Effectiveness of influenza vaccination on in-hospital death in older adults with respiratory diseases

ABSTRACT

Influenza vaccination is associated with lower risk of hospitalization outcomes among older adults with respiratory diseases, but there is limited evidence by disease subtypes and patients’ characteristics. This study included patients aged ≥60 years hospitalized for respiratory diseases from the Beijing Urban Employee Basic Medical Insurance database during 6 influenza seasons. Vaccination status was assessed by linking with the Beijing Elderly Influenza Vaccination database. Multi-variable logistic regression was performed to calculate effect estimates. After adjusting for measured and unmeasured confounders, influenza vaccination was associated with a lower risk of in-hospital death among older adults hospitalized for respiratory diseases (odds ratio [95% confidence interval], 0.70 [0.62–0.80]). The protective association was observed among patients with chronic obstructive pulmonary disease (0.67 [0.47–0.98]) as well as those with pneumonia or influenza (0.77 [0.64–0.93]). The protective association was stronger in younger patients (0.59 [0.43–0.81] for <75 and 0.72 [0.63–0.83] for ≥75) and those with fewer comorbidities (0.49 [0.16–1.62] for 0, 0.65 [0.50–0.86] for 1–2, and 0.72 [0.63–0.83] for ≥3 comorbidities). Influenza vaccination was associated with lower risk of in-hospital death among older patients hospitalized for respiratory diseases, with stronger associations in patients with younger age and fewer comorbidities.

Plain Language Summary

We found that influenza vaccination was associated with lower risk of in-hospital death among older adults hospitalized for respiratory diseases. The associations were stronger in patients with younger age and fewer comorbidities. The study suggested that, in addition to prevent influenza itself, influenza vaccination may also prevent in-hospital death among patients with respiratory diseases.

KEYWORDS:

• Influenza vaccination
• in-hospital death
• older adults
• pneumococcal vaccination
• respiratory disease

Acknowledgement

We thank 444 vaccination clinics for their contributions to the acquisition of the immunization data. This study was exempted from the Institutional Review Board (IRB) approved by the Ethics Committee of Beijing Center for Disease Control and Prevention. The need for informed consent was also waived by the IRB.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author’s contributions

M Lv and YH had full access to the data.

RZ, SW, and YH conducted data analysis and are responsible for accuracy of the results and the decision to submit for publication.

All authors were involved in study design, conduct, long-term follow-up, review and coding of disease events, interpretation of the results, or writing the report.

Additional information

Funding

This work was supported by grants from Natural Science Foundation of Beijing (19L2056), Beijing Municipal Health Commission, Pilot Projects of Public Welfare, Development and Reform for Medical Research Institutes in Beijing (grant number 2018-1), and the Capital Health Research and Development of Special (2022-2G-3017). Dr Pang acknowledges findings from the Peking University Medicine Fund of Fostering Young Scholars’ Scientific & Technological Innovation (BMU2022RCZX022), the Fundamental Research Funds for the Central Universities, and the Peking University Start-up Grant (BMU2022PY014). The study sponsors had no role in study design; collection, analysis, and interpretation of data; writing the report; and the decision to submit the report for publication.