Can Testosterone Replacement Therapy benefit men aged 60 and over?

By Jayne Warren - 30/04/2008

The risk of osteoporosis (bone fracture) in post-menopausal women is well known - but less appreciated is the fact that some two million men have also been diagnosed with osteoporosis and another three million are at risk. Now a pilot study  has shown that testosterone replacement therapy (TRT) may be beneficial.

 

Gender-based hormones and age are thought to be major factors behind bone fractures in both sexes, as low levels of gender hormones can lead to diminished bone mineral density (BMD - also known as bone mass). Reduced bone density or bone mass means there is less cushioning to protect the bone from cracking in a slip or fall.

 

For this reason, TRT is the standard of care used to improve bone strength and muscle mass in males - but it's use is controversial. Continuous testosterone use has been associated with prostate cancer and high red blood cell levels, and its other effects are not fully known.

 

Now, in one of the first clinical trials involving men over 60-85 years of age, preliminary results indicate that testosterone treatment for five months does have a positive effect on the bone markers of older men. This is the first known study to report on the impact of bone metabolism based on dosing schedules.

 

Older men aged 60 – 85 years took part in the study, and their testosterone levels ranged between 200-500 nanograms (ng) of testosterone per deciliter of blood at the time of enrollment. (Normal limits are considered to be 250-800.) Each was enrolled in one of three double-blinded groups: those receiving continuous weekly intramuscular injections of testosterone for the entire five month period, those receiving weekly testosterone every other month (one month of weekly testosterone/one month of weekly placebo), and those receiving a weekly placebo for the entire five month period.

 

Volunteers also had a whole-body Dual Energy X-Ray Absorptiometry (DEXA) scan at both the beginning and end of the study. Dietary records were obtained and analyzed at regular intervals, as well as fasting blood samples.

 

The research team found that those receiving TRT appeared to have reduced bone turnover, perhaps closing the gap between reabsorption and formation. The impact on bone mineral density was unclear, as were the effects on long-term bone metabolism - but the TRT is expected to have at least a protective effect on existing bone mass by preventing the unwanted increases in bone turnover that are frequently associated with osteoporosis. 

 

Dr. Dillon, the study’s author, commented: “These preliminary data show beneficial effects of TRT on bone turnover markers in older men with low-to-normal testosterone. The effects of sex hormones on markers of bone formation are complex, but this is an important step in understanding how the process works.”

 

The study is reminiscent of the initial research carried out on the female equivalent, HRT - originally hailed as a wonder cure for post-menopausal women. Years later, of course, many women suffered ill-effects and struggled to come off the drugs, and now it is only recommended for use by women of a certain age and for a specific time period. Perhaps, despite these new findings, it would be sensible to wait until the longer-term effects are known before widely advocating the use of TRT ...