Reprinted from the Health District's quarterly publication mailed to district residents (Spring 2006)

An aspirin-a-day may keep a stroke or heart attack away. But simply popping the century-old, over-the-counter pain reliever on a daily basis without first talking with your doctor may bring unexpected complications for some people.

How could one baby aspirin a day be so powerful in preventing heart problems yet put a small number of adults at risk for serious side effects such as bleeding?

The answer lies in understanding how aspirin works. Picture a teeter-totter, with aspirin’s truckload of heart-friendly benefits stacked on one end and a handful of risks on the other.

What’s good about it

It’s been known for years that aspirin can relieve pain, lower fever and reduce inflammation. Unlike ibuprofen and other nonsteroidal anti-inflammatory drugs (NSAIDs), aspirin also can protect the heart from blood clots. Think for a moment what happens when you cut yourself: Platelets in the blood clump together to form a clot, which stops the bleeding.

Take an aspirin, and those platelets become less sticky, making it harder for blood to clot.

That can be a good thing when you’re talking about keeping blood vessels to the heart and brain free of clots. It’s even better news given that more than 1 million Americans each year experience a first or repeat heart attack or fatal coronary heart disease.

Aspirin’s benefits are well established and impressive. Studies have shown that taking a low dose of aspirin (81 mg) either daily or every other day reduced the risk of coronary heart disease by 28 percent in people who had never had a heart attack or stroke but were at increased risk for one.

What increases a person’s risk for heart disease? Age, gender, diabetes, high level of LDL (bad cholesterol), low level of HDL (or good cholesterol), elevated blood pressure, family history of premature heart disease and smoking are factors. These people stand to benefit the most from aspirin therapy.

Aspirin has, for some time, been on the protocol for heart patients. “Virtually everyone with coronary disease is on it unless there’s some compelling reason not to be, such as serious bleeding risk or allergy,” says Dr. Todd Whitsitt, a cardiologist at Heart Center of the Rockies.

Consider the risks

But it’s the bleeding risk and allergy where the aspirin teeter-totter starts to tip a bit.

“The risk for bleeding is real, but not particularly high,” Dr. Whitsitt says.

Risk for major bleeding from irritation to the esophagus or stomach is estimated at 2-4 per 1,000 people over 5 years for those at risk for heart disease.

Aspirin also presents a smaller risk (0-2 per 1,000 people over 5 years) for a type of stroke caused not by clots but a ruptured blood vessel in the brain.

“People need to have a discussion with their primary-care physician to balance the risks vs. benefits of taking aspirin regularly,” says Dr. Bruce Cooper, medical director at the Health District.

“It’s a complicated equation. It’s not just weighing your cardiovascular risk but looking at the side effects of taking aspirin, which include bleeding and possible interactions with other medications you take.”

People who take blood thinner medications, have a history of bleeding ulcers or take high doses of other nonsteroidal anti-inflammatory drugs may be at higher risk for bleeding, doctors say, and are not good candidates for aspirin therapy.

About 1 percent of adults in the general population and 10 percent of adults with asthma are aspirin-sensitive, possibly prompting asthma attacks and other reactions. For these people, an allergist may recommend steps to reduce sensitivity if the benefits of taking aspirin outweigh the risks.

The word is out

Savvy marketing, along with over-the-counter availability, have contributed to a surge in the number of people taking a therapeutic dose.

“I don’t think people view it as medicine,” says Dr. Whitsitt, “but that’s where you can get into trouble – when people take too much of it.”

More than one-third of  adults age 35 and older report taking aspirin at least every other day, with 75 percent citing heart benefit as the reason, according to findings released in January by the Centers for Disease Control and Prevention.

For aspirin to be protective against blood clotting, it needs to be taken at least every other day, or the body renews its production of platelets, Dr. Whitsitt says.

“I think patients through various media have an increased knowledge of aspirin as a preventive measure,” says Dr. Steven Thorson, a family practice physician at Family Clinic of Fort Collins. “Patients often do ask about aspirin if they’re in the risk category for heart disease. And if they don’t and they’re a good candidate for it, I’ll bring up the topic and also give them a handout about it to read.”

A new report found aspirin therapy helps prevent heart attacks in men and strokes in women but concluded bleeding risk to be similar between the sexes, according to a review published in the January issue of the Journal of the American Medical Association.

Talk with your doctor

Dr. Thorson encourages patients to make a list of questions to ask their doctor about preventive measures including aspirin therapy. “It’s an opportunity to look at the overall picture for the patient,” he says. “As family practice physicians, we not only treat illnesses but we believe in preventive care.”

And aspirin is but one piece of preventive care. Says Dr. Cooper: “Aspirin is an important part of an overall cardiovascular program, but it doesn’t replace making changes to your diet or quitting smoking.”

With so much health information out there to sort through, the challenge for consumers is weeding out preventive measures with solid scientific backing from those without. “This one (aspirin therapy) stands out with good data behind it,” Dr. Thorson says.

So, who should take aspirin as a preventive measure against heart disease? The old adage may be the most sound: Check with your doctor.