The decline in testosterone because of aging has been targeted as an obstacle to men fully enjoying their lives. Although there is no proof that testosterone replacement therapy bestows a free pass through "male menopause," physicians continue to write prescriptions by the thousands. In many cases, older men who take testosterone may actually foreshorten their lives because of increased risk for heart disease and other ailments.
A Fountain of Youth?
There is clinical evidence that testosterone replacement therapy poses real risks---heart disease, over-production of red blood cells, breast enlargement and, paradoxically, reduced sperm production or genital shrinkage known as hypogonadism.
Although some men who have tried testosterone supplementation claim to experience weight control and a miraculous restoration of energy and sex drive, its use is considered appropriate only for men who have some type of medical problem that prevents their bodies from producing any testosterone, such infections or tumors that have destroyed the pituitary glands.
Scientifically Unproven Method
"Testosterone therapy remains a scientifically unproven method for preventing any physical or psychological changes that men with normal testosterone levels may experience as they get older," according to the National Institute on Aging, or NIA.
There is not enough clinical evidence to support use of testosterone replacement for healthy older men who do not have "extreme deficiencies" of this hormone, the NIA said. It is difficult to establish a normal range of testosterone, according to the NIA, because many older men have testosterone levels within the "normal range" of healthy younger men.
Testosterone and Heart Disease Risk
A large, multi-center study funded by the National Institutes of Health found that older men with high levels of testosterone were also more at risk for heart disease. The study group included 5,995 American men 65 and older, who were divided into four groups of testosterone ranges to observe trends in cardiovascular events including heart attack, unstable angina, angioplasty or heart bypass graft surgery.
Participants, who were not taking testosterone therapy, were followed in a four-year period from 2002 to 2006. Fourteen percent had a cardiac event, and researchers found that higher testosterone levels "significantly increased" risk for heart disease.
"In our [study], higher endogenous testosterone was associated with an increased risk for coronary heart disease," according to Kristen Sueoka, M.D., of the University of California, San Francisco, one of the researchers.
Controversy Over Treatments
Another study of 209 men 65 and older conducted in Boston to assess a testosterone gel was halted early because of a significantly higher rate of adverse cardiovascular events in men who received the gel, according to the website Endocrine Today. Men in that group initially experienced a surge in physical strength but also had a higher incidence of hypertension, diabetes, elevated cholesterol and obesity.
The study has sparked controversy within the medical community about when, or if, patients should be treated with testosterone. Ronald Tamler., M.D., an assistant professor of endocrinology at Mount Sinai School of Medicine, wrote in the "New England Journal of Medicine" that "truly hypogonadal" patients should continue to be treated with testosterone while cardiac risk factors are studied.
Warning on Abrupt Discontinuation
Dr. Tamler warned that "abrupt discontinuation of testosterone supplementation may lead to increased symptoms of hypogonadism such as decreased libido, erectile dysfunction, decreased lean body mass and dysphoria." Because of the halted study, a goal of "around 500 mg/dL" of testosterone blood levels should be observed in older men who receive testosterone treatment, according to Dr. Tamler.
