Individualized risk prediction of major bleeding in secondary stroke prevention

In most patients diagnosed with a TIA or ischemic stroke, secondary stroke prevention relies on antiplatelet therapy unless anticoagulation is indicated. Aspirin has the largest evidence base and reduces the risk of early recurrent ischemic stroke without a major risk of early hemorrhagic complications.1 Because antiplatelet therapy typically continues for many years, clinicians and patients need an estimation of the annual bleeding risk to accurately assess future risk. In a meta-analysis of 25 randomized trials of antiplatelet therapy in primary or secondary prevention of cardiovascular disease, aspirin increased the absolute annual risk of major bleeding by 0.13% (number needed to harm 769).2 The reduction in vaso-occlusive events after ischemic stroke seems to outweigh the increased risk of bleeding with antiplatelet therapy. However, might we identify patients more likely harmed than benefited by antiplatelet therapy? Risk models for bleeding risk could direct physicians in deciding to withhold antiplatelet therapy for some patients, but the poor accuracy of available models has hampered implementation in daily clinical practice.3 Dr. Lemmens is a Senior Clinical Investigator of FWO Flanders.