Frailty Measures for Adult Patients and Outcomes for Vestibular Schwannoma Surgeries: A Retrospective Cohort Study.

BACKGROUND AND OBJECTIVES: To determine whether preoperative frailty [5-item/11-item modified frailty index (mFI-5/mFI-11)] independently predicts length of stay (LOS) and early facial nerve function after vestibular schwannoma (VS) resection when adjusting for tumor and operative factors at a single center with standardized postoperative care. METHODS: This was a single-center, institutional review board-approved, retrospective review of consecutive adults undergoing microsurgical VS resection from 2014 to 2025. Candidate predictors included mFI-5, mFI-11, age, temporal muscle thickness, tumor size, surgical approach, preoperative nonauditory cranial nerve deficits, immediate postoperative facial nerve function, and ventriculoperitoneal shunt requirement. Primary outcomes were LOS (days) and House-Brackmann (HB) grade at discharge, modeled with negative binomial and cumulative odds ordinal logistic regression, respectively (two-sided α = 0.05). RESULTS: = .017). Substituting individual comorbidities for frailty indices did not materially alter findings. CONCLUSION: In VS microsurgery, tumor size rather than frailty was the dominant correlate of early postoperative outcomes after adjustment. Because frailer patients are often selected out before elective surgery, the null adjusted association does not prove frailty is clinically irrelevant but reflects its limited incremental value among already-fit patients. Counseling should prioritize tumor characteristics and surgical approach. These hypothesis-generating findings warrant prospective multicenter confirmation.