10 Conclusions

Based on the findings of this analysis and results reported by other authors it can be concluded that the objectives of the ESP have been met and the program is beneficial for kidney transplantation candidates, in particular for elderly ones, but in general also for the entire group of waiting list patients. The main reasons are:

1. The program led to an increased availability of elderly donors from 169 (10% of all donors) in 1998 to 239 (almost 15% of all donors) in 2004.
2. The waiting time for elderly recipients transplanted within the ESP was decreased by 5 months over the course of the analysis, while the waiting time via ETKAS in Control 1 increased by 2,4 months and for Control 2 by one year over the same period of time. As a result, the ESP group is currently the group with the shortest waiting time.
3. The cold ischemia time for ESP patients was significantly shortened with a mean of approximately 12 hours compared with over 17 hours in both control groups. This translated into a significantly higher percentage of initial function, a reduced rate of DGF and lower SCr values at all timepoints in the ESP group compared to Control 1. Maintaining short ischemia times or even reducing them further seems to be important in order to minimize the incidence of DGF that was shown to be a strong independent risk factor for patient survival, censored and uncensored graft survival as well as acute rejection.
4. The main clinical outcomes in recipients of organs from donors age 65 or older were not negatively impacted by the ESP allocation. Donor age is the main variable driving differences in survival between ESP and Control2. Old donor kidneys did not survive longer in a younger recipient.

From the analysis of risk factors and clinical outcomes performed in this investigation, certain recommendations to improve the program can be given. In particular, using HLA matching should be considered instead of waiting time as an allocation criterion. In fact, results point to an effective immune response even in old recipients (more rejections despite adequate therapy) and at the same time a high incidence of infection-related complications, limiting the room for increased immunosuppression. The identification of specific immunosuppressive treatments for elderly patients and a comparison of clinical outcomes of transplanted and non-transplanted elderly patients are among the most relevant topics future research could address.