Double dose influenza vaccination may not improve cardiopulmonary outcomes in acute coronary syndrome

Brazil: A new study conducted by Henrique Andrade R Fonseca and his team showed that receiving two doses of the influenza vaccine before discharge did not improve cardiopulmonary outcomes when compared to outpatient standard-dose immunization in patients with acute coronary syndrome (ACS). The findings of this study were published in European Heart Journal.

The Vaccination against Influenza to Prevent Cardiovascular Events after Acute Coronary Syndromes (VIP-ACS) trial compared two influenza vaccination strategies after an ACS: double-dose quadrivalent inactivated vaccine is given before hospital discharge vs. standard-dose quadrivalent inactivated vaccine given in the outpatient setting 30 days after randomization. It was a randomized, multicenter, open-label trial with blinded outcome adjudication. The main result, which was evaluated using the win ratio approach, was a hierarchical composite of all-cause mortality, myocardial infarction, stroke, unstable angina, hospitalization for heart failure, urgent coronary revascularization, and hospitalization for respiratory reasons.

The key findings of this study were:

1. At 25 Brazilian locations throughout the course of two influenza seasons, 1801 participants were registered.

2. With 12.7% victories in the in-hospital double-dose vaccination group and 12.3% victories in the standard-dose vaccine group, the main result did not vary across the groups.

3. The major secondary outcome, a hierarchical composite of cardiovascular mortality, myocardial infarction, and stroke, showed consistent results.

4. The results of the time-to-first event analysis for the primary outcome matched those of the main analysis. Adverse outcomes were uncommon and did not vary by group.

In conclusion, when compared to outpatient standard-dose immunization among patients hospitalized with ACS in the VIP-ACS study, a double-dose quadrivalent influenza vaccine did not enhance cardiopulmonary outcomes.

Source: 

Fonseca, H. A. R., Furtado, R. H. M., Zimerman, A., Lemos, P. A., Franken, M., Monfardini, F., Pedrosa, R. P., Patriota, R. de L. S., Passos, L. C. S., Dall'Orto, F. T. C., Hoffmann Filho, C. R., Esteves, C., Salim, E. F., da Silva, J. H., … Berwanger, O. (2022). Influenza vaccination strategy in acute coronary syndromes: the VIP-ACS trial. In European Heart Journal. Oxford University Press (OUP). https://doi.org/10.1093/eurheartj/ehac472