Supplementary Material for: Successful Reperfusion with Endovascular Therapy Has Beneficial Effects on Long-Term Outcome Beyond 90 Days

Background and Purpose: Recent studies have demonstrated that endovascular reperfusion therapy improves clinical outcomes at 90 days after ischemic stroke. However, the effects on long-term outcomes are not well known. We hypothesized that successful reperfusion might be associated with long-term improvement beyond 90 days after endovascular therapy. To assess the long-term effects beyond 90 days, we analyzed the association of successful reperfusion with a temporal change in modified Rankin Scale (mRS) score from 90 days to 1 year after endovascular therapy. Methods: We retrospectively analyzed a database of consecutive patients with acute ischemic stroke who received endovascular therapy between April 2006 and March 2016 at 4 centers. We compared the incidences of improvement and deterioration in patients with successful reperfusion (i.e., modified thrombolysis in cerebral infarction score of 2b or 3) with those in patients with unsuccessful reperfusion. We defined improvement and deterioration as decrease and increase on the mRS score by 1 point or more from 90 days to 1 year after endovascular therapy respectively. Results: A total of 268 patients were included in the current study. The rate of patients with improvement tended to be higher in patients with successful reperfusion than in patients with unsuccessful reperfusion (20% [34/167 patients] vs. 12% [12/101], p = 0.07). The rate of patients with deterioration was lower in patients with successful reperfusion than in patients with unsuccessful reperfusion (25% [42/167] vs. 42% [42/101], p < 0.01). After adjustment for confounders, successful reperfusion was associated with improvement (adjusted OR 2.65; 95% CI 1.23–5.73; p < 0.05) and deterioration (adjusted OR 0.33; 95% CI 0.18–0.62; p < 0.01), independent of the 90-day mRS score. Conclusions: Successful reperfusion has further beneficial legacy effects on long-term outcomes beyond 90 days after stroke.