Influenza vaccination in subjects with alpha1-antitrypsin deficiency

BACKGROUND: Influenza vaccination is recommended for all subjects with COPD, including alpha(1)-antitrypsin deficiency (AATD), but immunization practices are below US national goals. Influenza vaccination practices and their relation to respiratory outcomes in AATD are unknown. METHODS: Nine hundred thirty-nine subjects with AATD were followed up prospectively by monthly telephone interviews during the 2003 to 2004 influenza season. Vaccination status, exacerbation rates, and health-care utilization were documented. Residence zip codes were used to group subjects as living in high or low influenza-like illness (ILI) prevalence areas according to published Centers for Disease Control and Prevention data for the same influenza season. RESULTS: Overall, 81.6% of subjects received influenza vaccination, with no differences noted by gender, age (median age 52 years), Global Initiative for Chronic Obstructive Lung Disease stage, or ILI prevalence area. No significant differences were noted in the overall acute exacerbation rates using two different criteria between vaccinated and unvaccinated subjects (mean, 1.5 +/- 1 exacerbations per subject). Similarly, no differences were noted in either the severity of exacerbations or the monthly exacerbation rates between the two groups. Unvaccinated subjects had more unscheduled physician visits than vaccinated subjects, but there were no significant differences in scheduled visits, emergency department visits, or hospitalizations between the two groups. Older age (> 60 years) or residence in a high ILI prevalence area had no effect on outcomes. CONCLUSION: Subjects with AATD in the United States receive adequate influenza vaccination regardless of age. However, we did not observe a significant impact of the vaccination on disease exacerbations and other respiratory outcomes during the 2003 to 2004 influenza season.