[Aspirin resistance 2003: a review of the literature]

Despite the development of new molecules, aspirin remains a mainstay of the antiplatelet therapy, indispensable for the secondary prevention of cardiovascular events. The therapeutic used is based on the platelet aggregation inhibition induced by aspirin. The concept of aspirin resistance corresponds to a total or almost total absence of the platelet aggregation inhibition generally observed in vitro under aspirin. The frequency of this resistance depends on the platelet aggregation test used and the population studied. In a population with stable coronary disease treated in the long term with 160 to 325 mg of aspirin daily, 8 to 35% of patients are non-responders. Many hypothesis on the mechanisms of the lack of antiplatelet effect of aspirin are under investigation. The clinical implication of the in vitro antiplatelet effect resistance of aspirin has recently been evidenced by a relative risk of cardiovascular events at two years at 3. This would support an individual adaptation of the anti-platelet therapy.