Excess risk of renal allograft loss associated with cigarette smoking.

Abstract

Cigarette smoking contributes to a number of health-related problems, but its impact on renal transplant survival beyond accelerated patient death is unclear. We performed a cohort study of 645 adult renal allograft recipients from 1985 to 1995 to evaluate the relationship between smoking and graft outcome. Twenty-four percent of recipients (156/645) were smokers at the time of transplant evaluation. Of these, 90% continued to smoke after transplantation. Pretransplant smoking was significantly associated with reduced overall graft and death-censored graft survival. Patients who were smokers at the time of pretransplant evaluation had kidney graft survival of 84%, 65%, and 48% at 1, 5, and 10 years, respectively, compared with graft survival in nonsmokers of 88%, 78%, and 62% (P=0.007). Pretransplant smoking adversely affected death-censored graft survival in recipients of cadaveric (P=0.02) and of living donor kidneys (P=0.02). Reduced graft survival in pretransplant smokers could not be accounted for by differences in rejection (64% vs. 61%, P=0.35). In a multivariate analysis, pretransplant smoking was associated with a relative risk of 2.3 for graft loss. Among patients with a smoking history before transplantation, death-censored graft survival was significantly higher for those who quit smoking before transplant evaluation. Cigarette smoking before kidney transplantation contributes significantly to allograft loss. The effect of smoking on graft outcome is not explained by increases in rejection or patient death. Smoking cessation before renal transplantation has beneficial effects on graft survival. These effects should be emphasized to patients with end-stage renal disease who are considering renal transplantation.