Influenza immunization and mortality among diabetic Medicare beneficiaries in West Virginia.

This study estimated the increased risk of death among Medicare beneficiaries with diabetes in West Virginia who do not receive influenza beneficiaries with diabetes. Medicare beneficiaries with diabetes who did not have claims for influenza vaccination had approximately a 1.7-fold risk of death during a subsequent influenza season, compared with those with a vaccination. This risk was observed in all age and sex subgroups, and was changed very little by adjustment for comorbidity. The adjusted odds ratio for death in the vaccinated group (compared with the unvaccinated group) during the 1996-97 influenza season was 0.639 (95% confidence interval 0.565-0.722); in 1997-98 it was 0.601 (95% confidence interval 0.527-0.687). West Virginia Medicare beneficiaries with diabetes are at a significantly increased risk of death during an influenza season if they do not have prior claims for influenza vaccination.