Prior clopidogrel use and outcome of acute coronary syndrome

Background Prior aspirin use has been associated with poorer outcome in acute coronary syndrome, and forms part of the TIMI Risk Score. It is not known if prior use of clopidogrel is associated with similar risk. Aim To assess if prior clopidogrel use is associated with higher risk in acute coronary syndrome. Participants Participants were 869 consecutive admissions to a Scottish district general hospital with suspected acute coronary syndrome. Methods Incidence of death, recurrent myocardial infarction or urgent percutaneous intervention at 2 weeks was recorded. Odds ratios for sub-groups on clopidogrel, aspirin or neither were calculated. Results Odds ratios were: clopidogrel 1.46 (95% ci 0.62–3.33), aspirin 1.09 (95% ci 0.64–1.85), neither 0.91 (95% ci 0.53–1.54). Conclusion No definite association was shown between clopidogrel use and outcome but there was a trend towards increased risk of major acute coronary events.