Interview by Stephanie Desmon
Until now, people who suffered mild or asymptomatic COVID-19 were thought to have dodged the brunt of the virus’s brutal side effects. But new evidence has revealed that anyone infected with COVID is at higher risk for heart issues—including clots, inflammation, and arrhythmias—a risk that persists even in relatively healthy people long after the illness has passed.
In this Q&A, adapted from the March 9 episode of Public Health On Call, Ziyad Al-Aly, director of the Clinical Epidemiology Center and chief of Research and Education Service at Veterans Affairs St. Louis Health Care System, talks with Stephanie Desmon about COVID-19 and the heart, including his recent study, which found a significant risk of heart problems in people a year after being diagnosed with COVID.
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You just published a study that says that in some people who’ve had COVID, heart issues can persist for a year or more. What does this mean and what did you study?
We've known for a while that during the acute phase—the first 30 days of COVID-19—people who have severe disease and need to be admitted to the hospital or ICU may develop heart complications. We didn't know what happened to people's hearts in the long term—six months to a year out—or what happened to people who had mild disease and did not need hospitalization or ICU care.
We did this study to evaluate the one-year risk of heart problems in people who got COVID-19, compared to nearly 11 million controls of people who did not.
What did you find?
The major finding was that people with COVID-19 have a higher risk of all sorts of heart problems at one year. That included arrhythmias (irregular heart beats or the heart beating too fast or too slow) and atrial fibrillation (a fast heart rhythm in a particular pattern). We found evidence of an increased risk of stroke, of blood clots in the legs and the lungs, and of heart failure and heart attacks. The increased risk of a broad spectrum of heart problems was evident.
I went into it thinking that [the risk] was going to be most pronounced and evident in people who smoked a lot or had diabetes, heart disease, kidney disease, or some [other] risk factors. What we found is that even in people who did not have any heart problems start with, were athletic, did not have a high BMI, were not obese, did not smoke, did not have kidney disease or diabetes—even in people who were previously healthy and had no risk factors or problems with the heart—COVID-19 affected them in such a way that manifested the higher risk of heart problems than people who did not get COVID-19.
It was really eye-opening that the risk was also evident in people who did not have severe COVID-19 that necessitated hospitalization or ICU care. People who got COVID-19 and were asymptomatic, or got COVID-19 that was so mild that they were able to nurse it at home, without going to the doctor still developed an increased risk of heart problems a year out.
What's going on in the body?
A lot of different things could be happening. It's possible that the virus itself and the immune response to it cause an intense inflammation that subsequently hits the heart and results in some of the manifestations we've seen here. It's possible that COVID-19 may attack the endothelial cells that line the vessels of the heart. Some of these cells might die and eventually facilitate the formation of blood clots and blockages of the arteries or vessels of the heart.
There are several other mechanisms that revolve around something called the ACE receptor. The virus has something called a spike protein, which is like a key that engages a lock—the ACE receptor. That allows the virus into cells, including heart cells.
Why would SARS-CoV-2, the virus that causes COVID 19, which we all thought about as a respiratory virus, attack the heart up to a year down the road? That’s likely one of the explanations.
This study was done before vaccination was widely available. Is there any indication that, for example, breakthrough infections would have a different result long term?
Yes. We are [studying] this, but I think the jury is still out. We're certainly very interested in addressing that publicly as soon as we can.
You studied Veterans Administration records, and that population is mostly men, white, and older. Do you feel that [the findings] apply to the entire population?
Yes and no. I think we have to be cognizant that this study comes from one system, the VA system, but that needs to be put into a larger context. This is a study of nearly more than 11 million people. People tell me most vets are males, but 10% are females—meaning our study has more than 1 million females. Similarly, 20% [of study participants] are Black—more than 2 million people.
In addition to this, we did subgroup analyses to see what would happen in only women, only men, only Black people or white people, people younger than a certain age or older than a certain age. Across the board we saw an increased risk of heart problems. This tells us that it doesn't matter if you are a female or male, Black or white, older or younger, diabetic, a smoker, have chronic kidney disease or other cardiovascular risk factors, or not. The risk was across the board, and it’s driven by COVID-19. It really spared no one.
The jury's still out on all of the things that long COVID might encompass. Would this fit into that category?
Absolutely. Long COVID is the umbrella term that describes all the post-acute manifestations that happen as a result of COVID-19. It could be things that started in the acute phase that lingered and persisted into the long term, or it could be new things attributable to SARS-CoV-2 that have happened three, four, or five months out. When you have that definition in mind, it's very clear that the heart manifestations we described in our report are part and parcel of the broader picture of long COVID.
Long COVID can give you fatigue and brain fog and result in new-onset diabetes, kidney problems, and heart problems. All of that collectively forms a multilayered, multifaceted long COVID. That's not to say one patient will have all of these things.
Are we going to have a lot of people who have some form of long COVID and are chronically ill? Will it be a strain on government resources? What do you see as the future?
I think that's why talking about it is very important. We think long COVID can affect anywhere between 4% and 7% of people. That seems really small, but it’s not if you multiply that number by the huge number of people infected with COVID in the U.S., more than 80 million people and counting. We think that will translate into millions of people with long COVID in need of care, and broadly speaking, our health systems need to be prepared. People running health systems or clinics need to start preparing for the tide of patients that are going to hit our doors with heart problems and other long COVID problems.
On a government level, I think we definitely need to be prepared for this. We cannot move on from the pandemic and disregard its long-term consequences. Arguably the long-term consequences are going to be even more profound and stick with us and scar a lot of people around us for generations.
A lot of the manifestations we're describing in this report are chronic conditions that will [affect] people for a lifetime. For example, heart failure isn't something that you wake up tomorrow and all of a sudden don't have. That's not how it works. We're no longer talking about things that might improve tomorrow—we're seeing chronic conditions that will require care for a long time. People, health systems, and governments need to be prepared for that.
Stephanie Desmon is the co-host of the Public Health On Call podcast. She is the director of public relations and marketing for the Johns Hopkins Center for Communication Programs, the largest center at the Johns Hopkins Bloomberg School of Public Health.