It becomes more difficult to use erectile dysfunction (ED) as an indicator of cardiovascular (CV) disease as age increases, according to a report in the February 2009 issue of the Mayo Clinic Proceedings.

Analysis has shown that the prognostic value of ED for risk of cardiovascular disease is much higher for men who have suffered erectile dysfunction in their 40s, but significantly lower for men who experience erectile dysfunction in their 70s.

According to a study carried out by Duke University Medical Centre, the long period between the diagnosis of erectile dysfunction and the onset of cardiovascular events “raises the possibility of a window of curability, whereby the progression of cardiac disease might be slowed or halted by some form of medical intervention."

The study, which began in 1990, consisted of 1402 randomly selected white men between the ages of 40 and 79. It was required that they fill out a “sexual function” questionnaire every two years for the Olmsted County Study of Urinary Symptoms and Health Status Among Men. Cardiovascular conditions of the men were monitored through a coronary artery disease (CAD) surveillance program.

The co-author of this research, Dr Jennifer L. St. Sauver, says that this is a third study to indicate that erectile dysfunction can be foretelling of an event of cardiovascular disease in men. She added: "One of the things we'd like to see is a clinical trial with men with erectile dysfunction at these younger ages that looks at whether interventions can reduce the risk of heart disease later in life."

In the research editorial, Dr Martin M. Miner of Miriam Hospital mentions that erectile dysfunction has previously been linked with a 45% increased risk of cardiovascular disease over a five year period. In this earlier study, men over the age of 55 were tested in a placebo-control group of a prostate cancer clinical trial. This study showed that erectile dysfunction was as much of an indicator of cardiovascular disease as the more traditional ones like family medical history, smoking and hyperlipidemia.

The new study showed similar results, and Dr Robert A. Kloner, an ED and cardiovascular disease researcher who was not involved in the study said: "It's looking at a wider array of men, and it finds a signal that ED is really a very important predictor, especially for men under the age of 60, and I don't think that was known before... It's certainly consistent with what we've known and sheds new light on the importance of ED in younger men."

He continued to say that if a young man with erectile dysfunction seems to have no problem with his genitals after a physical examination, then factors that lead to a risk of cardiovascular disease should also be thoroughly checked.

Dr Ajay Nehra from the Mayo Clinic explained that ED and CV disease share many of the same risk factors as well as pathophysiology and suggests that ED is a "sentinel marker" of endothelial dysfunction and is therefore a silent peripheral vascular disease. In his review of the three available phosphodiesterase-5 inhibitors (sildenafil, tadalafil, vardenafil - Viagra, Cialis, Levitra respectively) he writes, that the drugs have "no adverse effect on cardiac contraction, ventricular repolarisation or ischemic threshold,” and that “there was no evidence of increased cardiovascular risk from using any of these agents."

Of those who took part in the study, 2.4% experienced erectile dysfunction in their 40s compared to 38.8% in their 70s. Out of the whole study group, 11% suffered an occurrence of cardiovascular disease, including MIs and sudden cardiac deaths, in the following 10 years.

Because ED will often accompany diseases like diabetes, hypertension and/or dyslipidemia, a younger person with ED should also be screened for high blood glucose, lipids, cholesterol and blood pressure. A lot of pharmacies will now offer such screening making it more accessible, affordable and discreet.

The study was partly funded by Merck Research Laboratories and the National Institutes of Health. Dr. Nehra is a consultant for Pfizer, GlaxoSmithKline, and sanofi-aventis. Dr. Kloner is a speaker or consultant for Pfizer and Lilly.

L.W.