title: Sex and Hemisphere - A Neglected, Nature-Determined Relationship in Acute Ischemic Stroke.
abstract: BACKGROUND
  Sex differences in the structural connectome of the brain are clinically highly relevant, but they have mostly been neglected in stroke trials. We investigated the impact of the interaction sex-by-hemisphere on outcome in stroke patients after intravenous thrombolysis (IVT).
  
  
  METHODS
  This is an observational study based on consecutively collected supratentorial stroke patients treated with IVT (n = 1,231). The 3-month modified Rankin scale (mRS) was estimated by adjusted binary (mRS 0-2 for good outcome) and ordinal regression analysis. As baseline characteristics differ substantially between the sexes, we aimed for better covariate balance by employing coarsened exact matching.
  
  
  RESULTS
  Sex-by-hemisphere predicted good outcome in the entire cohort (726 left, 505 right hemispheric strokes, p valueinteraction 0.032) and in the matched cohort (338 left, 273 right, p valueinteraction 0.003). Ordinal regression suggested a comparable estimate in the matched cohort (p valueinteraction 0.006). Further investigation revealed relevant between-sex and within-sex risk: right hemispheric strokes in men were 1.54 times (95% confidence intervals (CIs) 1.15-2.01) more likely than in women to achieve mRS 0-2. Women with right hemispheric strokes were 0.72 times (95% CI 0.54-0.92) less likely to reach mRS 0-2 than women with left hemispheric strokes. Conversely, men with right hemispheric strokes were 1.35 times (95% CI 1.06-1.70) more likely to achieve mRS 0-2 than men with left hemispheric strokes.
  
  
  CONCLUSIONS
  This study suggests that outcomes are different in both sexes after IVT when different hemispheres are affected. Further consideration of this hypothesis in clinical trials might help in guiding individualized, injury-specific treatment approaches for acute ischemic stroke.
authors.affiliation: Department of Neurology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Hametner
authors.forename: Peter
authors.initials: P
authors.lastname: Ringleb
authors.forename: Lars
authors.initials: L
authors.lastname: Kellert
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D054022:Cerebrum / Q000098:blood supply*; D016208:Databases, Factual; D004185:Disability Evaluation; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D007839:Functional Laterality; D054624:Health Status Disparities; D006801:Humans; D007262:Infusions, Intravenous; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D020521:Stroke / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D015912:Thrombolytic Therapy / Q000009:adverse effects; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D005343:Fibrinolytic Agents