N. Gupta1, M. L. Salter1,2,3, A. Massie1, M. A. McAdams-Demarco1,2, A. H. Law2, B. G. Jaar2, J. D. Walston3, D. L. Segev1,2 1Johns Hopkins University School Of Medicine,Department Of Surgery,Baltimore, MD, USA 2Johns Hopkins University School Of Public Health,Department Of Epidemiology,Baltimore, MD, USA 3Johns Hopkins University,Center On Aging And Health,Baltimore, MD, USA
Introduction: Frailty, a novel domain of risk originally validated in the geriatrics literature, captures poor physiologic reserve. It is a construct that is independent of comorbidity and disability, and it has been shown to be an independent predictor of poor outcomes in the general surgery, transplant, and end-stage renal disease (ESRD) populations. However, frailty is not routinely measured in the clinical setting; instead, we rely on perceptions of frailty to influence clinical decision-making. Whether perceived frailty accurately reflects measured frailty remains unknown.
Methods: We conducted a cross-sectional study of 145 ESRD patients at a single dialysis center in Baltimore, Maryland. We used the Linda Fried criteria of shrinking, weakness, exhaustion, low physical activity, and slow walking speed to measure frailty and classify patients as non-frail, intermediately frail, and frail. We measured provider perceptions of frailty by informing providers (nephrologists and nurse practitioners [NPs]) of the components of frailty and asking them to rate their patients as non-frail, intermediately frail, or frail; we measured patient perceptions of frailty by asking patients to rate their own frailty on this categorical scale. Weighted kappa statistic was used to assess the relationship between measured and perceived frailty. Patient characteristics influencing measured or perceived frailty were evaluated using ordered logistic regression.
Results: Among non-frail participants, 34.4%, 30.0%, and 31.6% were misperceived as intermediately frail or frail by a nephrologist, NP, and themselves. The agreement between measured and perceived frailty was, at best, only slightly better than what would be expected by chance alone (nephrologists: kappa = 0.24; NPs: kappa = 0.27; patients: kappa = 0.07). Older age (adjusted OR [aOR]=1.36, 95% CI: 1.11-1.68, p=0.003 per 5-year increase in age) and greater comorbidity (aOR=1.49, 95% CI: 1.27-1.75, p<0.001 per one additional comorbidity) were associated with greater likelihood of being perceived as frail by a nephrologist. Being non-African American was associated with greater likelihood of being perceived as frail by an NP (aOR=5.51, 95% CI: 3.21-9.48, p=0.003) and by the patient themselves (aOR=4.20, 95% CI: 1.61-10.9, p=0.003). Obesity was associated with less likelihood of being perceived as frail by nephrologists (aOR 0.21, 95% CI: 0.16-0.29, p<0.001) and NPs (aOR 0.44, 95% CI: 0.27-0.72, p=0.001). Disability was the only patient characteristic associated with measured frailty (aOR = 1.47, 95% CI: 1.04-2.08, p=0.029 for each additional ADL difficulty).
Conclusion: Perceived frailty is an inadequate proxy for measured frailty. Patient characteristics associated with perceived frailty differ by rater and are different than those associated with measured frailty. If frailty is to be used to assess risk for adverse outcomes, quantitative frailty assessments rather than perceived frailty should be considered.