LOS ANGELES — In the medical world, having heart disease puts you in a high-risk category that demands aggressive preventive care. Now, researchers have discovered something unexpected: surviving a severe case of COVID-19 may be just as dangerous for your heart as having cardiovascular disease – even if you were perfectly healthy before infection.
The alarming study suggests the virus can significantly increase cardiovascular risks for years after infection especially for those with certain blood types.
“We found a long-term cardiovascular health risk associated with COVID, especially among people with more severe COVID-19 cases that required hospitalization,” said lead study author Dr. James Hilser, from the University of Southern California Keck School of Medicine, in a statement. “This increased risk of heart attack and stroke continued three years after COVID-19 infection. Remarkably, in some cases, the increased risk was almost as high as having a known cardiovascular risk factor such as Type 2 diabetes or peripheral artery disease.”
Published in the journal Arteriosclerosis, Thrombosis, and Vascular Biology, the study found that hospitalization for COVID-19 represents what medical experts call a “coronary artery disease risk equivalent.” This means it raises your risk of serious heart problems to the same degree as having pre-existing heart disease. Even more concerning, this elevated risk persists for at least three years after infection and appears particularly pronounced in people with non-O blood types (A, B, or AB).
Drawing from an extensive dataset of over 227,000 participants in the UK Biobank, researchers identified 10,005 COVID-19 cases between February and December 2020, including 1,943 cases severe enough to require hospitalization. They then tracked these individuals for nearly three years, monitoring for major adverse cardiac events (MACE) — heart attacks, strokes, or death from any cause.
The findings paint a sobering picture: people hospitalized with COVID-19 were more than three times more likely to experience MACE compared to those who never had COVID. This increased risk remained consistently elevated throughout the entire follow-up period, showing no signs of diminishing even years after infection.
“Worldwide, over a billion people have already experienced COVID-19 infection. The findings reported are not a small effect in a small subgroup,” said co-senior study author Dr. Stanley Hazen, chair of cardiovascular and metabolic sciences in Cleveland Clinic’s Lerner Research Institute and co-section head of preventive cardiology. “The results included nearly a quarter million people and point to a finding of global health care importance that may translate into an explanation for a rise in cardiovascular disease around the world.”
More striking still was the discovery that COVID-19 patients who had no previous heart problems showed a 21% higher risk of cardiac events than people who had pre-existing heart disease but never contracted COVID-19. This suggests that a severe bout of COVID-19 is just as dangerous for your heart, if not more so, than having a history of heart disease.
Blood type emerged as a crucial factor in determining risk levels. People with non-O blood types (approximately 60% of the global population) who were hospitalized for COVID-19 showed about 65% higher risk of heart attacks and strokes compared to the general population. Meanwhile, those with type O blood showed no significant increase in risk. This represents one of the first documented instances of a gene-pathogen interaction affecting cardiovascular outcomes.
Dr. Sandeep R. Das, co-chair of the American Heart Association’s COVID-19 CVD Registry committee, called it “really two studies in one.” He noted that the blood type findings suggest “something located close to the genetic home of ABO blood type is associated with different degrees of susceptibility to COVID. This is really fascinating, and I look forward to seeing scientists tease out what the specific pathway may be.”
The relationship between COVID-19 and blood type has intrigued researchers since early in the pandemic, when studies first suggested that certain blood types might influence susceptibility to infection. This new research adds another layer to our understanding, showing that blood type not only affects your likelihood of catching the virus but may also influence your long-term cardiovascular risks after infection.
The study’s analysis suggests a potential protective role for antiplatelet medications (like aspirin) in COVID-19 patients, though more research is needed to confirm this finding. While the data showed some indication that these medications might help reduce cardiovascular risks in COVID survivors, the limited number of patients taking these medications in the study means this finding should be interpreted cautiously.
“The results of our study highlight the long-term cardiovascular effects of COVID-19 infection. Given the increased risk of heart attack, stroke and death, the question is whether or not severe COVID-19 should be considered as another risk factor for CVD, much like Type 2 diabetes or peripheral artery disease, where treatment focused on CVD prevention may be valuable,” said co-senior study author Hooman Allayee, Ph.D., a professor of population and public health sciences at the University of Southern California Keck School of Medicine in Los Angeles.
These findings carry important implications for both healthcare providers and COVID-19 survivors. The research team suggests that patients who have been hospitalized with COVID-19 might benefit from more aggressive cardiovascular risk reduction efforts – similar to how doctors treat patients with established heart disease.
Paper Summary
Methodology
The study utilized data from the UK Biobank, a massive biomedical database containing detailed health information on over half a million participants aged 40 to 69 at enrollment between 2006 and 2010. Researchers identified COVID-19 cases through both PCR test results and hospital records, creating matched control groups for comparison. They tracked participants for up to 1,003 days, using sophisticated statistical models to account for various demographic and health factors that might influence results.
Results
The study found that hospitalized COVID-19 patients had nearly four times the risk of major cardiac events compared to controls. This elevated risk persisted for the entire study period, with no sign of decreasing. People with non-O blood types showed particularly high risk, while those with type O blood appeared relatively protected. A preliminary analysis did not show that Rh (positive or negative) blood type interacted with severe COVID-19. The use of antiplatelet medications appeared to reduce some of the increased risk.
Limitations
The research was conducted using UK Biobank data from the early pandemic period, before widespread vaccination availability. The study couldn’t account for different COVID-19 variants or vaccination status, as all cases were from 2020 before vaccines were available. Additionally, medication use data wasn’t specific to the pandemic period, and the number of subjects taking antiplatelet agents was relatively small, particularly among primary prevention subjects. Because the majority of participants in the UK Biobank are white, additional research is needed to confirm these results apply to people with diverse racial and ethnic backgrounds.
Discussion and Takeaways
This research represents the first demonstration that COVID-19 hospitalization constitutes a coronary artery disease risk equivalent, suggesting that COVID survivors might benefit from more aggressive cardiovascular preventive measures. The discovery of the blood type interaction provides new insights into how genetic factors might influence post-COVID cardiovascular risks. The findings suggest that people with prior COVID infection may benefit from preventive care for cardiovascular disease.