A high-dose vaccine reduced hospital admissions for flu or pneumonia by nearly 9% among older individuals with chronic respiratory conditions like asthma and COPD.
RT’s Three Key Takeaways:
- Reduced Hospitalization Risk: A high-dose influenza vaccine reduced hospital admissions for flu or pneumonia by 8.8% in adults aged 65 and older with chronic lung disease compared to a standard-dose vaccine, according to data presented at the European Respiratory Society Congress.
- Targeted Respiratory Cohort: The pooled analysis evaluated nearly 32,000 older individuals diagnosed with chronic respiratory conditions, including chronic obstructive pulmonary disease, asthma, and emphysema.
- Broader Clinical Protection: Beyond pneumonia and influenza, the high-dose formulation also reduced hospitalizations for cardiorespiratory disease and all-cause admissions, supporting updated immunization strategies for high-risk older adults.
Older adults with chronic lung disease who receive a high-dose influenza vaccine experience a lower risk of hospitalization for flu or pneumonia compared to those who receive a standard-dose vaccine, according to combined results from two clinical trials presented at the ERS 2026.
“Flu can be particularly serious for older people with chronic lung disease, such as asthma and COPD. They are more likely to develop complications, including pneumonia, worsening of their existing lung disease, and hospitalization,” said Dr Lisa Steen Duus, researcher from Gentofte Hospital in Copenhagen, Denmark. “Although high-dose flu vaccines are designed to produce a stronger immune response in older adults, there has been limited randomized evidence specifically showing whether they provide better protection against serious illness in people with chronic lung disease. We therefore wanted to investigate whether a high-dose vaccine could reduce hospitalizations in this particularly vulnerable group.”
Evaluating High-Risk Respiratory Cohorts
The research pooled data from two randomized controlled trials comparing high-dose and standard-dose influenza vaccines in adults aged 65 and older, according to the presentation. One trial took place in Denmark over three influenza seasons (2022-23, 2023-24, and 2024-25), while the other was conducted in Galicia, Spain, across two seasons (2023-24 and 2024-25).
In the pooled study, investigators focused on 31,976 participants diagnosed with chronic lung diseases, representing just under 7% of the total 466,320 trial participants. Qualifying conditions included asthma, bronchiectasis, bronchitis, COPD, cystic fibrosis, emphysema, interstitial pulmonary disease, lung transplantation, respiratory tuberculosis, and sarcoidosis.
Approximately half of the participants were randomly assigned to receive a standard-dose vaccine, while the remaining half received a high-dose flu vaccine containing four times the active ingredient designed to stimulate immune response. Researchers tracked participants from 14 days after vaccination through the end of the European influenza season the following May.
Measurable Reductions in Acute Admissions
Trial data revealed that the high-dose flu vaccine reduced hospital admissions for influenza or pneumonia by 8.8% compared with the standard-dose vaccine. Additionally, the high-dose vaccine reduced hospital admissions for cardiorespiratory disease, as well as all-cause hospitalizations.
“Being hospitalized creates a considerable burden on patients, families and healthcare systems, so even a modest reduction could have meaningful public health benefits. For that reason, these results support considering high-dose flu vaccines for older adults, including those with chronic lung disease, when developing vaccination recommendations,” said Dr Duus, researcher from Gentofte Hospital.
Experts not involved with the study highlighted the clinical significance for vulnerable respiratory populations facing seasonal viral surges.
“This research combines the results of two large and well-run studies comparing the standard-dose flu vaccine with a high-dose flu vaccine in people aged 65 and above. Researchers have looked specifically at people on the trial who had also been diagnosed with a lung disease, such as COPD or asthma. Their analysis shows that a high-dose flu vaccine could be even more beneficial in this group,” said Professor Thomas Wilkinson, chair of the European Respiratory Society’s Group on Respiratory Infections and Immunology at University of Southampton, UK.
