Prevalence and risk factors for asthma in Poland: results from the PMSEAD study.

BACKGROUND: The prevalence of asthma depends on both hereditary and environmental factors. Knowledge of the effects of environmental and congenital factors on the frequency of occurrence of asthma may provide important clues to its pathogenesis and prevention. OBJECTIVES: The Polish Multicentre Study of Epidemiology of Allergic Diseases was designed to obtain estimates representative of the entire Polish population to assess asthma prevalence and risk factors. METHODS: Thirty-three areas were selected in 11 regions of Poland. Epidemiologic diagnoses of asthma were verified by a single recognized expert in each region on the basis of collected data as well as available medical documentation, in accordance with the 1997 guidelines of the Global Initiative for Asthma. Ambient air concentrations of sulfur dioxide and suspended particulates (black smoke) were measured directly or estimated by statistical modelling. RESULTS: Results were obtained for asthma in 16 238 subjects, including 3268 children (aged 3 to 16 years) and 12 970 adults (17 to 80 years). The overall prevalence of asthma was 8.6% (95% confidence interval [CI], 7.7%-9.6%) among children and 5.4% (95% CI, 5.0%-5.8%) among adults. Several risk factors for asthma were identified: family history of asthma, black smoke, residential exposure to traffic-related air pollution in both children and adults, and damp or overcrowded housing in adults. No statistically significant association was observed for passive smoking in the home, use of gas stoves, pet ownership, or exposure to ambient air pollution with sulfur dioxide. CONCLUSION: Our results show that the prevalence of asthma is associated with several host and environmental factors in the Polish population.

Long-term effects on health of air pollution in children.

A literature review is presented showing the role and relative importance of various endogenous and exogenous factors, classified into predisposing, provoking and facilitating factors, in the development of Chronic Non-Specific Respiratory Diseases (CNSRD) in children. The review is also based on the results of own clinical studies and a longitudinal epidemiological study. In total, 12,708 children were examined in the epidemiological study, including a cohort of 1,303 children examined three times. In the analysis of the frequency and the dynamics of respiratory symptoms, significant contribution of various factors was demonstrated, including history of obstructive bronchitis in the first year of life, frequency of respiratory infections in early childhood, passive tobacco smoking, socioeconomic conditions such as education of parents, day nursery and kindergarten attendance and living in an area with high levels of air pollution.

Dynamics of respiratory symptoms and lung function in epidemiological long-term study in children.

Dynamics of respiratory symptoms and past respiratory diseases were studied in a cohort of children examined twice. Relative risk of having the same symptom/disease after three years was calculated, producing a ranking of the symptoms, believed to reflect their epidemiological significance. An independent ordering of the symptoms was obtained, based on the relative risk of lower airways illness in a group of children followed-up for two years. In the analysis of lung function dynamics, practical independence of PEFR measurements and respiratory symptoms was confirmed.

[Usefulness of the PEFR (peak expiratory flow rate) measured with Wright's apparatus for the diagnosis of chronic respiratory tract diseases in children]. / Ocena przydatnosci PEFR--szczytowego przeplywu wydechowego oznaczonego aparatem Wrighta do badan przewleklych chorób ukladu oddechowego u dzieci.

The measurement error was estimated in 5 peak flow meters of Wright serving for measurements of peak respiratory flow rate in children. The estimation was carried out by two methods: 1) comparing the agreement of measurements with the apparatuses connected to steady flow generator. 2) by means of a biological experiment making possible estimation of the apparatuses as well as the subjects carrying out the measurements. The first method, although disagreeing with the design of the apparatus, makes possible sufficiently accurate estimation, is simple, rapid. The second method demonstrated that the only source of differences between the measurements were instruments and not the personnel carrying out the measurements.

[Evaluation of the PEFR (peak expiratory flow rate) measurement error in using Wright's apparatus]. / Ocena bledu pomiaru PEFR--szczytowego przeplywu wydechowego, oznaczonego aparatem Wrighta.

The usefulness of peak respiratory flow rate (PEFR) was evaluated for investigating chronic respiratory diseases in children. The investigations were carried out in 1088 children aged 8-10 years. The reproducibility of the test, the accuracy confirmed by the results of medical, laryngological, radiological, biochemical investigations and respiratory function tests, as well as the cost of testing, easiness of test application in mass examinations and acceptance by the children were analysed. In the light of these investigations PEFR is regarded to be a very useful simple test which should be widely introduced. It was found also that it is one of the simplest function tests permitting quantitative evaluation of the degree of reduction of ventilation ability of the lungs in children.