# Old for young kidney transplantation: a responsible option for our patients to reduce waiting time?

## TL;DR

This study shows that transplanting older donor kidneys into younger patients can be effective and reduce waiting times without compromising survival rates.

## Contribution

The study provides new evidence on the outcomes of 'old for young' kidney transplants, including a detailed analysis of graft survival and waiting times.

## Key findings

- Graft survival rates were comparable between 'old for young' and 'very old for young' transplants.
- Living donation subgroup showed significantly better graft survival for 'old for young' transplants.
- Panel-reactive antibodies were the only significant factor affecting graft survival.

## Abstract

The Eurotransplant Senior program allocating grafts from donors ≥ 65 years to recipients aged ≥ 65 years has proven good results within the last 20 years. However, “old” grafts are also allocated to younger recipients < 65 years, and this outcome of “old for young” kidney transplantations (KT) still lacks detailed investigations.

All “old for young” KT performed at four tertiary referral centers were retrospectively compared including a recent follow-up, stratifying for “old for young” (donor ≥ 65 years to recipient < 65 years) vs. “very old for young” KT (donor ≥ 70 years to recipient < 65 years).

Overall, 99 patients were included with 56 (56.6%) “old for young” and 43 (43.4%) “very old for young” KT. The median waiting time did not differ (60.7 vs. 45.8 months, respectively) at comparable living donation rates (57.1% vs. 44.2%) as well as intra- and postoperative results. At a median follow-up of 44 months (range 1; 133), the 3-year graft survival of 91% vs. 87% did not significantly vary. In subgroup analyses assessing living donation or donation after brain death (DBD) KT only, the graft survival was significantly longer for “old for young” KT within the living donation subgroup. In multivariate Cox regression analyses, the presence of panel-reactive antibodies was the only significant impact factor on graft survival (HR 8.32, p = 0.001).

This analysis clearly demonstrates the effectiveness of the "old for young" approach, enabling favorable perioperative results as well as comparable data of graft- and overall survival, while reducing waiting time for eligible patients.

The online version contains supplementary material available at 10.1007/s00345-024-04779-8.