A new study in the Journal of the American Medical Association found that older men with age-related memory problems and testosterone deficiency did not experience an improvement in memory or cognitive performance after taking testosterone replacement therapy for one year. This finding goes against previous research in which investigators reported an association between verbal memory and testosterone among older men with a T deficiency.
One reason it’s believed that testosterone may help with verbal memory is that the area of the brain associated with this function—the hippocampus—also has receptors for testosterone. Therefore, the more testosterone interacts with these receptors, perhaps the better the performance on verbal memory.
However, the results of this study suggest otherwise. A total of 493 older men (mean age, 72.3 years) who had age-associated memory problems and low testosterone (234 ng/dL at baseline) were assigned to take either testosterone replacement therapy (1% testosterone gel, beginning with 5 g daily and then adjusted) or placebo for one year. The participants were tested on delayed paragraph recall, visual memory, executive function, and spatial ability at baseline and at six and twelve months.
Researchers did not detect any significant change in any of the men’s ability to recall a spoken paragraph after a time lapse, nor any significant improvements in the other factors tested. Based on the findings of this study, the authors concluded that “This study does not support the use of testosterone for the treatment of age-associated memory decline in older men with symptomatic hypogonadism.”
The authors also noted that the men who took the testosterone replacement therapy were more likely to develop erythrocytosis (abnormally high red blood cell mass at or greater than 17.5 g/dL), which is characterized by a greater risk of thromboembolism, or a blood clot that is transported to the brain (stroke), lung (pulmonary embolism), or other parts of the body.
Read more in our Low T Health Center.
Resnick SM et al. Testosterone treatment and cognitive function in older men with low testosterone and age-associated memory impairment. JAMA 2017; 317(7): 717-27