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For patients with acute coronary syndrome (ST-elevation or non-ST-elevation myocardial infarction, or unstable angina), resulting from occlusion of the coronary arteries, long-term antiplatelet therapy with low-dose acetylsalicylic acid (ASA) is recommended, with the addition of a P2Y 12-receptor inhibitor, such as clopidogrel, for the first 12 months of treatment. In patients previously hospitalized for a serious coronary event, combined antithrombotic therapy was associated with an increased risk of hemorrhagic stroke, whereas combined antiplatelet therapy was associated with an increased risk of UGIB.Non-use of ASA was rare in this population and use of ASA was not associated with a significantly increased risk of hemorrhagic stroke, UGIB, or LGIB.Ĭardiovascular disease remains the principal cause of mortality in Europe, being responsible for over 4 million deaths each year. An increased risk of LGIB (OR, 1.86 95 % CI, 1.34–2.57) was also observed in users of clopidogrel. Users of combined antithrombotic therapy (warfarin and antiplatelets) experienced an increased risk of hemorrhagic stroke (odds ratio, 6.36 95 % confidence interval, 1.34–30.16), whereas users of combined antiplatelet therapy (clopidogrel and ASA) experienced an increased risk of UGIB (OR, 2.42 95 % CI, 1.09–5.36). Non-users of ASA, who were mostly discontinuers, and current users of ASA had similar risks of hemorrhagic stroke, UGIB, and LGIB. UGIB and LGIB led to hospitalization in 73 and 23 % of patients, respectively. Incidences of hemorrhagic stroke, UGIB, and LGIB were 5.0, 11.9, and 25.5 events per 10,000 person-years, respectively, and increased with age. Risk factors for bleeding were determined in a nested case-control analysis. Patients were followed up until they reached an endpoint (hemorrhagic stroke, upper or lower gastrointestinal bleeding ), death or end of study ) or met an exclusion criterion.
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MethodsĪ UK primary care database was used to identify 27,707 patients aged 50 to 84 years, hospitalized for a serious coronary event during 2000 to 2007 and who were alive 30 days later (start date). This study estimated the incidence of bleeding events in patients previously hospitalized for a serious coronary event and determined the risks of bleeding associated with the use of acetylsalicylic acid (ASA) and/or clopidogrel. Bleeding events have been associated with the use of antiplatelet agents.