Influence of Donor Age on Graft and Patient Outcomes in Kidney Transplantation: A Systematic Review and Meta-Analysis.

BACKGROUND

Kidney transplantation remains the optimal treatment for end-stage renal disease. With rising use of older donors to expand the organ pool, concerns have emerged about the impact of donor age on transplant outcomes.

OBJECTIVES

To systematically evaluate the influence of donor age on graft and patient survival following kidney transplantation.

METHODS

We conducted a systematic review and meta-analysis following PRISMA 2020 guidelines. Literature searches were performed in PubMed, Scopus, Embase, and Cochrane up to April 2025. Eligible studies included cohort or case-control designs reporting outcomes stratified by donor age. Outcomes assessed included death-censored graft survival, patient survival, delayed graft function, and acute rejection. Hazard ratios (HRs) were pooled using random-effects models when heterogeneity (I²) exceeded 50%.

RESULTS

Seven studies involving 19,210 transplant recipients were included. Older donor age was significantly associated with an increased risk of death-censored graft loss (HR 1.73; 95% CI: 1.34-2.24) and higher patient mortality (HR 1.42; 95% CI: 1.05-1.94), particularly in the subgroup of donors aged >60 years. Heterogeneity was moderate across studies (I² = 61% for graft loss; I² = 73% for patient survival). No significant difference was observed in acute rejection rates between older and younger donor groups (OR 0.86; 95% CI: 0.60-1.23). The analysis was limited by the small number of observational studies (n = 7), with potential residual confounding and clinical heterogeneity that may affect the generalizability of the findings.

CONCLUSIONS

Donor age, particularly over 60 years, is associated with poorer graft and recipients outcomes. Despite this, older donors can be acceptable with proper recipient selection and age-matching strategies. Further studies with standardized age thresholds and long-term follow-up are needed to guide allocation policy.