Impact of frailty on mortality and transfer to hemodialysis after peritoneal dialysis initiation.

Background: Frailty is associated with poor outcomes for patients on dialysis; however, dedicated studies among incident peritoneal dialysis (PD) patients are lacking. This study aims to determine the association between frailty and mortality/transfer to hemodialysis (HD) among incident PD patients and identify whether dialysis modality (PD vs. HD) modifies the association of frailty and mortality following dialysis initiation.

Methods: A single center retrospective cohort of incident PD and HD patients was analyzed from 2009 to 2020 (last follow-up December 2021). The first version of the clinical frailty scale (CFS) ranging from 1, very fit, to 7, severely frail, was used to characterize patient frailty at dialysis initiation. Time to death/transfer to HD was analyzed using multivariable Cox Survival analyses. Patients were censored at transplant/last follow-up. Dialysis modality was evaluated as a potential effect modifier on the impact of frailty on mortality.

Results: Of 253 patients who initiated PD, 182 had completed CFS scores. Mean age at dialysis initiation was 63 ± 13 years and mean CFS score was 3 ± 1. There were 42 deaths and 69 instances of transfer to HD over 379 patient-years at risk. Vulnerable/frail patients (CFS ≥ 4) had a two-fold increase in the adjusted relative hazard for death/transfer to HD (HR 2.04, 95% CI [1.10-3.77]). Incident dialysis modality did not modify the association between frailty and mortality.

Conclusions: A higher severity of frailty at PD initiation is associated with both mortality/transfer to HD and mortality alone, and the association between frailty and mortality is not modified by dialysis modality.