Erectile Dysfunction and Subsequent Cardiovascular Disease. Ian M. Thompson, MD; Catherine M. Tangen, DrPH; Phyllis J. Goodman, MS; Jeffrey L. Probstfield, MD; Carol M. Moinpour, PhD; Charles A. Coltman, MD. JAMA. 2005;294:2996-3002.

"More than 10 million men in the United States are affected by erectile dysfunction, with an estimated 100 million men affected worldwide. The risk of erectile dysfunction is related to many factors, including age, smoking, diabetes, heart disease, depression, and hypertension. Because cardiovascular disease and erectile dysfunction share etiologies as well as pathophysiology (endothelial dysfunction) and because of evidence that degree of erectile dysfunction correlates with severity of cardiovascular disease, it has been postulated that erectile dysfunction is a sentinel symptom in patients with occult cardiovascular disease. To examine this hypothesis, we studied a cohort of men who were assessed prospectively for both of these diseases over the course of 7 years.

…Erectile dysfunction is a harbinger of cardiovascular clinical events in some men. Erectile dysfunction should prompt investigation and intervention for cardiovascular risk factors…"