The Testosterone Trials are set of multi-institutional, double blind, placebo-controlled studies aimed primarily at determining the efficacy of testosterone replacement therapy (TRT) on sexual function, physical function, and vitality.
- Seven hundred and ninety men over the age of 65 yr with symptoms of hypogonadism and a serum testosterone concentration of <275 ng/dl were randomized to receive either an initial dose of 5 g of 1% testosterone gel or placebo gel once a day.
- Serum testosterone levels and improvement in symptoms were assessed at baseline and at 3 mo, 6 mo, 9 mo, and 12 mo.
- Ninety-one percent of men maintained normalized testosterone levels throughout the duration of the study.
- TRT improved sexual desire (DISF-M-II), frequency of sexual activity (Personality Diagnostic Questionnaire-4), and erectile function (International Index of Erectile Function).
- However, TRT did not confer any significant benefits in terms of vitality.
- In the physical function trial, there was no significant difference between TRT and placebo in terms of the percentage of men with an increase of 50 m or greater in the 6-min walking distance.
- However, on inclusion of all men enrolled in the three trials, TRT was associated with a significantly higher percentage of men with an increase of ≥50 m in the 6-min walking distance.
- More men in the TRT group had an increase in prostate specific antigen ≥1 ng/ml, but there was no difference in the number of men diagnosed with prostate cancer 1 yr after the study period. Similarly, there was no difference in the number of men who experienced major cardiovascular events or died during the study period.
“Re: Effects of Testosterone Treatment in Older Men,” European Urology,2016 September, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5123669/