Virus World

Covid vaccinations substantially reduce the risk of heart failure and potentially dangerous blood clots linked to the infection for up to a year, according to a large study. Researchers analysed health records from 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, proved highly effective at preventing severe disease in the pandemic, but medicines regulators 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 investigate the overall impact of a Covid vaccination, given that infection with the virus itself is known to significantly raise the risk of heart failure and various other serious cardiovascular problems. “What we show in this very large study is that people who are vaccinated are at a very much reduced risk of these complications post-Covid,” said Daniel Prieto-Alhambra, a professor of pharmaco- and device epidemiology at the University of Oxford and a senior author on the study. Writing in the journal Heart, the 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 contracting the 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 with rates in unvaccinated people.

While the protective effects of the vaccines waned over the longer term, those who received Covid shots remained at 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 down 47% and 28% respectively. From six to 12 months post-infection, the risks of the same complications were 48%, 50% and 38% lower, respectively, for vaccinated people. The protective effect arises from the vaccines reducing the severity of the disease when people experience breakthrough infections, when the virus takes hold despite a person being vaccinated. “The message overall is that if you are vaccinated, your risk of having post-Covid cardiovascular and thromboembolic complications is reduced quite dramatically,” Prieto-Alhambra said. “Particularly for people who are at high risk, or are scared of having cardiovascular complications or blood clots, this is very reassuring.”

Cites study published in 2024 in BMJ Heart:

https://doi.org/10.1136/heartjnl-2023-323483 

The cardiovascular complications of acute coronavirus disease 2019 (COVID-19) are well described, but the post-acute cardiovascular manifestations of COVID-19 have not yet been comprehensively characterized. Here we used national healthcare databases from the US Department of Veterans Affairs to build a cohort of 153,760 individuals with COVID-19, as well as two sets of control cohorts with 5,637,647 (contemporary controls) and 5,859,411 (historical controls) individuals, to estimate risks and 1-year burdens of a set of pre-specified incident cardiovascular outcomes. We show that, beyond the first 30 d after infection, individuals with COVID-19 are at increased risk of incident cardiovascular disease spanning several categories, including cerebrovascular disorders, dysrhythmias, ischemic and non-ischemic heart disease, pericarditis, myocarditis, heart failure and thromboembolic disease.

These risks and burdens were evident even among individuals who were not hospitalized during the acute phase of the infection and increased in a graded fashion according to the care setting during the acute phase (non-hospitalized, hospitalized and admitted to intensive care). Our results provide evidence that the risk and 1-year burden of cardiovascular disease in survivors of acute COVID-19 are substantial. Care pathways of those surviving the acute episode of COVID-19 should include attention to cardiovascular health and disease. Individuals with COVID-19 are at increased long-term risk for a wide range of cardiovascular disorders, even for individuals who were not hospitalized during the acute phase of the infection.

Published Nature Medicine (Feb. 7, 2022):

https://doi.org/10.1038/s41591-022-01689-3 

The COVID-19 pandemic has limited the access of patients with cardiovascular diseases to healthcare services, causing excess deaths. However, a detailed analysis of temporal variations of excess cardiovascular mortality during the COVID-19 pandemic has been lacking. Here we estimate time-varied excess cardiovascular deaths (observed deaths versus expected deaths predicted by the negative binomial log-linear regression model) in the United States. From March 2020 to March 2022 there were 90,160 excess cardiovascular deaths, or 4.9% more cardiovascular deaths than expected. Two large peaks of national excess cardiovascular mortality were observed during the periods of March–June 2020 and June–November 2021, coinciding with two peaks of COVID-19 deaths, but the temporal patterns varied by state, age, sex and race and ethnicity. The excess cardiovascular death percentages were 5.7% and 4.0% in men and women, respectively, and 3.6%, 8.8%, 7.5% and 7.7% in non-Hispanic White, Black, Asian and Hispanic people, respectively. Our data highlight an urgent need for healthcare services optimization for patients with cardiovascular diseases in the COVID-19 era. Ran et al. report that excess cardiovascular mortality in the United States during the first two years of the COVID-19 pandemic coincided with the waves of COVID-19 deaths and was demographically diverse.

Published in Nature Cardiovascular  Reserch (Feb. 27, 2023):

https://doi.org/10.1038/s44161-023-00220-2