Feb. 23, 2023 – In the largest and most diverse analysis to date, researchers have found that the risk of post-COVID heart attack or stroke was reduced by 41% in people who are fully vaccinated.
Even partial vaccination gave some protection, reducing the risk of a major heart event by about 24%.
“To our surprise, even partial vaccination was associated with lower risk of adverse cardiovascular events,” researcher Joy Jiang said in a statement. “Given the magnitude of SARS-CoV-2 infection worldwide, we hope our findings could help improve vaccination rates, especially in individuals with coexisting conditions.”
Being fully vaccinated was defined as having received at least two mRNA vaccine doses, such as from Moderna or Pfizer, or one dose of the Johnson & Johnson vaccine.
The study was published this week in the Journal of the American College of Cardiology. Researchers examined data for more than 1.9 million people ages 18 to 90 years old who were infected with COVID between March 1, 2020, and Feb. 1, 2022. They were followed for 180 days after diagnosis. The average age was 45 years old, and 56% of patients were women.
In addition to the size and diversity of the study lending importance to its findings, the analysis was one of the first to include people vaccinated with the Johnson & Johnson vaccine, in addition to those who got the mRNA vaccines from Moderna and Pfizer. Also, the study was the first to look at the protection offered by partial vaccination, the authors said.
They noted that previous studies have established that COVID infection increases the risk of major heart events and is also linked to long-term heart problems.
People with previous heart problems, type 2 diabetes, high cholesterol, obesity, or liver disease were all at an increased risk of having a major heart event, this latest study showed.
The authors said that limits of their study included not being able to distinguish repeat infections and not being able to isolate the strain of COVID-19 that caused infection.
Nationally, COVID-19 cases continue to decline, though about half of U.S. states are starting to report some increases, according to the New York Times data tracker and the American Medical Association.