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There are not many medications that are 125 years old while retaining their position as one of the world’s most used and affordable drugs. This one is highly effective and has only a small risk for bleeding complications.
Happy Birthday, aspirin!
Aspirin was first synthesised in Wuppertal, Germany, by Felix Hoffmann. The chemist was searching for a medication for his father, who suffered from severe joint pain. This prompted him to work on a new drug, acetylsalicylic acid or aspirin.
Like many of our earlier drugs, aspirin has its origin in nature. The bark of the willow tree became known as the “fever tree” following reports of its miraculous properties. An Argentinian monk, Calantha, who lived in Peru described how the bark, made into a powder and given as a beverage, cured people of high fevers. The Jesuits imported the Peruvian bark into Europe in the 17th century.
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Two centuries later, the active ingredient of the bark was isolated as quinine, which has a characteristically bitter taste. Salicylic acid was a further refinement, but produced irritant side effects, especially in the stomach and gullet. This problem was solved by the efforts of Hoffman, who worked for the pharmaceutical firm Bayer, with the production of a powder containing acetyl salicylic acid. Aspirin as we know it was born.
Today Aspirin is probably best known as a key cardiovascular drug, because of its action as an anti-platelet medication. The first study which showed that aspirin is effective in preventing further heart attacks in people who already experienced a myocardial infarction was published in 1974 in The New England Journal of Medicine. Now the evidence for using aspirin in secondary prevention of heart disease is strong. Long-term treatment with aspirin, which helps reduce clotting by making platelets in the blood less sticky, reduces the risk of a future heart attack or stroke by about a quarter.
In the past five years, a number of major trials clearly showed that aspirin is not effective compared with placebo in the primary prevention of stroke, heart attack or death from vascular disease
Aspirin also has a proven role in the secondary prevention of “mini-stroke” or transient ischaemic attack (TIA) and stroke. Given early after a TIA, it reduces the risk for a recurrent vascular event by 50 per cent; long-term treatment with the drug reduces the risk by 20 per cent.
It seemed a no-brainer to use aspirin also for the primary prevention of vascular events. However, in the past five years, a number of major trials clearly showed that aspirin is not effective compared with placebo in the primary prevention of stroke, heart attack or death from vascular disease. But the incidence of major bleeding was higher in people taking aspirin, with about one in 250 patients having a significant bleed. With such an unfavourable risk/benefit ratio, the hope that aspirin use could be promoted for everyone faded.
Cancer defence
Aspirin’s place as a wonder drug is copper-fastened by its ability to reduce the incidence of a broad range of cancers. Taking low-dose aspirin on a daily basis reduces overall cancer mortality by one-fifth.
Regularly taking aspirin reduces the 20-year risk of death by about 10 per cent for prostate cancer, 30 per cent for lung cancer, 40 per cent for colorectal cancer and 60 per cent for oesophageal (gullet) cancer. The lung cancer and oesophageal cancer benefits kick in after taking a daily aspirin for five years; for a reduction in prostate cancer, a daily aspirin dose for 15 years is needed.
Just last week, aspirin was part of another milestone in medication history. The results of a major trial of the polypill were launched at the annual congress of the European Society of Cardiology (ESC). For people who had experienced a heart attack six months previously, taking a polypill containing aspirin, a statin (to lower lipids) and an ACE inhibitor (to control blood pressure) significantly reduced the risk of a further heart attack or stroke.
Aspirin: from willow bark to the polypill, it’s been some journey.