This transcript has been edited for clarity.
Dear colleagues, I am Christoph Diener from the faculty of medicine at the University of Duisburg-Essen in Germany.
Usually in this video series, I report on interesting scientific studies in the field of neurology published in the last month. But I have to admit, June was a lousy month for new science in neurology. Therefore, this month I’d like to take a different approach and tell you about a very interesting, old drug.
We are celebrating the 125th anniversary of aspirin. Aspirin was first synthesized in Wuppertal, Germany, a city which is only 40 km from my location, by Felix Hoffmann. Hoffmann was searching for a new drug for his father who suffered from severe joint pain, and the available drugs at that time had terrible adverse events. This prompted him to work on a new drug, which was later called aspirin acetylsalicylic acid.
Aspirin has been used very successfully to the present day as therapy for joint pain or arthritis. But as you know, it’s also effective in headaches, in particular, tension-type headache. I think it’s one of the most used drugs in the world for the treatment of acute migraine attacks.
It’s also available in some European countries in intravenous form for the treatment of severe migraine attacks or in the emergency room, and it’s as effective as subcutaneous sumatriptan. It’s also an effective migraine preventive drug in a dose of 300 mg/d.
Discovering aspirin’s antiplatelet activity
There was an interesting observation by a dentist in the 1930s, who noted bleeding when he extracted teeth in people who took aspirin for joint pain. When he started to ask his patients about possible bleeding complications and vascular events, he observed that people who took aspirin didn’t have coronary myocardial infarctions.
It took a long time for people to discover that aspirin is not only a pain medication but also an antiplatelet agent. The first randomized study that showed that aspirin is effective in secondary prevention after myocardial infarction was published in 1974 in The New England Journal of Medicine. In 1980, aspirin was approved by the U.S. Food and Drug Administration for the secondary prevention of stroke and in 1984 for secondary prevention after myocardial infarction.
A history of efficacy
Aspirin also has a proven role in the secondary prevention of transient ischemic attack and ischemic stroke. Given early, it reduces the risk for a recurrent vascular event by 50% and long-term, compared with placebo, by 20%.
Interestingly, the doses are different in different areas of the world. In the United States, it’s either 81 mg or 325 mg. In Europe, it’s usually 100 mg. Until a few years ago, there was no single trial which used 100 mg of aspirin, compared with placebo for the secondary prevention of stroke.
If we look at dual antiplatelet therapy, the combination of aspirin and clopidogrel was not superior to aspirin alone or clopidogrel alone for long-term prevention, but the combination of dipyridamole and aspirin and the combination of cilostazol and aspirin were superior to aspirin alone for secondary stroke prevention. Short-term, within the first 30 days, the combination of aspirin and clopidogrel and the combination of ticagrelor and aspirin is superior to monotherapy but also have an increased risk for bleeding.
People with atrial fibrillation or embolic strokes need to be anticoagulated, but the addition of aspirin to anticoagulation does not increase efficacy, it only increases the risk for bleeding.
In people above the age of 75 years who have to take aspirin, there is an increased risk for upper gastrointestinal bleeding. These patients should, in addition, receive proton pump inhibitors.
The use of aspirin for the primary prevention of vascular events was promoted for almost 50 years all over the world, but in the last 5 years, a number of randomized trials clearly showed that aspirin is not effective, compared with placebo, in the primary prevention of vascular event stroke, myocardial infarction, and vascular death. It only increases the risk for bleeding.
So it’s a clear separation. Aspirin should not be used for primary prevention of vascular events, but it should be used in basically everyone who doesn’t have contraindications for secondary prevention of vascular events and vascular death.
Ladies and gentlemen, a drug that is 125 years old is also still one of the most used and affordable drugs all around the world. It’s highly effective and has only a small risk for major bleeding complications. It’s really time to celebrate aspirin for this achievement.
Dr. Diener is professor, department of neurology, Stroke Center-Headache Center, University Duisburg-Essen (Germany). A complete list of his financial disclosures is available at the link below.
A version of this article first appeared on Medscape.com.