Primary prevention guideline downgrades aspirin, highlights social determinants

NEW ORLEANS — Described by its authors as “a one-stop shop” for the primary prevention of cardiovascular disease, a new guideline released March 17 by the American Heart Association (AHA) and the American College of Cardiology (ACC) runs the gamut from smoking cessation strategies to specific recommendations for treating cholesterol based on a patient’s 10-year risk of atherosclerotic cardiovascular disease.

The document replicates sections of the 2017 hypertension guidelines and 2018 cholesterol guidelines, and also updates the most recent U.S. guidelines for assessing cardiovascular risk, using lifestyle modifications to lower that risk and treating obese patients.

“Most importantly, for busy clinicians or people that are out there, this is a one-stop shop,” Amit Khera, MD, director of preventive cardiology at UT Southwestern School of Medicine and a co-author of the new guideline, said during the ACC’s annual scientific sessions. “This is one central resource for clinicians putting it all together with prior work as well as new and evolving components … and hopefully that will help in the effectiveness of implementation.”

As Khera alluded to, the new recommendations went beyond pooling together and updating previous work.

Here are four key takeaways from the guideline, which was published online in Circulation and the Journal of the American College of Cardiology.

1.  Aspirin isn’t a good preventive medication in most cases

Although it’s been used in primary CVD prevention for decades, aspirin has been downgraded in the new guidelines, largely on the strength of three trials published in the last year— ARRIVE, ASCEND and ASPREE. Those trials suggest the risk of bleeding outweighs the chances that aspirin will prevent one of the events it is designed to, such as a heart attack or stroke.

“I think this will be perhaps one of the more controversial or new or impactful components … only because so many people take aspirin currently and there’s a lot of misconceptions,” Khera said. “There have been three trials in the last year … which really have shown us that the place for aspirin has diminished in terms of primary prevention and that bleeding may be outweighing the benefit in the modern era with all of our preventive therapies.”

With this evidence in mind, the writing committee gave two Class III recommendations for low-dose aspirin (75-100 mg daily) in primary prevention, meaning aspirin for those indications may result in harm to the patient. Those “harm” recommendations include patients without ASCVD in their 70s or older, and for adults of any age who are at an increased risk of bleeding.

The committee gave a Class IIb recommendation for adults age 40 to 70 who are at higher ASCVD risk but not increased bleeding risk, suggesting aspirin “may be reasonable” in this scenario.

2. Social determinants of health are “front and center”

“The social determinants of health and how we are making that front and center, I think is the most impactful (part of the guidelines),” said guideline co-chair Donna Arnett, PhD, MSPH, dean and professor of epidemiology at the University of Kentucky.

“Because so many patients, we don’t even ask them, ‘Can you make it to the pharmacy to pick up your prescription? Do you have access to healthy food?’ We’ve made recommendations in the absence of that knowledge and it’s very hard for patients to adopt healthy lifestyles often because of their social disadvantage.”

While offering a couple of examples, the guidelines don’t give specific recommendations on how to address these social determinants. Instead, they aim to make it something in clinicians’ “background of thinking,” Arnett said.

John Warner, MD, past president of the AHA, agreed that social determinants of health—which include healthcare literacy, income and housing insecurity, among other issues—deserve a larger focus in primary prevention of CVD.

“Based on scientific evidence, we now know that only 10 to 20 percent of our health is actually determined by the healthcare that we receive and that 70 to 80 percent is impacted by social determinants of health,” he said. “Underserved and lower-income populations have a higher risk of developing heart disease and life expectancy can vary by more than 20 years by people living only five miles apart.”

3. Two classes of diabetes medication also reduce cardiovascular risk

Echoing a recent ACC consensus document for diabetic patients with established ASCVD, the primary prevention guidelines also suggest it may be reasonable (Class IIb recommendation) for diabetic patients to take sodium-glucose cotransporter 2 (SGLT2) inhibitors or glucagon-like peptide 1 receptor agonists (GLP-1RAs) to reduce cardiovascular events.

Both classes of medications have shown the ability to reduce CV risk, in addition to improving glycemic control, when taken in conjunction with metformin. Khera pointed out those trials were mostly composed of secondary prevention patients, although the medications also demonstrated some promise in individuals without a previous cardiovascular event.

4. Lifestyle recommendations are most important

The easiest way to prevent cardiovascular disease, the authors said, is to follow heart-healthy habits throughout the lifespan.

Warner estimates lifestyle modifications could prevent 80 percent of CVD events, but even incremental gains could have a big impact on patients and the U.S. health system.

The guidelines give a Class I recommendation to engaging in 150 minutes per week of moderate-intensity physical activity or 75 minutes of vigorous, aerobic physical activity—or an equivalent combination of the two approaches. They also give the strongest recommendation for a diet consisting of fruit, vegetables, whole grains, legumes, nuts and fish, while suggesting individuals stay away from sweetened beverages, processed meats, refined carbohydrates and trans fats (which drew a Class III/harm recommendation).

Arnett said 5.3 million premature deaths each year in the U.S. have been attributed to a lack of physical activity. Physical inactivity has also been tied to 9.6 percent of all healthcare expenditures in the country—about $105 billion per year.