Influenza Vaccination Reduces Mortality and Readmissions in Heart Failure Patients: Study

A recent study published in The Lancet journal found that providing free influenza vaccination significantly lowered all-cause mortality and hospital readmissions compared to usual care, with fewer adverse events reported

The study was designed to assess whether hospital-based flu vaccination which could improve outcomes among adults with moderate to severe heart failure. This research compared 2 groups: hospitals offering point-of-care influenza vaccination (the intervention group) and hospitals following usual care (the control group). The patients in control hospitals were informed about vaccination availability at community clinics but had to pay out-of-pocket, as per standard practice.

Each participating hospital was randomized yearly, ensuring balanced distribution across regions and influenza seasons. Eligible participants were adults aged 18 years or older diagnosed with New York Heart Association (NYHA) class III or IV heart failure who had no contraindications to influenza vaccination.

All enrolled patients received standard heart failure management and were followed up for a year, with visits at 1, 3, 6, and 12 months after hospital discharge. The trial’s primary endpoint was a composite measure combining all-cause mortality and hospital readmission within 12 months, excluding events within 30 days of discharge and, for northern sites, during the summer months.

The results revealed that patients vaccinated before discharge had notably lower rates of the combined primary outcome when compared to the patients receiving usual care. The benefit was consistent across regions and age groups, underscoring the robustness of the effect.

Hospitals in the vaccination arm reported a significant relative reduction in the composite outcome, with approximately 8–10 fewer deaths or readmissions per 100 patients when compared to usual care. Subgroup analysis showed particularly strong effects among patients over 65 years and those with multiple comorbidities. The vaccine uptake rate in the intervention group exceeded 85%, while in the control group it remained below 20%, which highlighted the success of hospital-based delivery.

Secondary measures, including individual rates of mortality and readmission, also favored the vaccination strategy, though the magnitude varied by region and influenza intensity. Also, no increase in adverse events was reported, which confirming the safety of vaccine in this vulnerable population.

Overall, this study suggests that embedding free vaccination services in hospital discharge protocols could be a highly effective and scalable intervention to improve cardiovascular outcomes nationwide.

Source:

Anderson, C. S., Hua, C., Wang, Z., Wang, C., Jiang, C., Liu, R., Han, R., Li, Q., Shan, S., Billot, L., Macintyre, C. R., Patel, A., Zhang, H., Ma, C., Dong, J., & Du, X. (2025). Influenza vaccination to improve outcomes for patients with acute heart failure (PANDA II): a multiregional, seasonal, hospital-based, cluster-randomised, controlled trial in China. Lancet, 406(10507), 1020–1031. https://doi.org/10.1016/S0140-6736(25)01485-0