[Population Based Studies on the Incidence of Chronic Respiratory Symptoms and Lung Function in Children from Krakow]

The epidemiologic study has been carried out in the sample of 1048 schoolchildren at the age of 11 years in order to assess the impact of various chronic respiratory symptoms on lung function. The symptoms included chronic dry cough, chronic phlegm, attacks of cough at nights, breathlessness, wheezing independent from respiratory infections or colds, attacks of wheezing at nights, and attacks of dyspnea with wheezing. Lung function was measured by the following spirometric indices: FEV1/FVC%, FEV1, FEF25-75% and PEFR. Multiple regression analysis showed strong statistical inverse relationship between FEV1/FVC% and FEF25-75% and attacks of wheezing at night and attacks of dyspnea with wheezing or asthma diagnosed by physician. The separate analysis performed in the subsample of children without asthma and asthmatic symptoms (attacks of wheezing at night and attacks of dyspnea with wheezing) found out that only chronic dry cough was related significantly to the lower values of FEV1 and PEFR in the children.