Abstract WMP96: The Iscore Predicts Clinical Response To Thrombolysis: Results From VISTA
Background: The iScore is a validated tool developed to estimate the risk of death and functional outcomes early after an acute ischemic stroke. It includes demographics, stroke severity and subtype, comorbidities, pre-stroke status, and glucose on admission.
Objective: To determine the ability of the iScore to predict the clinical response after iv thrombolysis (tPA) in the Virtual International Stroke Trials Archive (VISTA).
Methods: We applied the iScore (www.sorcan.ca/iscore) to patients with an acute ischemic stroke within the VISTA collaboration. We explored the association between the iScore (as continuous and binary [<200 and ≥200] measures) and the outcomes of interest.
Outcome Measures: The primary outcome was death or disability at 90 days defined as a modified Rankin scale (mRS) 4-to-6. Secondary outcomes included death at 90 days and favorable outcome (mRS 0-2).
Results: Among 7140 patients with an acute ischemic stroke, 2732 (38.5%) received tPA and 712 (10%) had an iScore ≥200. Patients with higher iScore had worse clinical outcomes (p<0.0001 for all outcomes; c-statistics 0.777 for mRS0-6 and 0.748 for death at 90 days). Overall, an iScore ≥200 was associated with nine fold higher risk of death or disability at 90 days (OR 9.41, 95%CI 7.00-12.6). Similar trends were observed for secondary outcomes (Figure). tPA administration in stroke patients with an iScore≥200 was associated with a lower risk of death or disability at 90 days (OR 0.48; 95%CI 0.32-0.72). There was a direct interaction between the iScore and tPA for both death or disability and death alone at 90 days (p-value for the interaction <0.001).
Conclusion: The iScore is a useful tool that can be used to estimate clinical outcomes after tPA. Although outcomes were poorer for the high-risk group (iScore≥200), the benefits of tPA in this group were greater than for low-risk patients. Figure
- © 2012 by American Heart Association, Inc.