The Influence of Sex in Stroke Thrombolysis: a Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE: There is increasing recognition of the importance of stroke in females to both clinical and public health. The natural course of stroke is worse in females than in males, but the evidence regarding sex disparities in the responses to thrombolysis in stroke patents is still controversial. We compared outcomes after thrombolysis treatment between females and males. METHODS: Clinical trials reported in the Embase, PubMed, and Cochrane Library electronic databases up to March 13, 2017 were included in this analysis. Two reviewers independently extracted the data and conducted quality assessments. Statistical tests were performed to check for heterogeneity and publication bias. Sensitivity analysis was also performed to evaluate the stability of the conclusions. RESULTS: Sixteen reports involving 60,159 patients were available for analysis. The female patients were a 0.89-fold [95% confidence interval (CI)=0.87-0.90, p<0.001], 0.89-fold (95% CI=0.87-0.91, p<0.001), and 1.24-fold (95% CI=1.11-1.36, p<0.001) more likely to obtain good, excellent, and poor functional outcomes, respectively, with no significant difference in the complications of symptomatic intracranial hemorrhage among the sexes [risk ratios (RR)=0.99, 95% CI=0.92-1.07, p=0.81] after thrombolysis treatment. In addition, the prevalence of a good functional outcome did not differ significantly between females and males in the intra-arterial thrombolysis (IAT) group (RR=1.05, 95% CI=0.85-1.29, p=0.67) in a subgroup analysis. CONCLUSIONS: This study has demonstrated that females often exhibit a worse outcome than males after intravenous thrombolysis (IVT), whereas no relevant sex differences were found in outcome or recanalization after IAT, with safety regarding hemorrhage complications from thrombolysis being the same for the sexes. However, IVT should not be withheld from female stroke patients solely based on their sex before the findings are confirmed in further large-scale research.