'Significant' link found between ED, heart disease

San Antonio-Recently published prospective evidence strongly supports the growing recognition among physicians that erectile dysfunction may be a sign of future cardiovascular disease in some men.

Data from a prospective study of nearly 10,000 men showed that ED is independently associated with subsequent cardiovascular disease, raising the risk of heart disease by 45%, reported lead author Ian M. Thompson, MD, professor and chief of urology at the University of Texas Health Science Center at San Antonio. In addition, three smaller studies examining the ED-heart disease link arrived at similar conclusions, leading experts to advise a thorough evaluation of cardiovascular risk factors in men with ED.

Using data from the landmark Prostate Cancer Prevention Trial, Dr. Thompson and colleagues evaluated the incidence of, and association between, erectile dysfunction and cardiovascular disease in 9,457 men who were included in the study's placebo arm (JAMA 2005; 294:2996-3002). The men were evaluated every 3 months between 1994 and 2003. Erectile dysfunction was determined on the basis of self-reporting and was validated using the Sexual Problems Scale.

After adjusting for possible confounders, the risk of myocardial infarction, angina, or other cardiovascular events remained significantly increased in men with incident erectile dysfunction (HR, 1.25; 95% CI=1.02-1.53; p=.04). A similar analysis found the risk of cardiovascular event was even greater (HR, 1.45; 95% CI=1.25-1.69; p<.001) for men with erectile dysfunction at the time of study entry. Confounding factors included age, blood pressure, serum lipids, diabetes, body mass, family history of myocardial infarction, physical activity, quality of life, and smoking history. Among men without erectile dysfunction at study entry, the unadjusted risk of an incident cardiovascular event was 0.15 per person-year, whereas this risk was 0.24 for men with erectile dysfunction at study entry.

"We have demonstrated that erectile dysfunction is an independent predictor of subsequent cardiovascular disease after controlling for a long list of other factors that are associated with cardiovascular disease," said Dr. Thompson, adding that although previous studies have suggested a link between erectile dysfunction and cardiovascular disease, none has provided prospective analysis with conclusive evidence. "What our study has done is provided as near as conclusive evidence as possible as well as measured the degree of the relationship."

Evidence of connection grows

Additional evidence of the link has emerged from recent studies by three separate research teams. Epidemiologists from the McGill University Health Center in Montreal reported results similar to those of the Texas group. In their study of 3,921 men (ages 40 to 88 years), researchers found that erectile dysfunction was a significant, independent factor for coronary risk (p<.001), as well as undiagnosed hyperglycemia (p=.04), impaired fasting glucose (p=.004), and metabolic syndrome (p<.001) (Arch Intern Med 2006; 166:213-9). In addition, the overall presence of cardiovascular disease was 49.4%, and the presence of cardiovascular disease and diabetes increased the probability of erectile dysfunction, a finding also reported in previous studies (J Am Coll Cardiol 2004; 43:1405-11).

Separately, researchers from the David Geffen School of Medicine at UCLA and the Urologic Diseases in America Project showed that several modifiable risk factors were independently associated with ED, including hypertension (OR, 1.5), diabetes mellitus (OR, 2.69), current smoking (OR, 1.74), and obesity (OR, 1.60). The study was an analysis of data from 3,566 men who were part of the National Health and Nutrition Examination Survey (Arch Intern Med 2006; 166:207-12).