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

## TL;DR

Older kidney transplant recipients face higher infection risks and mortality, but age alone isn't the main predictor of poor outcomes.

## Contribution

This study identifies age-specific infection patterns and mortality risks in kidney transplant recipients using a large cohort and multivariable analysis.

## Key findings

- Older recipients had higher unadjusted rates of graft failure, mortality, and specific infections like pneumonia and UTIs.
- After adjustment, age remained independently associated with mortality but not graft loss or overall infection burden.
- Early post-transplant infection burden strongly predicted graft failure, especially in the first year.

## 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 5 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.

Age-related risk assessment post-kidney transplantation by DZIF. Older transplant recipients face undefined age-specific risks. Methods: study of 572 cases across three age groups. Hospital follow-up: five years. Results show age-related differences in infection patterns, with varying incidences and hazard ratios indicating significant risks in older age groups. Early infection burden impacts graft failure and mortality. Graphs and icons indicate statistical outcomes and patterns. Research conducted at University Hospital Heidelberg, published in Transplant International 2025.