Patient survival after renal transplantation: II. The impact of smoking

Renal transplant recipients have significantly higher mortality than indivi duals without kidney disease and the excess mortality is mainly due to card iovascular causes. In this study, we sought to determine the impact of smok ing, a major cardiovascular risk factor, on patient and renal graft surviva l. The study population included all adult recipients of first cadaveric ki dney transplants done in our institution from 1984 to 1991. By selection, a ll patients were alive and had a functioning graft for at least 1 yr after transplantation. Smoking history was gathered prior to transplantation. The follow-up period was 84.3 +/- 41 months and during this time 28% of the pa tients died and 21% lost their graft. By univariate and multivariate analys is, patient survival, censored at the time of graft loss, correlated with t hese pre-transplant variables: age (p < 0.0001); diabetes (p = 0.0002); his tory of cigarette smoking (p = 0.004); time on dialysis prior to the transp lant (p = 0.0005); and cardiomegaly by chest X-ray (p = 0.0005). Posttransp lant variables did not correlate with patient mortality. By Cox regression, patient survival time was significantly shorter in diabetics (p < 0.0001), smokers (p = 0.0005), and recipients older than 40 yr. However, there were no significant differences between the survival of smokers, non-diabetics, diabetics, and older recipients. Patient death was the most common cause o f renal transplant failure in smokers, in patients older than 40 yr, and in diabetics, but these patient characteristics did not correlate with graft survival. The prevalence of different causes of death was not significantly different between smokers and non-smokers. In conclusion, a history of cig arette smoking correlates with decreased patient survival after transplanta tion, and the magnitude of the negative impact of smoking in renal transpla nt recipients is quantitatively similar to that of diabetes.