Latest COVID vaccine may have unexpected health benefit, study suggests

Key Points:

• A new study of over one million U.S. 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 heart attack, cardiovascular death, and hospitalization for heart failure.
• The vaccine showed the greatest benefit in adults aged 75 and older and those with underlying health conditions, with a 50.7% effectiveness at preventing COVID-associated cardiovascular events in the oldest group.
• Researchers compared veterans who received both the COVID and flu vaccines on the same day 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%) among those who got the COVID vaccine.
• Experts note the findings align with previous research showing vaccines reduce infection-related inflammation that can trigger cardiovascular complications, though this observational study cannot prove causation.
• The overall benefit observed was smaller than in earlier studies, possibly due to milder recent COVID variants, prior immunity, and reduced testing, but vaccination remains recommended to lower cardiovascular risks linked to COVID-19.