Sex differences in outcomes after endovascular treatment of patients with vertebrobasilar artery occlusion

Background: Current studies on the role of sex in the prognosis of acute vertebrobasilar artery occlusion (VBAO) are limited. We aimed to explore whether there are sex differences on outcomes in patients treated with endovascular therapy (EVT) for VBAO. Methods: Patients from December 2015 to December 2018 with acute VBAO within 24 h of the estimated occlusion time in 21 stroke centers in China were retrospectively analyzed. Baseline data between sexes were compared in the total population cohort and propensity score (PS)-matched cohort. Multivariate logistic regression and ordinal regression were used to analyze the association of sex with outcomes. Mixed-effects regression model was performed for changes in modified Rankin Scale (mRS) scores in men and women from 90 days to 1 year after discharge. Results: A total of 577 patients (28.4% women) were finally included. Multivariate logistic regression showed that women had a lower probability of favorable outcome (mRS score 0-3 at 90 days; OR 0.544; 95% CI 0.329-0.899) and functional independence (mRS score 0-2 at 90 days; OR 0.391; 95% CI 0.228-0.670) as well as a higher possibility of shifting to worse mRS (OR 1.484; 95% CI 1.020-2.158) than men. After PS matching, 391 patients (39.4% women) were analyzed, confirming the same results regarding favorable outcome (OR 0.580; 95% CI 0.344-0.977), functional independence (OR 0.394; 95% CI 0.218-0.712), and shift mRS (OR 1.504; 95% CI 1.023-2.210). However, the results of repeated ANOVA showed that men and women had a comparable functional recovery from 90 days to 1 year. Conclusions: Stroke due to VBAO treated with EVT is associated with worse outcomes in women than in men. However, men and women showed similar long-term improvement trends.