title: Black renal transplant recipients have poorer long-term graft survival than CYP3A5 expressers from other ethnic groups.
abstract: BACKGROUND
  African American transplant recipients have poorer long-term outcomes than Caucasian Americans. This difference was not found in French patients, suggesting socialized medicine overcame this disparity. It has also been hypothesized that the difference relates to the higher prevalence of Black individuals who express the metabolic enzyme cytochrome P4503A5 (CYP3A5), with consequent altered handling of immunosuppressive drugs.
  
  
  METHODS
  Records of 555 (50 Black; 505 non-Black) sequential renal transplant recipients from a single UK centre were analysed.
  
  
  RESULTS
  Outcomes were significantly worse for Black patients: death-censored graft survival (5-year 66% versus 87%, P = 0.001); halving of year one estimated glomerular filtration rate (mean 8.8 versus 10.8 years, P = 0.008); first-year graft loss (12% versus 3.8%, P = 0.02); and death-censored graft survival in patients surviving the first year with functioning grafts (5-year 77% versus 94%, P = 0.02). Death-censored 5-year graft survival was poorer in Black CYP3A5 expressers than in non-Black CYP3A5 expressers (62% versus 93%, P = 0.002). Following multivariate analysis, the Black group demonstrated poorer graft survival as compared to the non-Black group (hazard ratio 0.46, 95% CI 0.25-0.85, P = 0.002). In a subgroup of genotyped transplant recipients, ethnicity (hazard ratio 0.31, 95% CI 0.15-0.64, P = 0.002), and not CYP3A5 expresser status, persists as an independent risk factor for graft survival following multivariate analysis.
  
  
  CONCLUSIONS
  In this cohort of patients with socialized medicine, Black recipients had poorer long-term outcomes than individuals from other ethnic groups. This was independent of CYP3A5 expresser status.
authors.affiliation: Cellular and Molecular Medicine, Renal Medicine, St. George's, University of London, Cranmer Terrace, SW17 0RE, UK.
authors.forename: Fu Liang
authors.initials: FL
authors.lastname: Ng
authors.forename: David W
authors.initials: DW
authors.lastname: Holt
authors.forename: Rene W S
authors.initials: RW
authors.lastname: Chang
authors.forename: Iain A M
authors.initials: IA
authors.lastname: Macphee
mesh_terms: D000328:Adult; D044383:Black People; D051544:Cytochrome P-450 CYP3A / Q000096:biosynthesis*; D005260:Female; D006085:Graft Survival; D006801:Humans; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D013997:Time Factors; D001741:Black or African American
chemical_list: C510164:CYP3A5 protein, human; D051544:Cytochrome P-450 CYP3A