An Aspirin a Day? Not for All

For decades, health care professionals have recommended aspirin to help prevent heart attacks and stroke — even among some people without known heart disease. But newer data shows it’s not right for everyone. 

In fact, new recommendations from the American College of Cardiology and American Heart Association say an aspirin a day should be used rarely to prevent a heart attack or stroke in people without heart or blood vessel disease. That’s because you can take other steps to lower your chance of heart disease that can be more effective and have fewer side effects.  

Instead, aspirin should be limited to people who are very likely to develop heart disease or have a stroke, and who are not prone to bleeding, experts say. In other words, people who have the highest risk of cardiovascular disease and a very low risk of bleeding might consider taking a low-dose aspirin a day. 

Conflicting advice about aspirin over the years has made it difficult for patients and health care professionals to know what’s best. But as new study results are published, medical directions are updated to reflect what researchers have learned. You can find the latest recommendations in the newly released 2019 Primary Prevention Guideline. 

light bulb “The old expression ‘an aspirin a day keeps the cardiologist away’ is no longer true if you don’t have heart disease. Don’t presume you need an aspirin to prevent heart disease. On the other hand, if you have had heart disease or a stroke, aspirin is likely a part of your treatment. You shouldn’t stop taking it unless your doctor advises you to do so.” — Martha Gulati, MD, FACC, Editor-in-Chief of CardioSmart

How Does Aspirin Help?

Aspirin helps to reduce blood clots. When you cut yourself, your platelets — a type of cell that helps blood clump together — quickly act to help plug the wound and aid in healing. This is how your body forms clots. 

But when a blood clot forms in a blood vessel — especially one that is diseased or narrowed with plaque and other fatty deposits — it can block blood flow to the heart and cause a heart attack. If a blood clot travels to the brain, it can lead to a stroke.

Aspirin lowers the chances of a heart attack or stroke by making the blood less likely to stick together and clot. It helps the blood flow more easily through your body. That’s why people who suspect they are having a heart attack are often advised to chew an aspirin so it works quickly. 

But by disrupting your body’s ability to form clots, aspirin can also result in your bruising and bleeding more easily.

What Are the Main Concerns?

The main drawback: Taking aspirin every day can cause stomach upset and, in some cases, gastrointestinal (GI) bleeding. Although rare, aspirin has also been linked to a type of bleeding in the brain (called a hemorrhagic stroke).

Other side effects from aspirin may include:

  • Nausea
  • Belly pain or indigestion 
  • Itching
  • Skin rash
  • Nosebleeds
  • Allergic reaction in very rare cases

What Makes Bleeding More Likely?

It’s very important to tell your health care professional if you’ve had stomach problems or ulcers. Other conditions that may make excess bleeding more likely include:

  • Previous gastrointestinal or other uncontrolled bleeding (like a history of a bleeding ulcer)
  • Being 70 or older
  • Not having enough platelets (thrombocytopenia)
  • Bleeding disorders that impair the blood's ability to form clots
  • Chronic kidney disease

Use of other medications that affect your blood and bleeding also are factors. These include:

  • Blood thinners also called anticoagulants — sometimes used for atrial fibrillation — such as warfarin, apixaban, dabigatran, rivaroxaban, heparin
  • Clopidogrel, prasugrel or ticagrelor
  • NSAIDS or ibuprofen
  • Certain anti-depressants
  • Corticosteroids

Even dietary supplements, such as fish oil and gingko, can affect your bleeding risk. 

Who Should Avoid Aspirin? 

If you don't have heart disease, and haven’t had a heart attack or stroke, taking an aspirin daily to stay healthy isn’t a clear choice.

Recent research suggests that the long-term chance of bleeding from taking daily aspirin may be too high. Also, the evidence of benefit — that is, the number of heart attacks or strokes that are prevented — is not enough to make a daily aspirin worth taking for most adults. Healthy people who did not take an aspirin a day compared with those who did had similar rates of death from cardiovascular disease, according to several recent studies. 

People without heart disease and who have a low risk, or chance, of developing heart or blood vessel disease generally should not be taking an aspirin every day. 

Also, the new recommendations stress that daily aspirin may be more harmful than helpful for people without heart disease who:   

  • Are older than 70 
  • Are more prone to bleeding

The results of several major studies prompted new guidance because they question whether there is benefit from taking a daily aspirin to prevent heart attack or stroke in healthy people. The reduction in heart attacks and strokes is nearly offset by the chance of moderate to major bleeding, experts explain.

light bulb“Clinicians should be very selective in prescribing aspirin to people without known heart disease. It’s much more important to optimize lifestyle habits and control blood pressure and cholesterol as opposed to recommending aspirin.” — Roger Blumenthal, MD, FACC, co-chair of the ACC/AHA Primary Prevention of Cardiovascular Disease Guideline and the Kenneth Jay Pollin Professor of Cardiology at Johns Hopkins Medicine
The bottom line: An aspirin a day should be used rarely to prevent a heart attack or stroke in people without heart or blood vessel disease.

Who Should Consider Aspirin?

In some situations, daily low-dose aspirin therapy (75-100 mg) might be considered. For example, if:

  • You’re between 40 and 70 years old and you: 1) have a very high risk for developing blockages in your arteries or having a heart attack or stroke and 2) have low risk of bleeding.
  • You’ve had a computed tomography (CT) scan of the heart that shows at least a moderate amount of buildup of calcium in the heart’s arteries, which is an early sign of disease.

“The decision about whether someone should take a daily aspirin should be guided by an individual’s risk of developing heart and vascular disease, how likely they are to have problems with bleeding, as well as their personal preference and risk tolerance,” Dr. Blumenthal said. “In general, most healthy people will probably not benefit from taking an aspirin to prevent heart attacks or strokes.”

After Heart Attack or Stroke

If you’ve had a heart attack, stroke, open heart surgery or stents placed to open clogged arteries, taking aspirin every day can save your life.

Health care professionals routinely prescribe aspirin to help manage heart disease and prevent a second, potentially deadly heart attack or stroke. For the most part, the benefits outweigh the small chance of bleeding in people with known heart disease or those who’ve had a stroke. 

What Else Can I Do?

The good news is that there is a lot you can do to boost your heart’s health and help prevent a heart attack or stroke.

Contrary to what many people think, heart attacks and strokes aren’t simply destined to happen. In fact, most deaths from heart disease — more than 80% — can be prevented by: 

  • Eating healthy
  • Moving more
  • Keeping a healthy weight 
  • Avoiding or quitting smoking 

Talking With Your Health Care Team 

It’s important to talk with the people who provide your health care about your personal risk of developing heart disease or having a stroke.

Aspirin therapy is often used after someone has had open heart surgery, stents placed, a heart attack, or stroke. But it might not be a good option for preventing problems among people who don’t have a history of heart or vascular problems. Your preferences also factor into this decision. Be sure to share them and your concerns, too. 

Here are some questions you might ask:

  • Do I really need to take an aspirin every day? 
  • Should I be more focused on stepping up my efforts to adopt healthy habits?
  • Why is aspirin no longer recommended for some people?
  • How else can I lower my chance of developing heart disease or having a stroke?
  • Making lots of changes at once feels overwhelming. Are there certain health behaviors I should tackle first?
  • When would you recommend aspirin?
  • Do the new recommendations change how aspirin should be used after a heart attack or procedure? 
  • Which is better: a baby aspirin or regular strength? 
  • What does “enteric-coated” mean?

Prevention Home
Published: March 2019
Medical Reviewers: Roger Blumenthal, MD, FACC
CardioSmart Editor-in-Chief: Martha Gulati, MD, FACC

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