Wake-up Stroke and Stroke within the Therapeutic Window for Thrombolysis Have Similar Clinical Severity, Imaging Characteristics, and Outcome

Abstract

Background: Wake-up stroke (WUS) represents 25% of all ischemic strokes. There is conflicting evidence concerning clinical severity, imaging characteristics, and outcome when WUS is compared with stroke of known time of onset. Our aim was to compare WUS patients with patients with ischemic stroke within the therapeutic window (STW) for thrombolysis. Methods: This is a retrospective hospitalbased study of all consecutive patients hospitalized for acute ischemic stroke during 2013. Patients with STW, WUS, and WUS with computed tomography (CT) at 3 hours or less after awakening (WUS≤3h) were selected for the study. The methods used include a review of clinical records, an independent quantification of early signs of ischemia on admission CT scan, and determination of functional outcome on follow-up. Results: Of 554 patients evaluated, 190 had STW, 113 had WUS (20.4%), and 25 had WUS≤3h. Among all WUS patients, 33.6% did not have any other formal contraindication for thrombolysis besides undetermined time of onset. WUS patients had demographic characteristics, vascular risk factors, and clinical severity similar to STW patients. Mild or absent early signs of ischemia on admission CT in WUS≤3h patients were similar to those in STW patients when adjusted for clinical severity (odds ratio [OR] = .50, 95% confidence interval [CI]=.17-1.47). Favorable prognosis in WUS≤3h was similar to STW when adjusted for age, clinical severity, and thrombolysis (OR = .53, 95% CI=.09-3.14). Conclusions: This study strengthens the evidence that clinical and early imaging characteristics of WUS patients are similar to those of patients with stroke who are eligible for thrombolysis based on the time window criteria, and patients with WUS do not have a worse short outcome. Key Words: Wake-up stroke-ischemic stroke-computed tomography-stroke outcome.

Intravenous thrombolysis in wake‐up stroke: real‐world data from the Austrian Stroke Unit Registry

“…Further, our results suggest that there are no differences in baseline characteristics between WUS and KOS. These findings are in line with previous studies and underline the concept that patients with WUS are comparable candidates for reperfusion strategies . The frequency of IV tPA‐treated WUS was found to be 7.2%, which increased continuously over the whole study period.…”

Wake-Up Stroke versus Stroke with Known Onset Time: Clinical and Multimodality CT Imaging Characteristics

“…In another study, WUS patients were not at increased odds for unfavorable functionality or in-hospital mortality after adjustment for age, NIHSS score on admission, and IV-rtPA use [5]. In one study comparing patients imaged within 4.5 h after symptom onset in WUS patients, WUS patients had lower pc-ASPECTS scores comparable to our results [22]. Studies that compared WUS patients to patients with a known time to symptom onset of < 3 h showed no difference in ischemic changes on NCCT findings [9, 23].…”

“…In a previous study, no significant differences were shown in clinical features between patients with a WUS and patients with a known onset time of their stroke [5, 6, 9, 21, 22]. In another study, WUS patients were not at increased odds for unfavorable functionality or in-hospital mortality after adjustment for age, NIHSS score on admission, and IV-rtPA use [5].…”

Endovascular Thrombectomy in Wake-Up Stroke and Stroke with Unknown Symptom Onset

“…31 Indeed, it was shown that clinical and imaging characteristics in WUS and stroke eligible for intravenous thrombolysis seem to be comparable, whereas DUS-as in our cohort-tends to have a worse prognosis. 13,32,33 We did not observe significant differences in baseline characteristics. Longer imaging-to-groin times in WUS and DUS can be explained by a higher percentage of MR imaging scans and might indicate a careful patient selection.…”