Older adults receiving a high dose of tetravalent flu The vaccine has a 49 percent lower risk of death and a 64 percent lower risk of hospitalization with influenza or
Pneumonia Compared with those receiving a standard dose vaccine, the results of the DANFLU-1 study showed.
The open-label trial was conducted in Denmark during the 2021/2022 influenza season in the Northern Hemisphere. 12477 participants aged 65-79 years (mean age 71.7 years, 47.1 percent female) were randomized in a 1:1 ratio to receive either a high-dose (n = 6245) or standard dose (n = 6232) quadrivalent influenza vaccine. They were followed up using nationwide administrative health care registries from 14 days after vaccination until 31 May 2022. Baseline characteristics were comparable between study participants and individuals of the same age in the general Danish population.
About 20 percent of the participants had chronic cardiovascular disease. The most common comorbidities were high blood pressure (52 percent), cancer (11 percent) and diabetes (9 percent).
The incidence of hospitalization with influenza or pneumonia was significantly reduced among individuals who received a higher dose versus the standard influenza vaccine (0.2 percent versus 0.4 percent; reduced relative risk). [rVE]64.4 percent, 95 percent confidence interval [CI]24.4-84.6%). [ESC 2022, Hot Line Session 2]
All-cause mortality was also significantly reduced in high-dose versus standard-dose influenza vaccine recipients (0.3 percent versus 0.7 percent; rVE, 48.9 percent; 95 percent CI, 11.5-71.3 percent).
Participants who received a high dose versus the standard influenza vaccine also reduced the incidence of hospitalization for respiratory disease (rVE, 40.1%; 95% CI, -1.8 to 65.5%), hospitalization for cardio and respiratory disease (rVE, 12.1) percent, 95 percent percent CI, -15.5 to 33.3 percent), and hospitalization for any cause (rVE, 6.9 percent, 95 percent CI, -5.2 to 17.6 percent).
Serious adverse event (SAE) rates were not significantly different between the high-dose and standard-dose vaccine recipients (6.0 percent vs 6.5 percent; p = 0.22), nor did the rates of cardiovascular disease differ (1.0 percent vs 1.4 percent; p = 0.047). ), respiratory SAEs (0.4 percent each), gastrointestinal SAEs (0.4 percent each), infection-associated SAE (0.4 percent vs 0.3 percent; p = 0.65), or infection-related SAE (1.5 percent vs 1.6 percent; p = 0.65) 0.75). Fatal SAEs occurred in a similar proportion of high-dose and standard-dose vaccine recipients (0.1 percent versus 0.2 percent). [n=8 vs 13]; p = 0.27). One recipient of the high-dose vaccine and four recipients of the standard dose experienced serious adverse reactions.
High-dose vaccines are approved for adults aged ≥65 years old in most countries, and for those
≥60 years in some countries,” said senior author and investigator Professor Tor Biering-Sørensen of the Center for Translational Cardiology and Real-Time Randomized Trials, University of Copenhagen, Copenhagen, Denmark.
However, only a few countries offer older adults a high-dose vaccine by default. Thus, higher-dose vaccines are not widely implemented despite accumulating evidence of additional protection against influenza infection and influenza-related morbidity compared to standard-dose vaccines. “
“[The DANFLU-1 trial] It hinted at benefits in morbidity and mortality with a high dose compared to a standard dose [flu vaccine]Hu Don. “Reductions in hospitalizations and all deaths from the high-dose vaccine were encouraging but require confirmation in a larger trial before directing potential clinical practice.”
The trial also demonstrated the feasibility of incorporating a randomized influenza vaccine trial into a routine Danish vaccination program as well as using administrative health records to collect data, Behring Sorensen said. He said the individual study visit and the use of health records to verify data reduced the burden on study participants and researchers.