Background: Influenza and pneumococcal vaccination are recommended in patients with chronic obstructive pulmonary disease (COPD). A recent study from Tayside found a reduced risk of all cause mortality with vaccination in COPD patients.
Objectives: We used The Health Improvement Network (THIN) database to test this hypothesis in a different data source.
Methods: We searched the THIN database for patients with COPD. Vaccination status against pneumococcus and their annual influenza vaccination status were determined. Mortality rates were calculated in the periods December-March, April-November. Relative risks for the effect of vaccination on all cause mortality were estimated by Poisson regression, adjusting for age, sex, year and serious co-morbidities.
Results: We found 177,120 patients with COPD, mean age of 65 years, with an average of 6.8 years follow up between 1988 and 2006. Vaccination rates against influenza rose from <30% prior to 1995 to >70% in 2005 among patients aged 60 years or more. The cumulative vaccination rate against pneumonia rose from almost zero to 70% in patients aged 70 years or more over the same period. For all cause mortality the adjusted relative risks (95% CI) associated with influenza vaccination were 0.59(0.57-0.61) during the influenza season and 0.97(0.94,1.00) outside the season in patients not vaccinated against pneumonia, and 0.30(0.28,0.32) and 0.98(0.96,1.11) respectively in patients vaccinated against pneumonia. The relative risk associated with pneumococcal vaccination was greater than 1 at all times of the year.
Conclusions: Influenza but not pneumococcal vaccination was associated with a reduced risk of all cause mortality in COPD.