Frailty and dialysis initiation

Abstract

Frailty is a physiologic state of increased vulnerability to stressors that results from decreased physiologic reserves or dysregulation of multiple physiologic systems. The construct of frailty has been operationalized as a composite of poor physical function, exhaustion, low physical activity, and weight loss. Several studies have now examined the prevalence of frailty among chronic kidney disease (CKD) or end-stage renal disease (ESRD) patients and have found frailty to be more common among individuals with CKD than among those without. Furthermore, frailty is associated with adverse outcomes among incident dialysis patients, including higher risk of hospitalization and death. Recent evidence shows that frail patients are started on dialysis earlier (at a higher estimated glomerular filtration rate [eGFR]) on average than nonfrail patients, but it remains unclear whether these patients' frailty is a result of uremia or is independent of CKD. The survival disadvantage that has been associated with early initiation of dialysis in observational studies could be mediated in part through confounding on the basis of unmeasured frailty. However, available data do not suggest improvement in frailty upon initiation of dialysis; rather, the trajectory appears to be toward higher levels of dependence in activities of daily living (ADLs) after dialysis initiation. Overall, there are no data to suggest that frail patients derive any benefit from early initiation of dialysis either in the form of improved survival or functional status.

Figure 1

Figure Model of Frailty and Uremia Leading to Dialysis Initiation.