Testosterone and Spinal Cord Injury by
Stanley Ducharme, Ph.D.
Most people are familiar with the hormone testosterone
and know that it is essential for normal male development.
In high school, we learned that testosterone is essential
for the growth spurt seen in teenage boys and regulates
the sexual drive. In recent years, testosterone has been
the focus of a great deal of research. As a result, scientists
have learned that testosterone has health related benefits
that go far beyond male sexual drive and sex related characteristics.
Testosterone is the most important of the male hormones
and is known as an androgen. The chemical building blocks
for these androgens are steroids and have many important
physiological actions in the adult Testosterone has an
important impact on muscle mass, strength, mood, bones,
hair growth, voice, energy level and sexual drive
In the man, testosterone is produced in the testicles
and in the adrenal glands. The body begins to produce testosterone
before birth and it is at its highest level during adolescence.
This is why young men typically have morning erections
during adolescence and young adulthood. Testosterone levels
are at their daily highest point in the morning.
Unlike women however, who abruptly
stop producing hormones as they age, the man gradually
slows down the production of hormones as he ages. One
study, The Baltimore Aging Study, found that hormone
deficiency was present in 9% of men surveyed in the age
group of 50 to 59, 34% of men aged 60 to 69 years and
68% of men aged 70 to 79 years. Over time, testosterone
levels show a continual, gradual decline. Many scientists
feel that this decline in testosterone is responsible
for many of the symptoms that we normally associate with
the aging process. It is also responsible for what has
been defined as the "male menopause".
Age is not the only factor that lowers testosterone. Some
studies have suggested that medical conditions such as
being overweight and diabetes may lead to lower testosterone
levels. Unfortunately, spinal cord injury also has been
shown to dramatically decrease testosterone levels. Taken
together, age and spinal cord injury can create havoc on
normal hormonal levels.
Men with Spinal Cord Injury
For men with spinal cord injury, lower testosterone levels
also seem to be common early after injury. Some studies
at the University of Missouri have reported that up to
70% to 80% of men with spinal cord injuries have decreased
hormone levels. In men, the specific hormone that decreases
is testosterone. As a result, men with spinal cord injury
can also experience many of the physical and psychological
symptoms of lower testosterone levels. This can create
an unhealthy situation.
For the man with spinal cord injury, the symptoms of lower
testosterone can be especially debilitating. A loss of
muscle mass and strength can affect mobility and functional
independence. Fatigue, loss of energy and moodiness can
ultimately impact on areas such as pressure relief, medication
compliance and health maintenance. Motivation, dry skin
and wound healing can also be affected if hormone levels
are diminished. Finally, many scientists are currently
questioning whether the presence of osteoporosis in people
with spinal cord injuries may be related to lower testosterone
levels along with other factors. Several medical centers
are currently conducting bone density studies to better
understand osteoporosis, testosterone and spinal cord injury.
Thus far, the results are inconclusive but it appears that
testosterone clearly plays a role in the development of
osteoporosis in men with SCI.
In addition to the above issues, the loss of sexual interest,
associated with lower testosterone levels, can add to the
sexual problems already being experienced for the man with
a spinal cord injury. For these individuals, sexual activities
are often seen as added work or as a burden that requires
additional efforts. Naturally, relationship or marital
issues can emerge as the romantic, affectionate and intimate
qualities of a relationship disappear.
Testosterone and Women
For women, the role of testosterone is much less understood.
Nevertheless, for both women with spinal cord injuries
and non disabled women, testosterone, as well as estrogen,
is also important for a healthy libido and sexual functioning.
Women with low testosterone often feel fatigued, have no
energy and lack a sense of wellbeing. Lower testosterone
levels are often associated with lower sexual interest,
decreases in lubrication, painful intercourse and difficulty
in achieving an orgasm. The entire sexual experience becomes
diminished and less fulfilling. Depression is common.
For women, as well as for men, the presence of testosterone
is important in maintaining energy levels, bone density,
mood and strength. Although the level of testosterone may
drop suddenly at menopause, medications have been shown
to interfere with the woman's ability to produce adequate
levels of the hormone. For example, birth control pills
and most anti-depressant medications can reduce the body's
ability to produce an ongoing supply of testosterone.
Testosterone Replacement Therapy
To determine if hormone levels have decreased after injury,
a simple blood test is usually required. This can be completed
at the doctor's office and the results are then compared
to men of the same age group who do not have a spinal injury.
If the doctor determines that testosterone therapy is the
best course of action to treat the problem, he or she will
recommend one of the several available delivery methods.
Generally, these include injections, patches or various
gels. For men with spinal cord injury, many doctors have
found that a monthly injection of testosterone significantly
decreases the symptoms of androgen deficiency.
It is important to remember that there are
risks associated with testosterone therapy and that it
is a medication designed to treat a disorder. It's not
a substance to enhance a lifestyle or to be taken for an
energy boost. Receiving testosterone therapy is always
conducted under careful medical supervision and requires
ongoing monitoring of blood levels. Taking testosterone
may be beneficial to many people but can also aggravate
sleep disorders, stimulate enlargement of the prostate
gland and trigger urinary problems. It can also cause more
minor issues such as an increase in facial hair and acne.
Research is Needed
In conclusion, hormones and especially testosterone play
a critical role in maintaining a healthy body and a healthy
sexual appetite. Lower levels of testosterone have been
recently identified in individuals with spinal cord injury
and more attention is now being given to the adverse affects
of lower levels on the aging process. Scientists are concerned
about poor wound healing and unhealthy bones when hormone
levels are too low in people with spinal cord injuries.
Testosterone replacement therapy for people with spinal
cord injuries is till somewhat controversial but gaining
much more acceptance among medical professionals. In larger
medical centers, this is a physiological condition which
is being treated by, endocrinologists, urologists and physiatrists.
Testosterone replacement is one more area in which we will
continue to see research on this topic. In the meantime,
if symptoms are present, it is certainly worth discussing
with your doctor.