Mens bodies tend to produce less testosterone as they age, and some doctors have begun prescribing supplements of the hormone to increase libido and treat other age-related problems in men.

The men in the study with higher levels of bioavailable testosterone, the testosterone that can reach the brain, did significantly better on these cognitive tests than men with lower levels, said lead author Kristine Yaffe, MD, UCSF assistant professor of psychiatry, neurology and epidemiology and biostatistics, and chief of geriatric psychiatry at SFVAMC.

However, Yaffe does not recommend that men begin taking testosterone to improve cognition. Our study only looked at natural testosterone levels and so it doesnt prove that testosterone supplements can prevent cognitive decline. We will need results of large randomized clinical trials in older men before we can confidently say that testosterone supplements are beneficial and safe, she said.

Taking testosterone, or over-the-counter supplements that boost levels of the hormone, can have side effects including increased risk of prostate cancer, increased cholesterol levels, acne and male pattern baldness, Yaffe said. Although some previous studies have suggested that testosterone might benefit the brain, most of these studies were of younger men, she said.

The study, which was published in the April issue of the Journal of the American Geriatrics Society, looked at 300 older men enrolled in a larger study of risk factors for osteoporosis in men that included cognitive testing.

The cognitive tests measured concentration, memory, attention, language, and other cognitive skills.
'"/>

Contact: Kevin Boyd
kboyd@pubaff.ucsf.edu
415-476-8429
University of California - San Francisco
15-Apr-2002