More than $100 million was spent by drug companies on advertisements for androgen replacement therapy (ART) in 2012. The ads appear to be successful because the number of prescriptions for ART among men 40 years or older has more than tripled since 2001 (JAMA Intern Med online June 3, 2013). Interestingly, among all new androgen users, only 74.7% had their testosterone level measured in the prior 12 months. The proportion of men with low testosterone could not be determined in this study. Common diagnoses in the year prior to testosterone replacement therapy included hypogonadism (50.6%), fatigue (34.5%), erectile dysfunction (31.9%) and psychosexual dysfunction (11.8%).
Despite the claims touted in these ads, randomized clinical trials have shown that testosterone therapy results in only small improvements in lean body mass and body fat, libido, sexual satisfaction and has inconsistent or no effect on weight, depression, and lower extremity strength (J Clin Endocrinol Metab 2010;95(6):2536-59). Testosterone treatment has been associated with numerous adverse effects including polycythemia, gynecomastia, edema, prostate cancer, benign prostatic hyperplasia and coronary artery disease.
Two articles published on February 3 in the New York Times further highlighted the cardiovascular risks associated with androgen replacement therapy in men (Don’t ask your Doctor about Low T by John La Puma and Weighing Testosterone Benefits and Risk by Roni Caryn Rabin) Hopefully, coverage in the popular press will be more successful in decreasing this harmful practice than the medical profession has been.
The Endocrine Society Clinical Practice Guideline does not recommend screening for androgen deficiency in the general population. The Guideline recommends making a diagnosis of androgen deficiency only in men with consistent symptoms and signs and unequivocally low serum testosterone levels. The initial test should be a total testosterone level measured on a sample collected during the morning. Low levels should be confirmed by repeat testing of total testosterone. Men who have total testosterone levels near the lower limit of normal or who may have a sex hormone binding globulin abnormality can be further investigated using bioavailable testosterone levels.
Common practice has been to order both total and free testosterone in the evaluation of testosterone deficiency. To meet the growing demand, most laboratories measure free testosterone with an automated androgen analog immunoassay. Unfortunately, an increasing number of studies have demonstrated that these free testosterone assays do not accurately measure free testosterone and are often falsely low. The Endocrine Society recommends against the use of automated free testosterone assays (J Clin Endocrinol Metab 2010;95(6):2536-59).