[In men, testosterone levels normally begin a gradual decline after the age of 30. The average levels for most men range from 300 to 1,000 nanograms per deciliter of blood. But testosterone levels can fluctuate so greatly depending on so many factors — sleep, the time of day, medication — that many men who fall into the hypogonadal range one day will have normal levels the next.]
The number of middle-aged men with prescriptions for testosterone is
climbing rapidly, raising concerns that increasing numbers of men are abusing
the powerful hormone to boost their libidos and feel younger, researchers
reported on Monday.
Testosterone replacement therapy is approved specifically for the
treatment of abnormally low testosterone levels, a condition called hypogonadism. The hormone helps build muscle,
reduce body fat and improve sex drive. But a study published in the journal
JAMA Internal Medicine found that many men who get prescriptions for the
hormone have no evidence of a deficiency at all.
The new study is the largest of testosterone prescribing patterns to
date, involving nearly 11 million men who were tracked through a large health
insurer. The report showed that the number of older and middle-aged men
prescribed the hormone has tripled since 2001.
Men in their 40s represent the fastest-growing group of users. About
half of men prescribed testosterone had a diagnosis of hypogonadism, and
roughly 40 percent had erectile or sexual dysfunction. One third had a
diagnosis of fatigue.
The medical group that sets clinical guidelines for testosterone
replacement therapy, the Endocrine Society,
recommends treatment only in men who have unequivocally low testosterone
levels. That finding requires a blood test. But the new report found that a
quarter of men did not have their levels tested before they received the
hormone. It was also unclear what proportion of men who did undergo testing
actually had results showing a deficiency.
Testosterone therapy can cause thickening of the blood, acne and
reduced sperm counts. Many doctors worry that it also raises the risk of heart
disease and prostate cancer, though some experts say that
those concerns are unproved. Jacques Baillargeon, the lead author of the
new research, said that the safety of long-term testosterone use had yet to be
established in good studies.
“I think these relatively healthy men who are starting testosterone at
age 40 are potentially going to be exposed for a very long time, and we don’t
know what the risks are,” said Dr. Baillargeon, an associate professor of
epidemiology at the University of Texas Medical Branch at Galveston.
In men, testosterone levels normally begin a gradual decline after the
age of 30. The average levels for most men range from 300 to 1,000 nanograms
per deciliter of blood. But testosterone levels can fluctuate so greatly
depending on so many factors — sleep, the time of day, medication — that many
men who fall into the hypogonadal range one day will have normal levels the
next.
Some studies estimate that up to 30 percent of men ages 40 to 79 have
a true deficiency, though only a small percentage actually develop clinical
symptoms like depression, hot flashes and erectile dysfunction.
Dr. Ronald S. Swerdloff, an endocrinologist at
the University of California, Los Angeles, and an author of the Endocrine
Society’s treatment guidelines, said the recommendations were “quite clear”
that treatment is for men who have had blood tests showing a testosterone
deficiency, as well as symptoms consistent with the disorder. “I don’t think
it’s appropriate for patients to be treated for hypogonadism without chemical
evidence to support it,” he said.
Dr. Abraham Morgentaler, a professor of urology at Harvard Medical
School and the author of “Testosterone for Life,” said the findings were
a good sign that more testosterone deficiencies were being diagnosed and
treated. While many doctors worry about the side effects of testosterone abuse,
he said, there are also studies showing that men with low testosterone levels
have shorter life spans and an increased risk of diabetes, heart disease and osteoporosis.
“Aging is associated with bad vision, bad hearing, bad teeth, bad
arteries, bad joints and cancer, and we treat all of these things,” Dr.
Morgentaler said. “I think it’s an unfair stretch to say that because something
is common or natural that we shouldn’t treat it.”
SLATHERING ON SUNSCREEN SHOWS RESULTS
[People with fair skin have much more of a problem with photo-aging and skin cancer than those with darker skin, Dr. Gilchrest said. But if asked to speculate about whether darker-skinned people would retain more youthful skin if they used sunscreen, she said she thought they would.]
People who
diligently use sunscreen every day can slow or even prevent for a time the
development of wrinkles and sagging skin, a new study found. Although
dermatologists have long told people to use sunscreen to prevent aging, this is
the first research to show an actual effect on the appearance of skin,
researchers said.
The study
involved 900 white people ages 25 to 55 in Australia, where intense sun
exposure is a fact of life. Most had fair skin, and nearly all burned in the
sun. Most were using sunscreen at least some of the time, and two-thirds wore
hats in the sun.
But
researchers wanted to find out what would happen to skin if people tried to use
a broad-spectrum sunscreen all the time over four and a half years. Half of the
study participants were told to continue their usual practices, and the other
half to slather on sunscreen daily.
The result, the researchers reported on Monday in The Annals of Internal Medicine, is
that those assigned to use sunscreen every day had noticeably more resilient
and smoother skin than those assigned to continue their usual practices.
The study also
included nearly 900 people who were randomly assigned to take beta carotene, a
nutritional supplement, or a placebo to see if the supplement prevented skin
aging. It did not.
The sunscreen
element of the study impressed other researchers. Dr. David R. Bickers, a
dermatology professor at Columbia University who was not involved in the research,
said it “makes it clear that extensive, consistent use of sunscreen can alter a
pattern of what would be an inevitable progression of photo-aging.”
Until now, he
said, most studies of sun-damaged skin were conducted with mice, not people,
and it was not clear whether the results would be the same.
Dr. Barbara A.
Gilchrest, a dermatology professor at the Boston University School of Medicine
and the editor of The Journal of Investigative Dermatology, said she, too,
found the study convincing.
Dr. Gilchrest,
who was not associated with the study, noted that its subjects were not
inveterate tanners but rather people who tried to protect their skin.
“They were not
taking the worst sun offenders and taking them out of the sun,” Dr. Gilchrest
said. “Everyone had pretty darn good sun-protection habits to begin with.”
No one had
done such a study before because the very idea is daunting, dermatologists
said. Hundreds of healthy people had to agree to follow their assigned regimens
for years.
The sunscreen
used by those assigned to daily applications had a sun protection factor, or
SPF, of 15, which filters 92 percent of the sun’s rays. Someone who would
normally burn in 10 minutes would burn in 150 minutes with an SPF 15. Those
assigned to use sunscreen even had their sunscreen bottles weighed to make sure
they were using it.
“Getting
compliance over a sustained period of time is no mean feat,” Dr. Bickers said.
“To me, it is remarkable that they were able to get the degree of compliance
that they did.”
The sunscreen
study was paid for by the National Health and Medical Research Council of
Australia. No sunscreen makers contributed.
Researchers
studied only white people in Nambour, northeast of Sydney. Participants agreed
to let researchers make silicone casts of their skin at the start and the end
of the study to assess how their skin had aged.
The study’s
principal investigator, Adele C. Green, a senior scientist at the Queensland
Institute of Medical Research and her colleagues there and at the University of
Queensland had previously shown that this method provides the same sort of
information as a skin biopsy. With a biopsy, dermatologists look at elastin,
the elastic tissue, which degrades with aging, contributing to wrinkles and
sagging skin.
It is easy to
see the effects of aging in a biopsy, said Dr. David J. Leffell, a professor of
dermatology and surgery at Yale. “Instead of nice pink fibers, you see a purple
amorphous material. It is almost like looking at a photograph through a lens
covered with Vaseline.”
The silicone
molds allowed experts to look at corresponding changes on the skin’s surface.
In making a mold, a subject first stretched the skin on the top of a hand by
grasping a cardboard tube and making a fist. Then a researcher covered the top
of the hand with silicone and peeled it off, forming the mold.
Assessors, who
did not know whether the subjects were using sunscreen, examined the lines in
the silicone molds and graded them from 0 to 6.
A score of 0
means no photo-aging at all. “It’s like a baby’s skin, resilient,” Dr. Green
said. “There is a fine network of lines under a microscope.”
A person with
a score of 6 has severely aged skin, with no elasticity and deep lines. Every
point on the scale represents coarser skin and increased wrinkling on the hand,
the face or wherever the skin is being assessed. On the face, each point is
also associated with a greater number of visible small blood vessels.
At the start
of the study, the median score in both groups of subjects was 4, which means
they had moderate photo-aging. At the end, those assigned to daily sunscreen
use still had a median score of 4, but those in the control group had a median
of 5.
The study does
not answer the question of whether people older than 55 would also have more
youthful skin if they used sunscreen, Dr. Green cautioned. After 55, she said,
aging’s effects on skin start to predominate. And the effects of ultraviolet
light on skin are cumulative.
It is not
known how much sunscreen can help if its use is started later in life. But Dr.
Green would advise it anyway, she said, because it can protect against skin
cancer.
The study also
does not answer the question of whether darker-skinned people could protect
their skin from wrinkling and sagging by using sunscreen.
People with
fair skin have much more of a problem with photo-aging and skin cancer than
those with darker skin, Dr. Gilchrest said. But if asked to speculate about
whether darker-skinned people would retain more youthful skin if they used
sunscreen, she said she thought they would.
It is not
clear that anyone will ever get an answer for darker-skinned people, though,
said Dr. Robert A. Swerlik, a dermatology professor at Emory University. With
less photo-aging in darker skin, it would take longer to see an effect, if
there was one, he noted.
“If the study
could be extended long enough and people could be enticed to use screening
agents diligently, an effect likely could be shown in darker-skinned people,”
Dr. Swerlik said. But, he added, “whether it is worth the effort to religiously
apply sunscreen over many years when your personal probability of benefit is
uncertain and perhaps low is another story.”
