Acute astrocytic reaction is associated with 3-month functional outcome after stroke treated with endovascular therapy

Introduction: More than 50% of large vessel occlusion (LVO) acute ischemic stroke (AIS) patients treated with endovascular therapy (EVT) remain severely disabled at 3 months. We hypothesized that acute astrocytic inflammatory response may play a pivotal role in post-AIS brain changes associated with poor functional outcome. We proposed to evaluate the level of YKL-40, a glycoprotein mainly released by reactive astrocytes.Patients and methods: A monocentric prospective cohort study was conducted on consecutive LVO AIS patients treated with EVT. Three blood samples (before, within 1 and 24-hour post-EVT) were collected to measure plasma YKL-40 concentrations. Functional outcome was assessed according to the modified Rankin Scale (mRS) score at 3 months.Results: Between 2016 and 2020, 120 patients were included. The plasma concentration of YKL-40 before EVT was statistically and independently associated with 3-month worse functional outcome (adjusted cOR, 1.59; 95% CI [1.05-2.44], p = 0.027) but not the two following samples 1-hour and 24-hour post-EVT. Accordingly, we found that excellent functional outcome was associated with a lower level of YKL-40 before and within 1 h after EVT (p = 0.005 and p = 0.003, respectively) but not when measured 24 h after EVT (p = 0.2).Discussion and conclusion: This study suggests that the astrocytic reaction to acute brain hypoxia, especially before recanalization, is associated with worse functional outcome. Such early biomarker of the astrocytic response in AIS may optimize individualized care in the future.Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT02900833. Graphical abstract