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Stroke outcome in clinical trial patients deriving from different countries
Myzoon Ali1, Sari Atula, Philip M W Bath
1Division of Cardiovascular and Medical Sciences, University Department of Medicine & Therapeutics, Gardiner Institute, 44 Church St, Glasgow G11 6NT, UK. myzoonali@clinmed.gla.ac.uk
Stroke
|October 18, 2008
Summary
Geographical location impacts stroke severity and survival rates, with variations not fully explained by patient factors. Stroke severity increased in recent years without improved outcomes.
Area of Science:
- Neurology
- Epidemiology
- Clinical Trials
Background:
- Stroke incidence and outcomes exhibit significant geographical disparities.
- Previous analyses did not fully account for case mix when examining these variations.
Purpose of the Study:
- To investigate if geographical differences in stroke severity, risk factors, mortality, and outcomes persist after adjusting for case mix.
- To analyze stroke patient data from the Virtual International Stroke Trials Archive (VISTA).
Main Methods:
- Logistic regression was used to analyze mild index stroke, functional, and neurological outcomes, controlling for age, medical history, and year of recruitment.
- Cox proportional hazards model was employed to examine mortality across geographical regions, adjusting for age, stroke severity, medical history, and recruitment year.
- Data from 3284 patients in the Virtual International Stroke Trials Archive (VISTA) were analyzed.
Main Results:
- Patients in the USA and Canada presented with the most severe index strokes.
- Austria and Switzerland showed the best 90-day functional and neurological outcomes, while Germany had the worst.
- Patients in several European countries (Austria, Switzerland, Belgium, Netherlands, Finland, Germany, Greece, Israel, Spain, Portugal) had better survival rates than those in the USA and Canada.
- Stroke severity increased in trials after 1998, with no significant improvement in outcomes compared to earlier trials.
Conclusions:
- Regional variations in stroke severity, outcome, and mortality exist and are not entirely explained by case mix.
- Increased stroke severity in recent trials (post-1998) has not led to improved patient outcomes.
- Geographical factors play a significant role in stroke presentation and prognosis.
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