Antiplatelet or anticoagulant treatment if further TIA or ischaemic stroke whilst taking aspirin

If a person has a further ischaemic stroke or TIA whilst taking aspirin, then s/he should be fully investigated for potential causes of these events. There is no agreement on the best preventive antiplatelet agent for these patients but options include (1):

• adding m/r dipyridamole to aspirin
• switching to clopidogrel
• adding clopidogrel to aspirin
• switching to warfarin

Notes:

• antiplatelet therapy is on of several effective measures that reduce the risk of a further event after a TIA or stroke. However other areas such as blood pressure, cholesterol, diabetes and smoking should also be addressed
• aspirin plus dipyridamole is recommended as the initial treatment following an initial episode of cerebral ischaemia
  • the ESPRIT results, combined with the results of previous trials, provide sufficient evidence to prefer the combination regimen of aspirin plus dipyridamole over aspirin alone as antithrombotic therapy after cerebral ischaemia of arterial origin (2)
  • the combination of modified-release (MR) dipyridamole and aspirin is recommended for people who have had an ischaemic stroke or a transient ischaemic attack (TIA) for a period of 2 years from the most recent event (3)
• the ProFESS trial compared the efficacy of 25 mg aspirin (ASA) and 200 mg extended-release dipyridamole (ER-DP) twice a day versus 75 mg clopidogrel once a day
  • in patients with ischaemic stroke, both regimes resulted in similar rates of recurrent stroke

Reference:

• 1. MeReC Bulletin (2003), 14 (2), 5-8.
• 2. ESPRIT study group. Aspirin plus dipyridamole versus aspirin alone after cerebral ischaemia of arterial origin (ESPRIT): randomised controlled trial. Lancet. 2006 May 20;367(9523):1665-73
• 3. NICE Guidance (May 2005) - Clopidogrel and modified-release dipyridamole in the prevention of occlusive vascular events
• 4. Diener HC et al. Effects of aspirin plus extended-release dipyridamole versus clopidogrel and telmisartan on disability and cognitive function after recurrent stroke in patients with ischaemic stroke in the Prevention Regimen for Effectively Avoiding Second Strokes (PRoFESS) trial: a double-blind, active and placebo-controlled study. Lancet Neurol. 2008 Oct;7(10):875-84.