Interní Med. 2009; 11(9): 384-388

Aspirin resistance - recent concepts and guidelines for practice

MUDr. Jana Hirmerová

II. interní klinika LF UK a FN, Plzeň

In spite of proven efficacy in the prevention of atherothrombotic vascular events, aspirin is not able to prevent thrombosis in all patients.

“Aspirin resistance” is not a precise descriptor, the term is used in clinical sense (as a failure to prevent a thrombotic complication), as

well as in laboratory sense (impossibility to prove the effect of aspirin by some laboratory assay). Diagnostic methods for aspirin resistance

are poorly standardized, there are number of assays that do not correlate well with each other and only some of them have been

tested for clinical relevance. Because of heterogeneous methodology, the prevalence of aspirin resistance is reported in a wide range;

according to recent metaanalysis the mean prevalence is 24 %. Numerous mechanisms of aspirin resistance have been suggested but in

the real world the most often mechanism is probably non-compliance and interaction with non-steroidal antiiflammatory drugs. Many

clinical studies have proven the association of aspirin resistance with the increased risk of cardiovascular events. However, there is no

evidence-based management able to reduce this risk; higher aspirin dose or its replacement or combination with other antiplatelet

agent should be considered. At present, routine evaluation of aspirin resistance is not recommended.

Keywords: aspirin resistance, diagnostics, prevalence, cardiovascular event.

Published: October 1, 2009  Show citation