I know that this website is geared to and read by women (mostly my patients), but many of us do have men in our lives. As they (and their partners) get older they question whether they need additional male hormone (testosterone) to feel as good as they felt when they were young. There is a huge “testosterone replacement market” and millions of prescriptions have been written and injections given without peer-reviewed, large, double blinded studies to back up the efficacy and safety of testosterone therapy for men as they age. The public is bombarded by the media in an effort to create awareness about the symptoms of testosterone deficiency. Direct to consumer advertising claims (amidst pictures of men running and engaged in outdoor and indoor activities with gorgeous women) that testosterone will take care of symptoms such as decreased libido, sexual disorders, fatigue and diminished fitness.
This week’s New England Journal of Medicine published a long article on the effects of testosterone treatment in older man and I wanted to touch on this (well perhaps touch was not the right word…)
There is no question that testosterone concentrations in men decrease with increasing age. In 2003, The Institute of Medicine concluded that there was insufficient evidence that testosterone treatment was beneficial in older men and recommended that clinical trials be conducted. So, “The Testosterone Trial” was set up and funded by the NIH. It consists of seven double blinded, placebo controlled trials conducted in 12 sites. The participants were assigned to receive testosterone gel or placebo for one year. The effect of the hormone therapy was assessed at baseline and at 3, 6 ,9 and 12 months. The article describes the efficacy results for three of the main trials as well as adverse events in all the participants in these trials.
The trial recruited the participants through mass mailings. The call went out for men who were 65 years or older who had low serum testosterone levels. The researchers did not want to include men with a history of prostate cancer, a high risk of prostate cancer or those who had significant heart disease or risk for heart disease. I guess the mass mailings worked… initially 51,085 men wanted to enroll but eventually in the three published trials most were eliminated and only 790 met all the criteria, including a sufficiently low testosterone level (below 275 ng/dl).
Half of the men were given testosterone through a preparation called AndroGel 1% in a pump bottle. The other half were given a similar looking gel which was a placebo. The serum testosterone levels were measured at months one, two, three, six and nine and the dose of testosterone gel was adjusted after each measurement in those on the hormone in an attempt to keep the concentration within the normal range for young men (19 to 40 years old).
The researchers found that testosterone treatment did increase serum testosterone levels to that mid normal range and that this was associated with a significant increase in their sexual activity. The men underwent questionnaires and were given something called a PDQ – Q4 score. They found that there was an increase in sexual desire and increased erectile function in men in the testosterone group as compared to those on placebo and the men also reported that their sexual desire had improved since the beginning of the trial. Physical function was checked by looking at the percentage of men who increased the distance walked in a six minute walk test. Vitality was checked by the percentage of men who score on a FACIT – fatigue scale who increased their score by at least four points. (I know this is more than any of us need to know, but to simplify in addition to these scores, every three months the participants were also asked about their general impression of their change in sexual desire, walking ability or energy and overall health.)
The percentage of men who had an increase in their ability to walk a longer distance during the six minute walking test was not significantly improved. Testosterone had no significant benefit with respect to vitality. The men who received testosterone reported slightly better mood and lower severity of depressive symptoms than those who receive placebo. The rates of adverse events were similar in the two groups.
The conclusion: Men 65 years of age or older who initially had low testosterone levels and who had them raised for one year to the mid normal range for men 19 to 40 had a moderate benefit with respect to sexual function and some benefit with respect to mood and depressive symptoms. But there was no benefit with respect to vitality or walking distance.
The authors did state that there was a limitation in the study because the results apply only to men 65 years of age or older whose testosterone levels are found to be quite low. They also felt that these results together with other trials that are now completed (but not published in this article) “should help inform decisions about testosterone treatment for men 65 years of age or older whose levels are low for no apparent reason other than age.” I guess a lot of men in this age group will now have their levels checked…