People who have recovered from COVID-19 have a “substantial” risk of heart disease up to 12 months after infection, according to a new study.
In one of the largest analyses of heart health in long COVID patients, researchers found that even those who recovered from a mild case could develop heart problems. Additionally, people who were younger than 65 and those lacking risk factors, like diabetes or obesity, were at elevated risk.
The study, published recently in Nature Medicine, examined data from a cohort of more than 150,000 veterans treated in the Veterans Health Administration system who had survived at least 30 days after testing positive for COVID-19. They compared them to millions of veterans who had been treated for other conditions.1
Researchers suggested that COVID-19 patients were more likely to develop heart problems after the first month post-infection and up to a year after recovery. The cardiovascular issues ranged from irregular heart rhythms, heart inflammation, and blood clots in the leg and lungs, to stroke, acute coronary disease, heart attack, and heart failure.
“Even a year out, people with COVID-19 are still experiencing heart problems that are attributable to COVID-19,” Ziyad Al-Aly, MD, study co-author and chief of research and development at the Veterans Affairs St. Louis Health Care System and clinical epidemiologist at Washington University in St. Louis, told Verywell. “Clearly, some people are not out of the woods and they’re still experiencing serious problems.”
People recovered from COVID-19 were 63% more likely to experience a cardiovascular outcome, according to the data. This means 45 out of every 1,000 participants in the study had heart health problems attributed to COVID-19.
The study also showed that the risk of cardiovascular disease increases with the severity of the COVID-19 infection. People who were hospitalized and those who were admitted into the intensive care unit were at greater risk of heart disease.
What This Means For You
If you’ve recovered from a COVID-19 infection in the last year, it’s important to keep in touch with your healthcare provider and pay attention to any new symptoms. Anyone who is experiencing a sudden onset of symptoms such as chest pain, intense muscle weakness, or shortness of breath should call 911 immediately.
Soaring Risk of Heart Problems From COVID-19
Al-Aly and his colleagues compared data from over 150,000 patients who survived COVID-19 for at least 30 days to two control groups—5.6 million people who hadn’t contracted COVID-19 and another 5.9 million whose data was collected in 2017, before the pandemic.
The COVID-19 group had an increased risk of stroke by 52%. Out of every 1,000 participants, four more people experienced stroke post-infection than those who were COVID-free. The risk of heart failure was elevated 72%, while the risk of pulmonary embolism—blood clots in the leg or lungs—was threefold higher.
Prior studies have suggested poor cardiovascular outcomes in people who recovered from COVID-19 after being hospitalized. For instance, a study of 100 recovered COVID-19 patients in a German hospital found that 78% of patients had heart damage.2
The new findings build on this, indicating that even non-hospitalized individuals experienced long-term cardiovascular events. The severity of the COVID-19 infection remained important, however—in people with COVID-19 who received care in the ICU, there were more than 10 times as many cases with heart disease per 1,000 people as those who didn’t require hospitalization.
When the researchers compared post-COVID-19 patients to the control group, they found increased risk of cardiovascular outcomes regardless of factors like obesity, hypertension, and smoking history.
“It really didn’t matter if you were young or old, if you had diabetes or not, if you were a smoker or not, if you had high BMI or not—there was still a significant risk associated with COVID-19 and cardiovascular problems,” Al-Aly said. “It was really almost like an equal opportunity offender.”
Limitations of the Study
In using data from the Department of Veterans Affairs, the researchers were able to analyze an exceptionally large cohort and track changes in subjects’ health time.
Despite the scope of the study, Naveen Pereira, MD, consultant for the department of cardiovascular diseases and professor of medicine at the Mayo Clinic College of Medicine, urged caution when applying the findings of this study to the general U.S. population. About 90% of those studied are male, more than 70% are White, and the mean age was over 60 years old.
“We assume these results are true for all subgroups,” Pereira said. “But it’s a problem because the representation of these subgroups is small. I would say that maybe this is a signal, but it’s uncertain.”
Pereira added that the study group was relatively unhealthy. For instance, more than half the population had a BMI of more than 30 and more than half were current or former smokers.
“Whether [COVID-19] causes new heart problems in people who have never had cardiac risk factors or underlying cardiovascular disease, we can’t say for sure from the findings of this study,” Pereira said.
How Does COVID-19 Affect Heart Health?
Scientists don’t yet know the precise ways in which COVID-19 leads to heart problems—the study authors cite a handful of theories.
COVID-19 may affect the cardiovascular system much like other viruses—such as influenza3 and certain enteroviruses4—which have been known to increase the risk of heart disease months later.
“What’s not clear from this paper is, ‘Is this something unique about COVID? Or is this just the same story we’ve already known about other types of pneumonia?’” Donald Lloyd-Jones, MD, ScM, president of the American Heart Association and cardiologist and chair of the department of preventive medicine at Northwestern University.
COVID-19 is a respiratory virus and doesn’t typically attack cells in the heart like viral myocarditis does. However, the COVID-19 virus can circulate in the blood, damaging blood vessels and causing issues in all the body’s major organs. COVID-19, like pneumonia, can cause inflammation in the arteries, which hinders blood circulation and can lead to more clotting in the small blood vessels that feed key organs. Plaque that was already in the blood vessels could rupture, leading to a heart attack or stroke.
While each of the cardiovascular problems following COVID-19 infection are cause for alarm, some require more pressing treatment than others.
“There’s a gradation of severity,” Lloyd-Jones said, explaining that a stroke or pulmonary embolism could be particularly life-threatening or cause long-term health effects.
“It’s incredibly important for people to pay attention to new symptoms in the six to 12 months after an episode of COVID,” Lloyd-Jones said. “Look for new chest pains, unexpected or unexplained shortness of breath, sudden weakness in one arm or one leg—all those things should be a big red flag.”
Protecting the Heart
During the pandemic, adults in the U.S. are seeing an increase in overall blood pressure levels, weight gain, worsening control of diabetes. The uptick in risk factors for cardiovascular disease coupled with high COVID-19 case rates could lead to long-term heart health problems.
“Because of the chronic nature of these conditions, they will likely have long-lasting consequences for patients and health systems and also have broad implications on economic productivity and life expectancy,” the study authors write.
This study was conducted before the availability of COVID-19 vaccines. Now, three-quarters of U.S. adults are fully vaccinated.5
More research must be done to understand the effects on the heart in vaccinated people who experience breakthrough COVID-19 infections, and those who had an asymptomatic infection, Al-Aly said.
“There’s a lot there that we need to sort of unpack and understand to be able to really offer our patients a better diagnosis and better treatment,” Al-Aly said.
Health experts continue to emphasize that being vaccinated against COVID-19 is the best way to protect oneself from severe COVID-19 and the cardiovascular disease that could follow.
“Vaccines are extremely effective at reducing your risk of a severe infection—of hospitalization or death,” Lloyd-Jones said. “By doing that, they’re automatically reducing your risk for the sequelae [i.e. after effects] that come after—these heart attacks or strokes that could happen after an infection.”
Pereira said that while the findings won’t likely change how he treats patients, they do underscore the importance of careful screening for COVID-19 recoveries who report symptoms of cardiovascular illness.
“The results, to me, indicate that I have to have increased vigilance for patients who may have had COVID,” he said.
As scientists continue to investigate the causes and possible treatments for long COVID-19, Al-Aly said health systems and the government should work to support patients with long term heart problems.
“Because of the enormity of COVID-19 and the millions of lives that it affected, there could be millions of people in the U.S. with heart problems,” Al-Aly said.
“We dropped the ball on COVID,” he added. “Let’s not drop the ball on long COVID.”