Gender influence in influenza vaccine uptake in Spain: time trends analysis (1995-2006).

This study aims to analyze gender differences in influenza vaccine coverage and predictors of vaccine uptake in Spain from year 1995 to 2006. We used data obtained from the Spanish National Health Surveys (NHSS) conducted in 1995, 1997, 2001, 2003 and 2006. Only subjects for whom the vaccine was recommended in Spain (age >or=65 years and <65 years with an associated chronic condition) during the entire study period were analyzed. Influenza vaccination status was self-reported. Independent variables included: year of survey, age, marital status, educational level, size of town, physician visits and chronic conditions. The study population included 26,653 (15,973 women and 10,680 men) individuals and 54.9% (CI 95% 54.3-55.5) were vaccinated. Vaccination coverage was higher among men than women in each and all of the NHSS analyzed. Positive predictors of vaccine uptake were the same among women and men including: higher age, being married, lower educational level, "Physician visits in last four weeks"; and the presence of associated chronic condition. Time trends 1995/1997-2006 showed that the coverage has improved for women (OR 1.12 CI 95% 1.09-1.16) and men (OR 1.11 CI 95% 1.06-1.15). Over the whole study period men had 12% greater probability of having received the vaccine. We conclude that in Spain there are significant gender differences in influenza vaccine uptake with lower coverage among women. These differences have remained throughout all years studied. We suggest that possible explanations for the lower uptake among women could include less social support, differences in the health status and provider bias.