January 22, 2014
Testosterone Prescribing Often Fails to Follow Clinical Guidelines, Especially in U.S.

Chapel Hill, NC—A lot of the prescriptions filled for testosterone-replacement therapy may be unnecessary, based on clinical guidelines.

That’s according to a new study led by University of North Carolina at Chapel Hill researchers. The report has been accepted for publication in the Endocrine Society's Journal of Clinical Endocrinology & Metabolism and was posted online.

The authors note that, with an aging population and higher incidences of obesity and diabetes, men increasingly may present with low testosterone levels without meeting diagnostic criteria or displaying symptoms of hypogonadism.

“Over the past decade, older and middle-aged men are increasingly being tested for low testosterone levels and being prescribed testosterone medications, particularly in the United States,” said lead author, J. Bradley Layton, PhD. “While direct-to-consumer advertising and the availability of convenient topical gels may be driving more men to seek treatment, our study suggests that many of those who start taking testosterone may not have a clear medical indication to do so.”

A retrospective incident user cohort study was used to study testosterone trends. Researchers analyzed commercial and Medicare insurance claims from the United States and general practitioner healthcare records from the United Kingdom between 2000 and 2011, identifying 410,019 American men and 6,858 U.K. men who began taking testosterone during that time period. Also identified were more than 1.1 million U.S. men and 66,000 U.K. men who had their testosterone levels tested during this time.

The article points out that, since 2000, the number of men beginning testosterone therapy has almost quadrupled in the U.S. while only increasing by a third in the U.K. Yet, most of the patients had not had their testosterone levels measured recently or only had them tested once prior to beginning treatment.

Testosterone testing, although now on the increase in both locations, was found to be more targeted in the U.K.

“Increased testing in the UK has identified more men with low levels, yet U.S. testing has increased among men with normal levels,” the authors write. “Men in the U.S. tend to initiate at normal levels more often than in the UK, and many men initiate testosterone without recent testing. Gels have become the most common initial treatment in both countries.”

"In the United States, we saw a clear trend where more and more men being tested actually had normal testosterone levels and non-specific symptoms,” Layton added. “This is cause for concern as research examines potential risks associated with testosterone use.”

Clinical practice guidelines from The Endocrine Society recommend that testosterone therapy only be prescribed for adult men after making a clinical diagnosis of androgen deficiency with consistent symptoms and testosterone levels below a specific threshold.

“Testosterone testing and use has increased over the past decade, particularly in the U.S., with dramatic shifts from injections to gels. Substantial use is seen in men without recent testing and in U.S. men with normal levels. Given widening use in spite of safety and efficacy questions, prescribers must consider the medical necessity of testosterone prior to initiation,” the authors conclude.

U.S. Pharmacist Social Connect