Prevalence and geographic variations in asthma symptoms in children and adolescents in Galicia (Spain).

OBJECTIVES To determine the prevalence and geographic variations of the symptoms associated with asthma in Galician children and adolescents. POPULATION AND METHODS A cross-sectional epidemiological study following ISAAC (International Study of Asthma and Allergies in Childhood) methodology, and using a written questionnaire distributed in schools. The study sample included 10,371 6-7 year-old children and 10,372 13-14 year-old adolescents, all of them from Galician Health Areas. A logistic regression model was used to analyse geographic variations. RESULTS In the 6-7 year-old group, wheezing in the last 12 months varied from 11.4% (Santiago) to 15.7% (Vigo) and in the adolescents varied from 8.8% (Ourense) to 18.8% (Vigo). The distribution by gender showed a predominant significance in 6-7 year-old males (P<.001), and near to be statistically significant in 13-14 year-old females (P=.08). The risk (odds ratio [OR]) of wheezing in the last 12 months in the area with highest prevalence in comparison with the area of lowest prevalence was 1.45 (95% Confidence Interval [CI], 1.12-1.88) for children and 2.39 (95% CI, 1.82-3.13) for adolescents. The estimated prevalence of asthma in the Autonomous Community of Galicia was 13.6% in younger children and 12.2% in adolescents. CONCLUSIONS The prevalence of wheezing in the last 12 months in the different areas of Galicia is considerably higher than the rest of Spanish ISAAC cities in the 6-7 years group and very similar in the 13-14 years group, except in Vigo where it is considerably higher. We found a clearly defined geographic pattern in the adolescent group, with higher prevalences in coastal areas than in the interior.