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Updated: Mar 9, 2026

A Thrombotic Stroke Model Based On Transient Cerebral Hypoxia-ischemia
Published on: August 18, 2015
Sex and Stroke in Thrombolyzed Patients and Controls
Christian Hametner1, Rachael L MacIsaac2, Lars Kellert2
1From the Department of Neurology, Division of Vascular Neurology, University of Heidelberg, Germany (C.H., L.K., P.A.R.); Queen Elizabeth University Hospital (R.L.M., A.H.A.-R.) and BHF Cardiovascular Research Centre (K.R.L.), Institute of Cardiovascular and Medical Sciences, University of Glasgow, United Kingdom; and Department of Neurology, Ludwig-Maximilians-University Munich, Germany (L.K.). Christian.Hametner@med.uni-heidelberg.de.
Background And Purpose:
We hypothesized that any sex-related difference in outcome poststroke is explained by other prognostic factors and that the response to intravenous recombinant tissue-type plasminogen activator (r-tPA) is equal in males and females after adjustment for such factors.
Methods:
We accessed an independent collection of randomized clinical trials-the VISTA (Virtual International Stroke Trials Archive). Data were preprocessed by selecting complete cases (n=8028) and matching females to males (coarsened exact matching, n=4575, 24.3% r-tPA). Outcome was assessed by the 7-point modified Rankin Scale (mRS) measured at 90 days after ischemic stroke. Relationship among variables was estimated by adjusted regression analysis.
Results:
In nonthrombolyzed patients, ordinal analysis of mRS adjusting for stroke- and sex-related prognostic factors suggested comparable outcomes for females and males (odds ratio, 0.96; 95% confidence interval, 0.85-1.06). Females responded comparably to r-tPA as did males, irrespective of the outcome definition of mRS (ordinal: PInteraction=0.46, relative excess risk because of interaction=0). The number needed to treat was 6.8 and 11.2 for 1 female to achieve mRS score of 0 to 2 and 0 to 1, which was highly congruent with males. Analysis for a nonlinear variation of age-by-sex revealed a good outcome for females <45 years with significant disadvantage thereafter (mRS score of 0-2: PInteraction=0.004). No relationship between sex, r-tPA, and bleeding complications was evident.
Conclusions:
Functional outcome (mRS) without r-tPA was overall similar between the sexes, as was the response to r-tPA. Nonlinear sex-by-age interaction improved estimates of functional independence; this should be considered in sex-related studies in stroke.

