title: Differences in progression to ESRD between black and white patients receiving predialysis care in a universal health care system.
abstract: OBJECTIVE
  Studies performed in the United States showed that blacks progress from CKD to ESRD faster than do whites. Possible explanations are differences in health care system factors. This study investigated whether progression is also faster in a universal health care system, where all patients receive comparable care.
  
  
  METHODS
  Data from the PREdialysis PAtient REcord study, a multicenter follow-up study of patients with CKD who started predialysis care in The Netherlands (1999-2011), were analyzed. Time-dependent Cox proportional hazards models were used to estimate the hazard ratio (HR) for starting renal replacement therapy (RRT), and linear mixed models were used to compare renal function decline (RFD) between blacks and whites. To explore possible mechanisms, analyses were adjusted for patient characteristics.
  
  
  RESULTS
  At initiation of predialysis care, blacks (n=49) were younger and had more diabetes mellitus, higher proteinuria levels, and a higher estimated GFR than whites (n=946). Median follow-up time in months was similar (blacks: 13.9 [boundaries of interquartile range (IQR), 5.3 to 19.5]; whites: 13.1 [IQR, 5.1 to 24.0]). For blacks compared with whites, the crude HR for starting RRT within the first 15 months was 0.86 (95% confidence interval [CI], 0.55 to 1.34) and from 15 months onward, 1.93 (95% CI, 1.02 to 3.68), which increased after adjustment. RFD was faster by 0.18 (95% CI, 0.05 to 0.32) ml/min per 1.73 m(2) per month in blacks compared with whites.
  
  
  CONCLUSIONS
  Blacks receiving predialysis care in a universal health care system have faster disease progression than whites, suggesting that health care system factors have a less influential role than had been thought in explaining black-white differences.
authors.affiliation: Department of Clinical Epidemiology, Leiden University Medical Center, The Netherlands.
authors.forename: Tessa O
authors.initials: TO
authors.lastname: van den Beukel
authors.forename: Moniek C M
authors.initials: MC
authors.lastname: de Goeij
authors.forename: Friedo W
authors.initials: FW
authors.lastname: Dekker
authors.forename: Carl E H
authors.initials: CE
authors.lastname: Siegert
authors.forename: Nynke
authors.initials: N
authors.lastname: Halbesma
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D044383:Black People / Q000706:statistics & numerical data*; D003920:Diabetes Mellitus / Q000208:ethnology; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D054624:Health Status Disparities; D006801:Humans; D007676:Kidney Failure, Chronic / Q000208:ethnology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D051436:Renal Insufficiency, Chronic / Q000208:ethnology* / Q000503:physiopathology / Q000628:therapy*; D017582:Renal Replacement Therapy / Q000706:statistics & numerical data; D019472:Universal Health Insurance; D044465:White People / Q000706:statistics & numerical data*