Prevalence of and factors associated with underdiagnosis of pediatric asthma in Batumi, Georgia.

BACKGROUND AND OBJECTIVE: A recent survey in Batumi, Georgia showed a low prevalence of asthma in children (1.8%). A potential explanation is underdiagnosis of asthma. To investigate this, we conducted a follow up to the survey with the objective of estimating the level of childhood asthma underdiagnosis and to describe factors related to it. METHODS: Subjects included 437 survey participants who had a history of asthma-like symptoms and no diagnosis of asthma. All children underwent clinical examination (spirometry, skin prick tests, FeNO measurement) to identify new cases of asthma. The distribution of host and environmental factors was compared between the group with newly identified asthma and a group of 59 children with previously known asthma (diagnosed asthma). RESULTS: Clinical investigation identified 107 cases of undiagnosed asthma. The corrected asthma prevalence estimate was 5.1% (95%CI: 4.4%-5.9%) suggesting that 65% of asthma cases were undiagnosed. Compared to children with diagnosed asthma, children with undiagnosed asthma were younger (8.2±1.6 vs. 9.3±2.1; p=0.0005), had less frequent history of allergic disorders (38.3% vs. 64.4%; p=0.001), and a lower prevalence of parental asthma (1.8% vs. 8.4%; p=0.04). The groups did not differ in terms of environmental characteristics except for more exposure to passive smoking in the undiagnosed asthma group (p=0.01). Multivariate analysis confirmed results of simple analyses. CONCLUSION: In Batumi, 65% of children with asthma remain undiagnosed. Older age of a child, coexisting allergic disorders, and parental asthma seem to facilitate diagnosis. Implementation of current diagnostic guidelines should improve diagnostic accuracy of pediatric asthma in Batumi.

Respiratory hypersensitivity reactions to NSAIDs in Europe: the global allergy and asthma network (GA2 LEN) survey.

BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most prevalent drugs inducing hypersensitivity reactions. The aim of this analysis was to estimate the prevalence of NSAID-induced respiratory symptoms in population across Europe and to assess its association with upper and lower respiratory tract disorders. METHODS: The GA2 LEN survey was conducted in 22 centers in 15 European countries. Each of 19 centers selected random samples of 5000 adults aged 15-74 from their general population, and in three centers (Athens, Munich, Oslo), a younger population was sampled. Questionnaires including questions about age, gender, presence of symptoms of asthma, allergic rhinitis, chronic rhinosinusitis, smoking status, and history of NSAID-induced hypersensitivity reactions were sent to participants by mail. Totally, 62 737 participants completed the questionnaires. RESULTS: The mean prevalence of NSAID-induced dyspnea was 1.9% and was highest in the three Polish centers [Katowice (4.9%), Krakow (4.8%), and Lodz (4.4%)] and lowest in Skopje, (0.9%), Amsterdam (1.1%), and Umea (1.2%). In multivariate analysis, the prevalence of respiratory reactions to NSAIDs was higher in participants with chronic rhinosinusitis symptoms (Odds Ratio 2.12; 95%CI 1.78-2.74), asthma symptoms in last 12 months (2.7; 2.18-3.35), hospitalization due to asthma (1.53; 1.22-1.99), and adults vs children (1.53; 1.24-1.89), but was not associated with allergic rhinitis. CONCLUSION: Our study documented significant variation between European countries in the prevalence of NSAID-induced respiratory hypersensitivity reactions, and association with chronic airway diseases, but also with environmental factors.

Prevalence of childhood asthma, rhinitis, and eczema in the Ternopil region of Ukraine--results of BUPAS study.

PURPOSE: The aim of the study was to estimate the prevalence of allergic diseases and symptoms in children of the Ternopil Region (Ukraine) and to explore their familial and environmental correlates. MATERIAL/METHODS: A cross-sectional study based on parental answers to a respiratory questionnaire based on ISAAC that included 4871 urban and rural children aged 6-14 years. Association of physician-made diagnoses and symptoms with environmental factors was examined by means of multivariate logistic regression. RESULTS: Increased risk of asthma (1.7%) was associated with urban residence (OR=1.8; p=0.04) and high parental education (OR=1.8; p= 0.02); spastic bronchitis (6.2%) with parental allergy (OR=1.3; p= 0.03); atopic eczema (6.2%) with younger age (OR=1.3; p=0.03), high parental education (OR=1.3; p=0.03), parental allergy (OR=1.4; p=0.02), tobacco smoke at home (OR=0.7; p=0.01) and household density (OR=0.6; p=0.001); diagnosis of unspecified allergic sensitization (11.8%) was related to high parental education (OR=1.2; p=0.03), parental employment (OR=0.8; p=0.02) and pets at home (OR=1.2; p=0.06). Symptoms of chest wheezing (11.5%) were related to tobacco smoke at home (OR=0.8; p=0.06). Attacks of dyspnea (7.3%) were related to parental allergy (OR=1.4; p=0.007), and type of heating (OR=1.7; p=0.04). Hay fever symptoms (5.7%) were related to younger age (OR=1.3; p=0,01) and urban residence (OR=2.0; p<0.0001). CONCLUSIONS: Except for asthma the prevalence of allergic diseases and symptoms as well as their correlates in children of Ternopil are similar to other estimates obtained in Eastern Europe. Low prevalence of asthma and relatively frequent occurrence of spastic bronchitis may suggest substantial underdiagnosis of childhood asthma.

Risk factors for asthma in school children--results of a seven-year follow-up.

The objective of the study was to evaluate the cumulative incidence of physician-diagnosed asthma over the period of 7 years, and to determine its host and environmental risk factors in children aged 7-9 years at the beginning of follow-up. The incidence of the disease was determined from answers to respiratory questionnaire on two occasions (in 1993 and 2000) in a group of 663 children aged 14-16 years in 2000. The data on host and environmental factors obtained in 1993 were used to explore predictors of asthma, by means of relative risks and the results of logistic regression analysis. The cumulative incidence of asthma (3.9%) appeared to relate to using coal for cooking/heating (RR = 2.78) and parental smoking (RR = 1.21), in addition to known effects of parental asthma (RR = 5.54), history of atopic eczema (RR = 4.66) or allergic conjunctivitis (RR = 4.11). Although the cumulative incidence of asthma increased from 2.0% in non-smoking families to 4.2% in one-parent-smoking families and 5.4% in two-parent-smoking families the results of multivariate analysis confirmed only the effects of parental asthma (logOR = 4.59), atopy (logOR = 3.88) and using coal for cooking (logOR = 3.33). The effect of exposure to parental smoking was not statistically significant (logOR = 2.33). The findings, in addition to well known host-related factors, suggest the role of environmental exposures (indoor air quality) in childhood asthma and support a challenging hypothesis concerning protective effect of measles infection--the study revealed no incidence of asthma in a group of 38 children who acquired measles before the follow-up started.

[Predictors of persistence of remission of the respiratory symptoms in school children]. / Czynniki prognostyczne utrzymywania sie i remisji objawów ze strony ukladu oddechowego u dzieci.

The evolution of the respiratory symptoms in school children hampers the interpretation of epidemiologic findings concerning potential risk factors. It is thus important to identify prognostic factors that predict symptoms' persistence or remission. A seven-year follow-up of 663 children showed that half of them experience the remission of cough, chest wheeze and attacks of dyspnea. The results of multivariate analysis showed that the persistence of cough is more likely to occur in children with a history of spastic bronchitis (logOR = 3.1; 95% CI: 1.3-7.1) and the presence of coal-stove in kitchen (logOR = 3.1: 95% CI: 1.4-6.9). The probability of persistence of wheeze depends on history of bronchitis (logOR = 3.9; 95% CI: 1.4-11.4), history of parental asthma(logOR = 4.8; 95% CI: 1.1-25.2) and diagnosis of pollen sensitivity (logOR = 3.9; 95% CI = 1.2-12.9). On the other hand the persistence of attack of dyspnea was associated with a shortness of breath on exertion(logOR = 4.7; 95% CI: 1.5-16.8). The results of the study confirm an important role of medical history in the assessment of prognosis of the respiratory health status in children.

Results of the health survey of a population living in a vicinity of a large waste site (Warsaw, Poland).

Although attracting rapidly increasing attention from the public, the health impact of environmental exposures related to the operation of waste dumping sites is a relatively new issue in Poland. However, the problem cannot be neglected in light of the fact that environmental impact assessment in selected sites revealed the lack of sufficient documentation concerning quantity and quality of dumped materials and poor technological management of the sites. The paper describes the results of health survey performed in a vicinity of a country's largest municipal waste site. Although the study came across methodological obstacles involving low participation and difficult to estimate representativeness of the examined group its findings obtained in 393 adults and 188 children and the results of internal comparisons revealed some interesting observations. Three "exposure-classification" variables were used in data analysis (geographical location, distance, "waste traffic" intensity) and health status was examined by means of self- and physician-administered questionnaire, physical examination and routine laboratory analyses. Relationship, although weak, of subjective symptoms and objective findings with the place of residence vis-a-vis the waste site location suggests that potential health effects of waste site-related environmental exposures might include psychological problems, digestive tract disorders and respiratory disorders as well as allergic symptoms. An intriguing observation concerning pregnancy-related health outcomes was made. The exact role of environmental determinants in this respect remains unclear and should be addressed by specific environmental epidemiological and toxicological studies. The findings as well as subjects' concern about health consequences of exposures to waste-related pollution (paralleled by subjective perception of impaired health) justify further investigations and public health initiatives including environmental impact assessment and health monitoring activities targeting populations living in a vicinity of waste sites in Poland.

Air pollution and acute respiratory diseases in children: regression analysis of morbidity data.

The aim of this study was to investigate the relationship between acute respiratory diseases and the air quality in the urban area of the Upper Silesian Industrial Zone during autumn and winter with special emphasis on temporal variability in the air concentrations of pollutants. The survey was carried out in 5 primary care units in Chorzów where the morbidity data on the selected respiratory diseases were collected from 1 November 1992 to 31 March 1993. The air pollution data were obtained from the monitoring station, being a part of the Sanitary and Epidemiological Station Network. Regression analysis with mean values of concentrations of air pollutants as explanatory variables revealed a positive effect of combined suspended particulate matter and SO2 concentration on the increased prevalence of bronchitis and bronchiolitis. Similar and even stronger effect was observed at the level of temporal variability coefficients of the air pollutants. A hypothesis that temporal variability of the air concentration of pollutants might be a more relevant factor for determining the prevalence of respiratory diseases than simple mean values of the pollutant concentrations is very interesting worthy of further investigations.

[Low back pain syndrome in coal miners: preliminary results of an epidemiological study]. / Bóle krzyza u górników kopaln wegla kamiennego--wstepne wyniki badan.

The objective of the study was to determine the occurrence of low-back-pain syndrome in coal-miners and to compare the results obtained in the study and control groups. In two groups of subjects (624 employees of the 'Staszic' and 598 employees of the 'Sosnica' mines) the survey and medical assessment were performed and available medical records reviewed. Two groups were similar in terms of age and employment duration, however, working conditions in the 'Sosnica' mine were more difficult, and associated with a larger physical burden. All workers were divided into three groups according to the workload: workers with 'heavy workload' (35.9%), 'medium workload' (37.6%), and 'light workload'. The control group consisted of 449 policemen matched by age and the number of years preceding their retirement. The study revealed that low-back-pain syndrome occurred in 66.4% and 62.2% of the 'Sosnica' and 'Staszic' miners, respectively, while in policemen this figure accounted for only 7.5%. Among miners and policemen, a group with the employment ranging from 10 to 20 years was identified. The group comprised 730 miners, including 179 persons with light workload, and 142 policemen. Law-back-pain occurred in 61.6% of miners and in 14.1% of policemen. In miners the syndrome was associated mainly with lifting heavy objects or with an inappropriate forced position of the body at work. The preliminary results of the epidemiological study indicated that low-back-pain syndrome occurred more frequently in coal-miners than in policemen.

Environmental pollution and child health in central and Eastern Europe.

For the last 50 years, the economic and industrial development of the nations of Central and Eastern Europe has been achieved at the cost of environmental degradation. The health risks posed by this pollution to children and the steps necessary to ameliorate such risks are only beginning to be investigated. At a recent conference in Poland, sponsored in part by the National Institute of Environmental Health Sciences, participants from 11 countries in the region, together with scientists from Western Europe and the United States, met to share information regarding pediatric environmental health in Central and Eastern Europe, to consider methodologic issues in the design and conduct of such studies, and to discuss preventive strategies. This report summarizes the deliberations, outlines problem areas such as heavy metals and air pollution, delineates research and training needs to help Central and Eastern Europeans deal more effectively with such problems, and recommends specific future actions and collaborative efforts.

Exposure to lead and other metals in children from Katowice district, Poland.

OBJECTIVES: To assess the exposure to toxic metals and to evaluate its possible association with essential elements and socioeconomic status in children from the town of Bytom in the Katowice area; this area is one of the most polluted industrialized regions in Poland. METHODS: Concentrations of lead, cadmium, mercury, selenium, magnesium, copper, and zinc were determined in whole blood of 211 children aged 9 years. The samples were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). Information on socioeconomic factors was collected using questionnaires. Concentrations of trace elements in the blood of 24 Swedish children aged 9-10 years were used for comparisons. RESULTS: The concentrations of lead detected in the blood of the Polish children ranged from 0.09 to 1.9 mumol/l, with the median value being 0.27 mumol/l. Statistically significant associations were found between lead and such socioeconomic factors as the number of siblings, trips outside the region, maternal smoking, playing outdoors, and apartment standard. The average blood lead level was about 3 times higher in the Polish children than in the Swedish group. The median blood concentration of cadmium found in the Polish children was 3.4 nmol/l (range 1.1-41 nmol/l; almost 3 times higher than that detected in the Swedish children), and that of mercury was 3 nmol/l (range 0.5-11 nmol/l). The median blood levels and ranges of the essential elements were 1.1 (0.7-2.0) mumol/l for selenium, 1.5 (1.2-1.9) mmol/l for magnesium, 17 (13-22) mumol/l for copper, and 78 (54-104) mumol/l for zinc, respectively. The concentrations of selenium and magnesium were significantly lower in the Polish group as compared with the Swedish children. CONCLUSIONS: In all, 7% of the Polish children had blood lead levels exceeding 0.5 mumol/l, the concentration above which negative effects on mental development have been reported. However, the findings indicate a decrease in lead exposure during recent years among the Bytom children.

[Assessment of answer repeatability in a questionnaire evaluation of respiratory tract symptoms in children]. / Ocena powtarzalnosci odpowiedzi w kwestionariuszowym badaniu objawów ze strony ukladu oddechowego u dzieci.

Repeatability of parental answers to questions concerning respiratory symptoms and environmental exposure was examined in 250 children. Repeatability of answers, given two times with a 6 week interval, in 250 questionnaires was assessed with two methods: by accounting the percentage of the same answers and with the use of the Kappa test. It was demonstrated that answers concerning respiratory tract symptoms were characterized by the agreement rate of 77-99% and the Kappa values ranging from 0.44 to 0.76. The answers to questions concerning environmental factors were more satisfactory, with the agreement rate: 89-95% and the Kappa values: 0.68-0.93. The above results correspond to the literature data on repeatability of results of the standard questionnaire investigation; this testifies to credibility of the questionnaire investigation of the prevalence and risk factors in respiratory disorders in children.

Blood lead levels in urban children of Katowice Voivodship, Poland: results of the population-based biomonitoring and surveillance program.

The paper presents the results of the large-scale blood lead levels survey in pre-school urban children living in industrial area of Poland (Katowice Voivodship, Upper Silesian Industrial Zone-USIZ). The program, established in 1993, involves education, screening and medical care of case-children, as its major elements. Until December 1995 six thousand nine hundred sixty nine children aged 2-6 years have been examined in three towns (Chorzów, Kalowice, Sosnowiec). Geometric mean value of blood lead level (PbB) was slightly but not statistically significantly larger in boys (6.68 +/- 1.51 micrograms/dl) than in girls (6.58 +/- 1.54 micrograms/dl). In a multiple regression analysis the following variables explained variation in PbB: town (p = 0.0001), age (p = 0.005), floor on which apartment was located (p = 0.0001), number of siblings (p = 0.0001), apartment quality (p = 0.0001), carpet in a child's room (p = 0.0001), consumption of locally grown vegetables (p = 0.007), frequent trips outside the region (p = 0.0001). The results were verified with PbB as dichotomous variable. The occurrence of PbB above 10 micrograms/dl (frequency, 14.2%-17.2%) was associated with floor on which apartment was located, number of siblings, apartment's quality, the presence of carpet in child's room and frequent trips outside the region. The occurrence of PbB above 15 micrograms/dl (frequency: 2.5%-4.2% of children) was associated with the same variables and additionally, with the place of residence and intensity of vehicle traffic. The findings yield reliable population-based estimates of the risk of over-exposure of "non-hot-spot" urban children to environmental lead and highlight the important role of factors that could be classified as environmental and socio-economical determinants of blood lead level. Among environmental factors deposits of lead are still a problem in a densely populated industrial center of USIZ and the use of leaded gasoline adds to the magnitude of exposure.

[Evaluation of the effect of environmental exposure to tobacco smoke on variability of peak expiratory flow rate in children]. / Ocena wplywu srodowiskowego narazenia na dym tytoniowy na zmiennosc w zakresie szczytowego przeplywu wydechowego u dzieci.

A panel study was conducted in autumn (116 children) and repeated in spring (66 children) to test the hypothesis that the individual variability of peak expiratory flow rate (PEFR) depends on the environmental exposure to tobacco smoke (ETS). PEFR was measured twice a day (morning: PEFR-M; evening: PEFR-E), using individual meters at homes, in children exposed (ETS+) and not exposed (ETS-) to tobacco smoke at home. In examined groups the individual variability of PEFR-M was--on average--8.0% (ETS+; autumn), 8.1% (ETS+; spring), 10.5% (ETS-; autumn) and 7.7% (ETS-; spring). The individual variability of PEFR-E was 8.0% (ETS+; autumn), 7.9% (ETS+; spring), 9.5% (ETS-; autumn) and 7.4% (ETS-; spring). The results of multivariate analysis of within- and between-subject variability showed the presence of statistically significant within-subject variability only in ETS+ group (PEFR-M in autumn; PEFR-M and PEFR-E in spring). With all the limitations of a panel study design the findings suggest that environmental exposure to tobacco smoke in children affects the degree of within-subject variability of PEFR in children.

Lung function in children of upper Silesian industrial zone, Poland: results of the cross-sectional study in two towns of different ambient air pollution levels.

In two groups of children aged 7-9 years residing in two towns in the most industrial region of Poland, Chorzów (C - "higher air pollution") and Mikolów (M - "lower air pollution"), lung function testing was performed in a cross-sectional manner in order to examine if the spirometric indices in children depended on the ambient air pollution level as assessed by area measurements. The between-town difference in ambient air quality was statistically significant with respect to particulate and gaseous pollutants (SO2 and NO2). In Chorzów 855 and in Mikolów 356 children were studied. Both groups (C and M) were similar in terms of sex, age, height and weight. In boys, the group mean values of lung function indices (in% of predicted values) were for FVC: c-98.1, M-98.0; FEV1: C-109.5, M-107.8; PEF; C-84.3, M-80.0 (p < 0.05); MEF50: C-105.5, M-100.4 (p < 0.05); MEF25: C-100.5, M-93.7 (p < 0.05). In girls, the respective values were for FVC: C-100.4, M-100.3; FEV1: C-107.6 M-107.1; PEF: C-78.4, M-77.6; MEF50: C-103.5, M-104.2; MEF25: C-97.6 M-99.9. Stratification for the presence of respiratory symptoms or exposure to environmental tobacco smoke did not change the between-town differences in boys' lung function. The findings were confirmed by the results of multivariate analyses. The study did not provide evidence that children living in Chorzów had poorer lung function compared with children living in Mikolów. The results highlight problems regarding a cross-sectional approach to the investigation into the effect of ambient air pollution of lung function, such as the study design, the validity of exposure assessment by means of stationary monitoring, the subjects' age and sensitivity of the evaluation of lung function.

Respiratory symptoms in children of Upper Silesia, Poland cross-sectional study in two towns of different air pollution levels.

In children aged 7-9 years residing in the town of Chorzow (C) and in the town of Mikolow (M), located 30 km apart (Upper Silesia, the industrial part of Poland), respiratory symptoms were ascertained according to the parental answers to WHO-Questionnaire. Mean annual concentrations of air pollutants are higher in Chorzow than in Mikolow, and recent mean values of 24 hr measurements over November 1992-January 1993 confirmed the between-town gradient (p < 0.001) for particulates (C:166 micrograms/m3); M:129 micrograms/m3), SO2 (C:153 micrograms/m3); M:92 micrograms/m3) and NO2 (C:69 micrograms/m3); M:26 micrograms/m3). In Chorzow 24.8% (n = 1,142) and in Mikolow 25.6% (n = 480) of all eligible children aged 7-9 years were examined. Both groups (C and M) were similar in terms of sex, family history of asthma and cough lasting for 3 months (C:31.6%; M:32.3%). Frequency of the following respiratory symptoms statistically significantly (p < 0.05) differed between two groups: chest wheezing (C:21.4%; M:17.1%) and attacks of asthmatic dyspnea (C:10.3%; M:6.2%). Also, the diagnosis of asthma by physician was more prevalent in Chorzow (C:3.5%; M:1.3%; p < 0.05). Logistic regression analysis showed that after controlling for family history of asthma, environmental tobacco smoke and housing condition, the place of residence (C versus M) was statistically significantly associated with attacks of asthmatic dyspnea (p < 0.05) and a "borderline' significance of this factor was found in relation to wheezing (p = 0.06) and physician-diagnosed asthma (p = 0.07). The survey provided the estimate of the prevalence of chronic respiratory symptoms in children living in the most polluted urban area of Poland. Although the design of the study precludes more specific etiologic conclusions on environmental exposures the apparently higher prevalence of symptoms in children living in a more polluted town deserves further investigation.

Occupational exposure to dusts containing asbestos and chronic airways disease.

Chronic inhalation of asbestos fibres has been recognized as a cause of both malignant and non-malignant diseases of lung parenchyma and pleura. The objective of this review was to examine epidemiological evidence concerning this type of occupational exposure as a risk factor for chronic disorders of airways, classified as peripheral airways disease and chronic airflow limitation. A number of published pathophysiological findings that are suggestive of the involvement of peripheral airways in workers exposed to asbestos could be supported by workforce-based assessment of simple tests of small airways function. In asbestos workers the tests' results are usually found to be lower than in reference groups and depend on cumulative exposure. The cross-sectional surveys carried out in large populations of workers exposed to asbestos document an association of both forced expiratory volume in the first second and forced vital capacity with increasing exposure. The majority of the studies reviewed show an exposure-response type of association, also documented by longitudinal studies. The presence of lung function impairment in subjects with normal chest radiographs is compatible with the view that the airway defect may be an independent outcome of exposure to asbestos. The occurrence of the obstructive ventilatory impairment is not infrequent in workforce-based cross-sectional studies, also in nonsmokers in whom the prevalence of obstruction was found to exceed the prevalence of restriction. In conclusion, the review provides evidence that peripheral airways abnormality could be a consequence of inhalation of asbestos. This association seems to be strong and exposure to mineral dust containing asbestos can be therefore regarded as one of the etiologic factors in the genesis of peripheral airways abnormalities. A number of findings favour the plausibility of causal association of chronic airflow limitation with exposure to asbestos dust. However, the insufficient epidemiological data concerning the relationships of an obstructive pattern of ventilatory defect preclude the elaboration of frequent occurrence of obstructive profile in non-smoking asbestos workers. The epidemiologic evidence on association between occupational exposure to dusts containing asbestos and chronic airways disease confirms the presence of "mineral dust airways disease" and adds credibility to the concept of "work-related chronic airflow limitation".

[Back pain in coal miners of anthracite coal--pilot study results]. / Bóle krzyza u górników kopaln wegla kamiennego--wyniki badania pilotowego.

The objective of the study was to determine the occurrence of a low-back-pain syndrome in coalminers. The pilot study also aimed at the evaluation of the study design and methods, prior to planned full-scale epidemiological assessment of the syndrome in this workforce. In two groups of subjects (204 persons employed in the "Staszic" mine and 200 in the "Sosnica" mine) a questionnaire survey and medical assessment were carried out, and available medical records were reviewed. Two groups were similar in terms of age and duration of work, but workers of the "Sosnica" mine have worked in more difficult conditions, associated with a larger physical burden. The overall frequency of a low-back-pain syndrome was 73.2% in the "Sosnica" miners and 65.2% in the other group. The syndrome occurrence seemed to depend on the age and occupational history. However, conclusions regarding work-relatedness of the symptoms are not warranted in the light of the pilot study results. The study yielded background data which will contribute to the improvement of the study protocol, being prepared for the major epidemiological assessment of a low-back-pain syndrome in coalminers.

[Bronchial asthma and chronic respiratory symptoms in the population of children in the Katowice voivodship--prevalence and risk factors]. / Astma oskrzelowa i objawy ze strony ukladu oddechowego w populacji dzieci w województwie katowickim--czestosc wystepowania i podstawowe czynniki ryzyka.

Respiratory questionnaire survey in first grade students attending all public primary school in the city of Sosnowiec included 79.5% of all eligible children. In 1233 girls (G) and 1293 boys (B) the cumulative prevalence of chronic cough was: G - 17.5%, B - 20.8%, chest wheezing: G - 17.4%, B - 22.3%, and of attacks of dyspnea: G - 6.4%, B - 10.7%. Physician diagnosed asthma was found in 2.1% of girls and 3.4% of boys. The results of the logistic regression analysis showed statistically significant effects of sex and family history of asthma on all respiratory symptoms and diagnosis of asthma. Symptoms of chest wheezing depended also on environmental tobacco smoke and apartment density score (person/room). In relation to chronic cough the following additional risk factors were identified: place of birth in the Voivodship, hospitalization in the first month of life and breast feeding. A relatively low cumulative prevalence of childhood asthma in Sosnowiec, in comparison with the prevalence of epidemiological signs of asthmatic tendency, suggest that the magnitude of the problem of childhood asthma could be underestimated, if assessed only on physician diagnosed cases. The findings provide background information for further research on respiratory health in children living in the region of substantial ambient air pollution.

Blood lead concentrations in school children of Upper Silesian Industrial Zone, Poland.

Upper Silesian Industrial Zone (Katowice Voivodship, Poland), the country most industrialized and densely populated region is well recognized for the magnitude of environmental problems. Due to local lead mining and processing environmental exposure to lead is considered one of the most important hazards to the health of children. In the past, clinically confirmed cases of lead intoxication in children have been found and recent blood lead monitoring in major point source impact areas have documented increased blood lead concentration in children. However, much less is known about blood lead concentrations in general population of children who are exposed to increased levels of lead in ambient and soil. The study was undertaken in order to estimate the mean blood lead concentration (PbB) and its range in children aged seven years residing in urban non-point source impact area of Katowice Voivodship, and to examine potential determinants of increased blood lead concentration in these children. In a systematic sample of 431 children aged 7 years (208 girls and 223 boys), living in two large cities in the centre of Upper Silesian Industrial Zone the geometric mean and standard deviation of PbB was 7.94 +/- 1.48 micrograms/dl (range 4.0-38.0 micrograms/dl) and did not depend on sex or the city of residence. PbB equal to or larger than 15 micrograms/dl was found in 8.1% of children and PbB equal to or larger than 10 micrograms/dl in 27.4% of children. Blood lead concentration was associated with a number of factors that could be classified as family factors, housing and environmental factors. The identified risk factors add credibility to suggested directions of preventive measures that should extend beyond already implemented lead emission control in the industry and involve increased use of unleaded gasoline, upgrading of housing conditions and promotion of proper hygienic standards on a household level. The findings of the study indicate that children living in urban area of Upper Silesian Industrial Zone are at risk of overexposure to lead in environment, and justify the implementation of population-based screening program targeting children in younger age groups in the region.