Sex differences in Outcomes After Mechanical Thrombectomy for Acute Ischemic Stroke: Real-World Analysis and Literature Review

Abstract Objective: To investigate the effect of sex on outcomes after mechanical thrombectomy (MT) for acute ischemic stroke (AIS) in a real-world setting.Methods: AIS patients receiving anterior circulation MT from our tertiary care academic institution were retrospectively reviewed and analyzed. Additionally, a literature review and meta-analysis regarding the impact of sex on MT outcomes was performed. Favorable outcome (90-day mRS 0-2), mortality, intracranial hemorrhage (ICH) and symptomatic ICH (sICH) were compared.Results: 1) From January 2019 to December 2021, a total of 347 AIS patients were recruited, including 126 females and 221 males. Before adjustment, females had a lower rate of favorable outcome (41.3% vs. 52.9%, P=0.037) and a higher rate of mortality (21.3% vs. 11.3%, P=0.867), but the difference was not significant after adjustment. ICH and sICH did not differ comparing females and males. 2) The systematic review and meta-analysis incorporated 8 eligible studies (3129 females and 3383 males), including our original data. A similar phenomenon was demonstrated; females were less likely to have a favorable outcome (OR 0.58, 95%CI 0.45-0.75, I2=77.3% ) and had a higher mortality (20.9% vs. 17.1%, OR 1.24, 95%CI 1.06-1.44, I2=12.4) before adjustment, but there were comparable outcomes after pooling adjusted data (favorable outcome: aOR 0.85, 95%CI 0.71-1.02, I2=63.8%; mortality: aOR 0.85, 95%CI 0.65-1.12, I2=33.6%). There was no significant difference in ICH and sICH.Conclusions: Females showed a worse functional outcome after MT for AIS in a real-world setting, but sex innately is not a predictor of outcome after adjustment by confounding factors.