Why are so many men taking testosterone therapy?

As a medical provider I have noted that a fair number of male patients over the age of forty are taking testosterone replacement therapy. Most of these individuals seem to be totally healthy aside from seeking my care for a painful shoulder. This has caused me to question, “What are the indications for testosterone replacement therapy in men? Do most of my patients need or benefit from this?” 

Here is a brief review of what I have learned on this topic: Testosterone is a hormone normally produced by men. It is involved in regulating body fat, muscle mass, bone density, sexual drive, mental acuity and fertility. Some might say it promotes “vigor”.  As we age we naturally produce less testosterone, this is a fact of life and normal. This in part contributes to some of the changes men experience as part of aging; changes in body fat distribution, decreased muscle, decreased sex drive and fertility. 

Who should be treated?

There are definitely some men who should be taking testosterone replacement. Specifically, men who are being treated for infertility or sexual dysfunction by a urologist or endocrinologist, and who have very low testosterone levels. However, the majority of men taking testosterone do so for other reasons such as decreased energy and changes in body appearance.   In these cases it can be difficult to determine if this is being caused by abnormal testosterone production (which should be treated) or if the individual is just aging normally.

Is there a good test to determine if I need testosterone therapy?

Part of the problem is that there is not a clear-cut test for this. We can measure the amount of testosterone present in the blood and this is called the serum concentration. However, there is normal variability in the serum concentration. One person might have a lower amount of testosterone but it may be more than enough for his body. While another man may have a higher level but have symptoms of testosterone deficiency. 

It has been said that levels of 300 nanograms per decileter (ng/dl) are the lower limit of normal, and levels below 200 are clearly abnormal. But we can see from the graph below that a large number of normal fifty year olds would test positive if we use cutoffs of 300 or even 200. So the lab test is a little vague.  Furthermore, the symptoms are also non-descript. As we age, who doesn’t get a little fatter and have less energy.  In this situation, there is potential for lots of men to be diagnosed and treated for “low testosterone” who might actually be normal. Don’t forget this is big business for pharmaceutical companies, who would like us all to buy their medicine.

Does it work?

It is unclear if testosterone therapy has any health benefits for healthy older men.

See the information from Mayo Clinc

http://www.mayoclinic.org/healthy-living/sexual-health/in-depth/testosterone-therapy/art-20045728

Does it do any harm?

At this point there is not evidence that testosterone replacement at medical dosages will have negative affects. However, there is a lot that we don’t know. As a cautionary note, hormone replacement therapy for women was thaught to be safe and beneficial for many years. More recently we have learned that female hormone replacement therapy may increase the risk of heart disease and cancer in some women.

Final thoughts

At first glance it would seem that all aging men would benefit from testosterone replacement. Who wants to be fat, bald and impotent? On the other hand, is it really the role of the medical profession to fight the aging process? Our experience with hormone replacement in women suggests that there may be unintended consequences when we try to meddle with the natural aging process.