MONTREAL — Hypogonadism should be considered a risk factor for cardiovascular disease in older men, Dr. Andre T. Guay said at a congress sponsored by the Canadian Society for the Study of the Aging Male.
He based that conclusion on an analysis of testosterone levels in 154 men with an average age of 53.5 who were seen at the erectile dysfunction (ED) clinic of the Lahey Clinic Medical Center, Peabody, Mass., where Dr. Guay is an endocrinologist.
Overall, 25% of the men had hypogonadism, defined as a free testosterone level below 10 pg/mL. Among men with low testosterone, 92.3% had insulin resistance, compared with 25.2% of those without low testosterone levels. High rates of metabolic syndrome also were seen among hypogonadal men, using both the NCEP criteria and the more stringent World Health Organization criteria for metabolic syndrome. (See box.)
In a previous study, 91% of the cohort of men seen in the ED clinic had cardiac risk factors. A total of 43% had hypertension, 73% had dyslipidemia, and 85% had a body mass index greater than 25 kg/m
Additionally, 43% of the men had metabolic syndrome, according to the National Cholesterol Education Program (NCEP) criteria, compared with 24% of the general population. Insulin resistance was found in 79%, compared with a 25% incidence in the general population.
These findings suggest that ED may be an early warning sign of cardiac disease, he said.
The new findings on hypogonadism go beyond the link between ED and cardiac risk, suggesting that low testosterone also may be associated with cardiovascular disease, according to Dr. Guay.
Several large reviews have indicated that men with low testosterone have increased cardiovascular risks, with a high incidence of metabolic syndrome and insulin resistance.
“There are associations, but that doesn't necessarily prove cause and effect,” Dr. Guay said in an interview. “However, we know that testosterone can positively affect endothelial function, increasing blood flow, and we know that even acute stimulation of testosterone can decrease insulin resistance, which is the basis of the metabolic syndrome and many chronic diseases. Testosterone must therefore have a protective effect on the vascular lining where atherosclerosis begins.”
The study findings suggest that “when patients present with ED, you should immediately look for major cardiac risks and either treat or refer for treatment. It also may be that we should be checking the testosterone level in every man with ED,” he said at the meeting, which was cosponsored by the International Society for the Study of the Aging Male.
ELSEVIER GLOBAL MEDICAL NEWS