title: Aspirin resistance in patients with acute coronary events: risk factors and prevalence as determined by whole blood multiple electrode aggregometry.
abstract: OBJECTIVE
  To determine the prevalence of aspirin resistance and associated risk factors based on biochemical parameters using whole blood multiple electrode aggregometry.
  
  
  METHODS
  The study was conducted at the outpatients cardiology clinic of the Universiti Kebangsaan Malaysia Medical Centre (UKMMC) from August 2011 to February 2012. Subjects on aspirin therapy were divided into two groups; first-ever coronary event and recurrent coronary event. Aspirin resistance was measured by a Multiplate(®) platelet analyser.
  
  
  RESULTS
  A total of 74 patients (63 male, 11 female), with a mean age of 57.93 ± 74.1years were enrolled in the study. The patients were divided into two groups -first-ever coronary event group (n=52) and recurrent coronary event group (n=22). Aspirin resistance was observed in 12 out of 74 (16%) of the study patients, which consisted of 11 patients from the first-ever coronary event group and one patient from the recurrent coronary event group. There were significant correlations between aspirin resistance and age (r = -0.627; p = 0.029), total cholesterol (r = 0.608; p = 0.036) and LDL (r = 0.694; p = 0.012). LDL was the main predictor for area under the curve (AUC) for aspirin resistance. However, there was no association between aspirin resistance and cardiovascular events in both groups in this study.
  
  
  CONCLUSIONS
  Aspirin resistance was observed in 16% of the study population. LDL was the major predictor of aspirin resistance. No association was found in the study between aspirin resistance with recurrent coronary events.
authors.affiliation: O. Ibrahim, Department of Medicine, University Kebangsaan Malaysia Medical Centre, Cheras 56000, Kuala Lumpur, Malaysia.
authors.forename: O
authors.initials: O
authors.lastname: Ibrahim
authors.affiliation: O. Maskon, Department of Medicine, University Kebangsaan Malaysia Medical Centre, Cheras 56000, Kuala Lumpur, Malaysia.
authors.forename: O
authors.initials: O
authors.lastname: Maskon
authors.affiliation: Noor Darinah, Department of Medicine, University Kebangsaan Malaysia Medical Centre, Cheras 56000, Kuala Lumpur, Malaysia.
authors.forename: Noor
authors.initials: N
authors.lastname: Darinah
authors.affiliation: A A Raymond, Department of Medicine, University Kebangsaan Malaysia Medical Centre, Cheras 56000, Kuala Lumpur, Malaysia.
authors.forename: A A
authors.initials: AA
authors.lastname: Raymond
authors.affiliation: M.M. Rahman, Department of Medical Microbiology & Immunology.
authors.forename: M M
authors.initials: MM
authors.lastname: Rahman
keywords: Aspirin resistance; Multiplate® platelet analyser; aspirin responsiveness; first-ever coronary event; recurrent coronary event