Structural Integrity of Normal Appearing White Matter and Sex-Specific Outcomes After Acute Ischemic Stroke.
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ABSTRACT: Background and purpose
Women have worse poststroke outcomes than men. We evaluated sex-specific clinical and neuroimaging characteristics of white matter in association with functional recovery after acute ischemic stroke.Methods
We performed a retrospective analysis of acute ischemic stroke patients with admission brain MRI and 3- to 6-month modified Rankin Scale score. White matter hyperintensity and acute infarct volume were quantified on fluid-attenuated inversion recovery and diffusion tensor imaging MRI, respectively. Diffusivity anisotropy metrics were calculated in normal appearing white matter contralateral to the acute ischemia.Results
Among 319 patients with acute ischemic stroke, women were older (68.0 versus 62.7 years; P=0.004), had increased incidence of atrial fibrillation (21.4% versus 12.2%; P=0.04), and lower rate of tobacco use (21.1% versus 35.9%; P=0.03). There was no sex-specific difference in white matter hyperintensity volume, acute infarct volume, National Institutes of Health Stroke Scale, prestroke modified Rankin Scale score, or normal appearing white matter diffusivity anisotropy metrics. However, women were less likely to have an excellent outcome (modified Rankin Scale score <2: 49.6% versus 67.0%; P=0.005). In logistic regression analysis, female sex and the interaction of sex with fractional anisotropy, radial diffusivity, and axial diffusivity were independent predictors of functional outcome.Conclusions
Female sex is associated with decreased likelihood of excellent outcome after acute ischemic stroke. The correlation between markers of white matter integrity and functional outcomes in women, but not men, suggests a potential sex-specific mechanism.
SUBMITTER: Etherton MR
PROVIDER: S-EPMC5726524 | biostudies-literature | 2017 Dec
REPOSITORIES: biostudies-literature
Publications
Structural Integrity of Normal Appearing White Matter and Sex-Specific Outcomes After Acute Ischemic Stroke.
Etherton Mark R MR Wu Ona O Cougo Pedro P Giese Anne-Katrin AK Cloonan Lisa L Fitzpatrick Kaitlin M KM Kanakis Allison S AS Boulouis Gregoire G Karadeli Hasan H HH Lauer Arne A Rosand Jonathan J Furie Karen L KL Rost Natalia S NS
Stroke 20171110 12
<h4>Background and purpose</h4>Women have worse poststroke outcomes than men. We evaluated sex-specific clinical and neuroimaging characteristics of white matter in association with functional recovery after acute ischemic stroke.<h4>Methods</h4>We performed a retrospective analysis of acute ischemic stroke patients with admission brain MRI and 3- to 6-month modified Rankin Scale score. White matter hyperintensity and acute infarct volume were quantified on fluid-attenuated inversion recovery an ...[more]
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