COVID-19 vaccines were associated with a lower risk of major adverse cardiovascular events in a cohort study of veterans.The 2024-2025 vaccines also demonstrated effectiveness against COVID-associated emergent care, hospitalization, and critical illness among adults.Among older adults who received a 2025-2026 vaccine, overall COVID vaccine effectiveness against symptomatic disease was 59%.
COVID-19 vaccines were associated with a lower risk of major adverse cardiovascular events (MACE), in addition to other outcomes, particularly among older adults, according to three studies.
Among over 1 million veterans who received the 2024-2025 COVID vaccine, vaccine effectiveness was 37.7% (95% CI 18.2-54.9) for preventing COVID-associated MACE, a composite endpoint of cardiovascular death, myocardial infarction, stroke, and heart failure hospitalization, with a risk difference per 10,000 people of 2.04 (95% CI 0.85-3.65) versus those who didn't get a COVID vaccine, reported Ziyad Al-Aly, MD, of the VA St. Louis Health Care System, and colleagues in JAMA Internal Medicine.
Looking at each endpoint, COVID vaccination was 57.9% effective at preventing COVID-associated cardiovascular death (95% CI 25.2-78.2), with a risk difference of 1.0 per 10,000 people (95% CI 0.3-2.1). Vaccination was 38.5% effective against COVID-associated myocardial infarction (95% CI 4.3-62.3), and 41.9% effective against COVID-associated hospitalization for heart failure (95% CI 4.1-67.5).
