Covid vaccinations significantly reduce the risk of heart failure and potentially dangerous blood clots linked to the infection for up to a year, according to a major study.
Researchers analyzed health records of more than 20 million people across the UK, Spain and Estonia and found consistent evidence that the jabs protected against serious cardiovascular complications of the disease.
Covid vaccines, including those from Oxford-AstraZeneca, Pfizer and Moderna, have been highly effective in preventing serious illness in the pandemic, but drug regulators have also recorded increases in some rare heart and clotting conditions, similar to those found with other vaccines such as flu shots.
The latest study sought to examine the overall impact of a Covid vaccination, as infection with the virus itself is known to significantly increases the risk of heart failure and several other serious cardiovascular problems.
“What we show in this very large study is that people who are vaccinated have a much reduced risk of these complications post-Covid,” said Daniel Prieto-Alhambra, a professor of pharmaco- and device epidemiology at the University of Oxford. . a senior author on the study.
Write in the journal Heartthe researchers describe how the adenovirus-based Covid vaccines produced by Oxford-AstraZeneca and Janssen, and the mRNA-based vaccines from Pfizer and Moderna, were most protective against Covid-related heart failure and blood clots in the first month after receiving the contracted virus. .
In that period, the risk of heart failure was 55% lower, and the risks of blood clots in the veins and arteries were down 78% and 47%, respectively, compared to the figures in unvaccinated people.
While the protective effects of the vaccines waned over the longer term, those who received Covid injections had a lower risk of Covid-related heart failure and blood clots than unvaccinated individuals for up to a year, the researchers found.
Three to six months after infection, the risk of heart failure in vaccinated people was 39% lower than in unvaccinated people, with the risk of blood clots in the veins and arteries 47% and 28% respectively. From six to 12 months after infection, the risks of the same complications were 48%, 50% and 38% lower for vaccinated people, respectively.
The protective effect comes from the vaccines that reduce the severity of the disease when people experience it breakthrough infectionswhen the virus takes hold despite a person being vaccinated.
“The overall message is that if you get vaccinated, your risk of having post-Covid cardiovascular and thromboembolic complications is reduced quite dramatically,” Prieto-Alhambra said. “Especially for people who are at high risk, or afraid of cardiovascular complications or blood clots, this is very reassuring.”
