Daily Aspirin for Men Only?
Aspirin Cuts Risk of First Heart Attack in Men but Not in Women
Oct. 18, 2007 - Aspirin cuts the risk of a first heart attack in men but not
in women, an analysis of clinical trial data suggests.
Don D. Sin, MD, and colleagues at the University of British Columbia,
Vancouver, Canada, looked at data from clinical trials of aspirin for the
prevention of heart attack.
The evidence suggests that aspirin helps everyone who has had a heart
attack. But when it came to preventing a first heart attack, different trials
got different results.
Why? Studies that looked predominantly at men found that aspirin helped.
Trials that looked predominantly at women found no effect.
"Our report suggests an aspirin a day reduces a man's risk of a first
heart attack by 25%. In women there seems to be no effect," Sin tells
WebMD. "This is true only for women with no risk factors who haven't had
heart attacks in the past. People who have had heart attacks should take an
aspirin a day, regardless of whether they are male or female."
Aspirin Different in Women
It's not the first study to find that
aspirin has different benefits for women than it does for men. Researchers
are learning that some people are resistant to aspirin's blood-thinning
effects. And those people tend to be women, says Alan Heldman, MD, clinical
chief of cardiology at University of Miami Miller School of Medicine.
"In several studies, the frequency of being aspirin resistant seemed to
be higher among women than among men," Heldman tells WebMD. "Why would
that be so? Women with heart disease are typically older than men with heart
disease. That obviously has an impact on all sorts of other variables about the
patient's response to treatment."
Laurence S. Sperling, MD, director of the Emory Heart Center risk reduction
program, says it's not yet clear that aspirin resistance is the main reason
women respond differently to aspirin than men do.
"As much as 40% of the population may have aspirin resistance. It may be
that this waxes and wanes over the course of a patient's life. But there are
suggestions it is more common in women," Sperling tells WebMD.
Sperling notes that the benefits of daily aspirin seem to differ between men
"The data suggest aspirin offers more of a stroke-prevention effect in
women rather than the heart-attack prevention effect seen in men," he says.
"Still, I don't withhold aspirin as a preventive strategy in a high-risk
female -- someone with diabetes, for example."
Heldman and Sin wholeheartedly agree that some women definitely benefit from
preventive treatment with aspirin.
For patients with multiple risk factors for heart disease -- such as those
who smoke and those with high cholesterol or diabetes -- I would probably put
them on aspirin even if they haven't yet had a coronary event," Heldman
says. "And I use aspirin for both men and women in that regard, although we
keep our eye on the notion it may be less effective for women."
The bottom line, says Sin, is that nobody should take aspirin before talking
with a doctor.
"This study is a sobering reminder to the public that before
self-medicating, be sure to consult your doctor to learn whether the medicine
you are about to take is right," Sin says. "And this is especially true
for women and aspirin."