Elderly Kidney Recipients of Deceased Donors >75y Show Reduced Short and Long Term Patient and Graft Survival But 2.2 Fold Better Survival Than Their Paired Wailisted Patients Remaining On Hemodialysis.

Abstract

The purpose of this study is to compare the survival of elderly patients transplanted from deceased donors (dcd) older than 75y with that of comparable waitlisted patients remaining on HD. For validating the comparison, we paired the patients looking for identical characteristics patient by patient (age group, gender, end stage renal disease, year of HD onset, type of first vascular access, time on HD and accompanying morbidities: cardiovascular, diabetes, tumors and chronic liver and chronic respiratory diseases), using a parametric survival model and we calculated the proportional risk of death by the Cox model clustering for paired patients and robust estimation of the variance. Out of the total of the 4097 recipients (KT) of first grafts from dcd transplanted between 1997 and 2011 in six hospitals of our city, 281 KT (6.9%) received a graft >75y. Patient survival of the 281 KT was 90.7%, 73.7% and 50.9% at 1, 5 and 10 years, significantly lower than that of the 3244 KT of dcd <65y: 97.1%, 90.5% and 78.9% respectively (p=0.000) but not significantly worse than that of the 572 KT of dcd aged between 66y and 75y: 93.0%, 78.0% and 52.6% respectively (p=0.260). The graft survival of the KT of dcd >75y was also significantly lower (80.1%, 60.3% and 40.5%) than that of the KT of grafts of dcd <65y (92.2%, 81.1% and 64.2%; p=0.000) but not significantly worse than that of the KT of grafts of dcd aged between 66y and 75y (86.5%, 64.2% and 41.7%; p=o.171). We then compared the survival of the elderly recipients of grafts of dcd >75y with that of comparable waitlisted patients remaining on HD. Out of the 281 KT of grafts of dcd >75y, we were able to pair 148 of them with 282 patients that had remained on HD (132 KT had two HD pairs each and 16 KT one). Patient survival at 1, 3, 5 and 10 years was 92.8%, 87.5%, 80.8% and 53.5% for the 148 KT vs 92.8%, 72.4%, 58.8% and 27.7% for the 282 patients remaining on HD. The 148 paired KT did not show statistically better survival (p=0.122) than the 133 KT that we were not able to pair. We conclude that patients remaining on HD of similar characteristics of kidney recipients of deceased donors older than 75y have a risk of death 2.2 times increased.