Sex differences in severity of stroke in the INSTRUCT Study: a meta-analysis of individual participant data
Methods and Results: We pooled individual participant data with National Institutes of Health Stroke Scale assessment (N=6343) from 8 population-based stroke incidence studies (1996-2014), forming part of INSTRUCT (International Stroke Outcomes Study). Information on sociodemographics, stroke-related clinical factors, comorbidities, and pre-stroke function were obtained. Within each study, relative risk regression using log-binominal modeling was used to estimate the female:male relative risk ( RR ) of more severe stroke (National Institutes of Health Stroke Scale>7) stratified by stroke type (ischemic stroke and intracerebral hemorrhage). Study-specific unadjusted and adjusted RR s, controlling for confounding variables, were pooled using random-effects meta-analysis. National Institutes of Health Stroke Scale data were recorded in 5326 (96%) of 5570 cases with ischemic stroke and 773 (90%) of 855 participants with intracerebral hemorrhage. The pooled unadjusted female:male RR for severe ischemic stroke was 1.35 (95% CI 1.24-1.46). The sex difference in severity was attenuated after adjustment for age, pre-stroke dependency, and atrial fibrillation but remained statistically significant (pooled RRadjusted 1.20, 95% CI 1.10-1.30). There was no sex difference in severity for intracerebral hemorrhage ( RRcrude 1.08, 95% CI 0.97-1.21; RRadjusted 1.08, 95% CI 0.96-1.20).
Conclusions: Although women presented with more severe ischemic stroke than men, much although not all of the difference was explained by pre-stroke factors. Sex differences could potentially be ameliorated by strategies to improve pre-stroke health in the elderly, the majority of whom are women. Further research on the potential biological origin of sex differences in stroke severity may also be warranted.
History
Publication title
Journal of the American Heart AssociationVolume
8Article number
e010235Number
e010235Pagination
1-12ISSN
2047-9980Department/School
Menzies Institute for Medical ResearchPublisher
Wiley-Blackwell Publishing, Inc.Place of publication
United StatesRights statement
Copyright 2018 The Authors. Licensed under Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) https://creativecommons.org/licenses/by-nc/4.0/Repository Status
- Open