Men who smoke are more likely to suffer from erectile dysfunction than nonsmokers, reports an international group of impotency experts in the November issue of the Journal of Urology.
Erectile dysfunction is the inability to achieve or maintain an erection suitable for sexual intercourse. It is estimated that over 30 million American men have some form of erectile dysfunction.
The research consortium, headed by Kevin T. McVary, associate professor of urology at Northwestern University Medical School, found strong parallels and shared risks among smoking, coronary artery disease, atherosclerosis and erectile dysfunction. Results of the group's review showed that smoking exacerbates the well-known negative effects of coronary artery disease and hypertension on a man's ability to achieve and maintain an erection.
In addition, prevalence of erectile dysfunction in former smokers was no different from that in men who had never smoked. McVary said that the vascular system in the penis is subject to the same degenerative diseases of blood vessels of the heart, kidneys, brain and major vascular systems. Smoking alters the ability of blood to coagulate and accelerates hypertension by promoting vasoconstriction and atherosclerosis. In turn, hypertension increases the need for drugs that induce or worsen erectile dysfunction.
The underlying cause of erectile dysfunction in smoking is poorly understood, but there is evidence that smoking may impair production of nitric oxide, the principal "chemical messenger" involved in penile erection, in the cells that line blood vessels. Nitric oxide also plays an important role in cardiovascular health and inhibition of apoptosis, or programmed cell death.
While the results of the group's study indicated that erectile dysfunction is linked to smoking and its related health risks, additional basic and clinical science studies will be required to determine the exact mechanism of the smoking effect and establish clinical practice guidelines for men with erectile dysfunction.
Scientists from the University of Washington School of Medicine, Seattle, McGill University Medical School, Montreal, and other members of the Sexual Medicine Society of North America also contributed to this study.