Comparison of self-report-based and physical performance-based frailty definitions among patients receiving maintenance hemodialysis. American journal of kidney diseases Johansen, K. L., Dalrymple, L. S., Delgado, C., Kaysen, G. A., Kornak, J., Grimes, B., Chertow, G. M. 2014; 64 (4): 600-607

Abstract

A well-accepted definition of frailty includes measurements of physical performance, which may limit its clinical utility.In a cross-sectional study, we compared prevalence and patient characteristics based on a frailty definition that uses self-reported function to the classic performance-based definition and developed a modified self-report-based definition.Prevalent adult patients receiving hemodialysis in 14 centers around San Francisco and Atlanta in 2009-2011.Self-report-based frailty definition in which a score lower than 75 on the Physical Function scale of the 36-Item Short Form Health Survey (SF-36) was substituted for gait speed and grip strength in the classic definition; modified self-report definition with optimized Physical Function score cutoff points derived in a development (one-half) cohort and validated in the other half.Performance-based frailty defined as 3 of the following: weight loss, weakness, exhaustion, low physical activity, and slow gait speed.387 (53%) patients were frail based on self-reported function, of whom 209 (29% of the cohort) met the performance-based definition. Only 23 (3%) met the performance-based definition of frailty only. The self-report definition had 90% sensitivity, 64% specificity, 54% positive predictive value, 93% negative predictive value, and 72.5% overall accuracy. Intracellular water per kilogram of body weight and serum albumin, prealbumin, and creatinine levels were highest among nonfrail individuals, intermediate among those who were frail by self-report, and lowest among those who also were frail by performance. Age, percentage of body fat, and C-reactive protein level followed an opposite pattern. The modified self-report definition had better accuracy (84%; 95% CI, 79%-89%) and superior specificity (88%) and positive predictive value (67%).Our study did not address prediction of outcomes.Patients who meet the self-report-based but not the performance-based definition of frailty may represent an intermediate phenotype. A modified self-report definition can improve the accuracy of a questionnaire-based method of defining frailty.

View details for DOI 10.1053/j.ajkd.2014.03.016

View details for PubMedID 24793033