Abstract WP147: Influence of White Blood Cell Count on Outcome for Thrombolysis-Treated Acute Ischemic Stroke ENCHANTED Post HocAnalysis

Abstract

Background: Increased inflammatory reaction can aggravate brain injury after acute ischemic stroke, but the clinical effect of such response is not fully understood. The aim of this study was to determine associations of peripheral white blood cell (WBC) count on clinical outcome among participants of the ENCHANTED study. Methods: Data are from the Enhanced Control of Hypertension for < and > for > Thrombolysis Stroke Study (ENCHANTED), aninternational, multicenter, randomized controlled trial where patients with acute ischemic stroke were randomized to low-dose (0.6 mg/ kg) or standard-dose (0.9 mg/kg) IV alteplase.Blood samples were collected on admission < for < and > for > WBC count was measured at local laboratories. The primary outcome was death or disability, defined by scores 3–6 on the modified Rankin Scale at 90 days.Secondary outcomes included ordinal mRS shift,fatal intracerebral hemorrhage(ICH) by various standard criteria.Associations of baseline WBC count < for < and > for > outcomes were evaluated in logistic regression models. Results: There were 3179 participants with relevant data who were classified into quartiles of WBC counts (≤ 6.30, 6.31–7.82, 7.83–9.80, < for < and > for > ≥ 9.81х109/L, respectively).Increased WBC count was associated with younger age,elevated NIHSS scores, less antithrombotic used,elevated heart rate,elevated fever treated,stroke severity. Risks of death or major disability at 90 days increased progressively with higher WBC count: frequencies of 30.4%, 34.7%,39.1% < for < and > for > 44.8% for quartile groups, respectively (P <.0001 for trend). After adjustment for baseline clinical < for < and > for > imaging variables including age, sex, body temperature, systolic BP, heart rate, high NIHSS scores, < for < and > for > randomized treatment, the association between WBC count < for < and > for > primary outcome was still significant (P <.0001 for trend). Conclusions: Elevated WBC count on admission may be an independent prognostic predicator in patients with Acute Ischemic Stroke, but this requires further evaluation in a prospective cohort study.