Sunday,
Apr. 20, 2003
Ask American women what disease they're most scared of,
and the vast majority will answer without hesitation: breast
cancer. They may even cite the ominous statistic that 1 in
8 women will develop breast cancer at some point in her life.
But what most women don't realize is that they actually have
far more to fear from heart disease, which will strike 1
out of every 3. More than 500,000 women die in the U.S. each
year of cardiovascular disease, making it, not breast cancer
(40,000 deaths annually), their No. 1 killer.
Women and heart disease? Better believe it. For while most
people still think of cardiovascular trouble as mainly a
man's problem, the reality is that heart disease has never
discriminated between the sexes. In fact, for a variety of
complex reasons, the condition is more often fatal in women
than in men and is more likely to leave women severely disabled
by a stroke or congestive heart failure. True, women don't
usually start showing signs until their 60s — about
10 years after men first develop symptoms. And hormones seem
to play a protective role in women before menopause. But
the common belief that premenopausal women are immune to
heart problems is just plain wrong. Heart attacks strike
9,000 women younger than 45 each year.
The more scientists learn about a woman's heart and what
can go wrong with it, the more they realize that females
aren't just small males. There are subtle but important differences
in how women's cardiovascular systems respond to stress,
hormones, excess saturated fat and toxins like tobacco. There
are also some pretty big differences in how aggressively
doctors treat women with heart trouble — even in the
emergency room when they are in most desperate need of help.
All those publicity campaigns that have focused attention
on breast cancer may be part of the problem. The pink ribbons,
the docudramas and the races for a cure have inadvertently
left women with the impression that breast cancer is the
only thing they need be worried about. So when public-health
officials at the National Heart, Lung and Blood Institute
(NHLBI) decided to spread the word about women's risk of
heart disease with a campaign called Heart Truth, they took
a page from the cancer advocates' manual, designed their
own lapel pin — in the shape of a bright red dress — and
sought help from some very highly placed women, starting
with the First Lady. "Women take care of all the people
in their family — their children, their husbands — but
they sometimes don't take care of themselves," says
Laura Bush. "The goals of this campaign are just to
really make sure that women know that heart disease is their
No. 1 killer and that they can change their lifestyles to
prevent it."
The new push couldn't come at a more critical juncture. Many
women were stunned last year when the famous Women's Health
Initiative discovered that pills providing a combination
of estrogen and progestin do not protect the hearts of postmenopausal
women. (Tests on estrogen alone are still under way.) Suddenly,
what had seemed to be the simplest, most elegant solution
to the aging female heart — replacing the hormones
a woman makes before menopause — had vanished.
After that bombshell, doctors and their female patients had
a lot of questions. If hormones don't prevent heart disease,
what does? Is the ailment fundamentally different in men
and women? If not, why do their symptoms seem to differ?
And why do treatments such as bypass surgery and angioplasty,
which work so well for men, often fail for women? In some
ways, says Dr. Sharonne Hayes of the Mayo Clinic in Rochester,
Minn., "the findings have allowed us appropriately,
and perhaps belatedly, to refocus our efforts."
It's not as if doctors were starting from scratch. Cholesterol-lowering
drugs like statins and antihypertensive medications like
beta-blockers clearly help both men and women, as do a healthy
diet and plenty of exercise. "The vast majority of heart
attacks in women could be prevented with a combination of
lifestyle modifications and medication," says Dr. JoAnn
Manson at the Brigham and Women's Hospital in Boston. "Just
making use of existing information could nearly eradicate
the disease."
At the top of the list of risk factors that men and women
share is smoking, the most dangerous killer for both sexes,
followed by diabetes, high blood pressure, high cholesterol
levels, excess weight and physical inactivity. Some factors,
however, seem to affect women more severely than men. In
fact, smoking and diabetes completely counteract whatever
protective benefits a woman normally enjoys before menopause.
Also, women are more likely to be overweight, less likely
to exercise and appear to be affected more adversely by stress.
Of course, neither men nor women can do anything about their
age or the genes they were born with. (If your father had
a heart attack before 55 or your mother had a heart attack
before 65, you should pay special attention to your heart
health.) And it's still unclear why heart disease seems to
strike men and women so differently. Structurally, their
hearts and arteries are basically the same; women's hearts
are smaller, but in proportion to their bodies. So doctors
are pretty sure that any differences are matters of degree
rather than kind.
Cardiologists are confident that they understand how heart
attacks occur in men. The trouble usually begins when a fatty
deposit or plaque, which has taken decades to build up on
the inside of a coronary artery, becomes unstable and bursts,
triggering a clot that blocks a blood vessel. Doctors can
see these plaques during a fairly invasive procedure called
an angiogram, in which a catheter is threaded through an
artery in the groin or leg up to the arteries of the heart
and a dye is then released to make any blockages easier to
spot.
Although the research is controversial, some evidence suggests
that bursting plaques may not be as important for women as
for men. Doctors have long puzzled over the fact that some
of their female heart-attack patients — usually those
who have not yet gone through menopause — show few
signs of artery-clogging plaques on their angiograms. Perhaps
their
blockages don't occur in the major arteries of the heart,
where angiograms are performed and bypasses are most effective.
Perhaps blood flow is restricted in the smaller vessels that
branch off the coronary arteries. And perhaps the problem
isn't plaques at all but the fact that these smaller blood
vessels are somehow more prone to spasm, snapping shut at
the slightest stress or trigger, cutting off the flow of
blood to parts of the heart.
Indirect evidence of just such a possibility was published
by researchers at the University of Wisconsin-Madison in
the Journal of the American Medical Association last year.
By looking at high-resolution images of the blood vessels
of the retina — one of the few places where doctors
can easily examine the body's vascular system without an
invasive
test — they found that women with the narrowest arteries
were most likely to have heart disease but that the size
of the blood vessels made no difference in men. The small-vessel
theory has some flaws. For example, certain drugs called
vasodilators, which act to keep blood vessels open, do not
appear to prevent heart attacks in women, as you would expect
if spasms were the primary problem. Still, there are enough
other ways in which small vessels may be involved that researchers
aren't yet ready to dismiss their role.
It's also possible that plaques — whether in the main
coronary arteries or the smaller vessels — behave differently
in women. Unlike men, women tend to distribute all the "garbage" associated
with atherosclerosis — such as saturated fat and oxidized
waste products — more evenly throughout the arteries.
The process is analogous to the way men and women gain weight,
says Dr. Noel Bairey Merz of the Cedars-Sinai Medical Center
in Los Angeles. "When men get fat, it all goes to their
belly," she says. "When women get fat, they tend
to get fat all over — fat at the ankles, fat in the
sides, fat in the upper arms." So although women generally
avoid the monster plaques that kill so many men in early
middle age, the continuing buildup in women's arteries may
come back to haunt them in their 50s, 60s, 70s and 80s.
Plaques are another reason for women to throw away their
cigarettes, as smoking seems to turn stable plaques into
unstable ones. "If you look at the plaque (of a woman)
under a microscope, it doesn't appear to be the kind of plaque
that can become unstable and rupture," says Dr. Robert
Bonow of the American Heart Association. "But the surface
has become eroded, exposing the material beneath the surface
to the blood, which causes blood clots. And it turns out
that the women who have this plaque erosion tend to be women
who smoked." Those clots can travel through the bloodstream,
wreaking havoc in the heart or the brain.
Getting to the bottom of why men and women report different
cardiac symptoms is trickier than might be expected. In fact,
some researchers think the differences can be emphasized
too much. If a woman doesn't think she can have heart disease,
notes Dr. George Sopko of the NHLBI, she's not going to interpret
her symptoms as heart disease — even if her symptoms
are the same as a man's. Truth is, the classic heart attack
made famous onstage and onscreen, where you clutch your chest
and fall to the ground, doesn't tell the whole story. "Half
the time women don't do that," says Cedars-Sinai's Bairey
Merz. "But 40% of the time, men don't have a typical
heart attack either." Men, however, have been conditioned
for decades to suspect that they might be suffering a heart
attack even when they feel perfectly healthy. So while women
are more likely to experience the prelude to an attack as
shortness of breath, extreme fatigue or a feeling that they
have a bad case of indigestion, they often can't believe
that their symptoms are cardiac in origin. Equally important,
their doctors often don't believe it either. Doctors tend
to put off ordering necessary tests for women having a heart
attack or fail to treat them aggressively enough.
Just ask Kathy Kastan, 43, a psychotherapist in Memphis,
Tenn., who suffered both classic and less common symptoms. "I
noticed that I would get tired more quickly," says Kastan,
who was and still is very active — biking, swimming,
running, walking. "I would sometimes have to stop because
I had shortness of breath." After a couple of trips
to the doctor, who failed to pick up on her heart problems,
she collapsed in the street while on a vacation in Colorado. "I
clutched my chest, had profuse sweating, chest pains from
the front to the back, down my arm, up into my jaw." When
the symptoms went away, she attributed them to the altitude.
Finally, after collapsing one more time, she underwent a
more comprehensive and rigorous stress test, which revealed
a blockage that required bypass surgery after earlier treatments
ended in failure. Now when Kastan talks to women's groups
about heart disease, she tells them they need to know their
risks and insist that doctors take them seriously.
To be fair, denial isn't the only thing working against women. "More
than men, women have stress-related chest pain and pain when
they are resting," says Dr. Randolph Martin of the Emory
University School of Medicine in Atlanta. Sometimes the pain
results from sore chest muscles or monthly variations in
a woman's sensitivity.
Also, women frequently have abnormal ECG readings during
the classic treadmill test even when their hearts are functioning
normally. But before you decide that treadmill tests are
worthless, consider the latest research from the wise study,
short for Women's Ischemic Syndrome Evaluation. Data from
wise suggest that false positives in women may be not so
much an error as an early warning of a problem, perhaps in
the smaller blood vessels, that could become significant
in 20 to 30 years, according to Bairey Merz.
To get a better handle on what's going on inside a woman's
heart, many cardiologists perform an echocardiogram during
a treadmill test. Echocardiograms can give doctors a detailed
picture of the size, shape and pumping action of the chambers
of the heart and of how well the valves are working. If the
pumping action looks stiff, doctors know the heart is ailing.
Even cholesterol testing is less straightforward in women
than in men. Whereas high levels of ldl, the so-called bad
cholesterol, are pretty good at identifying men at high risk
of heart disease, women seem more vulnerable to high levels
of a different fatty substance, called triglycerides. In
addition, women with low levels of HDL, the so-called good
cholesterol, are more likely than men to develop heart disease
later on. National guidelines suggest a minimum HDL level
of 40 mg/dL for men and women. "But (low) HDL is a more
powerful predictor of risk in women," says Dr. Lori
Mosca of New York-Presbyterian Hospital. "So in my practice
I recommend keeping an HDL of 50 mg/dL for women."
Add up all the caveats and uncertainties, and it's not surprising
that when women finally get to the hospital, it takes longer
for doctors and nurses to diagnose their trouble correctly.
Unfortunately, the delay may make female patients too sick
to qualify for certain lifesaving treatments, such as clot-buster
drugs that can stop a heart attack in its tracks. And because
most women are older when they develop heart trouble, they
are more likely to suffer from other conditions that complicate
their care.
Fortunately, the medical community is starting to adapt to
the new realities of women and heart disease. Two studies
suggest that women may finally be benefiting as much as men
from angioplasty, a procedure in which doctors use catheters
and balloons to open up dangerously narrowed arteries and
insert stents to keep the arteries open. In the past, catheters
and stents were all made in one standard size — to
fit men's larger arteries. As a result, women suffered more
complications
and a much higher risk of death from angioplasty. Also, until
about three years ago doctors prescribed the same doses of
the blood thinner heparin for men and women, leading to greater
internal bleeding in women. Smaller catheters and stents
and lower doses should give women better results.
There's plenty that women — and men — can do
to help protect themselves. There are no guarantees, but
adopting
a healthier lifestyle, which includes eating right, getting
more exercise and quitting smoking, will tip the odds in
their favor. Probably the hardest thing for women to overcome,
however, is the false sense of security given by the premenopausal
years, which to some degree help delay the start of heart
disease about 10 years. Many men would love to have an extra
10 years in which to make positive changes in their lifestyles.
Women who fail to take advantage of this gift do so at their
heart's peril.
Reported
by David Bjerklie, Alice Park and Sora Song / New York
Copyright © 2003
Time Inc.
