ABSTRACT NUMBER: ESOC2026A1601 CLINICAL FRAILTY SCALE, BRAIN FRAILTY AND MODIFIED RANKIN SCALE AS PREDICTORS OF FUNCTIONAL OUTCOME AFTER MECHANICAL THROMBECTOMY

Abstract Background and aims Pre-stroke modified Rankin Scale (mRS) is used to assess baseline function prior to mechanical thrombectomy (MT), but was not designed for this. Both Clinical Frailty Scale (CFS) and baseline imaging features of ‘brain frailty’ have been associated with outcome after stroke. We compared CFS, brain frailty and mRS as predictors of functional recovery after MT. Methods Consecutive patients referred to Nottingham University Hospitals NHS Trust March-September 2024 were included. Pre-stroke mRS was provided by referring trusts. CFS scores were retrospectively determined using the Rockwood Clinical Frailty Scale. Baseline neuroimaging was independently reviewed for brain frailty (Leukoaraiosis, atrophy and old vascular lesion; max 3). Day 90 mRS was obtained through correspondence or telephone follow-up. Data are n (%), mean (SD), median [interquartile range], Spearman’s correlation co-efficient with 2-sided p-values. Results 101 patients were included: age 72 (13.7) years, 76 (75.2%) baseline mRS 0, 13 (12.9%) mRS 1, 11 (10.9%) mRS 2. Median CFS 2 [2,4] and ‘brain frailty’ score 2 [1,3]. Baseline mRS was weakly positively correlated with day 90 mRS: r=0.323, p<0.001. CFS and brain frailty showed stronger positive correlations with day 90 mRS: r=0.397, p<0.001 and r=0.384, p<0.001 respectively. When pooled together CFS + brain frailty showed a stronger positive correlation with day 90 mRS: r=0.429, p<0.001. Conclusions Both clinical and brain frailty appear superior (individually and when combined) to pre-stroke mRS for predicting functional outcome after MT. Prospective clinical and brain frailty assessment should be considered pre-MT to establish whether this improves prediction of outcome after MT. Conflict of interest Arya Vikas: nothing to disclose; Laura Rovazdi: nothing to disclose; Jessica Watling: nothing to disclose; Shruti Contractor: nothing to disclose; Luqman Malik: nothing to disclose; Jason P Appleton: nothing to disclose