(Photo by Irin Fierce on Shutterstock)
Cardiovascular disease is the number one cause of death in the United States, at a cost of about 700,000 lives per year. For decades, and as recently as 2022, doctors recommended that all healthy older people take a low dose (81 milligrams) of aspirin daily for primary prevention of heart disease and strokes.
When new research challenged the value of the benefits of prophylactic aspirin as a blanket recommendation for all older, healthier adults, the American College of Cardiology (ACC), the American Heart Association (AHA), and the United States Preventive Services Task Force (USPSTF) amended their recommendations. They advise against daily aspirin for people with no history of heart disease, due to potentially dangerous side effects.
Despite this change in recommendations, research indicates that about 29 million Americans with no previous heart disease are still taking aspirin for prevention. About 6.6 million do so without a physician’s recommendation.
So, what’s right for you when it comes to aspirin?
There is no simple answer, according to Yale cardiologist Michael Nanna, MD. In Yale Medical News he explains, “It depends on a variety of factors, including a person’s age, risk factors and individual medical history.”
Cardiovascular disease defined
Cardiovascular disease (CVD) is the term for diseases of the heart and blood vessels – a wide range of conditions and events:
- Coronary artery disease – Narrowing or blockage of the blood vessels that feed oxygen to the heart muscle
- Arrhythmias – Irregular heartbeats
- Hypertension – High blood pressure
- Peripheral artery disease – Narrowing or blockage of the blood vessels supplying oxygen to organs other than the heart and to the limbs
- Heart attack – Complete blockage of a coronary artery, preventing blood from reaching heart muscle
- Heart failure – The heart’s pumping is insufficient to meet the body’s needs for oxygen.
- Stroke – Blood supply to the brain is reduced or blocked, depriving the brain of oxygen. These can be caused by a blocked blood vessel or bursting of a blood vessel.
Risk factors for these conditions include:
Why physicians previously recommended aspirin therapy
Aspirin is one of a group of drugs called nonsteroidal anti-inflammatory drugs. You’re familiar with the group; it includes ibuprofen (Motrin) and naprosyn (Aleve). Among its numerous uses, aspirin is a blood thinner. It prevents platelets (small blood components) from forming clots.
Blood clots are the leading cause of heart attacks and strokes. For that reason, doctors have, for decades, recommended that adults in their 50s and older take a low-dose (81 milligrams) aspirin daily to prevent the disorders listed above. This is primary prevention—a disease has not yet occurred. The term secondary prevention applies when there is a history of disease in an individual and the goal is preventing future events.
Why change the guidelines?
The guidelines changed because the risks of taking low-dose aspirin outweighed the benefits. Because it’s a blood thinner, aspirin can increase the risk of bleeding in the gastrointestinal (GI) tract or bleeding into the brain, which is a type of stroke. Older adults are already at increased risk for GI bleeding, bleeding into the brain as a type of stroke, and head trauma causing bleeding into the brain. Aspirin heightens all these risks.
In 2018, three important studies showed the benefits and risks of preventing CVD with aspirin. These were the ASPREE, ASCEND, and ARRIVE studies. Two of the studies showed no benefit but increased risk of bleeding. One study showed a slight reduction in CVD risk, but also at the expense of increased bleeding risk. The bleeding risks outweighed the potential benefits.
These studies were done as primary prevention. None of the participants had already experienced CVD. For patients who had already experienced a cardiac event or undergone bypass surgery, there is “strong evidence” that aspirin helps prevent another event, according to the Journal of the America Medical Association (JAMA). It was determined that for aspirin as secondary prevention the benefits outweigh the risks.
Current guidelines for primary prevention
In response to the 2018 studies, both the AHA and the ACC changed their recommendations. They advise considering preventive aspirin for individuals at substantial risk for CVD, ages 40-70, but aspirin should be discontinued at age 70.
The USPSTF updated its guidelines to recommend against starting aspirin for primary prevention of CVD in patients 60 and older. They advise that patients ages 40 to 59 with a 10% or greater 10-year risk for occurrence of CVD should be considered on an individual basis.
Is low-dose aspirin right for you?
Most healthy older adults should not take preventive aspirin. For those who have been taking daily low-dose aspirin it should probably be discontinued. It’s a decision to make with your healthcare provider, considering your medical condition, age, family history, and other risk factors.
“This is about personalized medicine and shared decision-making,” Dr. Nanna says. “I take it on a case-by-case basis, where I’m weighing what I can estimate as a patient’s risk for heart attack and stroke and deciding whether that risk threshold is high enough that it would outweigh the bleeding risk associated with starting low-dose aspirin. And then I present the patient with that information, and we make a decision together.”
