Prognostic significance of walking ability at hospital discharge for overall survival in newly diagnosed glioblastoma: a comparison across six peri-treatment assessments.

PURPOSE: Walking ability is readily assessed at the bedside; however, whether it adds prognostic information beyond global performance status in glioblastoma (GBM) is unknown. We examined the Functional Ambulation Category (FAC) at six peri-treatment time points and whether discharge FAC is associated with overall survival (OS) independently of contemporaneous performance status. METHODS: This retrospective single-center study included 185 adults with newly diagnosed GBM treated from 2011 to 2020. FAC was assessed preoperatively, on postoperative day 5, before chemoradiotherapy, at discharge, and 1 and 4 months after discharge. The primary analysis used a discharge landmark, with FAC grouped as 0-1, 2-4, and 5 and adjustment for age, sex, extent of resection, and discharge Karnofsky Performance Status (KPS). Incremental performance was assessed using Akaike information criterion (AIC) and Harrell's C-index. RESULTS: Higher FAC was associated with longer OS at all six time points, with the strongest univariable association at discharge. In the discharge-landmark model (n = 162; 138 deaths), adjusted hazard ratios versus FAC 0-1 were 0.45 (95% CI, 0.27-0.73) for FAC 2-4 and 0.33 (95% CI, 0.17-0.63) for FAC 5. Adding FAC improved fit and discrimination (ΔAIC, - 8.4; ΔC-index, + 0.022; p = 0.002). Estimates were unchanged after additional adjustment for bevacizumab and post-discharge temozolomide. CONCLUSION: Discharge FAC carries prognostic information not captured by contemporaneous global performance status and is a practical bedside marker at the transition to post-discharge care, rather than a stand-alone prediction tool. REGISTRATION: This study was not prospectively registered. PROTOCOL: No prospective study protocol was prepared.