Frailty assessed using the Edmonton Frail Scale predicts mortality and waitlist removal for kidney transplant candidates: a prospective study

Frailty is associated with adverse outcomes in kidney transplant (KT) candidates. The Edmonton Frail Scale (EFS) is a reliable tool to access frailty in a multidimensional approach. However, its prognostic association with outcomes in transplant waitlist remains unclear. Hence this study evaluated the association between frailty and the outcome of death or permanent delist in KT candidates as well as its relationship with comorbidities and quality of life (QOL). In a prospective observational cohort study of 279 adults KT candidates, frailty was assessed using the EFS, QOL with the EuroQol 5D-3L, and the comorbidity was evaluated using the Charlson comorbidity index (CCI). Competing risk models, multivariable and causal mediation analyses were used. Participants were classified as robust (27%), vulnerable (31%), or frail (42%). Frail participants were older, less educated, had a longer time on dialysis, higher CCI, and lower QOL ( p < 0.05). Age, female, and higher CCI were independently associated with frailty severity. After 22.8 months of follow-up, 14% of participants died or were delisted, and 17% underwent a KT. The cumulative incidence of the outcome was higher in frail individuals (25.6% vs. 8.1%, p < 0.001). Higher EFS scores, time on dialysis, and CCI were associated with this outcome. CCI partially mediated this association, and a direct effect of frailty persisted. Frailty is highly prevalent among KT candidates and is associated with high comorbidity burden, low QOL, and increased risk of adverse outcomes.