Almost from the start of the COVID-19 pandemic, researchers and medical experts feared – and often warned loudly – ​​that the virus was not like other infections people might face, such as during flu season. SARS-CoV-2 was different. It was worse. And the potential long-term effects, as we reported two years ago, were even more worrying.

A new large-scale study highlights these longer-term concerns. The results are as unforgiving as many experts had assumed.

The study, involving nearly a quarter of a million adults, found that people who had any type of COVID-19 infection in 2020 were twice as likely to suffer a cardiac event major (a heart attack, stroke or even death) within three years. a diagnosis than those who were not infected.

People whose infections were severe enough to warrant hospitalization had a nearly four times higher risk of a major heart attack or death than the uninfected group.

“These findings are undeniable and extremely troubling,” says David Putrino, director of the Cohen Center for Recovery from Complex Chronic Illness at the Mount Sinai School of Medicine. “The importance of this work is that our current public health policy regarding COVID-19 is inadequate. People need to be informed about the risks to their long-term health by being repeatedly infected with SARS-CoV-2.

There is a frightening truth in these words. As experts and leading medical institutions continue to debunk myths about the virus and the vaccines developed to combat it, longer-term research tells the story of lives irrevocably altered by COVID-19 infections and makes a strong case for support for vaccination and other mitigation measures against the virus. .

The study was published Oct. 9 in the peer-reviewed journal of the American Heart Association. Arteriosclerosis, thrombosis and vascular biology. The report’s authors and researchers analyzed data from the UK Biobank system, including data from more than 8,000 adults who had a positive laboratory test for COVID-19 in 2020 and approximately 2,000 others whose cases required hospitalization. The results were compared to nearly 220,000 adults in the database who were not diagnosed with COVID-19 during that time.

In the nearly three years after the acute infection in 2020, the study authors found that the risk of heart attack, stroke and death was doubled compared to the uninfected group. Somewhat surprisingly, elevated risks did not decrease over the three years of the study, suggesting a problem stay effect.

“The two-fold increased risk observed in the first year after infection was also observed in the second or even third year,” explains study author Stanley Hazen, chair of the Department of Cardiovascular and Metabolic Sciences at the Cleveland Institute of Medicine. Clinic. “This was observed in all subjects, regardless of age, gender, or heart disease risk factors.” (The ages of those in the study ranged from 50 to 86, with an average age of 67.)

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What’s more, In a subset analysis of hospitalized cases without known heart disease, infection with the virus increased the risk of heart attack, stroke or death to the same levels as individuals with a history of heart disease, diabetes or peripheral arterial disease (PAD)…but not COVID-19.

“That’s why we talk about COVID as an equivalent risk of coronary heart disease,” says Hooman Allayee, the study’s principal investigator and a professor at the Keck School of Medicine of USC in Los Angeles. “Getting severe COVID is just as bad for heart attacks and strokes as having pre-existing heart disease.”

The people I interviewed were quick to point out a critical distinction and key limitation of the study: None of the people were vaccinated at the time of their infection, because COVID-19 vaccines were not available. not available in 2020.

“The study did not examine the effects of COVID-19 vaccination on a person’s cardiovascular risk,” says Hazen.. “I suspect it would be protective, because vaccines generally prevent COVID infections from becoming serious.”

Putrino agrees. “Our team has consistently advocated for the public to focus on infection prevention strategies such as masking, clean air, and vaccination to best avoid acute SARS-CoV-2 infection,” he said. “The public should educate themselves about the long-term risks associated with COVID infection. »

How COVID-19 increases the risk of cardiovascular problems is the subject of much study and conjecture. Research on long COVID has highlighted the deleterious effects of the disease on normal body functions over time, and some of the same factors may well be at work here.

“COVID-19 could lead to inflammation of endothelial cells (which line blood vessels),” says Ziyad Al-Aly, chief of research and development at VA St. Louis Health Care, whose previous work predicted many of the results from the British biobank. study.

“It can also activate the complement system and increase the propensity to form clots; it can also destabilize or inflame plaques in the coronary arteries,” says Al-Aly. “These mechanisms may explain the significant increase in (cardiovascular) risk and the sustainability of this increase in risk over many years.”

Notably, the new study found that genetics also played a role. For example, hospitalization for COVID-19 doubled the risk of heart attack or stroke among people with blood types A, B, or AB, but did not change the risk for those with blood types O.

Allayee also says he would “very much like” to replicate the study’s main findings in other populations, “given that the UK biobank is predominantly made up of white Europeans.” He says the research group is already trying to access other data sets to do this.

But the results are strong and pretty clear: COVID-19 infection raises the stakes when it comes to heart attacks, strokes, and even death. This effect persists three years after infection. And serious infections make these risks even worse.

We know from other studies that vaccination can reduce the severity of infection, the need for hospitalization, and the risk of death associated with COVID-19 infections. Yet about one in five people in the United States had not received a single COVID-19 vaccine shot last year, let alone a full dose or an updated vaccine.

The study also found in a preliminary analysis that patients hospitalized with COVID-19 who were already taking aspirin did not have significantly increased cardiovascular risk. This suggests that the risk can potentially be mitigated, but still requires further study, says Allayee.

“I would use this data (from the study) as a sign to be more aggressive about prevention: healthy eating, exercise, controlling your blood pressure and cholesterol, quitting smoking,” says Sandeep Das, co-chair of the American Heart Association’s COVID program. -19 Cardiovascular Disease Registry Committee and Director of UT Southwestern Medical Center in Dallas. “I think this study should perhaps inspire some people to come out of their complacency and think about the risks they face in the long term.”

This process should involve vaccination. This may well involve more aggressive mask wearing and careful attention to the air quality around our daily routines. But none of this can happen without realizing that, as much as some people want to believe otherwise, COVID-19 remains an active threat to public and personal health, including your own history with the virus.

“You may have forgotten you had COVID years ago, but it hasn’t forgotten you,” Al-Aly says. “Trivializing COVID as a simple cold or an inconsequential hamburger is wishful thinking that does not correspond to scientific evidence. »

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