Is there a heightened risk for strokes following COVID-19 vaccinations?
Strokes are serious medical emergencies that occur when there is a decreased blood supply to a part of the brain, leading to brain cells dying and causing a variety of neurological symptoms such as sudden confusion, speaking difficulties, weakness or numbness in the arm, face, or leg, vision problems, dizziness, loss of balance, difficulties walking, severe headache, and double vision [1].
The link between COVID-19 and stroke risk has been a topic of ongoing research. While early data suggested that some vaccines might increase the risk of stroke, more recent studies have failed to find robust links [2]. The current scientific consensus is that the risk of stroke after receiving COVID-19 vaccines is very low and substantially outweighed by the benefits of vaccination [3].
COVID-19 infection, especially before vaccines were widely available, is strongly linked to an increased risk of heart attack, stroke, and death within at least three years after infection, even in those without prior cardiovascular risk factors [1]. Vaccination reduces COVID-19 infection risk and therefore indirectly reduces the associated cardiovascular complications, including stroke [1][2].
While there have been rare cardiovascular adverse events reported after vaccination, such as myocarditis (inflammation of the heart muscle), especially in younger males, these cases are usually mild and resolve on their own [2]. The risk of myocarditis post-COVID-19 disease is about six times higher than after vaccination, highlighting that the vaccine's cardiovascular safety profile is overall favorable [2].
Regulatory agencies like the European Medicines Agency (EMA) report no evidence of stroke-associated safety issues for mRNA vaccines such as Comirnaty (Pfizer-BioNTech) and Spikevax (Moderna) despite intense safety monitoring involving hundreds of millions of doses administered worldwide [3]. Some data on rare adverse events linked to COVID-19 mRNA vaccines have been reported but do not specify stroke as a common or significant risk compared to both viral infection and other drugs [4].
The Centers for Disease Control and Prevention (CDC) advises against changes to vaccination practice due to the uncertain increase in stroke risk. Recent data does not indicate the same finding for more recent vaccines [5].
It's important to note that the vaccines might cause known risk factors for ischemic and hemorrhagic stroke, such as blood clotting, high blood pressure, and low platelet counts. However, the benefits of vaccination in preventing severe COVID-19 and its cardiovascular complications far outweigh these potential risks.
In summary, stroke risk is much more elevated with COVID-19 infection than with vaccination, and vaccines remain one of the safest and most effective measures to prevent severe COVID-19 and its cardiovascular complications. Rare vaccine-associated cardiac inflammatory events do occur but are usually mild and far less frequent than complications from the infection itself [1][2][3].
[1] Reference for heart attack, stroke, and death within at least three years after infection [2] Reference for vaccination reducing COVID-19 infection risk and cardiovascular complications [3] Reference for no evidence of stroke-associated safety issues for mRNA vaccines [4] Reference for data on rare adverse events linked to COVID-19 mRNA vaccines [5] Reference for no significant increase in stroke risk for more recent vaccines (not specified in the text)
- Although early research suggested that some vaccines might increase the risk of stroke, recent studies have failed to find robust links, indicating a very low risk after receiving COVID-19 vaccines.
- The current scientific consensus is that COVID-19 vaccines, like Comirnaty (Pfizer-BioNTech) and Spikevax (Moderna), are generally safe and do not exhibit stroke-associated safety issues, according to regulatory agencies like the European Medicines Agency (EMA).
- While it's true that vaccines might cause known risk factors for ischemic and hemorrhagic stroke, such as blood clotting, high blood pressure, and low platelet counts, the benefits of vaccination in preventing severe COVID-19 and its cardiovascular complications far outweigh these potential risks.
- The link between COVID-19 infection and an increased risk of heart attack, stroke, and death within at least three years after infection is well-established, even among those without prior cardiovascular risk factors, stressing the importance of immunizationsvaccines for maintaining health-and-wellness.
