The additive benefits of influenza and pneumococcal vaccinations during influenza seasons among elderly persons with chronic lung disease

Uncertainty regarding the benefits of pneumococcal vaccination may contribu te to the under use of this vaccine. The present study was conducted to cla rify the benefits of influenza and pneumococcal vaccinations during 3 influ enza seasons among elderly persons with chronic lung disease. All elderly m embers of a large managed care organization with a prior diagnosis of chron ic lung disease were included in a cohort that was followed over three infl uenza seasons (1993-1994, 1994-1995, and 1995-1996). Data obtained from the administrative data bases of the health care organization included baselin e demographic and health characteristics, influenza vaccination status for each season, date of pneumococcal vaccination, and outcomes for each season including hospitalization for pneumonia and death. Cox proportional hazard s regression and Poisson regression with repeated measures were used to com pare the risk of outcomes among vaccinated and unvaccinated persons while c ontrolling for covariates and confounders. During the three influenza seaso ns, influenza vaccination alone was associated with a 52% reduction (95% CI 18-72) in hospitalizations for pneumonia and a 70% reduction (95% CI 57-89 ) in death. Pneumococcal vaccination alone during the three influenza seaso ns was associated with a 27% reduction (95% CI 13-52) in hospitalizations f or pneumonia and a 34% reduction (95% CI 6-54) in death. Both vaccinations together demonstrated additive benefits. When both vaccinations had been re ceived, there was a 63% reduction (95% CI 29-80) in hospitalizations for pn eumonia and an 81% reduction (95% CI 68-88) in death versus when neither ha d been received. These findings suggest pneumococcal vaccination is associa ted with substantial benefits for elderly persons with chronic lung disease . Published by Elsevier Science Ltd.