January 12th, 2015

High Rate of Inappropriate Use of Aspirin for Primary Prevention

More than a third of U.S. adults — more than 50 million people — now take aspirin for the primary and secondary prevention of cardiovascular disease. Although it was once broadly recommended, aspirin for the primary prevention of cardiovascular disease is now only indicated in people who have a moderate-to-high 10-year risk. Now a new report published in the Journal of the American College of Cardiology finds that there are still a significant number of people who are receiving aspirin inappropriately.

Different medical groups have various recommendations about the precise indications for aspirin for primary prevention, but there is broad agreement that aspirin is not appropriate in people who are at low risk, defined as a 10-year risk below 6%. Using data from more than 68,000 primary-prevention patients receiving aspirin who were followed in the National Cardiovascular Disease Registry Practice Innovation and Clinical Excellence (PINNACLE) Registry, researchers calculated that 11.6% of the patients had a 10-year risk below 6%. Women were more likely than men to receive aspirin inappropriately. Inappropriate use varied significantly at the practice level, ranging from 7.2% in the lowest quartile to 13.6% in the upper quartile. People who received aspirin inappropriately were 16 years younger, on average, than people who received aspirin appropriately. Over time the rate of inappropriate use has declined, from 14.5% in 2008 to 9.1% in 2013.

“Our findings suggest that there are important opportunities to improve evidence-based use of aspirin for primary CVD prevention.” the authors concluded.

In an accompanying editorial, Freek Verheugt expresses concern that “the benefit of aspirin may be overshadowed by the bleeding hazard,” especially since the bleeding risk appears to be strongly correlated to the ischemic risk of the patient. He further speculates that because for many patients statins and other drugs will have already produced a substantial reduction in risk, any benefit from aspirin will have been almost completely eliminated.


5 Responses to “High Rate of Inappropriate Use of Aspirin for Primary Prevention”

  1. What about cancer prevention? While it is true that not everyone should take daily aspirin to prevent heart attacks, aspirin has also been shown to have other benefits. First, aspirin reduces the risk of cancers of the colon, esophagus, stomach, rectum, and prostate. Second, there is increasing evidence that it may help protect against Alzheimer’s disease. I realize that we on CardioExchange are focused on cardiovascular issues, but we should not ignore the benefits of aspirin in cancer and Alzheimer’s.

  2. H Robert Silverstein, MD says:

    My goodness: 1 meta analysis and common sense logic is out the window. I don’t think so. I am aware of previous widely accepted incorrect clinical judgments such as the Vineburg and radical mastectomy procedures. We must be wary of these top down pronouncements and until a truly double blind, placebo controlled crossover study of 10 years duration on this issue (which will never occur) is completed, I think I’ll continue using clinical judgment re when to use aspirin or not. H. Robert Silverstein, MD, FACC

  3. I have been asking the same question myself since this debate started. The overarching benefit must be looked at. Also, no one ever talks aspirin resistance and the value of the aspirin sensitivity test. Imagine a low risk patient on aspirin who is also resistant to the effects of aspirin. That is definitely ineffective prescribing.

  4. Again, statins are implicitly given a status greater than deserved. Although 25% of the adult population in America take statin medication, it tends to be a cross section of the population that is 75% low risk subjects. Very little true risk stratification goes into statin prescription writing. I think an important analysis would look at the inappropriate use of statin medication in low risk subjects.

    As statins reduce heart attacks by only 25% and coronary death by about 15% on average, we need to look at the risks of statin overuse as a unique problem, not as an argument against aspirin use.

    Once we have a double blind, placebo controlled trial of aspirin, we will find that the reduction in heart attacks, ischemic strokes, DVT, and cancer more than make up for the risk for bleeding. An episode of non-fatal GI bleeding is not equivalent to a heart attack or stroke.

  5. carol vassar, MD says:

    More helpful than the statistics on “misuse” of aspirin would be statistics on the variation in benefit of aspirin found in the various studies that are of high quality.