Age Affects Link Between Erectile Dysfunction, Coronary Artery Disease
Erectile dysfunction (ED) in men aged 40-49 years is associated with a pronounced increase in the risk of future coronary artery disease (CAD), according to researchers. In contrast, ED in older men appears to be of less prognostic significance, they noted
“Younger men with ED may be ideal candidates for cardiovascular risk factor screening and medical intervention,” the investigators concluded.
Brant Inman, MD, and colleagues at the Mayo Clinic in Rochester, Minn., screened biennially for ED in a group of 1,402 community-dwelling men with regular sexual partners and without known CAD. During the 10-year follow-up period, CAD developed in 156 men (11.1%). ED was associated with a significant 80% increased risk for developing CAD after adjusting for diabetes, hypertension, smoking status, and BMI, the investigators reported in Mayo Clinic Proceedings (2009;84:108-113).
Among men without ED at baseline, the CAD incidence rates per 1,000 person-years were 0.94, 5.09, 10.72, and 23.30 for men aged 40-49 years, 50-59 years, 60-69 years, and 70 years and older, respectively. In contrast, for men with ED at baseline in these age groups, the rates were 48.52, 27.15, 23.97, and 29.63, respectively.
Dr. Inman and his colleagues noted that blood vessel size could partially explain why ED precedes other manifestations of systemic atherosclerosis. Penile arteries typically are 1-2 mm in diameter, they said, whereas the coronary arteries are 3-4 mm in diameter and the carotid arteries are 5-7 mm in diameter.
“Therefore, an atherosclerotic plaque of a given size should occlude and hemodynamically affect a penile artery earlier than [it would] a coronary or carotid artery,” the authors explained. “The essential idea is that smaller arteries plug earlier than larger arteries.”
With respect to study strengths, the researchers stated that they actively ascertained erectile status using validated biennial questionnaires specifically designed to measure diverse aspects of male sexual function.
They also pointed out that subjects were randomly selected from a geographically fixed community, so the study lacks many selection biases that may be present in studies that include patients recruited from physicians' clinics or clinical trials. One of the study's limitations is that subjects came from a largely white community, which “raises the possibility of race-specific ED effects that may not be generalizable to other ethnic groups.”