Why Smoking Is Associated with ED
Only those smokers who developed vascular disease were at increased risk of erectile dysfunction
Vascular disease may explain the previously established link between smoking and erectile dysfunction (ED), a Finnish study suggests. Additionally, ED may be a silent vascular disease in ex-smokers.
Rahman Shiri, MD, PhD, of the Tampere School of Public Health, in
ED was three times more likely to develop in those who smoked in 1994 and who had an episode of vascular disease between 1994 and 1999, compared with those who never smoked and who did not experience vascular disease during the period, researchers reported in Urology (2006;68:1318-1322). Smokers who did not have an episode of vascular disease were not at increased risk of ED. Among ex-smokers who had ED in 1994, the incidence of vascular disease was greater than among those who had never smoked and had no ED at entry.
“The link among smoking, ED, and vascular disease may be related to endothelial dysfunction,” Dr. Shiri’s group wrote. “Smoking accelerates the damage to the intima of arteries, causing endothelial dysfunction. Endothelial dysfunction is considered an early phase of atherosclerosis and is associated with several disease states, including vascular disease and its major risk factors.”
Atherosclerosis can play a major role in the development of ED in smokers, the investigators pointed out. Cigarette smoking decreases penile vascular flow, and long-term smoking damages corporal tissue and predisposes impotent men to early atherosclerotic lesions in the cavernous artery, the investigators explained. Coronary atherosclerosis is severe in patients with vascular ED, and ED predicts the presence and extent of subclinical atherosclerosis.
Dr. Shiri’s team found that excess risk of vascular disease among ex-smokers “is consistent with the hypothesis that ED is an early sign of vascular disease caused by smoking.”
Smoking may cause ED through impairment in nitric oxide activity in the penis. “Nitric oxide plays a pivotal role in anti-atherogenesis and is responsible for erection by involvement in the nonadrenergic-noncholinergic neurotransmission that leads to smooth muscle relaxation in the corporus cavernosum.”