Testosterone is the predominant sex hormone in men. In puberty, testosterone levels rise can remain in normal range as men age, unlike in women who experience menopause. Some men will however, have lower levels of testosterone and experience symptoms at different times in their lives. Low levels can occur even in younger men in their 20’s and 30’s. Environmental factors can contribute to lower testosterone including xenoestrogen exposure, stress, and nutrient deficiencies.
Low levels of testosterone are associated with low libido, erectile dysfunction, fatigue, depression, osteoporosis and cognitive decline. Contrary to the popular belief, low levels of testosterone are linked to increased risk of prostate cancer. Replacement with testosterone can unmask a pre-existing prostate cancer. Screening for prostate cancer is recommended before and within the first few months of treatment, then every 6 months. If the levels are stable, then once a year.
Testosterone replacement has become more common as men age and experience symptoms of low levels. For men, hormone replacement therapy can be life changing, improving sexual function, mood, cognitive function and physical endurance. Side effects of testosterone can be increased aggression, hair loss, acne, and increased red cell count. There can be changes in the testicles and decreases in seminal fluid. Testosterone can be administered in topical forms, gels, creams or by injection.
For years, research supported that use of testosterone was associated with reduced risk of cardiovascular disease. One recent study reported a different outcome causing questions about the safety of testosterone replacement in men. Since then there have been many editorials disputing these findings and corrections to the statistical analysis by the authors.
In 2013, a UCLA Veteran’s Administration of study of 8709 men reported that replacement of testosterone was associated with increased risk or heart attack, stroke and death. Since the publication there were many questions about the statistical analysis used in the study and the design of the study. It didn’t really monitor the patients and screen the patients for increased risk factors. It was only a 90 day study and didn’t validate if the patients who were prescribed the testosterone even took it properly.
Another study from the University of Texas followed 6000 men treated with testosterone from 1997 to 2005 and compared them with 19,000 men who were not treated. They did not find any increase risk of heart attack. Currently the FDA does not support that testosterone therapy is associated with risk of heart attack and stroke.
Testosterone levels are best checked in the morning. Both total and free testosterone levels should be measured. Testosterone circulates in the blood and much of it is bound to a protein called sex hormone binding globulin(SHBG). That is why it is important to check both the total and the free testosterone. It is also important to monitor adrenal function, DHEA and estradiol in men. Supplements and herbs can help improve testosterone levels in some men. When testosterone replacement is necessary and it can be life changing.
Asian J Androl 2015;17:26-31