Prevalence of asthma and rhinitis symptoms among children living in Coimbra, Portugal.

Asthma is the most common chronic disease in pediatrics. Most data on the prevalence of childhood allergic diseases come from the International Study of Asthma and Allergies in Childhood (ISAAC) phase II held in 1995 and phase III from 2002. ISAAC created a methodology for studying two age groups 6--7 and 13--14 years old. In 2002, according to the data gathered in the phase III of ISAAC, the prevalence of asthma among Portuguese children from 6 to 7 years old was 9.4%, 29.1% for rhinitis and 28.1% for wheezing. In the last decade, little information on the prevalence of childhood asthma and rhinitis in Portugal has been documented, and to the best of our knowledge, none in Coimbra. In 2002, 5 centers from 5 Portuguese cities joined the ISAAC project: Lisbon, Oporto, Coimbra, Portimão and Funchal. The Coimbra research center only studied 13--14 years old adolescents. The district of Coimbra, with a total area of 3974 km, is located in central Portugal and has 434,311 inhabitants. Coimbra is the biggest city in the central region, and the 6th largest in Portugal. The most recent published data on childhood asthma prevalence in Portugal come from the Lisbon 2008 study where the prevalence of asthma, allergic rhinitis and wheezing was 5.6%, 43.0% and 43.3%, respectively, and from