Latest research on men's health issues, treatments and lifestyle practices

Today, leading researchers are gathering at the annual meeting of The Endocrine Society in San Diego to present the latest research on men's health issues, treatments and lifestyle practices. New findings could help doctors identify risks and treat men's conditions more effectively.

Men's health is becoming increasingly important in the medical industry, especially following the introduction of erectile dysfunction drugs to the mass markets. Researchers are looking for ways to increase muscle mass, enhance quality of life and evaluate male behavior all in response to testosterone administration.

The new studies presented below will be presented in a press conference in San Diego on Monday, June 6 at 2:00pm PT, during ENDO 2005, the 87th Annual Meeting of The Endocrine Society.

Effects of Testosterone Dosage on Behavior of Older Males

New research shows that older and younger men experience different reactions to testosterone dosage regarding sexual function and visuospatial cognition and that different aspects of male behavior are affected by testosterone doses.

A group of healthy men, ages 60-75, were prescribed testosterone- production inhibitors and were randomly assigned five dosage levels of testosterone to be taken over a 20-week period. In addition to affecting sexual function and visuospatial cognition, testosterone doses were all tested for their effects on mood. Questionnaires were used to score sexual function based on libido, sexual activity and erectile dysfunction. Based on this questionnaire, libido only increased with testosterone usage in those men that were sexually active at the beginning of the study. Mood was measured by using the Hamilton Depression Inventory and the Young Mania Scale, and no effects of testosterone were observed in either mood rating.

These results indicate that, when taken together with previous data from studies in young men, testosterone dose-response relationships for sexual function and visuospatial cognition differ in older and young men.

Testosterone Replacement Therapy Decreases Fat and Increases Muscle

New studies show testosterone replacement therapy (TRT) in older men decreases fat surrounding the organs and increases skeletal muscle. Prior studies measured the effects of testosterone replacement therapy (TRT) in older men, including obese and non-obese participants, thus skewing the results of baseline fat accumulation in the body.

In an effort to gauge the effects of testosterone replacement therapy in a concentrated, tailored study, healthy 55-year old men with androgen deficiency symptoms participated in a 52-week study and received either TRT or a placebo. Doctors monitored their baseline body mass index (BMI), waist circumference and mean serum.

"Testosterone replacement therapy in healthy aging men decreases visceral fat, the fat that surrounds the organs and increases the risk of developing a variety of diseases," said Carolyn Allan of Prince Henry's Institute of Medical Research. "Controlling visceral fat is important because it can cause cardiovascular disease, insulin resistance and other metabolic problems."

Men of All Ages Respond to Building Muscle Mass with Testosterone Doses

In a new study by Dr. Thomas Storer of Charles Drew University, researchers found older men are just as responsive as younger men to testosterone doses in building muscle mass.

Sixty healthy men, ages 60-75 years, and 61 younger men, ages 18-34, were compared to clarify the relationship of each age group to testosterone and muscle mass building. Subjects were randomly assigned different dosages of testosterone production suppressors as well as varied levels of testosterone doses for 20 weeks.

Muscle function was evaluated based on leg press strength, leg press power and leg press fatigability. Physical performance was evaluated based on stair climb task, 10-meter walk and timed up-and-go. All assessments were conducted at the beginning and end of the study, and results were evaluated based on age and testosterone dosage.

"Healthy, older men demonstrated significant concentration-dependent changes in muscle strength, similar to those observed in younger men during use of graded testosterone doses," said Storer. "Neither young nor healthy, older men showed a testosterone-dose relationship with fatigability or any measure of physical function. Further studies are needed to determine whether testosterone improves physical function in frail, older men."