Can opium abuse be a risk factor for carotid stenosis in patients who are candidates for coronary artery bypass grafting?

Over the centuries, opium has been the most frequent substance abused in the Middle East. There are many controversial aspects about the effects of opioids on the atherosclerosis process, which is still unclear. All patients who were candidates for coronary artery bypass graft in Tehran Heart Center were registered and evaluated for risk factors such as diabetes mellitus, hypertension, smoking status and duration, opium abuse, involved coronary arteries and left main branch lesion > 50%, carotid stenosis > or = 70%. A total of 1,339 patients were enrolled in the study, of whom 400 (29.9%) were female and the other 939 (70.1%) male. Female patients were omitted from analysis due to the low numbers of female opium addicts. Our study revealed that in the addicted population, the risk of diabetes and hypertension was lower than in the non-addicted group (p < 0.05 for each variable) and fasting blood sugar tended to be less in addicted ones, but the number of involved coronary arteries, left main stenosis > 50% and extent of carotid stenosis was not significantly different between the two groups. Our investigations demonstrate that opium is not cardioprotective, as has been claimed by some previous studies, and does not even decelerate atherosclerosis of carotid arteries in opium-addicted patients, but more evidence is still needed to completely prove the case.