Short-term and Long-term Survival of Kidney Allograft: Cure Model Analysis

Abstract

Introduction. Kidney allograft failure is a major concern in kidney transplant recipients. We separately assessed risk factors for long-term and short-term survival of death-censored kidney allograft.

Materials and Methods. This study included 397 kidney recipients who underwent surgery in Afzalipour Hospital, Kerman, Iran, from 2004 to 2010. The Cox mixture cure model was used to fit independent variables for prediction of graft survival in short-term and long-term.

Results. Allograft failure occurred in 43 kidney transplant recipients (10.8%). Among the long-term survivors, hypertension (odds ratio, 3.35; 95% confidence interval [CI], 1.6 to 6.7), a serum creatinine level greater than 1.6 at hospital discharge (odds ratio, 15.1; 95% CI, 7.2 to 31.9), and donor age (odds ratio, 1.14; 95% CI, 1.09 to 1.18) were significant predictors of allograft failure. Overweight, obesity, and male donor were associated with better survival. In short-term survivors, a high body mass index (hazard ratio, 3.59; 95% CI, 1.2 to 10.7) and longer duration of pretransplant dialysis (hazard ratio, 2.4; 95% CI, 1.07 to 5.7) were associated with graft failure, while the risk of allograft failure decreased in recipients who received kidney transplants from living donors versus deceased donors (hazard ratio, 0.3; 95% CI: 0.11 to 0.78) and with each 1-year increase in donor age (hazard ratio, 0.91; 95% CI, 0.86 to 0.96).

Conclusions. Many efforts have been made to improve short-term survival of kidney allograft. The cure analysis extends the knowledge by showing that control of which variables can improve both long-term and short-term survival rates.