Backgrounds: With the growing shortage of organ donors combined with the increasing demand for organs, more expanded criteria donors are being used. The age of donors and recipients is increasing, and recipients are very concerned about the age of the donor when they are matched. However, utilizing older donors among recipients is a way to similarly increase the donor pool for kidney transplants, Thus,  we investigated the impact of donor-recipient age difference on graft outcomes after renal transplantation in our center.
Methods: Between April 1978  and June 2023, we assessed 854 renal  transplantation patients. Based on recipient-donor age difference histogram, we stratified these patients into 5 groups: Group 1(15< Δage<50, n=175), Group 2(5< Δage<15, n=165) , Group 3(-5 <Δage<5, n=223), Group 4(-20< Δage<-5, n=156), and group 5 (-50< Δage<-20, n=135). Hazard ratios were analyzed to ascertain graft outcomes.
Results: There were no significant differences in clinical outcomes between 5 groups except eGFR at 12months after renal transplantation.Graft survival rate at 10 years after kidney transplantation was significantly different among the 5 subgroups (P = .015); the graft survival rate at 10 years was 94.8% in group 1; 91.8% in group 2, 93.5% in group 3, 92.5% in group 4; and 82.4% in group 5, respectively.In Cox proportional hazard models,, the recipient donor age difference <- 20 group showed a higher risk for graft failure than other group (HR 2.072, 95% CI 1.313-3.269).

Conclusion: Using older donors does not seem to have an impact on long-term survival, except when donors are used who are more than 20 years older than the recipient. This consolidates the concept that the use of elderly donors does not affect survival, allowing the pool of donors to be expanded.