No Overall Benefit of Early Anticoagulant Therapy for Ischemic Stroke

In a Cochrane Review update, researchers sought to assess the effectiveness and safety of early anticoagulation for people with acute presumed or confirmed ischemic stroke.

Early use of anticoagulants has no overall beneficial effect for patients with acute ischemic stroke, as an update of a Cochrane Review published in Cochrane Database of Systematic Reviews showed reduced risk for recurrent stroke, deep vein thrombosis, and pulmonary embolism, but increased bleeding risk.

While treatment with anticoagulants may reduce the risk for recurrent stroke, bleeding risk should also be taken into account. The current update of a Cochrane Review first published in 1995 and last updated in 2015, aimed at determining the effectiveness and safety of anticoagulation treatment within the first 14 days of acute ischemic stroke onset.

A search of the Cochrane Stroke Group Trials Register, the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE, was conducted and identified 4 new relevant studies published since the last version of this review.

The updated review included 28 trials involving 24,025 patients (aged 28 to 92 years) with ischemic stroke, including 2 trials that enrolled patients within 12 hours of stroke onset, 4 that included patients within 24 hours of stroke onset, 11 with participants within 48 hours of stroke onset, and 11 with participants within 14 days of stroke onset.

Anticoagulants tested were standard unfractionated heparin, low-molecular-weight heparins, heparinoids, oral anticoagulants, and thrombin inhibitors.

Data on death and long-term disability from 12 trials indicated early anticoagulation treatment was not associated with a significant reduction in the risk for death or dependence at the end of follow-up (odds ratio [OR], 0.98; 95% CI, 0.92-1.03). Data from 22 trials showed no impact of early anticoagulation on the risk for death from all causes (OR, 0.99; 95% CI, 0.90-1.09) during the treatment period.

While the risk for recurrent ischemic stroke (OR, 0.75; 95% CI, 0.65-0.88) and symptomatic pulmonary emboli (OR, 0.60; 95% CI, 0.44-0.81) was reduced with early use of anticoagulants, treatment was also associated with increased risk for symptomatic intracranial (OR, 2.47; 95% CI, 1.90-3.21) and extracranial (OR, 2.99; 95% CI, 2.24-3.99) hemorrhage.

“This review did not provide any evidence to suggest that early use of anticoagulants is  beneficial overall for people with stroke caused by blood clots. More research is needed to find out if there are ways to select people with stroke who will benefit most from anticoagulants without suffering the bleeding complications,” concluded the researchers.


Wang X, Ouyang M, Yang J, Song L, et al. Anticoagulants for acute ischaemic stroke. Cochrane Database Syst Rev. Published online October 22, 2021. doi: 10.1002/14651858.CD000024.pub5

This article originally appeared on Neurology Advisor