Validation of risk prediction tools in elderly patients who initiate dialysis

Usefulness of the Clinical Frailty Scale in patients with end-stage kidney disease

Background

The frailty index (FI) is commonly used to estimate frailty in end-stage kidney disease (ESKD) patients. The Clinical Frailty Scale (CFS) is a less time-consuming alternative. We aimed to determine the test performance of the CFS for pre-dialysis and dialysis patients and patients receiving conservative therapy from the Dialysis Centre Apeldoorn.

Methods

In this cross-sectional study, haemodialysis, peritoneal dialysis, pre-dialysis patients and patients receiving conservative therapy from the Dialysis Centre Apeldoorn were included and subjected to frailty assessment. Nephrologists not familiar with the CFS completed the frailty score after medical consultation. The sensitivity, specificity and area under the curve (AUC) of the CFS were determined. The FI was used as the gold standard.

Results

Included were 144 patients, of whom 60 (41.7%) were considered frail according to the FI. The mean age was 67.4 ± 13.5 years and 56 (38.9%) were female. The cut-off point of the CFS for 'vulnerable' (CFS ≥4) had a sensitivity of 63.3%, a specificity of 81.0% and an AUC of 0.72. The cut-off point of the CFS for 'frail' (CFS ≥5) had a sensitivity of 50.0%, a specificity of 91.7% and an AUC of 0.71.

Conclusions

The CFS is a quick and easy-to-use tool for the determination of frailty in ESKD patients with a high prevalence of frailty. Nevertheless, the sensitivity of the CFS in the present study was considered too low to implement into daily clinical practice. The sensitivity might be increased by training nephrologists in the use of the CFS.

Use of frailty assessment instruments in nephrology populations: a scoping review

BACKGROUND

Frailty is a clinical syndrome of accelerated aging associated with adverse outcomes. Frailty is prevalent among patients with chronic kidney disease but is infrequently assessed in clinical settings, due to lack of consensus regarding frailty definitions and diagnostic tools. This study aimed to review the practice of frailty assessment in nephrology populations and evaluate the context and timing of frailty assessment.

METHODS

The search included published reports of frailty assessment in patients with chronic kidney disease, undergoing dialysis or in receipt of a kidney transplant, published between January 2000 and November 2021. Medline, CINAHL, Embase, PsychINFO, PubMed and Cochrane Library databases were examined. A total of 164 articles were included for review.

RESULTS

We found that studies were most frequently set within developed nations. Overall, 161 studies were frailty assessments conducted as part of an observational study design, and 3 within an interventional study. Studies favoured assessment of participants with chronic kidney disease (CKD) and transplant candidates. A total of 40 different frailty metrics were used. The most frequently utilised tool was the Fried frailty phenotype. Frailty prevalence varied across populations and research settings from 2.8% among participants with CKD to 82% among patients undergoing haemodialysis. Studies of frailty in conservatively managed populations were infrequent (N = 4). We verified that frailty predicts higher rates of adverse patient outcomes. There is sufficient literature to justify future meta-analyses.

CONCLUSIONS

There is increasing recognition of frailty in nephrology populations and the value of assessment in informing prognostication and decision-making during transitions in care. The Fried frailty phenotype is the most frequently utilised assessment, reflecting the feasibility of incorporating objective measures of frailty and vulnerability into nephrology clinical assessment. Further research examining frailty in low and middle income countries as well as first nations people is required. Future work should focus on interventional strategies exploring frailty rehabilitation.