Resistance to low-dose aspirin therapy among patients with acute coronary syndrome in relation to associated risk factors
Journal of Clinical Pharmacy and Therapeutics,  Clinical Article

Salama MM et al. – There is inter–individual variability in response to the antiplatelet effect of standard doses of aspirin (150, 300 mg/day). The response to aspirin 300 mg/day is enhanced in resistant patients when compared to 150 mg/day. There was a significant association between aspirin resistance and atherothrombotic risk factors (diabetes, hyperlipidaemia and obesity).

Methods
  • The antiplatelet effect of 150 mg/day aspirin was studied prospectively in 50 consecutive patients with unstable angina or non–ST–segment elevation myocardial infarction.
  • Platelet aggregation was measured using optical platelet aggregometry and serum thromboxane B2 level.
  • Aspirin resistance was defined as collagen (1 μg/mL) and adenosine diphosphate (ADP) (5 μmol/L)–induced platelet aggregation of ≥40% when compared with control values.
  • Twenty healthy age– and sex–matched individuals were taken as a control group.
  • All patients were subjected to complete medical history (risk factors, medications), thorough clinical examination, ECG, coronary angiography and laboratory investigations including: complete haemogram, coagulation, kidney, liver and lipid profiles, fasting blood glucose and glycated haemoglobin (HbA1C).

Results
  • Eleven of 50 patients (22%) were found to be aspirin resistant.
  • A highly significant difference was found between the mean values of ADP, collagen–induced platelet aggregation percentage and thromboxane B2 level after aspirin 150 mg/day when compared with the corresponding mean values after aspirin 300 mg/day among the resistant patients (66 ± 7•01%, 62 ± 4•34% and 620 ± 64•58 pg/mL, respectively, vs. 26•87 ± 2•85%, 16•5 ± 3•8% and 77 ± 11•3 pg/mL) indicating enhanced response to aspirin after escalating the dose.
  • The presence of atherothrombotic risk factors (hypertension, smoking, family history of ischaemic heart disease and previous MI) were not statistically different between aspirin–resistant and aspirin–sensitive patients.
  • However, there was a highly significant difference between the aspirin sensitive and the resistant patients regarding the other risk factors (diabetes mellitus and dyslipidaemia) (P < 0•01).

Please login or register to follow this author.
► Click here to access PubMed, Publisher and related articles...
<< Previous Article | Next Article >>

Your Unread Messages in Internal Medicine

See All >> Messages include industry-sponsored communications and special communications from MDLinx

Most Popular Internal Medicine Articles

1 Effects of tea intake on blood pressure: A meta-analysis of 21 randomized controlled trials JACC - Journal of the American College of Cardiology, October 22, 2014    Clinical Article

2 Sweetened carbonated beverage consumption and cancer risk: Meta-analysis and review European Journal of Cancer Prevention, August 1, 2014    Evidence Based Medicine    Review Article

3 Acupuncture for chronic knee pain: a randomized clinical trial JAMA, October 1, 2014    Evidence Based Medicine    Clinical Article

4 Evaluation and treatment of older patients with hypercholesterolemia: A clinical review JAMA, October 20, 2014    Clinical Article

5 Lower versus higher hemoglobin threshold for transfusion in septic shock New England Journal of Medicine, October 7, 2014    Evidence Based Medicine    Clinical Article

6 Association between circulating 25-hydroxyvitamin D and incident type 2 diabetes: A mendelian randomisation study The Lancet Diabetes & Endocrinology, October 21, 2014    Clinical Article

7 Comparative effectiveness of pharmacologic treatments to prevent fractures: an updated systematic review Annals of Internal Medicine, September 29, 2014    Evidence Based Medicine    Review Article    Clinical Article

8 Long-term outcomes after stenting versus endarterectomy for treatment of symptomatic carotid stenosis: the International Carotid Stenting Study (ICSS) randomised trial The Lancet, October 16, 2014    Evidence Based Medicine    Clinical Article
Exclusive Author Commentary

9 Total expenditures per patient in hospital-owned and physician-owned physician organizations in California JAMA, October 24, 2014    Evidence Based Medicine    Clinical Article

10 Triglycerides and cardiovascular disease The Lancet, August 19, 2014    Evidence Based Medicine    Clinical Article

11 Nut consumption and the risk of coronary artery disease: A dose–response meta-analysis of 13 prospective studies Thrombosis Research, October 22, 2014    Clinical Article

12 Assessment of the potential for international dissemination of Ebola virus via commercial air travel during the 2014 west African outbreak The Lancet, October 23, 2014    Evidence Based Medicine    Clinical Article

13 Association of fat density with subclinical atherosclerosis Full Text Journal of the American Heart Association, September 19, 2014    Free full text

14 A randomized trial of epidural glucocorticoid injections for spinal stenosis New England Journal of Medicine, July 7, 2014    Evidence Based Medicine    Clinical Article

15 Ivabradine in stable coronary artery disease without clinical heart failure New England Journal of Medicine, September 2, 2014    Evidence Based Medicine    Clinical Article

16 Livebirth after uterus transplantation The Lancet, October 9, 2014    Evidence Based Medicine    Clinical Article

17 Exercises to improve function of the rheumatoid hand (SARAH): a randomised controlled trial The Lancet, October 14, 2014    Evidence Based Medicine    Clinical Article

18 Plasma triglycerides predict ten-years all-cause mortality in outpatients with type 2 diabetes mellitus: a longitudinal observational study Full Text Cardiovascular Diabetology, October 17, 2014    Free full text    Clinical Article

19 Readmissions after hospitalization for heart failure, acute myocardial infarction, or pneumonia among young and middle-aged adults: a retrospective observational cohort study Full Text PLoS Medicine, October 3, 2014    Free full text    Evidence Based Medicine    Clinical Article

20 The influence of whole grain products and red meat on intestinal microbiota composition in normal weight adults: A randomized crossover intervention trial PLOS ONE, October 22, 2014    Clinical Article

Indexed Journals in Internal Medicine: New England Journal of Medicine, The Lancet, Archives of Internal Medicinemore