Impact of kidney transplant morbidity on elderly recipients' outcomes

Abstract
Background and aims Nowadays, advanced age does not represent an absolute contraindication to kidney transplantation (KT). However, aging is frequently associated with multiple comorbidities and lower performance status, making KT candidates less surgically fit. Limited data are available on the impact of KT morbidity on elderly recipients' outcomes. Methods Retrospective study on a single center cohort of 130 KT recipients over 65 years old, representing 16.2% of KT clinical series, during the period 2000-2018. Number and severity of comorbidities were evaluated with the Charlson Comorbidity index (CCI). Results The median age at transplantation was 67 [IQR66-71] years and median CCI was 5 [IQR4-6]. The prevalence of postoperative complications with a Clavien-Dindo (C-D) severity score > 2 was 29%. Increasing age did not predict KT morbidity in terms of C-D score > 2, infectious, respiratory, cardiologic, urologic or vascular complications, delayed graft function, symptomatic lymphocele, bleeding, acute or chronic rejection. Conversely, CCI score was a predictor of overall complications with C-D score > 2, cardiologic, respiratory and vascular complications, and bleeding. Among others, CCI score, post-KT cardiologic complications, C-D score > 2 were identified as significant predictors of both early mortality and graft loss in univariate analysis. Increasing recipient age did not correlate with graft loss risk and graft loss did not impact patient survival. C-D score > 2 was a predictor of poor survival even in multivariate analysis. Conclusions Elderly recipients showed a significant vulnerability to KT morbidity which correlates with CCI. While graft loss did not impact recipient survival, severe postoperative complications (C-D > 2) were independently associated increased mortality.