Influence of prior pneumococcal and influenza vaccination on outcomes of older adults with community-acquired pneumonia

Abstract

Objectives: To determine whether prior pneumococcal and seasonal influenza vaccination improves outcomes in older adults hospitalized for community-acquired pneumonia (CAP).

Design: Prospective, observational, multicenter study.

Setting: Five public hospitals providing universal free care to the whole population in three Spanish regions.

Participants: Individuals aged 65 and older admitted to the hospital with CAP through the emergency department.

Measurements: Pneumococcal and influenza vaccination status. The primary study outcomes were intensive care unit (ICU) admission, length of hospital stay (LOS), and overall case-fatality rate. Outcome variables of individuals vaccinated with both vaccines were compared with outcomes of those who were unvaccinated.

Results: Two hundred thirty-eight individuals had received 23-valent pneumococcal polysaccharide vaccine and seasonal influenza vaccination and were compared with 195 unvaccinated individuals. No differences were found with respect to combined antibiotic therapy between groups (38.0% vs 39.7%; P = .80). Similar percentages of vaccinated and unvaccinated individuals required ICU admission (7.2% vs 8.2%; P = .69). Mean LOS was significantly shorter in vaccinated individuals (9.9 vs 12.4 days; P = .04). Overall case-fatality rates were similar in both groups (5.9% vs 5.1%; P = .73). After adjustment, LOS, risk of ICU admission, and overall case-fatality rate were not associated with prior pneumococcal and seasonal influenza vaccination.

Conclusion: The clinical outcomes of vaccinated older adults hospitalized with CAP were not better than those observed in unvaccinated individuals.