| Osteoporosis
in Men
Osteoporosis, a disease that causes the skeleton to weaken and
bones to break, is a significant threat to more than two million
men in the United States today. Experts estimate that one-fifth
to one-third of all hip fractures occur in men and that symptomatic
vertebral (spine) fractures occur about half as often in men as
in women. After age 50, six percent of all men will suffer a hip
fracture as a result of osteoporosis. In 1994, osteoporotic fractures
in men accounted for annual costs of $2.7 billion, or one-fifth
of the total cost of osteoporotic fractures in the U.S.
Despite these compelling figures, a majority of American men view
osteoporosis solely as a "woman's disease," according
to a 1996 Gallup Poll. Moreover, among men whose lifestyle habits
put them at increased risk, few recognize the disease as a significant
threat to their mobility and independence.
Osteoporosis develops less often in men than in women because men
have larger skeletons, bone loss starts later and progresses more
slowly, and there is no period of rapid hormonal change and accompanying
rapid bone loss. However, in the last few years the problem of osteoporosis
in men has been recognized as an important public health issue,
particularly in light of estimates that the number of men above
the age of 70 will double between 1993 and 2050.
Clearly, more information is needed about the causes and treatment
of osteoporosis in men, and researchers are beginning to turn their
attention to this long-neglected group. For example, in 1999, the
National Institutes of Health launched a major research effort that
will attempt to answer some of the many questions that remain. The
seven-year, multi-site study will follow more than 5,000 men ages
65 and older to determine how much the risk of fracture in men is
related to bone mass and structure, biochemistry, lifestyle, tendency
to fall, and other factors.
The results of such studies will help physicians better understand
how to prevent, manage and treat osteoporosis in men. But much is
already known. This fact sheet answers some of the fundamental questions.
What Causes Osteoporosis?
Bone is constantly changing - that is, old bone is removed and
replaced by new bone. During childhood, more bone is produced than
removed, so the skeleton grows in both size and strength. The amount
of tissue or bone mass in the skeleton reaches its maximum amount
by the late twenties. By this age, men typically have accumulated
more bone mass than women. After this point, the amount of bone
in the skeleton typically begins to decline slowly as removal of
old bone exceeds formation of new bone.
In their fifties, men do not experience the rapid loss of bone
mass that women have in the years following menopause. By age 65
or 70, however, men and women lose bone mass at the same rate, and
the absorption of calcium, an essential nutrient for bone health
throughout life, decreases in both sexes.
Once bone is lost, it cannot be replaced. Excessive bone loss causes
bone to become fragile and more likely to fracture. This condition,
known as osteoporosis, is called a "silent disease" because
it progresses without symptoms until a fracture occurs.
Fractures resulting from osteoporosis most commonly occur in the
hip, spine, and wrist and can be permanently disabling. Hip fractures
are especially likely to be disabling. Perhaps because such fractures
tend to occur at older ages in men than in women, men who sustain
hip fractures are more likely to die from complications than are
women. More than half of all men who suffer a hip fracture are discharged
to a nursing home, and 79 percent of those who survive for one year
after a hip fracture still live in nursing homes or intermediate
care facilities.
Primary and Secondary Osteoporosis
There are two main types of osteoporosis: primary and secondary.
In cases of primary osteoporosis, the condition is either caused
by age-related bone loss (sometimes called senile osteoporosis)
or the cause is unknown (idiopathic osteoporosis). The term idiopathic
osteoporosis is used only for men less than 70 years old; in older
men, age-related bone loss is assumed to be the cause.
At least half of men with osteoporosis have at least one (sometimes
more than one) secondary cause. In cases of secondary osteoporosis,
the loss of bone mass is caused by certain lifestyle behaviors,
diseases or medications. The most common causes of secondary osteoporosis
in men include exposure to glucocorticoid medication, hypogonadism
(low levels of testosterone), alcohol abuse, smoking, gastrointestinal
disease, hypercalciuria and immobilization.
Causes of Secondary Osteoporosis in Men
Glucocorticoid excess
Other immunosuppressive drugs
Hypogonadism
Alcohol excess
Smoking
Chronic obstructive pulmonary disease and asthma
Cystic fibrosis
Gastrointestinal disease
Hypercalciuria
Anticonvulsant medications
Thyrotoxicosis
Hyperparathyroidism
Immobilization
Osteogenesis imperfecta
Homocystinuria
Neoplastic disease
Ankylosing spondylitis and rheumatoid arthritis
Systemic mastocytosis
Glucocorticoid excess
Glucocorticoids are steroid medications used to treat diseases
such as asthma and rheumatoid arthritis. Bone loss is a very common
side effect of these medications. In fact, exposure to glucocorticoids
accounts for 16-18 percent of osteoporosis in men. The damage these
medications cause may be due to their direct effect on bone, muscle
weakness or immobility, reduced intestinal absorption of calcium,
a decrease in testosterone levels or, most likely, a combination
of these factors.
Bone mass often decreases quickly and continuously with ongoing
use of glucocorticoid medications, with most of the bone loss in
the ribs and vertebrae. About one-third of patients have evidence
of vertebral fractures after 5 to 10 years of treatment with glucocorticoids.
The risk of hip fracture is increased nearly three-fold. Therefore,
patients taking these medications should talk to their doctor about
having a bone mineral density (BMD) test; men should also be tested
to monitor testosterone levels, as glucocorticoids often reduce
testosterone in the blood.
A treatment plan to minimize damage to bone during long-term glucocorticoid
therapy may include using the minimal effective dose, discontinuation
of the drug when practical, and topical (skin) administration if
possible. Adequate calcium and vitamin D nutrition is important,
as these nutrients help reduce the impact of glucocorticoids on
bone. Other possible treatments include testosterone replacement
and medication. Alendronate and risedronate are two bisphosphonate
medications approved by the U.S. Food and Drug Administration for
use by men and women with glucocorticoid-induced osteoporosis.
Hypogonadism
Hypogonadism refers to abnormally low levels of sex hormones. It
is well known that loss of estrogen causes osteoporosis in women.
In men, reduced levels of the sex hormones may also cause osteoporosis.
In fact, it is estimated that up to 30 percent of men with osteoporotic
vertebral fractures have low testosterone levels. While it is natural
for testosterone levels to decrease with age, there should not be
a sudden drop in this hormone comparable to the drop in estrogen
experienced by women at menopause. However, medications like steroids
(discussed above), cancer treatments (especially for prostate cancer),
and many other factors can affect testosterone levels.
Testosterone replacement therapy may be helpful in preventing or
slowing bone loss. Its success depends on factors such as age and
how long testosterone levels have been reduced. Also, it is not
yet clear how long any beneficial effect of testosterone replacement
will last; therefore, doctors will usually treat the osteoporosis
directly, using medications approved for this purpose.
Recent research suggests that estrogen deficiency may be a cause
of osteoporosis in men. For example, estrogen levels are low in
men with hypogonadism and may play a part in bone loss. Osteoporosis
has been found in some men who have rare disorders of estrogen action.
Therefore, the role of estrogen in men is under active investigation.
Alcohol abuse
There is a wealth of evidence that alcohol abuse may decrease bone
density and lead to an increase in fractures. Low bone mass is found
in 25 to 50 percent of men who seek medical help for alcohol abuse.
One early study found the bone mass of young alcoholic males to
be comparable to that of elderly females.
In cases where bone loss is linked to alcohol abuse, the first
goal of treatment is, of course, to help the patient stop--or at
least reduce--his consumption of alcohol. More research is needed
to determine whether bone lost to alcohol abuse will rebuild once
drinking stops, or even whether further damage will be prevented.
It is clear, though, that alcohol abuse causes many other health
and social problems, so quitting is ideal. A treatment plan may
also include a diet with lots of calcium- and vitamin D-rich foods,
calcium supplementation, and physical exercise, and would discourage
smoking.
Smoking
Bone loss is more rapid, and rates of hip and vertebral fracture
are higher, among men who smoke, although more research is needed
to determine exactly how smoking damages bone. Tobacco, nicotine
and other chemicals found in cigarettes may be directly toxic to
bone or they may inhibit absorption of calcium and other nutrients
needed for bone health. Quitting is the ideal approach, of course,
as smoking is harmful in so many ways. But again, as with alcohol,
it is not known whether quitting smoking leads to reduced rates
of bone loss or to a gain in bone mass.
Gastrointestinal disorders
Several nutrients, including amino acids, calcium, magnesium, phosphorous
and vitamins D and K are important for bone health. Diseases of
the stomach and intestines can lead to bone disease when they impair
absorption of these nutrients. Treatment for bone loss in this case
may include supplementation of the poorly absorbed nutrient(s).
Hypercalciuria
Hypercalciuria is a disorder that causes too much calcium to be
lost through the urine, which makes the calcium unavailable for
building bone. It is more than twice as common in men as in women.
Patients with hypercalciuria should talk to their doctor about having
a BMD test and, if bone density is low, discuss treatment options.
Immobilization
Weight-bearing exercise is essential for maintaining healthy bones;
without it, bone density may rapidly decline. Prolonged bed rest
(following fractures, surgery, spinal cord injuries or illness)
or immobilization of some part of the body often results in significant
bone loss. It is crucial to resume weight-bearing exercise (such
as walking, jogging, dancing and weight-lifting) as soon as possible
after a period of prolonged bed rest. If this is not possible, patients
should work with their doctor to minimize other risk factors for
osteoporosis.
What Are the Risk Factors for Men?
Several risk factors have been linked to osteoporosis in men:
Chronic diseases that affect the kidneys, lungs, stomach, and intestines
or alter hormone levels.
Undiagnosed low levels of the sex hormone testosterone.
Unhealthy lifestyle habits (e.g., smoking, excessive alcohol use,
low calcium intake, inadequate physical exercise).
Age: The older you are, the greater your risk.
Heredity: A son is almost four times as likely to have low bone
mineral density (BMD) if his father has low BMD, and nearly 8 times
as likely if both parents have low BMD.
Race: Caucasian men appear to be at particularly high risk, but
all men can develop this disease.
How Is Osteoporosis Diagnosed in Men?
Osteoporosis can be effectively treated if it is detected before
significant bone loss has occurred. A medical work-up to diagnose
osteoporosis will include a complete medical history, x-rays, and
urine and blood tests. The doctor may also order a BMD test or bone
mass measurement. A special type of x-ray, the BMD test requires
trace amounts of radiation. It is safe, accurate, quick, painless,
and noninvasive and can be used to detect low bone density, predict
risk for future fractures, diagnose osteoporosis and monitor the
effectiveness of treatments.
It is increasingly common for women to be diagnosed with osteoporosis
or low bone mass using a BMD test, often at mid-life when doctors
begin to watch for signs of bone loss. In men, however, the diagnosis
is often not made until the patient sees his doctor complaining
of back pain or until a fracture occurs. This makes it especially
important for men to inform their doctor about risk factors for
developing osteoporosis, loss of height or change in posture, a
fracture, or sudden back pain.
Some doctors may be unsure how to interpret the results of a BMD
test in male patients. For example, it is not known whether the
guidelines used to diagnose osteoporosis or low bone mass in women
(developed by the World Health Organization) are also appropriate
for men. Until that question is answered--and until separate criteria
are established for men, if necessary--most experts suggest using
the WHO criteria for men.
What Treatments Are Available?
Once a man has been diagnosed with osteoporosis, his doctor may
prescribe one of the medications approved by the Food and Drug Administration
(FDA) for this disease. Alendronate has been approved for the treatment
of the disease in men. Alendronate and risedronate are approved
for the treatment of glucocorticoid induced osteoporosis in both
men and women.
The treatment plan will also likely include the nutrition, exercise,
and lifestyle guidelines for preventing bone loss listed at the
end of this fact sheet.
If bone loss is due to glucocorticoid use, the doctor may monitor
bone density and testosterone levels and may suggest using the minimal
effective dose of glucocorticoid, discontinuing the drug when practical,
and/or topical (skin) administration. Other possible prevention
or treatment approaches include calcium and/or vitamin D supplementation,
testosterone replacement, and osteoporosis treatment medications
such as bisphosphonates.
If osteoporosis is the result of another condition (such as testosterone
deficiency) or exposure to certain medications, the doctor may design
a treatment plan to address the underlying cause.
New Treatment Approved for Men with Osteoporosis
On September 29, 2000, the U.S. Food and Drug Administration (FDA)
approved alendronate sodium for treatment to increase bone mass
in men with osteoporosis. This is the first medication to be indicated
for men with osteoporosis.
The efficacy of alendronate sodium (at the recommended dosage of
10 mg once daily) for building bone mineral density in men with
osteoporosis was demonstrated in a two-year study of men between
the ages of 31 and 87. After two years, significant increases in
bone density were found in the spine, hip, and total body of the
men treated with alendronate. Treatment also reduced the risk of
vertebral fractures and reduced height loss.
How Can Osteoporosis Be Prevented?
There have been fewer research studies on osteoporosis in men than
in women. However, experts agree that all people should take the
following steps to preserve their bone health.
Avoid smoking, reduce alcohol intake, and increase level of activity.
Ensure a daily calcium intake that is adequate for your age.
Ensure an adequate vitamin D intake. Normally, the body makes enough
vitamin D from exposure to as little as 10 minutes of sunlight a
day. If exposure to sunlight is inadequate, dietary vitamin D intake
should be at least 400 IU but not more than 800 IU/day; 400 IU is
the amount found in one quart of fortified milk and most multivitamins.
Engage in a regular regimen of weight-bearing exercises where bones
and muscles work against gravity. This includes walking, jogging,
racquet sports, stair climbing, team sports, lifting weights, and
using resistance machines. A doctor should evaluate the exercise
program of anyone already diagnosed with osteoporosis to determine
if twisting motions and impact activities, such as those used in
golf, tennis, or basketball, need to be curtailed.
Discuss with the doctor the use of medications, such as steroids,
that are known to cause bone loss.
Recognize and treat any underlying medical conditions that affect
bone health.
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