IS IMMUNIZING ALL PATIENTS WITH CHRONIC LUNG-DISEASE IN THE COMMUNITYAGAINST INFLUENZA COST-EFFECTIVE - EVIDENCE FROM A GENERAL-PRACTICE BASED CLINICAL PROSPECTIVE COHORT STUDY IN UTRECHT, THE NETHERLANDS

Study objective-There is little information on the potential benefit o f immunising all patients with chronic lung disease in the community a gainst influenza. The clinical effectiveness and economic benefit was established of the influenza vaccination programme in a general practi ce based cohort of adult patients with chronic lung disease followed u p during the 1995/96 influenza A epidemic. Design-A prospective cohort study from October 1995 to March 1996. Setting-The study was undertak en in the Utrecht General Practices Network with six large group pract ices, covering a total population of approximately 50 000 patients in the Netherlands. Patients-Computerised medical records of 1696 patient s with chronic lung disease aged over 18 years with an indication for vaccination according to the Dutch GP guidelines were reviewed. Main r esults-The overall attack rate of any complication, including all caus e death, low respiratory tract infection, and acute cardiac disease wa s 15%. Exacerbations of lung disease were most frequent (13%). Death, pneumonia, and acute cardiac disease were mainly limited to patients g reater than or equal to 65 years. No effectiveness of the immunisation programme could be established in patients 18-64 years (n=1066), afte r controlling for baseline prognosis in multivariable logistic regress ion analysis. In vaccinees greater than or equal to 65 years (n=630), the occurrence of any complication was reduced by 50% (95% CI 17, 70%) . The economic benefit was estimated at pound 50 per elderly vaccinee. Conclusions-This study suggests that in the Netherlands immunisation of elderly patients with chronic lung disease against influenza is eff ective and cost-saving, hence these patients should be given high prio rity. More, preferably experimental, studies are needed to establish w hether adult lung patients under 65 years in the community will also b enefit from vaccination.