Development and Evaluation of a New Frailty Index for Older Surgical Patients With Cancer

IMPORTANCE Frailty based on the modified Frailty Index is associated with poor postoperative outcomes. However, the index requires high levels of personnel time and effort and often has missing data. OBJECTIVE To evaluate the association of the Memorial Sloan Kettering-Frailty Index (MSK-FI) with established geriatric assessment (GA) and surgical outcomes. DESIGN, SETTING, AND PARTICIPANTS This cohort study included prospectively evaluated patients with cancer 75 years and older who were referred to MSK Geriatrics Service clinics for preoperative evaluation before undergoing surgery requiring hospitalization between February 2015 and September 2017. Patients were comanaged by the Geriatrics Service and Surgery Service in the postoperative period. EXPOSURES Impairments identified by GA and comorbid conditions retrieved from submitted International Classification of Diseases, Ninth Revision (ICD-9) and ICD-10 codes within the first 48 hours of hospitalization. MAIN OUTCOMES AND MEASURES The association of MSK-FI score (which included ICD-9 and ICD-10 codes) with GA impairments (based on clinical interview and examination as well as patient reports) was examined. The associations of MSK-FI score with short-term surgical outcomes (ie, frequency of complications, length of stay, 30-day surgical complications, 30-day intensive care unit admissions, and 30-day readmissions) and 1-year survival, estimated by Kaplan-Meier methods, were determined. RESULTS In total, 1137 patients (median [interquartile range] age, 80 [77-84] years; 583 [51.2%] women) were included in the study. A higher MSK-FI score was associated with the number of GA impairments (rho = 0.52; bootstrapped 95% CI, 0.47-0.56). Each 1-point increase in MSK-FI score was associated with longer length of stay (0.58 d; 95% CI, 0.22-0.95; P = .002) and higher odds of intensive care unit admission (odds ratio, 1.28; 95% CI, 1.04-1.58; P = .02). Median (interquartile range) follow-up among survivors was 12.1 (5.6-19.1) months. The MSK-FI score was associated with overall mortality; 12-month risk of death was 5% for a score of 0 and approximately 20% for scores of 4 and higher (nonlinear association, P = .005). CONCLUSIONS AND RELEVANCE In this study, the MSK-FI was associated with the previously validated GA and postoperative outcomes in older patients with cancer and may be a feasible tool for perioperative assessment of older surgical patients with cancer. Future studies should assess the association of MSK-FI score with postoperative care and outcomes of older, frail patients with cancer.