Study Confirms COVID-19 Vaccines Pose Very Minimal Risk of Blood Clots: University of Buffalo Research

And study led by researchers from the University of Buffalo has confirmed that, Contrary to the claims of anti-vaxxersvaccines against Covid-19 present only a very minimal risk of venous thromboembolism (VTE) or blood clots. Furthermore, the study found that becoming infected with Covid-19 is what actually creates a significant risk of blood clots.

The article was published online on February 1 in the journal Journal of Clinical and Translational Science.

“This population-based study found only a minimal risk of blood clots after vaccination with Covid-19″, he said in a statement Peter L. Elkin, MDfirst author of the article and distinguished professor at the UB and president of the Department of Biomedical Informatics from the UB.

“Given the great risk of VTE from Covid-19 infection, the risk-benefit ratio strongly favored vaccination”said Elkin, also a UBMD internal medicine physician.

The study was launched to investigate whether or not receiving a COVID-19 vaccine increased the risk of developing VTE, a claim that had been widely circulated on social media and in mainstream media.

“Some were concerned that vaccination against Covid-19 could cause undue harm and VTE was one of the mechanisms implicated by anti-vaxxersElkin said. “We wanted to know the truth.”

The study period ran from January 1, 2020 (just before the detection of Covid-19 in the US) to March 6, 2022, and was based on data from veterans age 45 and older of the National Oversight Department of Veterans Affairs. The data included 855,686 people who had received at least one dose of a SARS-CoV-2 vaccine and an unvaccinated control group of 321,676 people.

To clearly identify whether vaccines might affect VTE risk, the researchers took into account many predictors of VTE, such as age, race, gender, body mass index, and others.

The study found that people vaccinated had a VTE rate of 1.3755 per 1,000 people, which is 0.1% higher than the baseline VTE rate of 1.3741 per 1,000 in unvaccinated people.

“The excess risk was approximately 1.4 cases per million vaccinated patients,” Elkin said. “Given the fact that the VTE rate with Covid-19 is magnitude greater than the trivial risk of vaccination, our study reinforces the safety and importance of staying up-to-date with Covid-19 vaccines,” he added.

He said that it has been reported in other studies that the slight increase in the risk of VTE in some vaccinated patients can be attributed to a phenomenon called vaccine-induced immune thrombotic thrombocytopenia (VITT, for its acronym in English). VITT is an immune response that results in fewer platelets that are also malformed and stickier, which can lead to VTE.

Elkin noted that the study is an example of how translational science can be applied to the most important scientific questions facing society today, in this case the demonstrate the safety of vaccines against Covid-19.

“This studio shows the power of big data where we can use data from electronic medical records in a rigorous way to answer questions that could never be adequately answered by a randomized controlled trial due to the small effect size and the need to recruit millions of patients for the conclusions“, said.

“It is an example of how biomedical informatics is answering important clinical questions that can help people recognize the benefit of vaccination against Covid-19 and improve compliance with this approved clinical guideline,” Elkin said.

Other co-authors from the UB are Wilmon McCray, Melissa Resnick, Kendria Hall y Gillian Franklin. Other coauthors are from the Department of Veterans Affairs, Knowledge-Based Systems and the Western New York VA Health Care System; Harvard Medical School and the University of Vermont.

The research was funded in part by grants from the National Library of Medicine and the National Center for the Advancement of Translational Sciences (NCATS) from the National Institutes of Health.