Background: Atherosclerosis is the leading cause of mortality in the developed and some developing countries. Some people believe that opium abuse has beneficial effects for reducing blood lipids and atherosclerosis prevention. In this study, the effect of oral opium addiction on lipid profile and atherogenesis in normal and hypercholesterolemic rabbits was studied.

Methods: Thirty two male Newzeland White rabbits were used in this study. They were divided into four groups including control, hypercholesterolemic, addicted, and hypercholesterolemic addicted and were studied for three months. The blood samples were obtained and lipid profile was determined at the beginning of the study and at the end of every month thereafter. After 90 days aorta was removed to assess for lesion formation.

Results: The levels of cholesterol, triglyceride (TG), high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C), and atherogenic index (total cholesterol/HDL-C) in the hypercholesterolemic and hypercholesterolemic addicted rabbits were increased significantly (P<0.001). These increases in lipids and aorta lesion areas were higher in hypercholesterolemic addicted group than hypercholesterolemic group.

Conclusion: These findings suggest that oral opium abuse affects cholesterol metabolism and depending on the dietary condition can have an aggravating effect on atherosclerosis. The protective effect of morphine on cardiac disease is not probably through the modulation of lipid metabolism.