis and the practice location of their attending nephrologist. We used Cox proportional hazards models to examine the adjusted relation between distance and clinical outcomes (death from all causes, infectious causes and cardiovascular causes) over a follow-up period of up to 14 years.
  
  
  RESULTS
  During the follow-up period (median 2.5 yr, interquartile range 1.0-4.7 yr), 11,582 (62%) patients died. Compared with patients who lived within 50 km of their nephrologist, the adjusted hazard ratio of death among those who lived 50.1-150 km away was 1.06 (95% confidence interval [CI] 1.01-1.12), 1.13 (95% CI 1.04-1.22) for those who lived 150.1-300 km away and 1.13 (95% CI 1.03-1.24) for those who lived more than 300 km from their nephrologist (p for trend < 0.001). The risk of death from infectious causes increased with greater distance from the attending nephrologist (p for trend < 0.001). The risk of death from cardiovascular causes did not increase with distance from the attending nephrologist (p for trend = 0.21). Compared with patients who lived within 50 km of their nephrologist, the adjusted hazard ratio of death among those who lived more than 300 km away was 1.75 (95% CI 1.32-2.32) for infectious causes and 0.93 (95% CI 0.79-1.09) for cardiovascular causes.
  
  
  CONCLUSIONS
  Mortality associated with hemodialysis was greater among patients who lived farther from their attending nephrologist, as compared with those who lived closer. This was especially evident for death from infectious causes.
authors.affiliation: Division of Nephrology and Transplant Immunology, Department of Medicine, University of Alberta, Edmonton, Alta. mtonelli-admin@med.ualberta.ca
authors.forename: Marcello
authors.initials: M
authors.lastname: Tonelli
authors.forename: Braden
authors.initials: B
authors.lastname: Manns
authors.forename: Bruce
authors.initials: B
authors.lastname: Culleton
authors.forename: Scott
authors.initials: S
authors.lastname: Klarenbach
authors.forename: Brenda
authors.initials: B
authors.lastname: Hemmelgarn
authors.forename: Natasha
authors.initials: N
authors.lastname: Wiebe
authors.forename: John S
authors.initials: JS
authors.lastname: Gill
mesh_terms: D000368:Aged; D002170:Canada / Q000453:epidemiology; D005260:Female; D006297:Health Services Accessibility; D006801:Humans; D008297:Male; D008875:Middle Aged; D011365:Professional Practice Location; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012042:Registries; D006435:Renal Dialysis / Q000401:mortality*; D051437:Renal Insufficiency / Q000453:epidemiology / Q000628:therapy*; D012307:Risk Factors; D015996:Survival Rate; D014195:Travel