366 Frailty Is a Risk Factor for Mortality in Operative and Non-operative Type II Odontoid Fracture Patients: An ACS-TQIP Survival Analysis of 22,440 Patients

INTRODUCTION: Type II Odontoid Fractures (T2OF) are the most prevalent cervical spine fractures in adults =65 years old. Nonetheless, there is insufficient data regarding the influence of frailty on outcomes for both nonoperative and operative, treatment approaches. METHODS: We conducted a retrospective review of T2OF patients from 2015 to 2020 using the ACS-TQIP® database. Using unmatched and propensity score-matched (PSM) risk-adjusted models we assessed the association between frailty and all adverse outcomes. Survival probabilities were examined using Kaplan-Meier (K-M) plots and frailty-based risk stratification. Our outcomes include major complications, hospital length of stay (LOS), nonhome discharge (NHD), mortality rates, and survival probabilities. RESULTS: There were 22,440 T2OF patients, comprised of 31.8% (n = 7,138) robust, 35.2% (n = 7,913) typical, 22.9% (n = 5,158) frail, and 9.9% (n = 2,231) very frail patients. Results from unmatched multivariable analyses revealed a dose-dependent relationship between frailty and all outcomes, in both cohorts (p < 0.05). PSM resulted in 3,942 nonoperative and operative matched pairs. Preoperative characteristics were similar between cohorts, except for age: 75 years (IQR: 60-83) nonoperative and 70 years (IQR: 56-78) operative, and male sex: nonoperative 1,799 (55.8%) and operative 439 (61.1%). Significant mortality reductions (43-77%; p < 0.05) were observed in the operative cohort compared to the nonoperative cohort across all frailty strata. As expected, the operative cohort had longer LOS and increased NHD risk ranging from 64-97%, p < 0.001. In K-M analyses, survival declined significantly across increasing frailty strata p < 0.001. CONCLUSIONS: Increasing frailty in T2OF patients was independently associated with major complications, LOS, NHD, and decreased survival. Interestingly, operative patients exhibited improved survival compared to nonoperative patients across all frailty strata. These findings highlight the importance of frailty in T2OF management and care coordination.