Background: Symptoms of male hypogonadism include low libido, fatigue, and dysphoria and are alleviated with testosterone replacement. The prevalence of major depressive disorder (MDD) in hypogonadal men is not known, nor is the antidepressant efficacy of testosterone replacement in depressed, hypogonadal men.
Method: A 6-week double-blind, placebo-controlled clinical trial was conducted in 32 men with DSM-IV MDD and a low testosterone level, defined as total serum testosterone < or = 350 ng/dL. Patients were randomly assigned to receive weekly 1-mL intramuscular injections of either testosterone enanthate, 200 mg, or sesame seed oil (placebo). The primary outcome measure was the 24-item Hamilton Rating Scale for Depression (HAM-D).
Results: Thirty patients were randomly assigned to an intervention; 13 received testosterone, and 17 received placebo. Mean +/- SD age was 52+/-10 years, mean testosterone level was 266.1+/-50.6 ng/dL, and mean baseline HAM-D score was 21+/-8. All patients who received testosterone achieved normalization of their testosterone levels. The HAM-D scores decreased in both testosterone and placebo groups, and there were no significant between-group differences: reduction in group mean HAM-D score from baseline to endpoint was 10.1 in patients who received testosterone and 10.5 in those who received placebo. Response rate, defined as a 50% or greater reduction in HAM-D score, was 38.5% (5/13) for patients who received testosterone and 41.2% (7/17) for patients who received placebo. Patients receiving testosterone had a marginal but statistically significant improvement in sexual function (p = .02).
Conclusion: In this clinical trial with depressed, hypogonadal men, antidepressant effects of testosterone replacement could not be differentiated from those of placebo.