Abstract WMP53: Sex Differences n Long-term Mortality and Disability After Stroke: The International Stroke Outcomes Study
Introduction: It is uncertain why women suffer worse long-term outcomes after stroke than men. We examined sex differences in mortality and disability 1 and 5 years after stroke and identified factors contributing to these differences.
Methods: Individual patient data pooling study of incident strokes (ischemic and hemorrhagic) from 1987-2013 obtained from 12 population-based cohorts from Australasia, Europe, South America and the Caribbean. Data on socio-demographics, stroke-related factors and pre-stroke health were obtained for each patient and harmonized between studies. Poisson modelling estimated the mortality rate ratio (MRR) for women compared to men at 1 year (12 studies) and 5 years (7 studies) post-stroke. Log binomial regression estimated the relative risk (RR) of poor outcome (modified Rankin scale>2 or Barthel Index <20) for women compared to men at 1 year (9 studies) and 5 years (6 studies) after stroke. Multivariable models were adjusted for potential confounders including age, pre-stroke dependency, stroke severity and comorbidities.
Results: A total of 16557 first-ever-stroke patients with follow-up data to 1 year and 12,839 with follow-up to 5 years were included. The pooled crude mortality was greater in women than men at 1-year (MRR 1.37 95% CI 1.27-1.48) and 5 years (MRR 1.25 95% CI 1.13-1.39). However, these sex differences were reversed after adjustment for confounders at both 1 year (MRR 0.94 95% CI 0.82-1.06) and 5-years post stroke (MRR 0.74 95% CI 0.66-0.84). Similarly, the pooled crude RR for disability after stroke was greater in women than men at 1-year (RR 1.28 95% CI 1.17-1.39 and 5-year (RR 1.32 95% CI 1.18-1.47), but these sex differences disappeared after adjustment at both 1 year (RR 1.08 95%CI 0.98-1.18) and 5-years post stroke (RR 1.08 95% CI 0.97-1.20). The key contributors to worse outcomes in women were greater age, pre-stroke dependency, severe strokes and atrial fibrillation (AF, mortality only) compared with men.
Conclusion: Worse outcomes in women were mostly due to age and potentially modifiable factors of stroke severity and AF providing potential targets to reduce the impact of stroke in women.
Author Disclosures: H.T.K. Phan: None. M.J. Reeves: None. L. Blizzard: None. A. Thrift: None. D. Cadilhac: None. E. Heeley: None. J. Sturm: None. S. Gall: None.
- © 2016 by American Heart Association, Inc.