Comparison of Frailty Index to Pneumonia Severity Measures in Older Patients With Pneumonia

Abstract

Risk stratification tools are useful to provide appropriate clinical care for older patients with pneumonia. This study aimed to compare a Frailty Index (FI) with pneumonia severity measures, CURB-65, and the Pneumonia Severity Index (PSI), for predicting mortality and persistent disability after pneumonia. Single-center prospective cohort study. The study included 190 patients aged ≥65years who were hospitalized with pneumonia at a university hospital in Korea between October 2019 and September2020. At admission, a 50-item deficit-accumulation FI (range: 0-1), CURB-65 (range: 0-5), and PSI (range: 0-395) scores were calculated. The outcomes were death and a composite outcome of death or decline in ability to perform daily activities and physical task 6months later. The median age was 79years (interquartile range: 74-85), and 70 (36.8%) patients were women. The patients who died (n= 53) had higher FI (median, 0.46 vs 0.20; P < .011), CURB-65 score (median, 3 vs 2; P= .001), and PSI score (median, 149 vs 116; P < .001) than those who did not. The C-statistics (95% confidence intervals) for 6-month mortality were 0.69 (0.61-0.77) for the FI, 0.62 (0.53-0.71) for CURB-65, and 0.71 (0.62-0.79) for the PSI (P= .019). The C-statistics for the 6-month composite outcome were 0.73 (0.65-0.81) for the FI, 0.64 (0.55-0.73) for CURB-65, and 0.69 (0.60-0.77) for the PSI (P= .096). The C-statistics improved when the FI was added to CURB-65 (from 0.64 to 0.74; P= .003) and to the PSI (from 0.69 to 0.75; P= .044) for the composite outcome. Measuring frailty provides additive value to widely used pneumonia severity measures in predicting death or persistent hospitalization-associated disability in older adults after pneumonia hospitalization. Early recognition of frailty may be useful to identify those who require in-hospital and post-acute care interventions for functional recovery.