Study: Low-Dose Aspirin May Keep Hospitalized COVID-19 Patients off Ventilators

woman in kitchen taking aspirin
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Key Takeaways

  • The SARS-CoV-2 (COVID-19) virus can cause blood platelets to clump, leading to potential blood clots that damage organs.
  • Aspirin is known to thin the blood, helping to prevent blood clots in people who have cardiovascular disease.
  • A new study shows that people hospitalized with COVID-19 benefitted from taking low-dose aspirin.

For people hospitalized because of COVID-19, low-dose aspirin may decrease the chance of being admitted to the intensive care unit (ICU), being placed on a mechanical ventilator, or dying. 

A study recently published in the journal Anesthesia & Analgesia looked back at the medical records of 412 people admitted to the hospital with COVID-19. Of those 412 people, 314 did not take low-dose aspirin on a daily basis; 98 people had received low-dose aspirin within 24 hours of admission to the hospital or had taken low-dose aspirin within seven days prior to their admission. More than 50% of people who did not take low-dose aspirin were admitted to the ICU, compared with only 38.8% of the people who did take low-dose aspirin.

Of those admitted to the ICU, 48.4% of the people who did not take aspirin were put on mechanical ventilation to help them breathe, while only 35.7% of those who took aspirin needed to be put on a ventilator.

How Ventilators Work

When lungs aren’t getting enough oxygen, a mechanical ventilator helps to move air in and out, like a bellows used to blow air into a fire. Either a mask or an endotracheal tube are used to send the air into the lungs. The speed and strength of the air being pushed into the lungs is controlled by the doctor. Although life-saving when needed, the use of mechanical ventilation can lead to complications, such as pneumonia or damage to nerves or vocal cords.

“There was a significant increase in the use of endotracheal tubes in patients who were not on aspirin,” Jonathan Chow, MD, director, critical care medicine fellowship, assistant professor in the department of anesthesiology at University of Maryland School of Medicine, and lead author of the study tells Verywell. Whereas six patients who took aspirin had an endotracheal tube placed down their throat, 57 patients who did not take aspirin needed an endotracheal tube.

“The people we defined as having had taken aspirin [in our study] did so at home prior to hospitalization. They could have been taking aspirin for the primary prevention of cardiovascular disease or perhaps to treat symptoms of SARS-CoV-2 virus (COVID-19), such as headache,” Chow says. “And some patients were given aspirin upon arrival to the emergency room [prior to being admitted to the hospital], because if they had symptoms such as chest pain or shortness of breath, the protocol is to give an aspirin in case the patient is having a heart attack.”

Low-dose (81 mg) aspirin has been used as a therapy to decrease the risk of heart attacks and strokes caused by blood clots in people who have cardiovascular disease (CVD), but this dosage—commonly known as “baby” aspirin—is not harmless for everyone. Guidelines from the American Heart Association and the American College of Cardiology updated in March of 2019 stopped recommending that people older than 70 take low-dose aspirin to prevent CVD due to the increased risk of bleeding. However, a study from July 2019 showed that 29 million people who didn’t have CVD, including 6.6 million who were not told to take low-dose aspirin by their provider, were in fact taking it.

“One of the great things about aspirin is that it is available everywhere in the world. It is generic and already produced by many companies; it’s inexpensive, and people don’t have to be hospitalized to receive it like they do to be treated with remdesivir (Veklury), for example. But we definitely need cautious optimism,” Chow says. “While it’s great news that we were able to report the study results that we did, we need to wait for results of a randomized controlled trial before making recommendations [for using low-dose aspirin in people who have COVID-19]."

Jonathan Chow, MD

We definitely need cautious optimism. While it’s great news that we were able to report the study results that we did, we need to wait for results of a randomized controlled trial.

— Jonathan Chow, MD

How Aspirin May Help COVID-19 Patients

Aspirin has been used to help prevent blood clots because it inhibits cells in the bloodstream called platelets, which clump together to form clots in response to damage in a blood vessel.

“Not only is aspirin an anti-inflammatory agent, but as soon as it interacts with a platelet, it inactivates the platelet for the rest of its life. That’s how it’s a blood thinner,” Chow says. “And that is why we think that aspirin works so well in COVID-19 patients. We know they’re at risk of developing clots, leading to multi-organ failure.”

In fact, a study published in July showed a 31% increase in complications due to blood clots in people with COVID-19 who were in the ICU. Although the study led by Chow involved older adults (median age of 56.5 years) who are more likely to have been taking low-dose aspirin therapy to prevent a heart attack or stroke, COVID-19 has caused blood clots and organ failure in younger adults as well.

What This Means For You

Whether low-dose aspirin is helpful or harmful depends on who you are. If you are at risk of cardiovascular disease, it could be beneficial; but if you are at risk of ulcers and bleeding in your gastrointestinal tract, it could be harmful. And although low-dose aspirin was touted as a way to prevent colon cancer, a study published in August showed that, in people older than 70 years, taking low-dose aspirin daily may increase the risk of cancer spreading.

“As with any medication, there are always risks and benefits, such as bleeding or ulcers, Chow says. “We don’t want patients at home to just go start taking aspirin. The correct way to do this is for people to go to their doctor, so their doctor can look at their personal risks and benefits to see if aspirin might be recommended,” he says.

Instead of planning to rely on aspirin to reduce complications when you get sick with COVID-19, it is better to try to not get the virus in the first place. “It is always best to take primary prevention steps instead of trying to prevent complications,” Chow says. “Keep washing your hands, continue social distancing, and wear a mask.”

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. National Heart, Lung and Blood Institute. Mechanical ventilation.

  3. Smith SC Jr, Benjamin EJ, Bonow RO, et al. AHA/ACCF secondary prevention and risk reduction therapy for patients with coronary and other atherosclerotic vascular disease: 2011 update: a guideline from the American Heart Association and American College of Cardiology Foundation. Circulation 2011; 124:2458. doi:10.1161/CIR.0b013e318235eb4d

  4. O'Brien CW, Juraschek SP, Wee CC. Prevalence of aspirin use for primary prevention of cardiovascular disease in the United States: Results From the 2017 National Health Interview Survey. Ann Intern Med. July 23, 2019. doi:10.7326/M19-0953

  5. Klok FA, Kruip MJHA, van der Meer NJM, et al. Incidence of thrombotic complications in critically ill ICU patients with COVID-19Thrombosis Research. 2020;191:145-147. doi:10.1016/j.thromres.2020.04.013

  6. McNeil JJ, Gibbs P, Orchard SG, et al. Effect of aspirin on cancer incidence and mortality in older adults. J Natl Cancer Inst. August 2020. doi:10.1093/jnci/djaa114

By Donna Siegfried
Donna Siegfried is an award-winning journalist with over 30 years' experience. She is a member of the American Medical Writer’s Association.