Effectiveness of antiplatelet therapy in atherosclerotic disease: comparing the ASA low-response prevalence in CVD, CAD and PAD Saskia H. Meves • Thomas Hummel • Heinz G. Endres • Nora Maybo ¨ck • Andreas F. C. Kaiser • Kay D. Schro ¨der • Katja Ru ¨ diger • Ursula Overbeck • Achim Mumme • Andreas Mu ¨gge • Horst Neubauer Ó Springer Science+Business Media New York 2013 Abstract Although acetylsalicylic acid (ASA, aspirin) reduces the risk of ischemic events in patients with athero- sclerosis, a substantial number of incidents continue to occur. As only limited data exist we evaluated the antiplatelet effec- tiveness of ASA in patients with different manifestations of atherosclerosis as in cerebrovascular, coronary artery and peripheral arterial disease (CVD, CAD, PAD). For the evalu- ation of the antiplatelet effectiveness of ASA we used whole blood aggregometry (Chrono-log Model 590). The patients in the different subgroups received ASA 100, 200 or 500 mg daily. We analysed 737 consecutive patients: 47.5 % with CVD, 33.6 % with CAD, and 18.9 % with PAD. We identified 28.0 % of the CVD, 18.1 % of the CAD and 21.6 % of the PAD patients to be ASA low-responder (ALR). Comparing sub- groups treated with 100 mg ASA, 36.4 % were ALR in the CVD group as were 13.1 % of the CAD and 21.6 % of the PAD patients. Multivariate regression analysis revealed an odds ratio for being ALR of 4.50 (95 % confidence interval (CI) 1.70–11.9) when 100 mg and of 2.97 (95 % CI 1.58–5.60) when 200 mg ASA was taken compared to a dose of 500 mg. Despite the proven benefits of antiplatelet therapy in the sec- ondary prevention of atherosclerotic disease, current anti- platelet management is suboptimal as up to 36 % of patients failed to achieve an adequate platelet inhibitory effect. Our findings may explain, at least in part, the high rates of cardio- vascular events observed in the course of atherothrombotic disease and support the need to improve antiplatelet therapy. Keywords Impedance aggregometry Á Aspirin Á Platelet aggregation Á Stroke Á Coronary artery disease Á Peripheral artery disease Abbreviations AA Arachidonic acid ABI Ankle brachial index ACS Acute coronary syndrome AIS Acute ischaemic stroke ALR ASA low-responder ASA Acetylsalicylic acid (aspirin) CAD Coronary artery disease CRP C-reactive protein CVD Cerebrovascular disease HbA 1C Glycated hemoglobin A1c MI Myocardial infarction PAD Peripheral arterial occlusive disease PCI Percutaneous coronary intervention PPI Proton-pump inhibitor TIA Transient ischaemic attack Introduction Atherosclerotic disease is the leading cause of mortality and encompasses the clinical manifestations of acute ischemic Saskia H. Meves and Thomas Hummel contributed equally. S. H. Meves (&) Á K. D. Schro ¨der Á U. Overbeck Department of Neurology, St. Josef-Hospital, Ruhr University Bochum, Gudrunstraße 56, 44791 Bochum, Germany e-mail: saskia.m.meves@rub.de T. Hummel Á N. Maybo ¨ck Á K. Ru ¨diger Á A. Mumme Department of Vascular Surgery, St. Josef-Hospital, Ruhr University Bochum, 44791 Bochum, Germany H. G. Endres Department of Epidemiology, Ruhr University Bochum, 44791 Bochum, Germany A. F. C. Kaiser Á A. Mu ¨gge Á H. Neubauer Cardiovascular Center, St. Josef-Hospital, Ruhr University Bochum, 44791 Bochum, Germany 123 J Thromb Thrombolysis DOI 10.1007/s11239-013-0919-7