title: Effect of smoking on kidney transplant outcomes: analysis of the United States Renal Data System.
abstract: BACKGROUND
  We investigated the effect of smoking on postkidney transplant outcomes in the United States Renal Data System.
  
  
  METHODS
  In a retrospective cohort of 41,705 adult Medicare primary renal transplant recipients in the United States Renal Data System database transplanted from January 1, 2000, to June 30, 2006, and followed through October 31, 2006, we assessed Medicare claims for smoking. The association between renal allograft loss and death and smoking as a time-dependent variable was assessed with Cox nonproportional hazards regression.
  
  
  RESULTS
  Of 41,705 Medicare primary adult renal transplant patients, there were 9.9% patients who had evidence of prior smoking and 4.6% patients with new claims for smoking after transplant. Incident smoking (new onset smokers) occurred at a mean of 1.29±0.88 years after transplant. In the adjusted analysis, factors associated with new smoking included male gender, history of drug or alcohol use, history of chronic obstructive pulmonary disease, and later year of transplant. Compared with never smokers, incident smoking after transplant was associated with increased risk of death-censored allograft loss (adjusted hazard ratio [AHR] 1.46 [95% confidence interval {CI}: 1.19-1.79]; P<0.001) and death (AHR 2.32 [95% CI: 1.98-2.72]; P<0.001). In a sensitivity analysis excluding patients with history of chronic obstructive pulmonary disease, similar results were obtained with increased risk of death-censored allograft loss (AHR 1.43 [95% CI: 1.16-1.76]; P=0.001) and death (AHR 2.26 [95% CI: 1.91-2.66]; P<0.001).
  
  
  CONCLUSIONS
  Incident smoking was detrimental to graft and patient survival. Transplant programs should screen those at risk during transplant follow-up and have smoking cessation programs.
authors.affiliation: Nephrology, Walter Reed Army Medical Center, Washington, DC, USA.
authors.forename: Frank P
authors.initials: FP
authors.lastname: Hurst
authors.forename: Maria
authors.initials: M
authors.lastname: Altieri
authors.forename: Purav P
authors.initials: PP
authors.lastname: Patel
authors.forename: Tarun R
authors.initials: TR
authors.lastname: Jindal
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Guy
authors.forename: Anton N
authors.initials: AN
authors.lastname: Sidawy
authors.forename: Lawrence Y
authors.initials: LY
authors.lastname: Agodoa
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Abbott
authors.forename: Rahul M
authors.initials: RM
authors.lastname: Jindal
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D005260:Female; D006085:Graft Survival; D006801:Humans; D007256:Information Systems; D016030:Kidney Transplantation / Q000009:adverse effects*; D016031:Liver Transplantation / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012907:Smoking / Q000009:adverse effects*; D014184:Transplantation, Homologous; D016896:Treatment Outcome