Pharmacotherapy for the secondary prevention of stroke

Abstract

Stroke recurrence continues to be the major risk for stroke survivors. Risk factor control and antithrombotic medication are two major strategies for patients with a prior stroke or transient ischaemic attack (TIA) to prevent stroke recurrence. Hypertension, dyslipidaemia and diabetes mellitus are risk factors that are modifiable by pharmacotherapy, as well as by lifestyle modification. Antihypertensive treatment is recommended for secondary stroke prevention for both hypertensive and normotensive patients. HMG-CoA reductase inhibitor (statin) therapy to obtain an intensive lipid-lowering effect is also highly recommended. A recent trial indicated that treatment with pioglitazone is effective for patients with type 2 diabetes. However, the evidence for risk factor control is relatively new, and further studies are needed for better evidence-based prevention. For patients with noncardioembolic ischaemic stroke or TIA, antiplatelet therapy rather than anticoagulation is recommended to reduce the risk of recurrent stroke and other cardiovascular events. Aspirin was the first antiplatelet agent to have established evidence for secondary stroke prevention. Currently, aspirin monotherapy, the combination of aspirin and extended-release dipyridamole, and clopidogrel monotherapy are recommended as the major choices. The combination of aspirin and clopidogrel is not routinely recommended. Adjusted-dose warfarin with a target international normalized ratio range between 2.0 and 3.0 is recommended after an ischaemic stroke or TIA associated with nonvalvular atrial fibrillation. Bleeding complications are a critical problem with antithrombotic therapy. Warfarin, as well as antiplatelet therapy, increases the incidence of bleeding and worsens the severity of the bleeding events. Choosing antithrombotic agents and their intensity (dosage) appropriate to the stroke mechanism and the patient's condition are essential for secondary stroke prevention.