Abstract WP186: The Burden of White Matter Hyperintensities on Function Outcomes in Patients Treated for Acute Ischemic Stroke: A Post-Hoc Analysis of the IMS-III Trial

Abstract

Objective: This study is a post-hoc analysis of the Interventional Management of Stroke (IMS) III trial investigating the burden of white matter hyperintensities (WMH), using the van Swieten Scale (VSS), on functional outcomes for acute ischemic stroke (AIS) patients treated with either intravenous thrombolysis (IVT) or IVT with mechanical thrombectomy (MT). Background: WMH are a well-established marker for underlying cerebral microvascular disease. VSS quantifies the disease burden from zero to four with higher numbers signifying more advanced disease. A higher burden of WMH is associated with poor functional outcomes after IVT. However, early studies regarding WMH and outcomes after MT have been conflicting. Methods: We included IMS-III trial patients in either treatment arm whose VSS was graded on initial brain CT and 90-day function outcomes were not missing. The primary study outcome was a 90-days modified Rankin Scale of 0-2, termed good outcome. Results: There was a total of 656 patients enrolled in the trial and 618 patients were included in this analysis. The VSS grades of WMH range from 0-4 and included 476 (77.02%), 56 (9.06%), 38 (6.15%), 24 (3.88%), and 24 (3.88%) patients, respectively. Overall, higher VSS grade was associated with a lower probability of achieving a good functional outcome, even after adjustments (Figure 1). Of the 142 patients with any degree of WMH, only 22.5% had a good functional outcome compared to 46.6% of 476 patients without WMH (Table 1). Conclusions: Patients enrolled in the IMS-III trial with any burden of WMH on brain CT had a statistically significant lower odds of a good functional outcome compared to patients without WMH.