Intravenous Thrombolysis in Patients With White Matter Hyperintensities in the WAKE-UP Trial.

BACKGROUND

White matter hyperintensities of presumed vascular origin (WMH) are the most prominent imaging feature of cerebral small vessel disease (cSVD). Previous studies suggest a link between cSVD burden and intracerebral hemorrhage and worse functional outcome after thrombolysis in acute ischemic stroke. We aimed to determine the impact of WMH burden on efficacy and safety of thrombolysis in the MRI-based randomized controlled WAKE-UP trial of intravenous alteplase in unknown onset stroke.

METHODS

The design of this post hoc study was an observational cohort design of a secondary analysis of a randomized trial. WMH volume was quantified on baseline fluid-attenuated inversion recovery images of patients randomized to either alteplase or placebo in the WAKE-UP trial. Excellent outcome was defined as score of 0-1 on the modified Rankin Scale after 90 days. Hemorrhagic transformation was assessed on follow-up imaging 24-36 hours after randomization. Treatment effect and safety were analyzed by fitting multivariable logistic regression models.

RESULTS

Quality of scans was sufficient in 441 of 503 randomized patients to delineate WMH. Median age was 68 years, 151 patients were female, and 222 patients were assigned to receive alteplase. Median WMH volume was 11.4 mL. Independent from treatment, WMH burden was statistically significantly associated with worse functional outcome (odds ratio, 0.72 [95% CI, 0.57-0.92]), but not with higher chances of any hemorrhagic transformation (odds ratio, 0.78 [95% CI, 0.60-1.01]). There was no interaction of WMH burden and treatment group for the likelihood of excellent outcome (

CONCLUSIONS

Although WMH burden is associated with worse functional outcome, there is no association with treatment effect or safety of intravenous thrombolysis in patients with ischemic stroke of unknown onset.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT01525290.