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A Magnetic Resonance Imaging Protocol for Stroke Onset Time Estimation in Permanent Cerebral Ischemia
Published on: September 16, 2017
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Differences in wake-up and unknown onset stroke examined in a stroke registry
John M Reid1, Dingwei Dai, Bharath Cheripelli
1Department of Neurology, Aberdeen Royal Infirmary, Aberdeen, Scotland, UK.
Summary
Wake-up stroke (WUS) patients show similar outcomes to awake onset stroke (AOS) patients, while unknown onset stroke (UOS) patients have worse prognosis. UOS prevalence is increasing, indicating a need for further research into this stroke type.
Area of Science:
- Neurology
- Stroke Medicine
- Epidemiology
Background:
- Distinguishing between wake-up stroke (WUS) and awake onset stroke (AOS) is debated.
- Unknown onset stroke (UOS) is less frequently studied, despite its unclear symptom timing.
Purpose of the Study:
- To investigate the differences in stroke characteristics and patient outcomes among WUS, AOS, and UOS groups.
- To analyze demographic and clinical factors associated with each stroke onset type.
Main Methods:
- Retrospective analysis of a stroke registry database (Halifax Infirmary, 1999-2011).
- Inclusion of 3890 hospitalized stroke patients.
- Data collection on demographics, stroke characteristics, and functional status (modified Rankin score) at discharge and 6 months.
Main Results:
- UOS patients were older, more frequently female, and lived alone compared to AOS patients.
- UOS prevalence increased from 10% to 16% during the study period.
- UOS exhibited higher stroke severity, increased in-hospital mortality (23% vs. 16%), and poorer 6-month functional outcomes (26% vs. 46% with mRS < 3) compared to AOS.
- WUS showed lower rates of intracerebral hemorrhage (ICH) but similar stroke severity and outcomes to AOS.
Conclusions:
- Wake-up stroke (WUS) patients have comparable outcomes to awake onset stroke (AOS) patients, with fewer intracerebral hemorrhages.
- Unknown onset stroke (UOS) prevalence is rising, characterized by increased stroke severity and a worse prognosis.
- Further research is warranted to understand and manage UOS effectively.
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