#1454 Usefulness of the clinical frailty scale in Dutch patients with end-stage kidney disease
Authors: Lamberdink Kyra , Vermeeren Yolande , Moes Arthur , Mulderij Jeanette , Rootjes Paul , Zomer Tizza 
Published: May 2024

Abstract

Background and Aims
Frailty is common in end-stage kidney disease (ESKD) patients which may benefit from advance care planning. Currently there are multiple frailty screening instruments available, of which the Frailty Index is commonly used to estimate frailty in ESKD patients. The Clinical Frailty Scale is a less time consuming alternative to estimate frailty. We aimed to investigate the performance of the Clinical Frailty Scale as a screening tool for frailty in an ESKD population.

Method
A cross-sectional observational study was performed at Kidney Centre Apeldoorn. Included patients received haemodialysis, peritoneal dialysis, pre-dialysis care, or conservative treatment. Frailty was assessed with both the Frailty Index and the Clinical Frailty Scale. The Frailty Index consisted of 38 components considering activities of daily living, physical aspects, psychosocial factors, comorbidities, and functional tests. The functional tests included grip strength, walking speed, and cognitive functioning measured by the Mini Mental State Examination. The Frailty Index was calculated by dividing the number of deficits by the total number of components measured. A patient with a Frailty Index ≥0.25 was considered frail.
The Clinical Frailty Scale consisted of nine classes varying from very fit to terminally ill. Patients who scored 4 on the Clinical Frailty Scale were considered vulnerable. Patients with a score ≥5 were considered frail. Nephrologists not familiar with the Clinical Frailty Scale were asked to complete the Clinical Frailty Scale after medical consultation. The sensitivity, specificity and area under the curve (AUC) of the Clinical Frailty Scale were determined. The Frailty Index was used as the golden standard.

Results
In total, 144 patients were included of whom 60 (41.7%) were frail according to the Frailty Index. The mean age was 67.4 years (SD±13.5) and 56 (38.9%) were female. Overall, 72 patients (50.0%) were treated by haemodialysis, 13 (9.0%) by peritoneal dialysis, 6 (4.2%) received conservative treatment, and 53 (36.8%) were pre-dialysis patients. According to the Frailty Index, 55.6% of the haemodialysis patients were frail compared to 20.8% of the pre-dialysis patients.
The Clinical Frailty Scale identified 37 (25.7%) patients as frail and 17 (11.8%) patients as vulnerable. The cut-off point of the Clinical Frailty Scale for vulnerable (≥4) had a sensitivity of 63.3%, a specificity of 81.0%, and AUC of 0.72. The cut-off point of the Clinical Frailty Scale for frail (≥5) had a sensitivity of 50.0%, a specificity of 91.7%, and AUC of 0.71.

Conclusion
Prevalence of frailty was high in patients with ESKD. Although the Clinical Frailty Scale is a quick and easy tool for the identification of frailty in ESKD patients, the sensitivity of the Clinical Frailty Scale was too low to implement it in daily clinical practice. Sensitivity might be increased by training of nephrologists in using the Clinical Frailty Scale.