Determinants of influenza vaccination among the adult and older Italian population with chronic obstructive pulmonary disease: a secondary analysis of the multipurpose ISTAT survey on health and health care use.

We analyzed seasonal flu vaccination rates among the Italian population suffering from Chronic Obstructive Pulmonary Disease (COPD) in order to identify socio-demographic and clinical determinants for vaccination. We used data from the survey "Health and health care use in Italy", which interviewed 5,935 persons (age 15 - 102 years) suffering from COPD in the period 2004-2005. For each respondent, information on socioeconomic and health conditions, smoking status and patterns of health care utilization were retrieved. After bivariate analysis, we used two multilevel regression models to assess determinants of vaccination among the adult and the older Italian population. Overall 30.5% of adults (N=670) and 74.8% (N=2,796) of older people reported being vaccinated against seasonal flu. After controlling for potential confounders, older age increases the odds of vaccine uptake. Single marital status among the older people, smoking and not having contact with GPs in both age groups, are factors associated with non vaccination. Higher-educated elderly are less likely to be vaccinated, while coverage is higher among the wealthier adults. Vaccine coverage among adults with COPD in Italy remains low, especially among those with no comorbidities, and aged less than 44 years. It is only in older age that vaccination rates increase substantially. We found several risk factors for non vaccination, such as smoking, single marital status, and not having contacts with GPs, which should be considered in developing strategies to increase the coverage of influenza vaccine among people with COPD in Italy.