[Change of nonspecific bronchial responsiveness and other indices of asthma severity in groups of patients treated with beta2-adrenomimetics "on demand". Test of correlation].

We studied 21 subjects with clinically stable atopic asthma. Our aim was to evaluate the relationship between the changes of the nonspecific bronchial responsiveness and spirometry, PEF- and laboratory parameters during 6 weeks observations. The spirometry values (FEV1%VC, MEF50), measurements of the provocative concentration of histamine causing a 20% fall in FEV1 (PC20H, according to Cockcroft) and analysis of blood eosinophil count and total IgE titre were performed twice, at 6 week interval. The studied patients recorded daily their symptoms and the number of puffs of betamimetics. They also measured daily their morning and evening PEF. We found any statistically significant changes during the study in evaluated parameters (t-Test). There was a degree of correlation between the symptom score and the use of bronchodilators. At the same time there were no trends in PC20H and the symptoms score, B2-agonist use, bronchial obstruction (FEV1%VC, MEF50) or mean amplitude of PEF. We conclude, that in the clinical assessment of asthma nonspecific bronchial responsiveness seems to be an independent variable.