1218 Frailty is an Independent Predictor of Morbidity and Mortality in Spine Surgeries: A Population-Wide 15-Year Follow-Up Retrospective Study

INTRODUCTION: Frailty is a known correlate of poor outcomes following spine surgery. However, long-term outcomes are not well-studied. METHODS: TriNetX Research Network was queried by CPT for patients undergoing the 13 most common spine surgeries. Patients were propensity score matched to control for age, sex, and race. Kaplan-Meier plots were used to evaluate differences in survival and Clavien-Dindo Grade IV complications (unplanned intubation, prolonged ventilation, pulmonary embolism, acute kidney failure, stroke, myocardial infarction, cardiac arrest, septic shock) between severely frail (modified frailty index [mFI] >=3) and non-severely frail (mFI<3) patients. RESULTS: 998,973 patients were identified. 224,889 (22.5%) had an mFI >=3, and 774,027 (77.5%) had an mFI <3. The average age was 65.9 years old ± 11.4 years for the mFI ³3 group and 55.5 years old ± 14.8 years for the mFI <3 group. After matching for age, sex, and race, 449,778 patients were included. Severe frailty was an independent predictor of mortality (HR2.491, 95%CI 2.431-2.552, p<0.0001) and Clavien-Dindo grade IV complications (HR 4.100, 95%CI 4.040-4.161, p<0.0001) up to 15 years after surgery. The presence of any single disease included in the mFI-5 was also a predictor of severe complication (HR2.648, 95%CI 2.551-2.748, p<0.0001). CONCLUSIONS: Severe frailty is an independent predictor of morbidity and mortality up to 15 years post-operatively in patients undergoing spine surgery. Severely frail patients are 2.5 times more likely to die and 4.1 times more likely to experience a serious complication. Even 15 years after surgery, complications typically associated with the post-operative period are more likely to occur in patients who have any degree of frailty.