Cardiovascular Outcomes Following Herpes Zoster Vaccination: A Systematic Review and Meta-Analysis

Herpes zoster vaccination (HZV) is primarily used to prevent the incidence of herpes zoster and its neurological complications. However, recent studies suggest a possible association with major cardiovascular events. Hence, we aimed to evaluate HZV's association with key cardiovascular outcomes. An electronic database search of PubMed, Embase, and Cochrane was carried out from inception to July 14, 2025, to find studies comparing key cardiovascular outcomes such as stroke, myocardial infarction, major adverse cardiovascular events, coronary artery disease, cardiac arrest, heart failure, and all-cause mortality in vaccinated versus unvaccinated individuals. A random-effects model was used, and pooled odds ratios (ORs) with their 95% confidence intervals (CIs) were calculated. A P value of <0.05 was considered statistically significant. A total of 9 studies were included. HZV was associated with a significantly reduced risk of stroke (OR: 0.79, 95% CI: 0.70-0.89; P = 0.0002), myocardial infarction (OR: 0.76, 95% CI: 0.65-0.89; P = 0.0005), major adverse cardiovascular events (OR: 0.77, 95% CI: 0.64-0.92; P = 0.004), coronary artery disease (OR: 0.77, 95% CI: 0.72-0.83; P < 0.00001), cardiac arrest (OR: 0.65, 95% CI: 0.44-0.98; P = 0.04), and all-cause mortality (OR: 0.56, 95% CI: 0.53-0.58; P < 0.00001). No significant associations were observed for heart failure (OR: 0.81, 95% CI: 0.58-1.14; P = 0.24). HZV was consistently associated with a reduced risk of mortality and several cardiovascular events, underscoring its potential as an effective, low-cost tool for cardiovascular disease prevention. However, high-powered studies are needed to confirm these associations.