Clinical Effects of Early Edaravone Use in Acute Ischemic Stroke Patients Treated by Endovascular Reperfusion Therapy

Background and Purpose— Although several clinical studies suggested the beneficial effects of edaravone in acute ischemic stroke, most were performed under settings that differ from those in the current treatment strategy, which has dramatically changed with progress in reperfusion therapies. This study aimed to evaluate the efficacy of edaravone in patients with acute ischemic stroke treated by emergent endovascular reperfusion therapy. Methods— We conducted a retrospective observational study using a national administrative database. Patients with acute ischemic stroke treated by emergent endovascular reperfusion therapy were identified and dichotomized by whether edaravone was used within 2 days of admission. We compared the functional independence at hospital discharge, in-hospital mortality, and intracranial hemorrhage after admission between groups, adjusted by a well-validated case-mix adjustment model, in multivariate mixed-effect regression and propensity score matching analyses. Results— Of 11 508 patients eligible for analysis, 10 281 (89.3%) received edaravone therapy. The established risk adjustment model had good predictability for functional independence at hospital discharge, with an area under the receiver operating characteristic curve of 0.74. In the mixed-effect regression analysis, edaravone use was significantly associated with greater functional independence at hospital discharge (32.3% in the edaravone group versus 25.9% in the control group; adjusted odds ratio, 1.21; 95% confidence interval, 1.03–1.41), lower in-hospital mortality (9.9% in the edaravone group versus 17.4% in the control group; adjusted odds ratio, 0.52; 95% confidence interval, 0.43–0.62), and reduced intracranial hemorrhage after admission (1.4% in the edaravone group versus 2.7% in the control group; adjusted odds ratio, 0.55; 95% confidence interval, 0.37–0.82). Results of the propensity score matching analysis corroborated these results. Conclusions— This retrospective analysis of a Japanese nationwide administrative database suggested that combination therapy with edaravone and endovascular reperfusion therapy could be a promising therapeutic strategy in acute ischemic stroke. Further randomized control trials are warranted.