Afsaneh Forood - Assistant Professor, Department of Cardiology AND Physiology Research Center, Kerman University of Medical Sciences, Kerman, Iran
Reza Malekpour-Afshar - Associate Professor, Neuroscience Research Center, Kerman University of Medical Sciences, Kerman, Iran
Jamshid Sarnevesht - Resident, Department of Cardiology, School of Medicine, Kerman University of Medical Sciences, Kerman, Iran

Background: The rate of cardiovascular diseases in developing countries is approximately ۶۰% and it is still has an increasing trend. The clinical effectiveness of aspirin in preventing cardiovascular events has been well proven. Although aspirin is an effective and inexpensive drug, its consumption is not equally beneficial for all patients. Many factors can be affective on the efficacy of antiplatelet drugs such as aspirin. Methods: This study was carried out on ۲۶۰ patients who had stable angina pectoris and coronary artery disease was approved by coronary angiography. Based on opium addiction, the patients were divided into two groups. Opium addiction was diagnosed base on Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM IV) criteria. The mid stream morning urinary sample were collected for measuring the urinary ۱۱-dehydroxy thromboxane B۲ level (UTXB۲). Urinary level of UTXB۲ was considered as an aspirin resistance index. Findings: The mean age of patients was ۵۷.۳ ± ۸.۹; and ۴۴.۶% of them were females. The aspirin resistance rate was ۴۱.۵%. Significant difference in aspirin resistance was observed between the opium addicts and non-addicts. (۵۱.۵% vs. ۳۱.۵%) (P = ۰.۰۰۱). The effects of confounding variables such as diabetes, hypertension, and hyperlipidemia were eliminated by regression logistic multivariable analysis. Conclusion: The prevalence of aspirin resistance in patients with stable angina pectoris was ۴۱.۵%. The prevalence of aspirin resistance in patients with stable angina pectoris who had opium addiction was significantly higher them non-addicts.

opium addiction, Aspirin resistance, Stable angina pectoris, Coronary Angiography