426 Utility of the Fried Phenotype as a Frailty Assessment Tool in Predicting Post-Operative Outcomes in Lumbar Degenerative Spine Surgery Patients

Abstract

INTRODUCTION: Frailty is a syndrome of physiological decline that can predispose surgical patients to increased peri-operative morbidity. The Fried phenotype is a clinical measure of frailty and categorizes patients’ frailty based on grip strength, walking speed, unintentional weight loss, low physical activity, and exhaustion. It has been validated in non-spine surgical populations and has been shown to be correlated with poor postoperative outcomes and longer hospital lengths of stay (LOS); it has not yet been validated in patients undergoing spine surgery. Other assessment tools, including the Modified Frailty Index-11 (mFI-11) and Charlson Comorbidity Index (CCI), are calculated based on comorbidities. The mFI-11 has previously been studied in spine patients - a higher mFI-11 score has been associated with a higher risk of post-operative morbidity and mortality. METHODS: Patients >65 years of age who underwent elective lumbar spine surgery for degenerative disease since 2015 were included. Data for the Fried phenotype, mFI-11, CCI, and outcomes were gathered for each patient. ROC curves were generated, and multivariate analyses were performed. RESULTS: 248 patients (128 females; 120 males) with an average age of 71.8 years were included. The median Fried score was 1, median CCI was 1, and median mFI-11 was 0.18. The median LOS was 4 days, with 11 30-day re-admissions. Fried phenotype was found to be the best predictor of an extended LOS and of a non-home discharge. CONCLUSIONS: The Fried phenotype is now shown to be a validated measure of frailty in the spine population. Because it relies on categories that are impacted by the patient's functional condition (instead of the comorbidity burden), it has profound implications for optimizing patients through pre-habilitation prior to elective surgery.