Obesity is a common health problem worldwide, often leading to other medical conditions. Men with obesity also tend to have low levels of testosterone, which may further complicate their health. A clinical trial aimed to evaluate the effect of potential therapeutic strategies for low testosterone in men with obesity.
The study recruited 106 men aged 18 to 50 with obesity, low levels of testosterone, and no diabetes mellitus. The men were divided into four groups: placebo, metformin, testosterone, and a combination of metformin and testosterone. The trial was conducted for a year and was randomized, double-blind, and placebo controlled.
The study's primary outcome was the change in insulin resistance measured by the Homeostasis Model Assessment for Insulin Resistance index. The secondary outcomes included changes in testosterone levels, body composition, metabolic variables, erectile function, and health-related quality of life (HRQoL).
The study found that all active groups (metformin, testosterone, and combination therapy) significantly reduced insulin resistance compared to the placebo group. However, combination therapy was not superior to testosterone alone in decreasing insulin resistance. Moreover, there was no evidence of the additive benefit of using metformin and testosterone.
Interestingly, the combination of metformin plus testosterone significantly increased total and free testosterone concentrations compared to the placebo. However, no significant changes were observed in body composition, metabolic variables, erectile function, or HRQoL with any treatment.
Overall, the study suggests that among men with obesity and low testosterone concentrations, all treatment regimens reduced insulin resistance compared to placebo. There was no significant additive benefit from combining metformin and testosterone except for an increase in total and free testosterone levels. Therefore, future studies may be necessary to identify the most effective treatment for low testosterone and insulin resistance in men with obesity.