USPSTF updates recommendations on aspirin and CVD

More on low-dose aspirin benefits and harms. What exactly is the absolute benefit and harm from daily low-dose aspirin use for primary prevention of CVD? As one might expect, it varies by age. Researchers used a microsimulation model to examine updated clinical data from systematic reviews. Looking at life years gained, the largest benefit was in men with a 10-year CVD risk of 20% and aspirin initiated between the ages of 40 and 49.³ This resulted in 52.4 lifetime years gained per 1000 people.³ The results from a meta-analysis of 11 studies, published in the evidence report, found an absolute reduction in major CVD events of 0.4% (number needed to treat = 250) and an absolute increase in major bleeds of 0.5% (number needed to harm = 200).² There was no reduction found for CVD-related or all-cause deaths.

One reason for the increased caution on using aspirin as primary prevention for CVD is the role that statins now play in reducing CVD risk, a factor not accounted for in the studies assessed. It is unknown if the addition of aspirin to statins is beneficial. Remember that the USPSTF recommends the use of a low- to moderate-dose statin in those ages 40 to 75 years if they have one or more CVD risk factors and a 10-year CVD risk ≥ 10%.⁴

How aspirin use might change. The use of aspirin for CVD prevention is widespread. One analysis estimates that one-third of those ages 50 years and older are using aspirin for CVD prevention, including 45% of those older than 75.⁵ If the recommendations from the USPSTF are widely adopted, there could be a gradual decrease in aspirin use for primary prevention with little or no effect on overall population health. Other interventions such as smoking prevention, weight reduction, high blood pressure control, and targeted use of statins—if more widely used—would contribute to the downward trend in CVD deaths that has occurred over the past several decades, with fewer complications caused by regular aspirin use.

Take-home message

Follow these steps when caring for adults ages 40 years and older who do not have known CVD:

1. Assess their 10-year CVD risk using the ACC/AHA tool. If the risk is ≥ 10%:

• Discuss the use of a low- or ­moderate-dose statin if they are age 75 years or younger.
• Discuss the potential for benefit and harm of low-dose aspirin if they are between the ages of 40 and 59 years.
• Mention to those taking daily low-dose aspirin that it has low benefit if continued after age 75.

2. Perform these interventions:

• Screen for hypertension and high cholesterol.
• Screen for type 2 diabetes and pre-diabetes in patients up to age 70 years who are overweight or obese.
• Ask about smoking.
• Measure body mass index.
• Offer preventive interventions when any of these CVD risks are found.