Why have recommendations changed, and what should you do?
Written by: Emily Lind
Medically reviewed by: Rob Philibert MD PhD
On October 12, 2021, the United States Preventive Services Task Force (USPSTF) released a draft recommendation statement on taking aspirin to preventively treat cardiovascular disease (CVD). The USPSTF now recommends that patients aged 40-59 years talk to doctors before taking low-dose aspirin to prevent CVD, and that anyone over 60 should not start taking the drug.
What is the USPSTF and why should I listen to them?
The USPSTF is an independent panel staffed by experts in preventive and evidence-based medicine. The Task Force reviews data on preventive treatments to help Americans understand their risks and benefits. To keep things simple, the USPSTF assigns a letter grade (A, B, C or D) to their recommendations based on the strength of the evidence and the pros/cons of preventive treatment. For patients aged 40-59, preventive low-dose aspirin scored a C, meaning that its use should be recommended on a case-by-case basis. For patients 60 or over, low-dose aspirin scored a D, meaning that the USPSTF discourages its use as a preventive CVD treatment. These recommendations are also backed by the American Academy of Family Physicians and are in agreement with the American Heart Association (AHA) as well.
Why has the recommendation changed?
USPSTF recommendations against preventive low-dose aspirin are based on a careful review of recent trials and simulation modeling which found that the net benefit was small for those not already at increased risk of CVD. This is because while aspirin can preemptively treat heart attacks and strokes by preventing clot formation, it can also negatively contribute to too much bleeding. For example, the USPSTF found that low-dose aspirin (≤100 mg/day) increased major gastrointestinal (GI) bleeding by 58%, and also increased intracranial hemorrhage (skull or brain bleeding).
Why does aspirin cause GI and brain bleeding?
The reason aspirin has broad-spectrum effects is that it works by irreversibly inhibiting cyclooxygenase enzymes COX-1 and COX-2. By acetylating COX-1 and COX-2, aspirin prevents the production of the inflammatory prostaglandin proteins and clot-promoting thromboxane proteins. The problem is that while COX-2 is generally only found in inflamed tissue, COX-1 is found throughout the body. This means that aspirin inhibits clotting and inflammation throughout the body, not just in organs impacted by CVD. So, while aspirin’s ability to prevent clots can be good for treating heart disease, it can also make GI and brain bleeds worse.
If it’s so dangerous, why was low-dose aspirin ever recommended?
You may wonder why daily low-dose aspirin was ever recommended considering the dangers. While aspirin has been a common drug since its discovery in 1897, it only began to be recommended as a preventive CVD treatment in the 1980s and 1990s. At this time, methods for controlling blood pressure and cholesterol were not as well developed. Despite its dangers, aspirin was one of the best available options at the time for patients at risk of CVD. There are now better preventive treatments available to patients.
What do I do now?
For years, many Americans have been taking aspirin as if it were a daily vitamin to prevent heart disease. But for most people aged 40-59, the dangers of low-dose aspirin may outweigh the benefits. Individuals need to discuss their risk of CVD with their doctor to determine the best course of action. However, with 25% of Americans going without a primary care physician, it can be hard to know how at-risk you are for heart disease.
One option for Americans seeking better prevention is through the use of the Epi+Gen CHD test from Cardio Diagnostics Inc. This test is accessible in the comfort of your own home through telemedicine appointments with doctors. Even better, it can better predict your 3-year risk of CVD than the standard lipid tests offered by most doctors. To learn more about Epi+Gen CHD and request the test, click here.
- Angela P. Cadavid (2017). Aspirin: The Mechanism of Action Revisited in the Context of Pregnancy Complications. https://doi.org/10.3389/fimmu.2017.00261
- Nina Zidar et al. (2009). Cyclooxygenase in normal human tissues – is COX-1 really a constitutive isoform, and COX-2 an inducible isoform? 10.1111/j.1582-4934.2008.00430.x
- Diarmuid Jefferys (2008). Aspirin: The Remarkable Story of a Wonder Drug. https://play.google.com/store/books/details/Aspirin_The_Remarkable_Story_of_a_Wonder_Drug?id=v9AZ76VD7ZYC&hl=en&gl=US
- Jake Miller (2019). “Fewer Americans are getting primary care,” The Harvard Gazette. https://news.harvard.edu/gazette/story/2019/12/fewer-americans-getting-primary-care-is-raising-concerns/