Relation between influenza vaccination and outpatient visits, hospitalization, and mortality in elderly persons with chronic lung disease

Background: Influenza Vaccine is underused in groups targeted for vaccinati on. Objective: To define the effects of influenza and the benefits of influenza Vaccination in elderly persons with chronic lung disease. Design: Retrospective, multiseason cohort study. Setting: Large managed care organization. Patients: All elderly members of a managed care organization who had a prev ious diagnosis of chronic lung disease. Measurements: Outcomes in vaccinated and unvaccinated persons for the 1993- 1994, 1994-1995, and 1995-1996 influenza seasons were compared after adjust ment for baseline demographic and health characteristics. All data were obt ained from administrative databases. Results: Vaccination rates were greater than 70% for each season. Among unv accinated persons, hospitalization rates for pneumonia and influenza were t wice as high in the influenza seasons as they were in the interim (non-infl uenza) periods. Influenza vaccination was associated with fewer hospitaliza tions for pneumonia and influenza (adjusted risk ratio, 0.48 [95% CI, 0.28 to 0.82]) and with lower risk for death (adjusted odds ratio, 0.30 [Cl, 0.2 1 to 0.43]) during the influenza seasons. It was also associated with fewer outpatient visits for pneumonia and influenza and for all respiratory cond itions. Conclusions: For elderly persons with chronic lung disease, influenza is as sociated with significant adverse health effects and influenza vaccination is associated with substantial health benefits, including fewer outpatient visits, fewer hospitalizations, and fewer deaths. Health care providers sho uld take advantage of all opportunities to immunize these high-risk patient s.