Factors associated with adherence to influenza vaccination among non-institutionalized elderly in São Paulo, Brazil

The objectives of this study were to estimate influenza vaccination coverage in the elderly and identify factors associated with vaccination uptake. A cross-sectional population-based study was conducted with data collected in 2006 by the Health, Well-Being, and Aging study. The sample consisted of 1,399 elderly in the city of São Paulo, Brazil. The association between vaccine uptake and independent variables was assessed with prevalence ratios, estimated by Poisson regression. Self-reported vaccination was 73.8%. In the final explanatory model, influenza vaccination was associated with older age, presence of chronic diseases, and use of health care in the previous year. A negative association was observed with hospitalization during the previous year. The study concludes that it is necessary to encourage vaccination of elderly less than 70 years of age and those without chronic diseases, as well as to orient health professionals to expand coverage in groups with lower uptake during vaccination campaigns.