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B Wojtyniak

Publications and source records attributed to B Wojtyniak.

At least 19 recordsLinked to original sources
PubMed2006

Short-term effects of nitrogen dioxide on mortality: an analysis within the APHEA project.

The short-term effects of nitrogen dioxide (NO(2)) on total, cardiovascular and respiratory mortality in 30 European cities participating in the Air Pollution on Health: a European Approach (APHEA)-2 project were investigated. The association was examined using hierarchical models implemented in two stages. In the first stage, data from each city were analysed separately, whereas in the second stage, the city-specific air pollution estimates were regressed on city-specific covariates to obtain overall estimates and to explore sources of possible heterogeneity. A significant association of NO(2) with total, cardiovascular and respiratory mortality was found, with stronger effects on cause-specific mortality. There was evidence of confounding in respiratory mortality with black smoke and sulphur dioxide. The effect of NO(2) on total and cardiovascular mortality was observed mainly in western and southern European cities, and was larger when smoking prevalence was lower and household gas consumption was higher. The effect of NO(2) on respiratory mortality was higher in cities with a larger proportion of elderly persons in the population and higher levels of particulate matter with a 50% cut-off aerodynamic diameter of 10 mum. The results of this large study are consistent with an independent effect of nitrogen dioxide on mortality, but the role of nitrogen dioxide as a surrogate of other unmeasured pollutants cannot be completely ruled out.

Air Pollutants↗
PubMed2003

Short-term effects of ambient particles on mortality in the elderly: results from 28 cities in the APHEA2 project.

Within the framework of the APHEA2 (Air Pollution on Health: a European Approach) project, the effects of ambient particles on mortality among persons > or = 65 yrs were investigated. Daily measurements for particles with a 50% cut-off aerodynamic diameter of 10 microm (PM10) and black smoke (BS), as well as the daily number of deaths among persons > or = 65 yrs of age, from 29 European cities, have been collected. Data on other pollutants and meteorological variables, to adjust for confounding effects and data on city characteristics, to investigate potential effect modification, were also recorded. For individual city analysis, generalised additive models extending Poisson regression, using a locally weighted regression (LOESS) smoother to control for seasonal effects, were applied. To combine individual city results and explore effect modification, second stage regression models were applied. The per cent increase (95% confidence intervals), associated with a 10 microg x m(-3) increase in PM10, in the elderly daily number of deaths was 0.8%, (0.7-0.9%) and the corresponding number for BS was 0.6%, (0.5-0.8%). The effect size was modified by the long-term average levels of nitrogen dioxide (higher levels were associated with larger effects), temperature (larger effects were observed in warmer countries), and by the proportion of the elderly in each city (a larger proportion was associated with higher effects). These results indicate that ambient particles have effects on mortality among the elderly, with relative risks comparable or slightly higher than those observed for total mortality and similar effect modification patterns. The effects among the older persons are of particular importance, since the attributable number of events will be much larger, compared to the number of deaths among the younger population.

Aged↗
PubMed2001

Outdoor sulphur dioxide and respiratory symptoms in Czech and Polish school children: a small-area study (SAVIAH). Small-Area Variation in Air Pollution and Health.

OBJECTIVES: Air pollution has been linked to respiratory outcomes but controversy persists about its long-term effects. We used a novel technique to estimate the outdoor concentrations of sulphur dioxide (SO2) at small-area level to study the long-term effects on respiratory symptoms and disease in children. METHODS: As part of the international SAVIAH study, parents of 8,013 children aged 7-10 studied in Prague (Czech Republic) and Poznan (Poland) completed a questionnaire covering respiratory health, demographic and socio-economic factors and health behaviours (response rate 91%). This report is based on 6,959 children with complete data. Outdoor SO2 was measured by passive samplers at 80 sites in Poznan and 50 sites in Prague during 2-week campaigns. Concentrations of SO2 at each point (location) in the study areas were estimated from these data by modelling in a geographical information system. The mean of the estimated SO2 concentrations at children's homes and schools was used as an indicator of exposure to outdoor SO2. RESULTS: The prevalence of respiratory outcomes was similar in both cities. In the pooled data, 12% of children had experienced wheezing/whistling in the past 12 months; 28% had a lifetime prevalence of wheezing/whistling; 14% had a dry cough at night; and 3% had had asthma diagnosed by a doctor. The estimated mean exposure to outdoor SO2 was 80 (range 44-140) microg/m3 in Poznan and 84 (66-97) microg/m3 in Prague. After socio-economic characteristics and other covariates were controlled for, SO2 was associated with wheezing/whistling in the past 12 months (adjusted OR per 50 microg/m3 1.32, 95% CI 1.10-1.57), lifetime prevalence of wheezing/whistling (OR 1.13, 95% CI 0.99-1.30), and lifetime prevalence of asthma diagnosed by a doctor (OR 1.39, 95% CI 1.01-1.92). The association with dry cough at night did not reach statistical significance. CONCLUSIONS: In these two Central European cities with relatively high levels of air pollution, small-area based indicators of long-term outdoor winter concentrations of SO2 were associated with wheezing/whistling and with asthma diagnosed by a doctor.

Air Pollutants↗
PubMed2001

Confounding and effect modification in the short-term effects of ambient particles on total mortality: results from 29 European cities within the APHEA2 project.

We present the results of the Air Pollution and Health: A European Approach 2 (APHEA2) project on short-term effects of ambient particles on mortality with emphasis on effect modification. We used daily measurements for particulate matter less than 10 microm in aerodynamic diameter (PM10) and/or black smoke from 29 European cities. We considered confounding from other pollutants as well as meteorologic and chronologic variables. We investigated several variables describing the cities' pollution, climate, population, and geography as potential effect modifiers. For the individual city analysis, generalized additive models extending Poisson regression, using a smoother to control for seasonal patterns, were applied. To provide quantitative summaries of the results and explain remaining heterogeneity, we applied second-stage regression models. The estimated increase in the daily number of deaths for all ages for a 10 microg/m3 increase in daily PM10 or black smoke concentrations was 0.6% [95% confidence interval (CI) = 0.4-0.8%], whereas for the elderly it was slightly higher. We found important effect modification for several of the variables studied. Thus, in a city with low average NO2, the estimated increase in daily mortality for an increase of 10 microg/m3 in PM10 was 0.19 (95% CI = 0.00-0.41), whereas in a city with high average NO2 it was 0.80% (95% CI = 0.67-0.93%); in a relatively cold climate the corresponding effect was 0.29% (95% CI = 0.16-0.42), whereas in a warm climate it was 0.82% (95% CI = 0.69-0.96); in a city with low standardized mortality rate it was 0.80% (95% CI = 0.65-0.95%), and in one with a high rate it was 0.43% (95% CI = 0.24-0.62). Our results confirm those previously reported on the effects of ambient particles on mortality. Furthermore, they show that the heterogeneity found in the effect parameters among cities reflects real effect modification, which is explained by specific city characteristics.

Aged↗
PubMed2001

Investigating regional differences in short-term effects of air pollution on daily mortality in the APHEA project: a sensitivity analysis for controlling long-term trends and seasonality.

Short-term effects of air pollution on daily mortality in eight western and five central-eastern European countries have been reported previously, as part of the APHEA project. One intriguing finding was that the effects were lower in central-eastern European cities. The analysis used sinusoidal terms for seasonal control and polynomial terms for meteorologic variables, but this is a more rigid approach than the currently accepted method, which uses generalized additive models (GAM). We therefore reanalyzed the original data to examine the sensitivity of the results to the statistical model. The data were identical to those used in the earlier analyses. The outcome was the daily total number of deaths, and the pollutants analyzed were black smoke (BS) and sulfur dioxide (SO(2)). The analyses were restricted to days with pollutant concentration < 200 microg/m(3) and < 150 microg/m(3) alternately. We used Poisson regression in a GAM model, and combined individual city regression coefficients using fixed and random-effect models. An increase in BS by 50 microg/m(3) was associated with a 2.2% and 3.1% increase in mortality when analysis was restricted to days < 200 microg/m(3) and < 150 microg/m(3), respectively. The corresponding figures were 5.0% and 5.6% for a similar increase in SO(2). These estimates are larger than the ones published previously: by 69% for BS and 55% for SO(2). The increase occurred only in central-eastern European cities. The ratio of western to central-eastern cities for estimates was reduced to 1.3 for BS (previously 4.8) and 2.6 for SO(2) (previously 4.4). We conclude that part of the heterogeneity in the estimates of air pollution effects between western and central-eastern cities reported in previous publications was caused by the statistical approach used and the inclusion of days with pollutant levels above 150 microg/m(3). However, these results must be investigated further.

Adolescent↗
PubMed2001

The future of chronic diseases.

Major chronic diseases continue to be the main health scourge of the most developed countries, have only recently been retreating in frequency in the fledgling market economies, and are becoming dominant in many populous areas of the developing world. The descriptive evidence from the developments of the near past strongly suggests that much of the control outcomes have already been achieved with the existent imperfect causative knowledge. The continuation of desirable trends in major chronic diseases in some places like Central & Eastern Europe, is uncertain within the intermediate time range without gaining more etiological clues, among which the role of medical care is worthy of reconsideration. Other factors can grow in importance, like obesity, which may be freed from the suppressive influence of cigarette smoking to trigger major mass pathologies, like type 2 diabetes mellitus, arterial hypertension, some cancers etc. The role of social underpriviledge seems recalcitrant, although the part played by social share of biological risk agents may diminish in response to educational persuasion. The remotest destinies of some chronic diseases may depend on the mixture of external and genetic influences ending as predispositions towards some ailments, antecedents of which might have protected their carriers from dangers of the past unfriendly environment, like obesity (or diabetes) against famine, or hypertension against inefficient defense reaction. The resulting medium-range prediction of well-being for inhabitants of more developed world may not be forbidding, since increasing life expectancy needs not be synonymous with disability, and attaining old age does not require excessive sacrifice, beyond reducing number smoked, or preserving decent respiratory volumes.

Chronic Disease↗
PubMed2000

Use of health information systems in the Russian federation in the assessment of environmental health effects.

The Russian Federation has made an intensive effort to compile and use information on the environment and human health. In 1996-1997, we evaluated the information that was collected and analyzed on the local (raion), regional (oblast), and federal levels with reference to its usefulness in the assessment of environmental health effects. The Russian Federation maintains standardized nationwide institutions that routinely collect health data in polyclinics and hospitals and then report to the national offices. The allocations of the workforce and the broad range of surveyed health outcomes are extensive, but a lack of systematic control of information quality limits the ability to take full advantage of these efforts. On the other hand, the hierarchical system of data collection has advantages over more decentralized or commercial health systems. A major weakness in the current reporting is the aggregation and transformation of data. Although this may not disturb the generation of health statistics, it seriously limits the use of regional and federal level data in the assessment of health effects of environmental exposures. In spite of limitations, some revised approaches to the analysis of existing data may be both feasible and fruitful. Combining information from routine data and newly collected data is likely to be the most effective way to assess the relationship between environmental exposures and diseases. Although there is a strong and justifiable desire to rapidly translate information of environmental health effects into policy alternatives, at present, it seems more useful to emphasize data quality, completeness, and plans for the use of data.

Data Collection↗
PubMed1999

Recommendations for the monitoring of short-term health effects of air pollution: lessons from the APHEA Multi Centre European Study.

Accumulating evidence from European cities indicates that current levels of ambient air pollution are likely to be associated with detectable effects on daily mortality and hospital admissions. Public health authorities everywhere are concerned about the possible effects of air pollution on the health of their populations but there are no guidelines for how these effects can efficiently be monitored. Furthermore, decisions about air pollution monitoring tend to be made without reference to the epidemiological requirements of health monitoring. The APHEA project (Air Pollution and Health a European Approach) investigated the short-term health effects of air pollution in 15 European cities. Experience gained in this project provides a basis for recommendations to public health and environmental authorities concerning the requirements for a basic health monitoring system. This paper considers the theoretical and practical aspects of a monitoring system and makes recommendations concerning 1) the minimum data set required, 2) the methods of statistical analysis and presentation and 3) Europe-wide coordination of monitoring.

Air Pollution↗
PubMed1998

Duration of protective immunity conferred by maternal tetanus toxoid immunization: further evidence from Matlab, Bangladesh.

OBJECTIVES: Although maternal tetanus immunization has been shown to be highly effective in the prevention of neonatal tetanus, unresolved questions remain concerning the required minimum number of doses and the resulting duration of effective immunity. This study examined the duration of effective immunity against neonatal tetanus provided by maternal tetanus immunization. METHODS: A randomized, double-blind cholera vaccine trial of 41,571 children and nonpregnant adult women carried out in 1974 in the Matlab comparison area of rural Bangladesh provided a unique opportunity to address dose and immunity issues. RESULTS: Children of women who received either 1 or 2 injections of tetanus toxoid experienced 4- to 14-day mortality levels consistently lower than those of children of unimmunized mothers. Analysis of neonatal-tetanus-related mortality showed that 2 injections of tetanus toxoid provided significant protection for subsequent durations of up to 12 or 13 years. CONCLUSIONS: The data demonstrate that a limited-dose regimen of maternal tetanus toxoid provides significant and extended protection against the risk of neonatal tetanus death.

Adolescent↗
PubMed1998

Time-series analysis of air pollution and cause-specific mortality.

Ten large European cities provided data on daily air pollution as well as mortality from respiratory and cardiovascular mortality. We used Poisson autoregressive models that controlled for trend, season, influenza epidemics, and meteorologic influences to assess the short-term effects of air pollution at each city. We then compared and pooled the city-specific results in a meta-analysis. The pooled relative risks of daily deaths from cardiovascular conditions were 1.02 [95% confidence interval (CI) = 1.01-1.04] for a 50 microg/m3 increment in the concentration of black smoke and 1.04 (95% CI = 1.01-1.06) for an increase in sulfur dioxide levels in western European cities. For respiratory diseases, these figures were 1.04 (95% CI = 1.02-1.07) and 1.05 (95% CI = 1.03-1.07), respectively. These associations were not found in the five central European cities. Eight-hour averages of ozone were also moderately associated with daily mortality in western European cities (relative risk = 1.02; 95% CI = 1.00-1.03 for cardiovascular conditions and relative risk = 1.06; 95% CI = 1.02-1.10 for respiratory conditions). Nitrogen dioxide did not show consistent relations with daily mortality. These results are similar to previously published data and add credence to the causal interpretation of these associations at levels of air pollution close to or lower than current European standards.

Aged↗
PubMed1998

[SO2 and NO2 air pollution measurement by passive monitors].

Air pollution concentration measurement in Poland are routinely carried on using aspiration methods. This technique required suitable measurement point preparation and its monitoring. During last years passive monitors are used more and more frequently for some air pollutants concentrations measurement. The above mentioned method is recommended when spatial differentiation of air pollution are analized. Results of such measurements carried of in the area of Poznań are presented in this contribution.

Air↗
PubMed1997

Short-term effects of ambient sulphur dioxide and particulate matter on mortality in 12 European cities: results from time series data from the APHEA project. Air Pollution and Health: a European Approach.

OBJECTIVES: To carry out a prospective combined quantitative analysis of the associations between all cause mortality and ambient particulate matter and sulphur dioxide. DESIGN: Analysis of time series data on daily number of deaths from all causes and concentrations of sulphur dioxide and particulate matter (measured as black smoke or particles smaller than 10 microns in diameter (PM10)) and potential confounders. SETTING: 12 European cities in the APHEA project (Air Pollution and Health: a European Approach). MAIN OUTCOME MEASURE: Relative risk of death. RESULTS: In western European cities it was found that an increase of 50 micrograms/m3 in sulphur dioxide or black smoke was associated with a 3% (95% confidence interval 2% to 4%) increase in daily mortality and the corresponding figure for PM10 was 2% (1% to 3%). In central eastern European cities the increase in mortality associated with a 50 micrograms/m3 change in sulphur dioxide was 0.8% (-0.1% to 2.4%) and in black smoke 0.6% (0.1% to 1.1%). Cumulative effects of prolonged (two to four days) exposure to air pollutants resulted in estimates comparable with the one day effects. The effects of both pollutants were stronger during the summer and were mutually independent. CONCLUSIONS: The internal consistency of the results in western European cities with wide differences in climate and environmental conditions suggest that these associations may be causal. The long term health impact of these effects is uncertain, but today's relatively low levels of sulphur dioxide and particles still have detectable short term effects on health and further reductions in air pollution are advisable.

Air Pollutants↗
PubMed1997

Urban air pollution and emergency admissions for asthma in four European cities: the APHEA Project.

BACKGROUND: A study was undertaken to assess the combined association between urban air pollution and emergency admissions for asthma during the years 1986-92 in Barcelona, Helsinki, Paris and London. METHODS: Daily counts were made of asthma admissions and visits to the emergency room in adults (age range 15-64 years) and children (< 15 years). Covariates were short term fluctuations in temperature and humidity, viral epidemics, day of the week effects, and seasonal and secular trends. Estimates from all the cities were obtained for the entire period and separately by warm or cold seasons using Poisson time-series regression models. Combined associations were estimated using meta-analysis techniques. RESULTS: Daily admissions for asthma in adults increased significantly with increasing ambient levels of nitrogen dioxide (NO2) (relative risk (RR) per 50 micrograms/m3 increase 1.029, 95% CI 1.003 to 1.055) and non-significantly with particles measured as black smoke (RR 1.021, 95% CI 0.985 to 1.059). The association between asthma admissions and ozone (O3) was heterogeneous among cities. In children, daily admissions increased significantly with sulphur dioxide (SO2) (RR 1.075, 95% CI 1.026 to 1.126) and non-significantly with black smoke (RR 1.030, 95% CI 0.979 to 1.084) and NO2, though the latter only in cold seasons (RR 1.080, 95% CI 1.025 to 1.140). No association was observed for O3. The associations between asthma admissions and NO2 in adults and SO2 in children were independent of black smoke. CONCLUSIONS: The evidence of an association between air pollution at current urban levels and emergency room visits for asthma has been extended to Europe. In addition to particles, NO2 and SO2--by themselves or as a constituent of a pollution mixture--may be important in asthma exacerbations in European cities.

Adolescent↗
PubMed1997

Air pollution and daily admissions for chronic obstructive pulmonary disease in 6 European cities: results from the APHEA project.

We investigated the short-term effects of air pollution on hospital admissions for chronic obstructive pulmonary disease (COPD) in Europe. As part of a European project (Air Pollution and Health, a European Approach (APHEA)), we analysed data from the cities of Amsterdam, Barcelona, London, Milan, Paris and Rotterdam, using a standardized approach to data eligibility and statistical analysis. Relative risks for daily COPD admissions were obtained using Poisson regression, controlling for: seasonal and other cycles; influenza epidemics; day of the week; temperature; humidity and autocorrelation. Summary effects for each pollutant were estimated as the mean of each city's regression coefficients weighted by the inverse of the variance, allowing for additional between-cities variance, as necessary. For all ages, the relative risks (95% confidence limits (95% CL)) for a 50 microg x m(-3) increase in daily mean level of pollutant (lagged 1-3 days) were (95% CL): sulphur dioxide 1.02 (0.98, 1.06); black smoke 1.04 (1.01, 1.06); total suspended particulates 1.02 (1.00, 1.05), nitrogen dioxide 1.02 (1.00, 1.05) and ozone (8 h) 1.04 (1.02, 1.07). The results confirm that air pollution is associated with daily admissions for chronic obstructive pulmonary disease in European cities with widely varying climates. The results for particles and ozone are broadly consistent with those from North America, though the coefficients for particles are substantially smaller. Overall, the evidence points to a causal relationship but the mechanisms of action, exposure response relationships and pollutant interactions remain unclear.

Air Pollution↗
PubMed1997

[The assessment of population exposure to atmospheric air pollution].

The air pollution concentrations of SO2 and suspended particulate matter in 1993 in one Polish city Poznan and over entire Poland have been modeled and mapped. The data for Poznan were obtained during special epidemiological study by means of a dense network of passive samples and the data for Poland were obtained from the routine network operated by Sanitary Epidemiological Stations. The modeling employed the kriging method of ARC/INFO computer package. It was found that about 1/3 of Polish population was exposed to the SO2 and/or SPM level that exceeded annual recommended values. In Poznan 25% of children aged 8-9 years were exposed to SO2 level above 100 during heating season 1992/1993.

Air Pollution↗
PubMed1996

Short term effects of air pollution on health: a European approach using epidemiologic time series data: the APHEA protocol.

BACKGROUND AND OBJECTIVES: Results from several studies over the past five years have shown that the current levels of pollutants in Europe and North America have adverse short term effects on health. The APHEA project aims to quantifying these in Europe, using standardised methodology. The project protocol and analytical methodology are presented here. DESIGN: Daily time series data were gathered for several air pollutants (sulphur dioxide; particulate matter, measured as total particles or as the particle fraction with an aerodynamic diameter smaller than a certain cut off, or as black smoke; nitrogen dioxide; and ozone) and health outcomes (the total and cause specific number of deaths and emergency hospital admissions). The data included fulfilled the quality criteria set by the APHEA protocol. SETTING: Fifteen European cities from 10 different countries with a total population over 25 million. METHODOLOGY: The APHEA collaborative group decided on a specific methodological procedure to control for confounding effects and evaluate the hypothesis. At the same time there was sufficient flexibility to allow local characteristics to be taken into account. The procedure included modelling of all potential confounding factors (that is, seasonal and long term patterns, meteorological factors, day of the week, holidays, and other unusual events), choosing the "best" air pollution models, and applying diagnostic tools to check the adequacy of the models. The final analysis used autoregressive Poisson models allowing for overdispersion. Effects were reported as relative risks contrasting defined increases in the corresponding pollutant levels. Each participating group applied the analyses to their own data. CONCLUSIONS: This methodology enabled results from many different European settings to be considered collectively. It represented the best available compromise between feasibility, comparability, and local adaptibility when using aggregated time series data not originally collected for the purpose of epidemiological studies.

Air Pollutants↗
PubMed1996

Short term effect of air pollution on mortality in Polish urban populations--what is different?

STUDY OBJECTIVE: To assess, within the multinational European Community funded APHEA project, the relationship between daily ambient air pollution with sulphur dioxide (SO2) and black smoke (BS) and the daily number of deaths from all causes except external, from cardiovascular diseases, and from respiratory diseases taking into account several possible confounding factors. DESIGN: Time series analysis with the application of Poisson regression to the counts of daily number of deaths from selected causes over several years. Data were obtained from the computer files of individual death records in four Polish cities. Criteria developed for all the centres participating in the project were applied to the process of model building. SETTING: Four Polish cities - Cracow (period 1977-89), Lodz (1977-90), Poznan (1983-90), and Wroclaw (1979-89). SUBJECTS: Permanent residents of the cities who died in a city of residence or in a surrounding region during the study period. MAIN RESULTS: There were significant positive associations between mortality from all causes excluding external ones and SO2 and BS in Cracow and in Lodz and between mortality from cardiovascular diseases and SO2 in Cracow alone. In other cities the association was either non-significant or significant but in the opposite direction. No significant positive association was found between respiratory deaths and these pollutants. CONCLUSIONS: Short term effect of air pollution on mortality in Polish urban population cannot be ignored. However, differences observed between the cities suggest that the association may be not so straightforward and therefore there is a need of further studies to identify additional factors that may modify and confound the association.

Air Pollution↗