Influenza immunization coverage and predictors in adults with diabetes in Madrid

Introduction: Using data from the Madrid City Health Survey 2004-2005 (ESCM), this study aims to: 1. Compare the coverage of influenza immunization among adults with diabetes versus those without diabetes. 2. Find the factors which determine a greater coverage among people with diabetes. Methods: We analyzed data from 1074 adults (age ≥16 years), of whom 358 were diabetic and 716 non-diabetic subjects, randomly selected as controls matched by age, sex and district. We considered the answer («Yes» or «No») to the question «¿were you vaccinated against influenza in the last campaign?» as the dependent variable. As independent variables we analyzed: a) sociodemographic characteristics; b) health-related variables, c) use of health services. Among vaccinated subjects, we also studied the reason for vaccination. Results: Among patients with diabetes, vaccine coverage in the last campaign was 60.1% (95%CI: 54.9-65) compared to 45.2% (95%CI: 41.6-48.9) among non-diabetics. After multivariate adjustment, the probability of being vaccinated was 1.7 times higher among diabetic than non-diabetic subjects [OR (95% CI:1.24-2.33)]. Among diabetics, vaccination coverage increased with age, in people with a lower education level, with a worse perception of health and among those suffering from other chronic diseases. Most people with diabetes who lived in Madrid and answered they had been vaccinated (94.7%), did so after «recommendation by the doctor or nurse». Conclusions: Despite the proven effectiveness of the flu vaccine and the fact that it is recommended for diabetics, vaccination coverage among adults with diabetes still remains below desirable levels, and therefore it is necessary to implement strategies to improve the use of the influenza vaccine among these patients.