Increase in prevalence of rhinoconjunctivitis but not asthma and atopic eczema in teenagers.

OBJECTIVE

We sought to assess changes in the prevalence of asthma and other allergic diseases in schoolchildren of Curitiba between 1995 and 2001.

METHODS

Schoolchildren (aged 13-14) were evaluated by a self-reported written questionnaire of ISAAC protocol for symptoms of asthma and allergic diseases. The diagnoses of asthma, rhinoconjunctivitis and atopic eczema were considered according to the ISAAC protocol. Probable asthma was considered: more than 4 attacks of wheezing in the last 12 months; 1 to 3 attacks of wheezing in the last 12 months with dry cough at night, and/or with sleep disturbance due to wheezing, and/or with wheezing after exercise. The data obtained in 2001 were compared with the data obtained in 1995 for the same age group.

RESULTS

We evaluated 2,946 schoolchildren in 1995 and 3.628 in 2001. The prevalence of symptoms of asthma, probable asthma, rhinoconjunctivitis and eczema in 1995 and 2001 was 18.4% and 18.7%, 11.6% and 12.4%, 14.2% and 17.2%, 3.8% and 3.7%, respectively. There was a 23.7% increase in the prevalence of rhinoconjunctivitis symptoms (p < 0.05).

CONCLUSIONS

The prevalence of symptoms of asthma, probable asthma and eczema did not change over the past 6 years but a significant increase of the rhinoconjunctivitis symptoms was detected.