Clinical and Imaging Data at 5 Days as a Surrogate for 90-Day Outcome in Ischemic Stroke

Abstract

Background and Purpose— A simple, easily measured surrogate outcome measure for use in early treatment trials for acute ischemic stroke therapies would be highly valued. We hypothesized that day-5 NIH stroke scale score (NIHSS) and day-5 diffusion weighted imaging (DWI) volume would predict clinical outcome better than either alone and could be considered as a possible surrogate outcome in early phase acute stroke trials. Methods— The prospective Acute Stroke Accurate Prediction (ASAP) trial included a prespecified subgroup evaluated for early outcome. Logistic regression analysis was used to assess the prediction of modified Rankin (mRankin) of 0 or 1. Results— A total of 204 subjects completed the substudy, and 116 (57%) had excellent outcome at 3 months. The area under the ROC curve (AUC) for day-5 NIHSS predicting 3-month excellent outcome was 0.84; for DWI volume predicting outcome was 0.76, and for the multivariable model combining both was 0.84. Conclusions— The results of the early outcome substud...