Role of Influenza Vaccination in Cardiovascular Disease: Systematic Review and Meta-Analysis

Influenza vaccination has shown great promise in terms of its cardioprotective effects. The aim of our analysis is to provide evidence regarding the protective effects of influenza vaccination in patients with cardiovascular disease. We conducted a systematic literature search to identify trials assessing the cardiovascular outcomes of influenza vaccination. Summary effects were calculated using a DerSimonian and Laird fixed effects and random effects model as odds ratio with 95% confidence intervals (CIs) for all the clinical endpoints. Fifteen studies with a total of 745,001 patients were included in our analysis. There was lower rates of all-cause mortality [odds ratio (OR) = 0.74, 95% CI 0.64-0.86], cardiovascular death (OR = 0.73, 95% CI 0.59-0.92), and stroke (OR = 0.71, 95% CI 0.57-0.89) in patients who received the influenza vaccine compared to placebo. There was no significant statistical difference in rates of myocardial infarction (OR = 0.91, 95% CI 0.69-1.21) or heart failure hospitalizations (OR = 1.06, 95% CI 0.85-1.31) in the 2 cohorts. In patients with cardiovascular disease, influenza vaccination is associated with lower all-cause mortality, cardiovascular death, and stroke.