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.