Effect of High-Dose Trivalent vs Standard-Dose Quadrivalent Influenza Vaccine on Mortality or Cardiopulmonary Hospitalization in Patients With High-risk Cardiovascular Disease: A Randomized Clinical Trial
RCT of 5260 US/Canadian adults vaccinated over 3 influenza seasons, found no difference in all-cause mortality or cardiopulmonary hospitalisation during each season for those in high-dose trivalent group vs standard-dose quadrivalent group (HR, 1.06; 95% CI, 0.97-1.17; P = 0.21).
Source:
Journal of the American Medical Association
SPS commentary:
A related editorial discusses the findings of this noting that the study did not examine “absolute efficacy” of either vaccine due to lack of a placebo or unvaccinated group. Furthermore, the trial assessed nonspecific outcomes rather than laboratory-confirmed influenza.