Supplementary Material for: Renal transplantation in the elderly. Are they all the same? A multicenter, comorbidity based study

Introduction: The age for kidney transplantation (KT) is no longer a limitation and several studies have shown benefits in the survival of elderly patients. The aim of this study was to examine the relationship of the baseline Charlson comorbidity index (CCI) score to morbidity and mortality after transplantation. Methods: In this multicentric observational retrospective cohort study, we included patients older than 60 years admitted on the waiting list (WL) for deceased donor KT from 01/01/2006 until 31/12/2016. The CCI score was calculated for each patient at inclusion on the WL. Results: Data for analysis was available of 387 patients. The patients were divided in tertiles of CCI: group 1(CCI:1-2) n=117, group 2 (CCI: 3-4) n=158 and group 3(CCI: ≥5) n=112. Patient survival was significantly different between CCI groups at 1, 3 and 5 years respectively: 90%, 88% and 84% for group 1, 88%, 80% and 72% for group 2, and 87%, 75% and 63% for group 3 (p< 0.0001). Variables associated with mortality were: CCI score (p<0.0001), HLA mismatch (p=0.014), length of hospital stay (p<0.0001), surgical complications (p=0.048). Conclusion: Individualized strategies to modify these variables may improve patient´s morbidity and mortality after KT.