big european study was announced on heart Evidence suggests that COVID-19 vaccines reduce the risk of heart failure and blood clots in veins or arteries for at least six months after SARS-CoV-2 infection.

Researchers at Oxford University We conducted a time-lagged cohort study using electronic health records of 10.2 million never vaccinated and 10.4 million unvaccinated people based on national statistics. COVID-19 (new coronavirus infection) Vaccination campaigns were carried out in the UK, Spain and Estonia from January to July 2021.

The study period was dominated by alpha and then delta variants. Participants included adults of all ages and those at high risk for poor prognosis from COVID-19.

Unraveling the risks of infectious diseases and vaccinations

This study used vaccination as a time-varying exposure and included all of the following: COVID-19 (new coronavirus infection) Vaccines available in Europe during the study period: AstraZeneca/Oxford, Pfizer/BioNTech, Johnson & Johnson (J&J), Moderna.

Eligible study outcomes include ischemic stroke (IS), hemorrhagic stroke, transient ischemic attack (TIA), ventricular arrhythmia/arrest, myocarditis/pericarditis, and myocardial infarction (MI or heart attack). , heart failure (HF), pulmonary embolism (PE), and deep vein thrombosis (DVT). Venous thromboembolism (VTE) was used as a combination of PE and DVT, and arterial thrombosis/thromboembolism (ATE) was a combination of IS, TIA, and MI.

COVID-19 vaccines have been proven to be effective against infection, hospitalization, and death, but there have also been reports of unusual blood clots occurring after vaccination with adenovirus-based COVID-19 vaccines (from AstraZeneca and J&J). Yes, the authors noted, adding that they found a link. Between the mRNA vaccines (Pfizer and Moderna) and a small risk of myocarditis.

“On the other hand, SARS-CoV-2 infection can cause cardiac and thromboembolic complications,” the researchers wrote. “Previous studies have shown that the risk of serious complications remains high for up to a year after infection, although it gradually decreases over time.”

Additionally, the risk of blood clots and myocarditis, which are inflammations of the heart muscle, is much higher after being infected with the new coronavirus than after vaccination.

72% reduced risk for VTE at 3 or 6 months

Efficacy of the new coronavirus vaccine HF, VTEand ATE is The rates were 22%, 53%, and 45% at 1 month after SARS-CoV-2 infection, and 53%, 72%, and 61% at 3 to 6 months, respectively. A comparison of the Pfizer and AstraZeneca COVID-19 vaccines suggests a greater reduction in VTE than the former during the first month after vaccination, but other differences I was not able to admit.

COVID-19 vaccination has reduced the risk of heart disease and thromboembolism following COVID-19 infection. These effects are more pronounced in the outcome of acute COVID-19 infection, with a known reduction in severity after breakthrough compared to unvaccinated SARS-CoV-2 infection. Match.

”“COVID-19 vaccination reduced the risk of cardiac and thromboembolic outcomes after COVID-19,” the study authors wrote, “These effects CoV-2 is more pronounced in acute outcomes, consistent with the known reduction in severity of breakthrough infections compared to SARS without vaccination.” Infection. ”

They are concerned about the additive effects of COVID-19 vaccination on the risk of cardiac events and blood clots after vaccination and/or COVID-19 infection, as well as the potential for protection to decline over time and with new variants. , and called for future research on the effects of booster immunization. dose.