Researchers at the University of Maryland School of Medicine showed COVID-19 patients who were taking a daily low-dose aspirin for cardiovascular disease had a significantly lower risk of complications and death compared to those who were not taking aspirin.

The researchers looked through the medical records of 412 COVID-19 patients, age 55 on average, who were hospitalized over the past few months due to complications of SARS-CoV-2 infection. About a quarter of the patients were taking a daily low-dose aspirin (usually 81 milligrams) before they were admitted or right after admission to manage their cardiovascular disease.

The researchers found aspirin use was associated with a 44 percent reduction in the risk of being put on a mechanical ventilator, a 43 percent decrease in the risk of ICU admission, and — most important of all — a 47 percent decrease in the risk of dying in the hospital compared to those who were not taking aspirin. The patients in the aspirin group did not experience a significant increase in adverse events such as major bleeding while hospitalized. The study definitely showed an association or correlation but remember correlation does not mean causation.

Nevertheless, this is promising because if this finding is confirmed (through clinical trials with larger sample size), it would make aspirin the first widely available, over-the-counter medication to reduce mortality in COVID-19 patients. Aspirin is a very potent antiplatelet agent. As soon as aspirin interacts with a platelet, that platelet becomes inactivated and can no longer create clots.

In July a study published in the Journal of the American College of Cardiology reviewed the effect of anticoagulant drugs on outcomes among hospitalized Covid-19 patients. Like the recent aspirin study, the investigators found that anticoagulants significantly reduced the risk of death among certain groups of people with Covid-19. Although these studies are encouraging, we need to wait for further studies to be done. Aspirin came into being in the late 1890s in the form of acetylsalicylic acid when chemist Felix Hoffmann at Bayer in Germany used it for his father’s rheumatism but salicin, which comes from the bark of the willow plant has been widely used hundreds of years before that.

Now, aspirin Is not only used to reduce pain, fever, or inflammation but is also the cornerstone of therapy to prevent a heart attack or a stroke since 1970s but the drug is not without risks. The greatest risk associated with aspirin is gastrointestinal bleeding so people who have a history of peptic ulcers or bleeding from the stomach should not take it.

The good news is the United Kingdom’s Recovery Trial, a large randomized controlled clinical study of potential COVID-19 treatments, will investigate aspirin as a possible therapy. Why aspirin? Patients with COVID-19 are at higher risk of blood clots forming in their blood vessels. Platelets, small cell fragments in the blood that stop bleeding, seem to be hyperreactive in COVID-19 and may be involved in the clotting complications.

Aspirin is already widely used to prevent blood clots in many other conditions but enrolling patients in a randomized clinical trial is the best way to assess whether there are clear benefits for patients with COVID-19 and whether those benefits outweigh any potential side-effects such as the risk of bleeding. At least 2,000 patients are expected to get 150mg of aspirin daily along with the usual regimen. Hopefully, in a few months, we’ll know whether aspirin is indeed good for patients with COVID-19.

The Recovery trial was the first to show that dexamethasone, a steroid that is also cheap and widely available, could save the lives of people severely ill with Covid-19. It also showed that the anti-malarial drug hydroxychloroquine provided no benefit in treating COVID-19 patients.