The 5-Item Modified Frailty Index as a Predictor of Postoperative Outcomes in Thoracic Metastatic Epidural Spinal Cord Compression

Abstract

BackgroundPatients with thoracic metastatic epidural spinal cord compression (MESCC) often undergo extensive surgical decompression to avoid functional decline. Though limited in scope, scales including the revised cardiac risk index (RCRI) are used to stratify surgical risk to predict perioperative morbidity. This study uses the 5-item modified frailty index (mFI-5) to predict outcomes following transpedicular decompression/fusion for high-grade MESCC. MethodsA retrospective chart review was conducted on patients who underwent transpedicular decompression and fusion for MESCC (baseline demographics, spinal instability neoplastic score, preoperative and postoperative Bilsky scores, primary cancer type, RCRI). Primary outcomes included length of stay (LOS), intraoperative estimated blood loss, readmission/reoperation within 90 days of index surgery, 90-day mortality, and post-hospitalization disposition. Results127 patients were included in our study. 90% of patients’ lesions were Bilsky 2 or greater. Increasing frailty, measured by mFI-5, was a significant predictor of increased LOS (p<0.01) and 90-day mortality (p<0.05). Multivariate analysis adjusting for sex, BMI, and age still showed statistical significance (p<0.05). MFI-5 was not a significant predictor of readmission/reoperation within 90 days or estimated blood loss. Age – not mFI-5 or RCRI – was a significant predictor for posthospitalization non-home disposition (p=0.001). ConclusionsThe mFI-5 can serve as a useful predictor of outcomes after transpedicular decompression and fusion for thoracic MESCC as it can account for the patient's frailty. Our study demonstrated the mFI-5 as a predictor of LOS and 90-day mortality. These results provide a background to both understanding and integrating frailty into decision-making in MESCC.