A study published in Nature Communications from University of Cambridge found that the risk of heart attacks and strokes was up to 10% lower 13 to 24 weeks after the first COVID-19 vaccine dose. After the second dose, the risk dropped to 27% with AstraZeneca and 20% with Pfizer/BioNTech.
The study also showed similar reductions in other blood clot issues. Researchers from Cambridge, Bristol, and Edinburgh used health records from 46 million adults in England to compare cardiovascular disease rates before and after vaccination.
Co-first author Dr. Samantha Ip from the University of Cambridge said their study on nearly 46 million adults in England showed that heart attacks and strokes were similar or lower after COVID-19 vaccination than before or without vaccination. This supports the safety of COVID-19 vaccines, which have protected against severe COVID-19 and saved many lives.
Previous research found rare cardiovascular issues with some vaccines, like myocarditis with mRNA vaccines (e.g., Pfizer) and blood clots with adenovirus vaccines (e.g., AstraZeneca). This study supports those findings but did not find new risks, reassuring that the benefits of vaccination outweigh the risks.
Cardiovascular disease is higher after COVID-19, which might explain why vaccinated people have fewer heart attacks and strokes compared to unvaccinated people. Professor William Whiteley noted that over 90% of people over 12 in the UK were vaccinated with at least one dose by January 2022.
This England-wide study confirms that COVID-19 vaccines, including first, second, and booster doses, are safe for the heart. It shows that the benefits of these vaccines, with fewer heart attacks and strokes, outweigh the very rare cardiovascular issues.
The research team used secure data from GP practices, hospital admissions, and death records provided by NHS England.
Ongoing research on COVID-19 vaccines is crucial for understanding their benefits and risks. Access to large-scale data and collaboration between institutions made this study possible.
Journal reference :
- Ip, S., North, TL., Torabi, F. et al. Cohort study of cardiovascular safety of different COVID-19 vaccination doses among 46 million adults in England. Nature Communications. DOI: 10.1038/s41467-024-49634-x.