Latest COVID vaccine may have unexpected health benefit, study suggests

Key Points:

• A new study of over one million US veterans found that the 2024-2025 COVID-19 vaccine was associated with a 37.7% reduction in COVID-related major adverse cardiovascular events (MACE), including cardiovascular death, heart attack, and hospitalization for heart failure.
• The vaccine showed the greatest benefit in adults aged 75 and older, with a 50.7% effectiveness in preventing COVID-associated cardiovascular events among this group.
• Researchers compared veterans who received both the COVID and flu vaccines to those who received only the flu vaccine, finding significantly lower risks of cardiovascular death (57.9%), heart attack (38.5%), and heart failure hospitalization (41.9%) in the COVID-vaccinated group; stroke risk reduction was not statistically significant.
• Experts noted the findings align with previous research suggesting vaccines reduce cardiovascular risks by preventing infection-related inflammation, though the study’s observational nature means it cannot prove causation.
• The overall benefit observed was smaller than in earlier studies, possibly due to milder COVID variants, existing immunity in the population, and reduced testing, but vaccination remains recommended to lower cardiovascular and infectious disease risks.