top of page
Search
Writer's pictureFibonacciMD
Jul 18

Daily Low-dose Aspirin Therapy: Pros & Cons

What You Need To Know About Low-dose Aspirin Therapy

Thinking about starting daily low-dose aspirin? Discover the pros and cons, understand the guidelines, and learn why talking to your doctor first is essential.


InBrief

low dose aspirin

Updated by Stu Caplen, MD


Some 30-million Americans who are at least 40 years old take a small daily dose of aspirin (81 mg) in an attempt to prevent cardiovascular disease, cancer, and even dementia. Of these individuals, over 6-million Americans self-medicate with aspirin each day, taking the drug without a doctor’s recommendation.


The Daily Low-Dose Asprin Therapy Argument

Pro: A low daily dose of aspirin thins the blood, by keeping platelets from clumping, which can help prevent heart disease and clots that may lead to a heart attack or stroke.
Con: This same low daily dose of aspirin may increase the risk of hemorrhagic stroke, gastrointestinal bleeding, and stomach-ulcer development.

The use of daily low-dose aspirin therapy is a complex issue. In 2018, the results of three major clinical trials prompted the American Heart Association (AHA) and the American College of Cardiology (ACC) to change clinical practice guidelines, recommending against routine use of aspirin in people over age 70 and individuals at increased risk of bleeding with no existing cardiovascular disease (CVD). In March 2019, the AHA and the ACC recommended against routine use of low-dose aspirin in people at greater risk of bleeding (e.g., those with peptic ulcer) and in persons 70 years of age or older without either existing heart disease or history of stroke.  In addition, they recommended that adults 40 to 75 years of age being evaluated for cardiovascular disease prevention undergo a 10-year atherosclerotic cardiovascular disease (ASCVD) risk estimation and have a clinician–patient risk discussion before starting on aspirin.  It was further recommended that aspirin be used infrequently in the routine primary prevention of ASCVD because of lack of net benefit.


In 2022, guidelines from the US Preventive Services Task Force (USPTF) recommended that the decision to initiate low-dose aspirin for the primary prevention of cardiovascular disease (CVD) in adults aged 40 to 59 years who have a 10% or greater 10-year CVD risk be an individual one. Evidence indicates that the net benefit of aspirin use in this group is small. Persons who are not at increased risk for bleeding and are willing to take low-dose aspirin daily are more likely to benefit. The USPTF recommends against initiating low-dose aspirin use for the primary prevention of CVD in adults 60 years or older.


Results of A Study of Cardiovascular Events in Diabetes 7.4-year trial, (ASCEND) reported that aspirin reduced serious vascular events 12% in diabetics who did not have evident cardiovascular disease at the beginning of the trial, but the risk of major bleeding events was 29% higher than the controls. They found no evidence, in the 7.4 years of the study, of any decrease in gastrointestinal cancer risk in the aspirin group.


In a study of aspirin use for colorectal cancer prevention, with almost 95,000 subjects, it was reported that there was a 20% less risk of colon cancer for those subjects over 70 years of age that started aspirin before age 70, particularly those that used it for 5 years or more. There was no reduction in cancer risk in subjects who initiated aspirin at age 70 or older.


The American Medical Association recommends that physicians ask patients if they are taking unprescribed daily aspirin and advise them about the benefits versus risks. Instead of taking a baby aspirin, persons not at risk should consume a heart-healthy diet, exercise regularly, control blood pressure and cholesterol (including use of a statin or other lipid-lowering medication, if indicated), quit smoking, and maintain a healthy weight.


Takeaway for Patients

Patients should not self-medicate with aspirin. Instead, they should consult with their physicians about starting low-dose aspirin therapy. Further, suddenly stopping low-dose aspirin therapy may have a rebound effect that could trigger a blood clot and increase the risk of a heart attack. Therefore, anyone deciding to stop self-prescribed aspirin therapy should speak with a physician before making changes that may result in serious consequences.


Aspirin use in patients with heart disease is universally agreed on.  However, for primary prevention in patients without cardiac disease, the major bleeding risks that have been discovered may exceed the benefit aspirin will provide, and as such it is being recommended much less for this purpose.  Aspirin may reduce the risk of colorectal cancer if started before age 70, but it is a risk versus benefit decision that should be discussed with a physician.  Lifestyle and dietary changes, with cancer screening exams or colonoscopies, can also decrease colorectal cancer risk.


Editor’s note: When a patient asks me about stopping low-dose aspirin that was started without medical consultation for primary prevention, I am reluctant to stop it, especially if the patient has at least two major cardiovascular risk factors (eg, family history for cardiovascular disease, high blood pressure, dyslipidemia, diabetes, smoking, obstructive sleep apnea, obesity). If I am in doubt, I obtain an ultrasound of the carotid arteries to determine the degree of atherosclerotic plaque and/or a coronary calcium score by computed tomography scan to help identify an additional layer of risk.


References

  1. Agence France-Presse. The pros and cons of a daily aspirin: good for heart disease but it raises risk of internal bleeding. South China Morning Post Web site SCMP.com. January 24, 2020. Accessed March 2, 2020.

  2. American Heart Association News. Avoid daily aspirin unless your doctor prescribes it, new guidelines advise. American Heart Association Web site. https://www.heart.org/en/news/2019/03/18/avoid-daily-aspirin-unless-your-doctor-prescribes-it-new-guidelines-advise. March 18, 2019. Accessed March 2, 2020.

  3. ASCEND Study Collaborative Group, Bowman L, Mafham M, et al. Effects of aspirin for primary prevention in persons with diabetes mellitus. N Engl J Med. 2018;379:1529-1539.Retrieved from: https://www.nejm.org/doi/full/10.1056/NEJMoa1804988

  4. Berg S. New heart-disease prevention guideline: what physicians must know. American Heart Association Web site. https://www.ama-assn.org/delivering-care/hypertension/new-heart-disease-prevention-guideline-what-physicians-must-know. March 28, 2019. Accessed March 2, 2020.

  5. Final Recommendation Statement: Aspirin Use to Prevent Cardiovascular Disease and Colorectal Cancer: Preventive Medication. U.S. Preventive Services Task Force Web site www.usreventitiveServiceTaskForce.org. September 2017. Accessed March 2, 2020.

  6. Grisham J. Does an aspirin a day reduce the risk of colorectal cancer? Memorial Sloan Kettering Cancer Center Web site, www.mskcc.org March 21, 2017. Accessed March 2, 2020.

  7. Hart RJ, Halperin JL, McBride R, et al. Aspirin for the primary prevention of stroke and other major vascular events: meta-analysis and hypotheses. Arch Neurol. 2000;57:326-332.

  8. Huang WY, Saver JL, Wu YL, Lin CJ, Lee M, Ovbiagele B. Frequency of intracranial hemorrhage with low-dose aspirin in individuals without symptomatic cardiovascular disease: a systematic review and meta-analysis. JAMA Neurol.2019 [Epub ahead of print].

  9. Mahmoud AN, Gad MM, Elgendy AY, Elgendy IY, Bavry AA. Efficacy and safety of aspirin for primary prevention of cardiovascular events: a meta-analysis and trial sequential analysis of randomized controlled trials. Eur Heart J.2019;40:607-617.

  10. Mayo Clinic Staff. Daily aspirin therapy: understand the benefits and risks. Mayo Clinic Web site. www.mayoclinic.org. January 9, 2019. Accessed March 2, 2020.

  11. McNeil JJ, Woods RL, Nelson MR, et al. Effect of aspirin on disability-free survival in the healthy elderly. N Engl J Med.2018;379:1499-1508.

  12. O'Brien CW, Juraschek SP, Wee CC. Prevalence of aspirin use for primary prevention of cardiovascular disease in the United States: results from the 2017 National Health Interview Survey. Ann Intern Med. 2019;171:596-598.

  13. Ranger GS, McKinley-Brown C, Rogerson E, Schimp-Manuel K. Aspirin use, compliance, and knowledge of anticancer effect in the community. Perm J.2020;24: 19.116.

  14. Zheng SL, Roddick AJ. Association of aspirin use for primary prevention with cardiovascular events and bleeding events: a systematic review and meta-analysis. JAMA.2019;321:277-287.

  15. Arnett DK et al. 2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation. September 10, 2019. Vol 140, Issue 11, Retrieved from: https://www.ahajournals.org/doi/10.1161/CIR.0000000000000678#d1e1164

  16. U. S. Preventative Services Task Force. Aspirin Use to Prevent Cardiovascular Disease: Preventive Medication. April 26, 2022. Retrieved from: https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/aspirin-to-prevent-cardiovascular-disease-preventive-medication

  17. Guo C, Ma W, Drew DA, et al. Aspirin Use and Risk of Colorectal Cancer Among Older Adults. JAMA Oncol. 2021;7(3):428–435. Retrieved from: https://jamanetwork.com/journals/jamaoncology/fullarticle/2775175 Initially posted Feb. 2020

Comments

bottom of page