Posts Tagged ‘pituitary’

Testosterone Update 2017: Untangling The Web

January 21, 2017

Andrew Siegel, MD   1/21/17

Testosterone deficiency (TD) is a not uncommon male medical condition marked by characteristic symptoms and physical findings in the face of low levels or low activity of testosterone (T). TD is most often seen in men above the age of 50 years and is a frequent reason for why men make appointments with urologists.


What are the 3 best predictors of TD?

1. Decreased sex drive

2. Erectile dysfunction (ED)

3. Decreased frequency of morning erections

T is a hormone that is essential to male vitality. TD can affect the function of many different organ systems and negatively impact one’s quality of life. Its signs and symptoms can vary greatly. Since T regulates the male sexual response—including desire, arousal, erections, ejaculation and orgasm—sexual dysfunction is a common component of TD and is often the presenting symptom. Low T can give rise to diminished libido, altered penile rigidity, decreased morning and nocturnal erections, decreased ejaculate volume and has been associated with delayed ejaculation. Other common symptoms are decreased energy and vigor, fatigue, muscle weakness, increased body fat, depression and impaired concentration and cognitive ability. Common signs are weight gain, visceral obesity (increased waist circumference), decreased muscle mass and bone density, decreased body and pubic hair, gynecomastia (male breast development) and anemia.

TD is often seen in men with chronic diseases including obesity, diabetes, metabolic syndrome, osteoporosis, HIV infection, opioid drug abuse, and chronic steroid usage.

Why does TD occur?

TD can result from a problem with the ability of the testes to produce T, or alternatively, because of an issue with the hypothalamus or pituitary gland in which there is inadequate production of the hormones that trigger testes production of T. At times there is adequate T, but impairment of T action because of inability of T to bind to the appropriate receptors. Additionally, increased levels of sex hormone binding globulin (SHBG), a molecule that binds T, can result in decreased levels of “available” T despite normal T levels.

Not an Exact Science

It is important to note that not everybody who has a low T level will have characteristic signs and symptoms and also that it is possible to have signs and symptoms of TD with a normal T level.

 Checking for TD should be done under the circumstance of a male complaining of any of the aforementioned symptoms and signs. Shortcomings of measuring T levels are results that can vary from laboratory to laboratory, a lack of a consistent and clinically relevant reference range for T, the variability of T levels depending on time of day that levels are drawn (values are highest in the early morning) and the fact that it is the free T and not the total T (TT) that is “available” to most tissues. T circulates in the blood mainly bound to proteins (SHBG and albumin). It is free T and albumin-bound T that are tissue “available” and active.

If TT and/or free T are low, the levels of the pituitary hormones luteinizing hormone (LH) and prolactin (P) levels should be obtained to distinguish between a pituitary versus a testes issue. Symptomatic men with a TT < 350 are candidates for treatment. A 3-6 month trial of treatment may also be considered in men with symptoms and signs, but without definitive TD on lab testing since there is no absolute T level that will reliably distinguish who will or will not respond to treatment.

T and Prostate Cancer

Although testosterone deprivation has proven effective in treating advanced prostate cancer, there is no evidence to support that treatment of TD with T will increase the risk of prostate cancer. Studies indicate that if T < 250, increasing levels of T will stimulate prostate growth, but once T > 250, a saturation point (threshold) is reached with further increases in T causing little or no additional prostate growth.

T and Cardiac Disease

 A broad review of many articles fails to support the view that T use is associated with cardiovascular risks. In fact, the weight of evidence suggests that treating TD offers cardiovascular benefits.

T and Fertility

T causes impaired sperm production as T is a natural contraception and T replacement should not be used in men desiring to initiate a pregnancy.

TD Treatment

There are numerous different means of T treatment. T pills are not a satisfactory option since testosterone is inactivated in its pass through the liver. There is a buccal formulation that is placed and absorbed between the gum and cheek. There are numerous skin formulations including patches and gels. These skin formulations are commonly used, but are expensive, carry the risk of transference to children, spouses, and pets, and can cause skin irritation. They have the advantage of flexible dosing, easy administration, and immediate decrease in T levels after stopping treatment. Long-acting T pellets can be implanted in the fatty tissue of the buttocks, generally effective for 3 to 4 months or so. The insurance hoops that are required to get this formulation approved and covered have proven to be a major challenge. T injections are also commonly used, typically using a slowly absorbed “depot” injection that, depending on the dosage, can last 1-3 weeks. There is also a very long-acting formulation that, like the T pellets, requires a very taxing process to gain insurance approval.

As an alternative to T replacement, clomiphene citrate is a selective estrogen receptor modulator that when taken on a daily basis will increase both testosterone levels and sperm count by stimulating natural testes production. Human chorionic gonadotropin (hCG) can be used as well. Advantages are that they stimulate natural testosterone production and do not impair sperm count.

Adverse Effects of T Treatment

Careful monitoring is imperative for anybody on T treatment. T levels must be checked in order to assure levels in the proper range. Prostate exams and PSA levels are used to monitor the prostate gland and a periodic blood count is performed to ensure that one’s red blood cell count does not becoming too elevated, which can incur the risk of developing blood clots.

It is important to understand that external T will suppress whatever natural T is being made by the testes, since the body recognizes the T and the testes loses its stimulation to produce both T and sperm. Long term T use can cause atrophy (shrinkage) of the testes.

Ongoing Treatment

Those patients who are experiencing benefits of T treatment can have periodic “holidays” of discontinuation to reassess the continued need for the treatment.

Excellent resource: Diagnosis And Treatment Of Testosterone Deficiency: Recommendations From The Fourth International Consultation For Sexual Medicine, Journal of Sexual Medicine 2016; 13:1787 – 1804

Wishing you the best of health,

2014-04-23 20:16:29




