There are a variety of complications related to the condition of low testosterone.  Also referred to as hypogonadic (low testosterone) symptoms, such complications vary greatly from mild like minor irritability, to major including erectile dysfunction, loss of libido (sex drive), significant declines in energy levels, increased body fat and reduced muscle mass, depression, memory and sleep complications, etc.  The typically associated causes for low testosterone complications are as numerous and varied as the symptoms themselves.  Such causes are classified into two categories, i.e., primary hypogonadism causes among which are obesity, viral infections, liver and kidney diseases, cirrhosis, alcoholism, etc., and secondary hypogonadism causes such as tumors, surgeries, testicular injuries, genetic conditions like Klinefelter’s Syndrome (an extra ‘X’ chromosome), and many others.  However, low testosterone treatment is very successful and the prognosis for those experiencing this condition is quite good.

The Hormone Testosterone

The hormone testosterone is generated via a joint effort between the hypothalamus and the pituitary gland, then actually produced within the testicles in a system called the Hypothalamus-Pituitary-Testes-Axis (HPTA).  Testosterone serves as the male body’s primary natural hormone, and is responsible for the proper development of male sexual characteristics.  Although routinely described as a sex hormone, testosterone actually governs numerous functions throughout the body including several aspects of development from birth onward.  Testosterone’s duties involve everything from determining gender, and regulating pubertal changes, through providing for male potency (sexual desire & function), to muscle distribution and the partitioning of bodily fat.  It is also an integral part of male well-being, in that it plays a giant role in physiological, biological, and sexual health while influencing such important elements as stress coping capacity, red blood cell count, mental acuity (clarity, focus & concentration, memory & recall), bone density, sperm production, and immune system support.  Although testosterone is a naturally occurring hormone within both males and females, male production is approximately ten times greater.  Thus, complications regarding low testosterone are primarily male-oriented.

Normal Testosterone Levels

The medically accepted ranges for what’s considered the normal upper and lower limits for total serum testosterone levels are 300 to 1,200 ng/dl (nanograms per deciliter) for males, and 30-95 ng/dl for females.  However, for men the Harvard protocol states that optimal total testosterone levels (regardless of age) are 700 to 1,100 (ng/dl).  Male testosterone levels are dictated by age, genetics, lifestyle, and a variety of external influencing variables.  Using accepted averages, men’s testosterone levels breakout by age and level to:  19-24, 700; 25-34, 658; 35-44, 617; 45-54, 606; 55-64, 562; 65-74, 524; 75-84, 471; and 85-100, 376.  Furthermore, testosterone production slowly declines with age at a rate of approximately 1 percent per year, following the age of 30.

Low Testosterone Causes and Symptoms

Low testosterone levels are considered to be those both below and near the bottom lower limit for normal levels.  Therefore, all men with testosterone levels close to or below 300 ng/dl can be effectively diagnosed with low testosterone, and those below 700 ng/dl as out of the optimal range, even though they may or may not actually be experiencing the symptoms of this condition, i.e., not everyone with low testosterone experiences complications as this can be very individual.  However, individuals with levels lower than the lower limit of for normalcy will invariably experience hypogonadic symptoms.  Low testosterone can be the result of routinely consuming hormone injected livestock, andropause (a condition associated with aging in which men secrete lower levels of testosterone resulting in physical and emotional changes),  or a diversity of other possible causes many of which are cited below.

There are two basic forms of hypogonadism namely, ‘primary’ and ‘secondary’.  Either type of hypogonadism may be caused by an inherited (congenital) trait or something that happens later in life (acquired), such as an injury or an infection.  Primary hypogonadism, also known as primary testicular failure, originates from a problem in the testes.  General causes of this condition include:

• Sudden and/or extensive weight loss
• Viral infections
• History of surgery
• Liver and kidney disease
• Specific autoimmune disorders
• Developmental and genetic disorders
• Exposure to radiation or radiation treatment
• Chronic illnesses
• Kidney problems or complete failure
• Liver cirrhosis
• Excessive stress
• Alcoholism
• Obesity 

Secondary hypogonadism indicates a problem in the hypothalamus or pituitary gland, two parts of the brain that signal the testicles to produce testosterone.  The hypothalamus produces gonadotropin-releasing hormone (GnRH), which signals the pituitary gland to make follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Luteinizing hormone then signals the testes to produce testosterone a process known as HPTA.  Specific causes of secondary hypogonadism are:

• Specific medications, like opiates and steroids
• Genetic conditions like Klinefelter’s Syndrome (an extra ‘X’ chromosome)
• Radiation therapy or chemotherapy
• Sarcoidosis, or other inflammatory diseases
• Infections
• Injury to, or loss of the testicle(s)
• Extensive nutritional deficiency
• Too much iron in the body, a condition known as Hemochromatosis
• Recurrent bleeding
• Surgeries
• Bodily traumas
• Tumors 

Although the symptoms of low testosterone may vary from person to person, the general symptoms with which individuals may be stricken are fixed, and regardless of whether the cause is the related to primary or secondary hypogonadism, said symptoms are characterized by:

• More visceral (surrounding and between internal organs) fat
• Loss of bone density and increased risk of breaks, fractures and osteoporosis
• Atypical lipid and cholesterol values
• Reduced body hair (both overall thickness and amount)
• Low hemoglobin levels, with possible mild anemia
• Decreased energy, and activity participation
• Mood changes that can manifest as anger, irritability, fatigue and depression
• Noticeably diminished libido (sexual desire), and lessened sexual functioning
• Reduced capacity to effectively burn body fat as fuel
• Declining lean body mass, and a decrease in muscular strength
• Increase in subcutaneous (beneath the skin) body fat 

Testing for Low Testosterone 

Low testosterone is a condition that is diagnosed in a multi-step process, and can be experienced by both genders as primary hypogonadism emanates from problems with the male testes, as well as with the female ovaries.  Secondary hypogonadism results in a problem with the hypothalamus and/or pituitary gland, and tertiary hypogonadism results from other conditions or external stimuli.  It’s true that endogenous (natural) testosterone levels decline both with age and for a variety of other reasons, however many of the symptoms that lead to a diagnosis of low testosterone can occur so gradually that they may go unnoticed and/or appear nonspecific making them somewhat difficult to identify.  The typical sequence of low testosterone diagnosis is self-reporting, standardized questionnaire, analysis of historical information (personal, sexual, and family), physical exam, and blood test.

This multi-faceted approach to identifying low testosterone greatly reduces the odds of misinterpreted symptoms, which can lead to misdiagnoses and to the unnecessary prescribing of testosterone therapies.  The primary methods for testing for low testosterone are outlined here, and when applied together can conclusively refute or determine the condition of low testosterone.  A noticeable reduction in sexual intimacy due to diminished libido (sex drive or sexual interest), or a reduction in performance (any of a variety of erectile dysfunctions) represent the major reasons men seek clinical low testosterone diagnosis.  However, testosterone is also an important component in sustaining the body’s general balance and overall well-being.  Consequently, additional reasons men both initially self-report low testosterone levels and seek further testosterone testing may involve feelings of excessively depressed mood, muscular weakness, chronic fatigue, and lack of vigor all of which are symptoms common to low testosterone sufferers.  Another form of self-reporting is often initiated by the physician in the form of a standardized assessment tool for measuring low testosterone.  Known as the ADAM (Androgen Deficiency in Aging Men) Questionnaire this elementary 10-question test provides doctors with information in variety of areas that are directly and indirectly related to testosterone levels.  A ‘yes’ or ‘no’ answer on ADAM can help the physician quickly assess the patient’s mood, energy, quality of life (work and play), sleep, sexuality, and stature while serving as a preliminary method for diagnosing low testosterone.  The ADAM questions are as follows:

The ADAM Questionnaire is typically administered to the patient while the physician is collecting a history of symptoms, which includes the compiling of other pertinent historical, sexual, and family medical information.  This information assists the physician in identifying possible hereditary conditions.  Historical profiles include:

FAMILY HISTORY

• Diabetes
• blood diseases (hemophilia or sickle cell)
• alcoholism
• mental illness
• other disorders and conditions
• cancer (all types)
• kidney disease

PERSONAL HISTORY

• social relationship problems -family, work and sexual
• major life changes – births, deaths, adoptions, etc.
• past positive test results
• lifestyle habits – alcohol drinking, smoking, binge eating, etc.
• past and present major and chronic illnesses
• presently taken prescription and non-prescription drugs
• previous medical visits (dates and reasons)
• allergic reactions (medications, foods, air allergens, etc.)
• blood type
• surgeries and dates
• immunization dates
• names of previous and current doctors

SEXUAL HISTORY

• changes in muscular size, strength, and ability to gain muscle
• age of, and number of nocturnal emissions
• sexual activity (intercourse and masturbation)
• changes in hair growth throughout the body
• changes in energy levels
• at birth genital abnormalities
• delayed pubertal development
• rigidity of erections
• frequency of sexual fantasies, desires, and even thoughts

 Next in the line-up of measures is the low testosterone physical examination, which varies at different ages.  The adult male test tends to include visibly quantifiable and tactile assessments of change in areas like:  sleep habits; size of or lump development within the testes, scrotum, breasts, or penis; reduced muscle and/or bone mass; loss of body hair; loss of body weight; and body fat increase.

Usually the last component in the series of low testosterone diagnoses is the blood test.  Testosterone blood tests vary (older ones especially), but a good test uses two samples to measure total testosterone level, and to directly calculate and/or measure the amount of ‘bound’ (unusable or inactive) testosterone and ‘free’ (usable and available for function) testosterone within the bloodstream.  Also used in the calculation of testosterone levels, is a liver synthesized glycoprotein that binds with and disables circulating androgens and estrogens called sex hormone-binding globulin (SHBG).

As the amount circulating testosterone varies throughout the day, blood tests are usually administered in the morning hours between 8:00 AM and 9:00 AM, when blood serum concentrations are at their highest.  The generally accepted total testosterone range, or what is most often referred to as the normal range is 300 – 1,200 ng/dl whereas the optimal total testosterone range is 700 – 1,100 ng/dl.  Thus, scores near the normal lower limit (300 ng/dL), or below the optimal lower limit (700 ng/dl) often receive a low testosterone diagnosis.  Scores under these limits are always considered deficient and consistently warrant a diagnosis of low testosterone.  Whether or not a male is experiencing hypogonadic symptoms is often an individual characteristic, as a score within the lower range may or may not result in negative symptoms.  However, adverse hypogonadic symptoms always accompany low testosterone scores below the lower limit.

Additional tests may be used to accurately diagnosis low testosterone of an idiopathic nature.  Specifically, other tests administered to determine non-hypogonadic cause(s) for a diagnosis of low testosterone may include:

• Pituitary function testing, if the problem is suspected to occur in the pituitary gland.
• A magnetic resonance imaging (MRI), if the problem is thought to occur in the pituitary gland or hypothalamus in the brain. 
• Prolactin level testing, as high prolactin levels can cause low testosterone 
• Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) testing.
• Semen analysis testing.
• Genetic and/or chromosomal  testing, if a genetic condition is suspected 

Testosterone Replacement Therapy 

Testosterone replacement therapy (TRT) is the name of the medically customized treatment of low testosterone.  Administered to restore normal hormonal function, synthetic (man-made) testosterone preparations are prescribed at individualized dosages and frequencies.  When effectively administered, TRT can be used slow and/or completely reverse the negative symptoms which accompany the condition of low testosterone.  Belonging to a class of medications called anabolic steroids, synthetic testosterone supports deficient endogenous testosterone levels by elevating levels back into the normal range, or raising levels high enough within the normal range resolve hypogonadic symptoms.  There are different variations (esters, delivery mechanisms, blends, etc.) of synthetic testosterone each with its own unique properties, and respective methods of action.  For example, injectable solutions are primarily comprised of a singular hormone testosterone with an added ester, which changes the rate (or speed) of the medication’s absorption.  The four primary U.S. approved injectable testosterone preparations for TRT include:  1) short, fast-acting (2-3 days) testosterone propionate; 2) medium, longer-acting (11-13 days) testosterone cypionate; 3) long-acting (14-17 days) testosterone enanthate; and 4) very long-acting 3 months/90 days (2009 FDA approved) testosterone undecanoate, also known as Nebido.  Other injectable preparations include hybrid combinations of fast, moderate, and slow release esters most notably Sustanon 250, and its lesser known hybrid relative Omnadren 250.

Additional TRT forms include:  orals, most often found in tablets which are swallowed and absorbed through normal digestion; transdermals, which include patches and gels that are applied to and absorbed through the skin; subcutaneous crystalline testosterone pellets, which are inserted subcutaneously (between skin layers), and can provide a sustained testosterone release for 3 to 6 months; transbuccal testosterone or buccal testosterone, which is a small, convex, tablet-like system which adheres to gum tissue in the mouth (above the incisors), and is slowly transported from the buccal venous system directly into the superior vena cava – the large vein which returns blood to the heart from the head, neck and both upper limbs.

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