To Take Aspirin or Not To Take Aspirin, That is The Question!

The following article was written by Dr. Alaa Diab as a CardioNerds Conference Scholar for The American Society for Preventive Cardiology 2022 Congress on Cardiovascular Disease Prevention.

To take aspirin or not to take aspirin, that is the question! The use of aspirin in primary CVD prevention was hotly debated at the American Society For Preventive Cardiology (ASPC) 2022 Congress between two leading experts.

Aspirin has been a renowned medication in the world of primary cardiovascular disease (CVD) prevention, but no drug is risk free. The latest guidelines of the American Heart Association and American College of Cardiology 2019 recommend considering low dose aspirin for primary prevention in adults 40 to 70 years of age at high risk for Atherosclerotic Cardiovascular Disease (ASCVD) and not high risk for bleeding, the European Society of Cardiology 2021 guidelines recommend low-dose aspirin  in patients with diabetes or very high CVD risk, and the US Preventative Services Task Force 2020 guidelines recommend low-dose aspirin for adults ages 40-59 years with 10% or greater 10-year CVD risk as an individualized decision and against in adults 60 years of age or above.1,2,3 But do the benefits justify the risk?

The ASCEND study randomized 15,480 patients with diabetes but without evident CVD to receive aspirin 100mg daily versus matching placebo. They were followed for a mean of 7.4 years looking for the primary efficacy outcome of first serious vascular event (i.e., myocardial infarction, stroke or transient ischemic attack) or death from any vascular cause (not due to an intracranial hemorrhage). Compared with the control group, those assigned to aspirin had fewer primary endpoint events (8.5% vs 9.6%; rate ratio, 0.88; 95% CI, 0.79-0.97; P=0.01) but more major bleeding events (4.1% vs 3.2%; rate ratio, 1.29; 95% CI, 1.09-1.52; P=0.003).4

Michael Blaha, MD, MPH, a Professor of Cardiology and Epidemiology and Director of Clinical Research at the Ciccarone Center for the Prevention of Cardiovascular Disease at the Johns Hopkins Hospital discussed his latest research on the use of Coronary Artery Calcium scores in the use of aspirin for primary CVD prevention: “Coronary artery Calcium (CAC) can simplify the identification of patients who may benefit from low dose aspirin for primary prevention, notably a CAC more than or equal to 100 aspirin therapy should be considered given that there are no bleeding contraindications.” Hold your CVD prevention horses! One of the latest clinical trials highlighted by Ann Marie Navar, MD, PhD, an Associate Professor in the Departments of Internal Medicine and Population and Data Sciences at UT Southwestern Medical Center, is the ASPREE study. They enrolled 19,114 participants who were either assigned to receive aspirin or a placebo pill over the course of 4 years starting in 2010. They found that the risk of death from any cause was 12.7 events per 1000 person-years in the aspirin group and 11.1 events per 1000 person-years in the placebo group (hazard ratio, 1.14; 95% CI, 1.01 to 1.29).5 “Aspirin is only beneficial in high ASCVD risk groups who are less than 70 years of age, which represents a minority of the patients that we see in our CVD clinics for primary CVD prevention” said Dr. Navar.

Simply put, aspirin’s benefit the in primary preventing of CVD events comes at a cost of bleeding and even excess all-cause mortality. Ongoing work will hopefully help elucidate specific higher-risk populations for whom the aspirin may provide overall net benefit for primary prevention. It’s role for secondary prevention remains undisputed.

  1. Arnett DK, Blumenthal RS, Albert MA, 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 [published correction appears in Circulation. 2019 Sep 10;140(11):e649-e650] [published correction appears in Circulation. 2020 Jan 28;141(4):e60] [published correction appears in Circulation. 2020 Apr 21;141(16):e774]. Circulation. 2019;140(11):e596-e646. doi:10.1161/CIR.0000000000000678
  2. Visseren FLJ, Mach F, Smulders YM, et al. 2021 ESC Guidelines on cardiovascular disease prevention in clinical practice. Eur Heart J. 2021;42(34):3227-3337. doi:10.1093/eurheartj/ehab484
  3. US Preventive Services Task Force, Davidson KW, Barry MJ, et al. Aspirin Use to Prevent Cardiovascular Disease: US Preventive Services Task Force Recommendation Statement. JAMA. 2022;327(16):1577-1584. doi:10.1001/jama.2022.4983
  4. 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(16):1529-1539. doi:10.1056/NEJMoa1804988

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(16):1499-1508. doi:10.1056/NEJMoa1800722