The BAND score: a simple model for upfront prediction of poor outcomes despite successful stroke thrombectomy

BACKGROUND:While endovascular thrombectomy (EVT) is beneficial for patients with acute large vessel occlusion ischemic strokes, a significant portion of patients still do poorly despite successful recanalization. Identifying patients at high risk for poor outcomes can be helpful for future clinical trial design and optimizing acute stroke triage. METHODS:Consecutive EVT patients were identified from 2016 to 2021 at a Comprehensive Stroke Center, and clinical information was recorded. Poor outcome was defined as a 90-day modified Rankin Scale (mRS) of 4 or greater despite achieving a modified thrombolysis in cerebral infarction (mTICI) score of 2b or greater. Multivariable regression analyses were used to identify risk factors for poor outcomes, and a scoring system was constructed. RESULTS:483 patients with successful recanalization were identified. From a randomly selected training cohort (n=357), the 10-point BAND score was constructed from independent risk factors for poor outcomes: baseline disability (1 point: baseline mRS ≥ 2), age (1 point: 60-69 years, 2 points: 70-79 years, 3 points: 80-84 years, 4 points: 85 years or older), NIHSS (2 points: 13-17, 3 points: 18-22, and 4 points: ≥ 23), and delay from last known normal (1 point: ≥ 6 hours). The BAND score was significantly associated with rates of poor outcomes (p<0.001), and it achieved an area under the receiver-operating characteristic curve (AUC) of 0.80 (95%CI 0.76-0.85) in our training cohort and 0.78 (95%CI 0.70-0.86) in our validation cohort (n=126). Overall, the BAND score had a significantly higher AUC value than the widely validated THRIVE score and the THRIVE-EVT calculation (p=0.001 and 0.029, respectively). Among patients with high BAND scores (7 or higher), 88.2% had poor outcomes. CONCLUSION:The BAND score is a simple tool to predict poor outcomes despite successful recanalization. Future studies are needed to confirm the BAND score's external validity.