Renal transplantation in older recipients – results of the DZIF transplant cohort

Background Kidney transplantation in older adults is expanding, but detailed data on infection burden, antibiotic resistance, and sex-specific outcomes remain limited. The aim of the present study was to characterize infection dynamics and determinants of adverse events in recipients aged ≥ 65 years. Methods In this multicenter cohort study, 355 kidney transplant recipients aged 65–80 years (67.6% male) were followed for a median of 3.8 years. Cumulative incidences of infection, graft loss, and death were determined. Independent risk factors were identified using Cox regression analyses. Results Delayed graft function occurred in 23.9%, S-creatinine was 1.72 IQR (1.40–2.45) and eGFR 38.7 (26.2–51.3) one year after transplantation. All-cause mortality was 3.2% at year 1 and 11.8% at year 5 after transplantation. Infectious complications were frequent, with a cumulative incidence of first infection reaching 67.6% at 1 year and 81.9% at 5 years. Bacterial infections predominated, whereas viral infections persisted throughout follow-up and fungal infections occurred mainly in the early post-transplant period. During follow-up, death with a functioning graft (DWFG) was the predominant graft-related endpoint, accounting for 35 of 48 all-cause graft loss events, with infections representing the leading attributed cause (51.4%). In multivariable analyses, prolonged initial hospital stay was consistently associated with infectious outcomes and subsequent DWFG, while delayed graft function was independently associated with increased hazard of DWFG (HR 2.54, 95% CI 1.29–5.00). In time-dependent analyses, fungal infections were independently associated with a higher subsequent hazard of DWFG (HR 2.67, 95% CI 1.23–5.77). Mortality, graft-related outcomes, and infection rates were broadly similar by sex and between recipients aged 65–69 and ≥ 70 years. Conclusions Kidney transplantation in carefully selected older recipients, including those aged ≥ 70 years, was associated with sustained patient and graft survival. Infectious complications occurred frequently and constituted the leading attributed cause of DWFG; this underscores the importance of understanding why some recipients recover from infectious stress, while others experience subsequent clinical deterioration.