Asthma and allergic rhinitis co-morbidity: a cross-sectional questionnaire study on adolescents aged 13-14 years.

Aims: There is scarce epidemiological population-based data on the prevalence of asthma and allergic rhinitis (AR) co-morbidity in adolescents. The aim was to verify asthma and AR prevalence rates in order to emphasise asthma/AR co-morbidity.

Methods: Cross-sectional study using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire in adolescents aged 13-14 years, chosen randomly from public schools in Belo Horizonte, Brazil.

Results: A total of 3262 students were identified, 3083 (47.3% males) of whom completed the questionnaire (response rate 94.7%). The prevalence of symptoms related to asthma and AR co-morbidity was 8.4% (95% CI, 8.09-10.25). Among asthmatic adolescents, symptoms of AR were reported in 46.5% (95% CI, 42.60-52.08%).

Conclusions: There is a high prevalence of adolescent asthma and AR co-morbidity in this area of Brazil. This co-morbidity is an important health issue that requires strategic application of primary health care facilities to achieve adequate control of both asthma and allergic rhinitis.