An Overview of Frailty in Kidney Transplantation

Measurement, Management and Future Considerations

Meera N. Harhay; Maya K. Rao; Kenneth J. Woodside; Kirsten L. Johansen; Krista L. Lentine; Stefan G. Tullius; Ronald F. Parsons; Tarek Alhamad; Joseph Berger; XingXing S. Cheng; Jaqueline Lappin; Raymond Lynch; Sandesh Parajuli; Jane C. Tan; Dorry L. Segev; Bruce Kaplan; Jon Kobashigawa; Darshana M. Dadhania; Mara A. McAdams-DeMarco


Nephrol Dial Transplant. 2020;35(7):1099-1112. 

In This Article

Identifying Frailty in KT Candidates and Recipients

Instruments to Measure Frailty

Although there is an agreement regarding the underlying conceptual framework of frailty, there is a low level of consensus regarding the constituent elements to be included in operational definitions of frailty.[12,13] At least 67 different frailty scales have been used in population-based studies,[14,15] and there is similar heterogeneity in studies of patients with ESKD.[16] In Table 1, we summarize a nonexhaustive list of the available frailty instruments that have been applied to populations with chronic kidney disease (CKD), dialysis dependence and KT. Instruments were included if they have been applied to patients with ESKD in at least one study of prevalence and/or outcome prediction. As in the geriatric arena, the PFP, originally described by Fried et al. in 2001,[17] has emerged as the most commonly applied frailty assessment in studies of patients with ESKD.[16] The PFP includes five domains: weakness, slowness, unintentional weight loss, exhaustion and low physical activity. Individuals who meet three or more of these criteria are at high risk of adverse outcomes when faced with health stressors. A number of factors such as advancing age, comorbidities, polypharmacy and malnutrition contribute to this phenotype among individuals with ESKD, exacerbating vulnerability to illness and to treatment interventions such as dialysis, transplant surgery and immune therapy (Figure 1 ).

Figure 1.

Frail individuals are most vulnerable to the numerous health stressors of kidney disease.

Although there are several validated, self-reported instruments that are simpler to apply in clinical settings than the PFP [e.g. the Kidney Disease Quality of Life Short Form Physical Component Subscale (SF-12 PCS)],[51] there are potential trade-offs in utilizing assessments that may not directly assess physiologic reserve. Conversely, as the KT evaluation setting might make some patients reluctant to reveal the extent of their functional limitations to KT providers, a purely objective frailty instrument, such as the Short Physical Performance Battery,[52] may be desirable. The vast number of available frailty metrics and the differences between them underscore the importance of developing more unified measures to assess vulnerability across the broad population of KT candidates and recipients.

In a national survey of 133 KT centers representing 79% of all adult KT candidates in the USA,[53] there was substantial heterogeneity in the metrics used in clinical settings to assess pre-KT frailty (n = 18 distinct metrics). The majority of centers (67%) reported utilizing more than one frailty metric in their transplant evaluation process and the most common metric utilized by KT centers was a timed walk test (19%) (Table 1). The variability in KT center practices with respect to measurement and utilization of frailty instruments is likely a result of the lack of consensus in the transplant community about how frailty should be assessed. Accordingly, a recent AST consensus statement opined that organ system–specific frailty assessments are likely needed.[4]