Neurological Outcomes in Patients With Ischemic Stroke Receiving Enoxaparin or Heparin for Venous Thromboembolism Prophylaxis

Abstract

Background and Purpose— The Prevention of VTE after Acute Ischemic Stroke with LMWH (PREVAIL) study demonstrated that enoxaparin was superior to unfractionated heparin (UFH) in preventing venous thromboembolism in patients with ischemic stroke and was associated with a small but statistically significant increase in extracranial hemorrhage rates. In this PREVAIL subanalysis, we evaluate the long-term neurological outcomes associated with the use of enoxaparin compared with UFH. We also determine predictors of stroke progression. Methods— Acute ischemic stroke patients aged ≥18 years, who could not walk unassisted, were randomized to receive enoxaparin (40 mg once daily) or UFH (5000 U every 12 hours) for 10 days. Patients were stratified according to baseline stroke severity using the National Institutes of Health Stroke Scale score. End points for this analysis included stroke progression (≥4-point increase in National Institutes of Health Stroke Scale score), neurological outcomes up to 3 months postrandomization (assessed using National Institutes of Health Stroke Scale score and modified Rankin Scale score), and incidence of intracranial hemorrhage. Results— Stroke progression occurred in 45 of 877 (5.1%) patients in the enoxaparin group and 42 of 872 (4.8%) of those receiving UFH. Similar improvements in National Institutes of Health Stroke Scale and modified Rankin Scale scores were observed in both groups over the 90-day follow-up period. Incidence of intracranial hemorrhage was comparable between groups (20 of 877 [2.3%] and 22 of 872 [2.5%] in enoxaparin and UFH groups, respectively). Baseline National Institutes of Health Stroke Scale score, hyperlipidemia, and Hispanic ethnicity were independent predictors of stroke progression. Conclusions— The clinical benefits associated with use of enoxaparin for venous thromboembolism prophylaxis in patients with acute ischemic stroke are not associated with poorer long-term neurological outcomes or increased rates of symptomatic intracranial hemorrhage compared with UFH.