2026 Proffered Presentations
S272: FRAILTY STRATIFICATION BY THE MFI-5 INDEX PREDICTS SERIOUS COMPLICATIONS IN CHORDOMA SURGERY
Mahlet A Mekonnen1; Gabrielle Hovis2; Anubav Chandla1; Aryan Pandey1; Isaac Yang1; 1UCLA, Department of Neurosurgery; 2Barrow Neurological Institute
Background: Frailty has emerged as a critical determinant of perioperative risk, yet its role in rare oncologic conditions like chordoma is underexplored. The 5-factor modified frailty index (mFI-5), derived from ACS NSQIP, uses five comorbidities: hypertension, congestive heart failure, chronic obstructive pulmonary disease, diabetes, and non-independent functional status. While validated in various surgeries, its predictive utility in chordoma, a rare malignancy requiring complex procedures, remains unclear. This study assesses the association between mFI-5 and short-term postoperative outcomes in a large chordoma cohort.
Methods: A retrospective analysis included 1,245 chordoma surgeries with available mFI-5 data, assigning scores (0–5) based on NSQIP comorbidities. Patient characteristics analyzed were age, sex, BMI, and ASA classification. Statistical methods involved correlations, univariate analyses, and stratification by mFI-5 category. Primary outcomes were postoperative complications, a 30-day serious complication composite, morbidity and mortality risk, and hospital length of stay (LOS). Logistic regression analyzed binary outcomes, and linear regression assessed LOS, with AUC for model discrimination.
Results: The cohort was 57.2% male and 42.8% female, with 70.3% classified as ASA Class III. The median age was 64 years (mean 62.9 ± 15.0), mean BMI was 27.6 ± 7.0, and mFI-5 was distributed as: 0 (45.4%), 1 (46.3%), 2 (7.4%), ≥3 (0.9%). The overall complication rate was 38.3%. mFI-5 correlated strongly with age (r = 0.294), ASA class (r = 0.274), and preoperative morbidity probability (r = 0.267; all p < 0.001). Complication rates rose from 36.5% (mFI-5 = 0) to 46.7% (mFI-5 = 2), nearing 100% for mFI-5 ≥3. Morbidity probability increased from 9.7% (score 0) to 28.9% (score 4), and mortality risk from 0.6% (score 0) to 3.7% (score 3). Within 30 days, 19.7% experienced at least one complication; the serious composite affected a substantial subset. Each 1-point mFI-5 rise was linked to higher odds of serious complications (OR 1.34, 95% CI 1.12–1.60; p = 0.001; AUC 0.59), overall morbidity (OR 1.20, 95% CI 1.01–1.43; p = 0.044; AUC 0.53), cardiac arrest (OR 2.99, 95% CI 1.51–5.96; p = 0.0018; AUC 0.72), myocardial infarction (OR 2.91, 95% CI 1.50–5.66; p = 0.0016; AUC 0.70), and pneumonia (OR 1.41, 95% CI 1.06–1.87; p = 0.019; AUC 0.63). Each 1-point increase in mFI-5 predicted a 7.6% longer LOS, though model fit was low (p = 0.061, R² = 0.003). Other significant predictors were morbidity probability, BMI, mortality probability, ASA class, and smoking.
Conclusions: mFI-5 is a valid frailty assessment for chordoma surgery, demonstrating dose-response relationships between scores and adverse outcomes. Patients with mFI-5 ≥2 faced an especially elevated risk, underscoring the value of perioperative optimization in this group. The strong correlations with age, ASA class, and predicted morbidity support the index’s construct validity. Though discrimination was modest, frailty scoring effectively identified those at the highest risk, particularly for cardiac and pulmonary events, justifying mFI-5’s integration into preoperative evaluation to guide risk mitigation in this patient population.
