Validation of the Risk Analysis Index for Evaluating Frailty in Ambulatory Patients

Abstract

BACKGROUND Frailty is a marker of dependency, disability, hospitalization, and mortality in community‐dwelling older adults. However, existing tools for measuring frailty are too cumbersome for rapid point‐of‐care assessment. The Risk Analysis Index (RAI) of frailty is validated in surgical populations, but its performance outside surgical populations is unknown. OBJECTIVE Validate the RAI in ambulatory patients. DESIGN, SETTING, AND PARTICIPANTS Observational cohort study of outpatient surgical clinics within the University of Pittsburgh Medical Center Healthcare System between July 1, 2016, and December 31, 2016. Frailty was assessed using the RAI. Current Procedural Terminology codes following RAI assessment identified patients with and without minor office‐based procedures (eg, joint injection, laryngoscopy). MAIN OUTCOMES AND MEASURES All‐cause 1‐year mortality, assessed by stratified Cox proportional hazard models. RESULTS Of 28,059 patients, 13,861 were matched to a minor, office‐based procedure and 14,198 did not undergo any procedure. The mean (SD) age was 56.7 (17.2) years; women constituted 15,797 (56.3%) of the cohort. Median time (interquartile range 25th‐75th percentile) to measure RAI was 30 (22–47) seconds. Mortality among the frail was two to five times that of patients with normal RAI scores. For example, the hazard ratio for frail ambulatory patients without a minor procedure was 3.69 (95% confidence interval [CI] = 2.51‐5.41), corresponding to 30‐, 180‐, and 365‐day mortality rates of 2.9%, 11.2%, and 17.4%, respectively, compared to 0.3%, 2.3%, and 4.0% among patients with normal RAI scores. Discrimination of mortality (overall, and censored at 30, 180, and 365 days) was excellent, ranging from c = 0.838 (95% CI = 0.773‐0.902) for 30‐day mortality after minor procedures to c = 0.909 (95% CI = 0.855‐0.964) without a procedure. CONCLUSION RAI is a valid, easily administered tool for point‐of‐care frailty assessment in ambulatory populations that may help clinicians and patients make better informed decisions about care choices—especially among patients considered high risk with a potentially limited life span.