Objective: To determine the prevalence of atopic dermatitis and associated symptoms in schoolchildren from the city of São Paulo in 1996 and 1999.
Methods: The International Study of Asthma and Allergies in Childhood (ISAAC) written questionnaire was applied to the parents of 6 to 7-year-old children in 1996 and 1999 (3,005 in 1996 and 3,033 in 1999) and to 13 to 14-year-old adolescents (3,008 in 1996 and 3,487 in 1999). In the ISAAC, the option eczema ever indicates that a diagnosis of atopic eczema was made by a physician at least once in the subject's life. This was used to define "medical diagnosis" in the present study. The concomitant report of lesions in the last year in characteristic places constitutes the "combined criterion" for the diagnosis of atopic eczema and was also employed in the present study. Data were analyzed using the Epi-Info 6.0 software.
Results: In the 6 to 7-year-old group, there was a significant decrease in the number of "medical diagnoses" of atopic eczema in 1999 (11.4%) in comparison to 1996 (13.2%). The increase in the prevalence of "medical diagnoses" observed in 1999 among adolescents was not significant (14 vs. 15%). Considering the "combined criterion," there were no significant differences between 1996 and 1999 in either group (6.6% vs. 6.8% for 6 to 7 year-old children; 3.7% vs. 4.4% for adolescents).
Conclusions: Despite the increase in the prevalence of atopic diseases worldwide, we documented a reduction in the prevalence of "medical diagnoses" of atopic eczema in 6 to 7-year-old children. Nevertheless, atopic eczema remains as a relevant disease in the pediatric population.