The treatment effect across ASPECTS in acute ischemic stroke: Analysis from the AcT Trial.

ABSTRACT

BACKGROUND: Early ischemic changes on baseline imaging are commonly evaluated for acute stroke decision-making and prognostication. AIMS: We assess the association of early ischemic changes on clinical outcomes and whether it differs between intravenous tenecteplase versus Alteplase. METHODS: Data are from the phase 3, Alteplase compared to Tenecteplase (AcT) trial. Subjects with anterior circulation stroke were included. Early ischemic changes were assessed using the Alberta Stroke Program Early CT score (ASPECTS). Efficacy outcomes included modified Rankin scale (mRS) 0-1, mRS 0-2, and ordinal mRS at 90 days. Safety outcomes included 24-hour symptomatic intracerebral hemorrhage (sICH), any hemorrhage on follow-up scan, and 90-day mortality rate. Mixed effects logistic regression was used to assess the association of ASPECTS [continuous and categorical (0-4 vs. 5-7 vs. 8-10)] with outcomes and if these associations were modified by thrombolytic type after adjusting for age, sex, and baseline stroke severity. RESULTS: Of the 1577 patients in the trial, 901 patients (56.3%) (median age 75 years [IQR 65-84], 50.8% females, median NIHSS 14 [IQR 17-19]) with anterior circulation stroke were included. mRS 0-1 at 90d was achieved in 1/14 (0.3%), 43/160 (14.7%) and 252/726 (85.1%) in the ASPECTS 0-4, 5-7 and 8-10 groups respectively. Every 1-point decrease in ASPECTS was associated with 2.7% and 1.9% decrease in chances of mRS 0-1 and mRS 0-2 at 90 days, respectively, and 1.9% chances of increase in mortality at 90 days. Subgroup analysis in EVT treated population showed similar results. Thrombolytic type did not modify this association between ASPECTS and 90-day mRS 0-1 (P interaction 0.75). There was no significant interaction by thrombolytic type with any other outcome. CONCLUSIONS: Similar to prior studies, we found that every one-point decrease in ASPECTS was associated with poorer clinical and safety outcomes. This effect did not differ between alteplase and tenecteplase.