Low serum testosterone levels in men has been associated with an increased risk of diabetes mellitus, obesity, metabolic syndrome, osteoporosis, cardiovascular events, and all-cause mortality. Numerous studies evaluating testosterone supplementation have described beneficial effects including increased strength and muscle mass, libido, bone mineral density, and insulin sensitivity.
An observational, retrospective cohort study of multiple Veterans Administration (VA) centers in the Northwest US identified 1031 hypogonadal men with serum testosterone < 250ng/dl and age greater than 40 years with no history of prostate cancer. Testosterone supplementation was given to 398 men (39%). The mortality rate in men treated with testosterone was 10.3% compared to 20.7% in untreated men with a mortality rate of 3.4 deaths per 100 person-years for men treated with testosterone and 5.7 deaths per 100 person-years in untreated men (hazard ratio – 0.61).
The authors conclude that testosterone supplementation was associated with decreased mortality compared to no treatment, the first trial to specifically examine this relationship. One limitation of the study is that the men had an average of 7 pharmacologically-treated medical conditions, as 21% had coronary heart disease and 38% had diabetes. The authors acknowledge that larger-scale randomized trials are needed to gain an improved understanding of the relationship between improvement in mortality outcomes and low serum testosterone in hypogonadal older men.
Reference: Shores MM, Smith NL, Forsberg CW, et al. Testosterone treatment and mortality in men with low testosterone levels. J Clin Endocrinol Metab 2012;97:2050-2058.