While a daily, low dose of aspirin is worth recommending to patients who’ve survived a heart attack, recent research discourages this behavior for individuals who’ve never had a heart attack.

In the wake of this breakthrough, however, another study indicates millions of people still take aspirin daily, believing it will prevent heart disease without their providers telling them to do so.

What Did the Study Find?

The extent to which Americans preventatively take aspirin was largely unknown — until research published in the Annals of Internal Medicine and led by Colin O’Brien, MD, put out a rough estimate.

“Millions of people out there take aspirin,” O’Brien said. “We’re hoping our study will encourage providers to open up a dialogue with patients to ensure it’s right for them.”

The researchers found that nearly 30 million US adults aged 40 years or older take aspirin to prevent CVD despite recent evidence that warns against it. This includes nearly half of older adults without self-reported CVD and a quarter of adults without CVD but with a history of peptic ulcer disease.

Additional highlights from the study include:

• The largest subgroup of preventative aspirin users are aged 60 to 69 (10 million), followed by those aged 50 to 59 (7 million).

• Approximately half of adults age 70 or older who don’t have heart disease take a daily aspirin for preventative purposes.

• Being older, male-identified, and having cardiovascular risk factors (hypertension, hyperlipidemia, diabetes, and smoking) have statistically significant associations with aspirin use.

What Does the Study Mean for Healthcare Providers?

The bottom line: A substantial portion of patients may be taking aspirin without their provider’s knowledge.

“Heart disease is so common in our country, and there’s something attractive about taking an over-the-counter medicine for it,” O’Brien said. “That may be why it has become a common practice.”

These findings indicate a strong need for healthcare practitioners to inquire about their patients’ ongoing aspirin intake and to provide informed advice on the benefits and harms.

What Does Previous Research on Aspirin for Heart Disease Say?

Earlier this year, similar studies challenged the commonly recommended practice of patients taking a daily aspirin dose. The widespread notion was that aspirin’s blood-thinning properties could lower the chances of experiencing a first heart attack.

But when one of the studies reported that aspirin users experience an increased risk of internal bleeding, offsetting its already-marginal benefits, the American Heart Association and the American College of Cardiology revised their guidelines concerning everyday aspirin use:

• Adults 70 or older should not routinely take daily, low-dose aspirin (75 to 100 milligrams) to prevent CVD.

• Low-dose aspirin (75 to 100 milligrams) should not be administered for the primary prevention of CVD among adults of any age with an increased risk of bleeding.

• Only select adults between 40 and 70 years old — at a higher risk of CVD but not at an increased bleeding risk — might be considered for low-dose aspirin (75 to 100 milligrams) intake.

These guidelines do not apply to patients who have already experienced a heart attack or stroke or have undergone procedures to prevent cardiovascular events.