Etiology and Risk Factors of Erectile Dysfunction: Coronary Artery Disease
Tuesday, July 24th, 2012Beyond hypertension, ED may also predict the presence of occult coronary disease. One study evaluated 50 men with ED and no clinical signs of cardiovascular disease. The men were age 40–60 years and underwent cardiac stress testing and coronary angiography.
Eighty percent of the men demonstrated significant cardiovascular risk factors. Stress testing showed myocardial ischemia in 56% of these men. Coronary angiography was performed in 20 of the men with ischemia. Angiography revealed left main stem or severe three-vessel disease in 6 of 20, with some degree of significant coronary artery disease (CAD) in 40% of the total. It is important to note that none of these 50 men showed any clinical signs of ischemic heart disease prior to this testing that was prompted only by the presence of ED.
Thompson et al. reported a secondary finding in a randomized study of almost 10,000 men age 55 or older enrolled in the Prostate Cancer Prevention Trial.
The secondary finding was a direct association between ED and subsequent cardiovascular disease. Eighty-five percent of the men had no cardiovascular disease at the start of the study, with 47% of these men having ED at that time. Incident ED that occurred during the first 5 years of the study was associated with a 1.25 increased risk of subsequent cardiac event during follow-up. In reference to subsequent cardiovascular events, the risk was 0.015 per personyear among those without ED at study entry, and was 0.024 per person-year for those with preexisting ED at the time of study entry. These authors stated that this increased associated risk was similar to the risk associated with smoking or a family history of myocardial infarction, thus clearly echoing the concept that ED should prompt cardiac investigation in these patients.
A smaller investigation using 285 patients looked at the specific extent of CAD in relation to ED. They divided patients into age-matched groups based on acute single vessel disease, acute two or three vessel disease, or chronic coronary syndrome. A control group included those with normal angiography but with suspected CAD. They found that both multiple vessel disease and chronic coronary syndrome were independent predictors of ED. They also found that, in patients with established CAD, clinical presentation of ED comes before CAD in the majority of these patients by an average of 2–3 years.
Although ED has been found to affect about 75% of patients with chronic CAD, the topic is not generally an accepted part of cardiologists’ patient evaluation. Reportedly 25% of these patients experience severe ED. The same study also delved into specific cardiac disease states and their association with various degrees of ED. They found that ED had a prevalence of about 60% in men with a history of prior myocardial infarction or coronary artery bypass surgery.
These authors echoed the assumption that these outcomes were related to endothelial dysfunction and atherosclerosis. They also theorized that the endothelial damage that occurred as a result of smoking, hypertension, lipid disorders, and diabetes diffusely affected vasculature of the body, including the arterial blood supply to the corpora cavernosa of the penis. They warned that ED may be the warning sign for undiagnosed CAD.