Age-Related Risk After Kidney Transplantation: A Comprehensive Analysis of Infection Burden, Graft Outcomes, and Mortality

Abstract

Given the increasing number of kidney transplantation in elderly recipients, understanding age-specific risks is essential for optimized post-transplant care. We analyzed 572 kidney transplant recipients from the DZIF Transplant Cohort (2012–2023), stratified by age: <40 (n=146), 40–60 (n=279), >60 years (n=147). Outcomes included infection burden, graft outcomes, and mortality over a median follow-up of five years. Multivariable Cox models with inverse probability weighting, adjusted for clinical confounders, was applied. In older recipients, the unadjusted 5-year rates of graft failure, mortality, and infections were significantly higher— both overall and for specific types, including pneumonia, urinary tract infections, invasive opportunistic infections, and multidrug-resistant infections. After adjustment, age remained only independently associated with mortality (HR=6.21, p=0.02), but not with overall infection burden or graft loss. Older patients exhibited a shift in pathogen prevalence, particularly for Pseudomonas aeruginosa and more severe herpesvirus infections, as well as higher infection-related morbidity, which contributed to graft failure. The first post-transplant year was critical, with infection burden strongly predicting graft failure (HR 1.16, p<0.01). Age alone generally does not predict adverse transplant outcomes. Post-transplant care in elderly recipients should focus on early infection control with pathogen-targeted surveillance.