New studies question what we thought we knew about aspirin
For decades, aspirin (acetylsalicylic acid) has been viewed
as something of a wonder drug. A staple in most households, people have turned
to it for everything from headache relief to heart attack prevention. However,
recent studies have raised some serious questions about the benefits of regular
From willow trees to medicine cabinets
A precursor to aspirin, found in willow tree leaves, was an
ancient medicine used for centuries, but it wasn’t until the 19th
century that acetylsalicylic acid was first produced. In 1899, Bayer dubbed it aspirin
and it became popular around the world as a pain and fever reducer.
In the 1970s, pharmacologist John Vane uncovered the mechanism
of aspirin (research that later helped earn him a Nobel Prize), and a series of
studies established aspirin’s anti-clotting properties. By the ‘80s, daily aspirin
usage was being recommended to prevent heart attacks and as treatment for those
who have already been victims of heart attack or stroke.
In fact, as Science Daily notes, “Nearly one-quarter of Americans over the age of 40 have reported taking aspirin daily even if they don’t have a history of heart disease or stroke.”
New studies show aspirin’s cons might outweigh the
Though aspirin’s reputation as being beneficial for
cardiovascular health remains strong – especially in the mind of the general
public – there have been a number of recent studies that suggest its risks
could outweigh the rewards:
- The ARRIVE trial, which involved over 12,000 participants with an estimated 10-year cardiovascular disease risk of 20–30%, was the first large randomized controlled trial to examine the safety and efficacy of primary prophylactic aspirin in this population. The study found that taking aspirin daily didn’t reduce the rate of primary cardiovascular events with no known cardiovascular disease and moderate risk.
- The A Study of Cardiovascular Events in Diabetes (ASCEND) trial included over 15,000 patients and focused on diabetes patients. As Krista Rossi of MD Magazine reports on the trial, “While aspirin treatment decreased the number of serious vascular events experienced by diabetes mellitus patients, the benefit was closely balanced by the number of bleeds caused with aspirin treatment—even among patients with a five-year vascular risk of 10% or more.”
- According to a study published in Family Practice, aspirin should no longer be recommended for primary prevention of heart attack or stroke unless the patient has already suffered from one of these events.
Ultimately it comes down to needing to weigh the cardiovascular benefits against the bleeding risks
What does the literature say?
Those are just a few studies that point to the possibility that we should re-think our assumptions about aspirin. But what if we take a more comprehensive look at the literature? Using the biomedical literature database Embase, we did a few searches focusing on aspirin and found the following:
- The current state of aspirin: Over 3,000 articles discussed randomized controlled trials around aspirin
- Since 1990, the number of possible reports about adverse events in the literature has increased significantly (see chart above)
These newer scientific findings have not escaped the notice
of regulators. The FDA and EMA are now both offering
recommendations of limited or reduced use of aspirin in general. Furthermore,
many other countries have also updated their guidelines on aspirin usage to
reflect the latest knowledge.
More research is needed
A better understanding of the drawbacks of aspirin does not mean the “wonder drug” might not have some other benefits worth exploring further. Scientific American reports that developing research is showing how aspirin may be able to help stop the spread of cancer cells. A cohort study published in Jama Network Open also showed that aspirin use of three or more times per week was associated with reduction in certain types of cancer mortality in older adults.
More studies and further investigation is still needed to
explore the ways aspirin can help or hurt patients. It’s already clear that a
more personalized approach to the use of the drug is important The question now
is how evidence-based medical practices can help us with the best use of this