The aim of the study was to assess changes in asthma prevalence between 1994/1995 (study I) and 2001/2002 (study II). Standardized ISAAC questionnaire was used. Randomly assigned population of school children 6-7 and 13-14 yrs of age was surveyed in Kraków and Poznań.
Results: The prevalence of wheezing ever increased significantly in group 6-7 yrs of age from 25.5% to 28.6% in Krakow and from 17.3% to 27.6% in Poznań, respectively in study I and study II. The similar rise was found in group 13-14 yrs of age in Krakow from 14.6% to 21.6%, in Poznań from 17.1% to 22.2%. In both age groups and in both centers the number of children with established asthma diagnosis increased: in group 6-7 yrs of age in Krakow from 4.0% to 5.8%, in Poznań from 1.3% to 5.9%; in group 13-14 yrs of age in Krakow from 2.3% to 6.8%, in Poznań from 2.0% to 5.2%. Analysis of current symptoms (in the last year) confirmed increasing prevalence of wheezing, wheezing after exercise and night cough in Poznań in both age group, in Krakow only in older children. In younger children in Kraków significant difference concerned only wheezing after exercise. The most frequent symptom reported by children was nocturnal cough in the last year.
Conclusions: The prevalence of the asthma symptoms and established asthma diagnosis increased during last 7 years. However significant number of children presenting asthma symptoms remains still underdiagnosed.