Izabel Marcilio

Hospitalizações por causas respiratórias e cardiovasculares associadas à contaminação atmosférica no Município de São Paulo, Brasil

The recognition that current air pollution levels cause harmful health effects makes the definition of the air quality regulatory process imperative. This study examines the association between exposure to air pollution and hospital admissions in the city of Sao Paulo, aiming to support the development of measures to reduce such health risks. The authors conducted an ecological time series study of hospital admissions for respiratory and cardiovascular diseases in children and the elderly in relation to daily air pollution levels, using generalized additive Poisson regression models. All air pollutants except ozone showed a statistically significant association with admissions for respiratory and cardiovascular diseases. An increase of 10µg/m3 in fine particulate matter was associated with a 4.6% increase in asthma admissions in children and a 4.3% increase in admissions for chronic obstructive pulmonary disease and 1.5% for ischemic heart disease in the elderly. These associations are consistent with a large body of literature in this area and indicate that the current air pollution levels in Sao Paulo have an important negative impact on the populations health.

Forecasting Daily Emergency Department Visits Using Calendar Variables and Ambient Temperature Readings

OBJECTIVES This study aimed to develop different models to forecast the daily number of patients seeking emergency department (ED) care in a general hospital according to calendar variables and ambient temperature readings and to compare the models in terms of forecasting accuracy. METHODS The authors developed and tested six different models of ED patient visits using total daily counts of patient visits to an ED in Sao Paulo, Brazil, from January 1, 2008, to December 31, 2010. The first 33 months of the data set were used to develop the ED patient visits forecasting models (the training set), leaving the last 3 months to measure each models forecasting accuracy by the mean absolute percentage error (MAPE). Forecasting models were developed using three different time-series analysis methods: generalized linear models (GLM), generalized estimating equations (GEE), and seasonal autoregressive integrated moving average (SARIMA). For each method, models were explored with and without the effect of mean daily temperature as a predictive variable. RESULTS The daily mean number of ED visits was 389, ranging from 166 to 613. Data showed a weekly seasonal distribution, with highest patient volumes on Mondays and lowest patient volumes on weekends. There was little variation in daily visits by month. GLM and GEE models showed better forecasting accuracy than SARIMA models. For instance, the MAPEs from GLM models and GEE models at the first month of forecasting (October 2012) were 11.5 and 10.8% (models with and without control for the temperature effect, respectively), while the MAPEs from SARIMA models were 12.8 and 11.7%. For all models, controlling for the effect of temperature resulted in worse or similar forecasting ability than models with calendar variables alone, and forecasting accuracy was better for the short-term horizon (7 days in advance) than for the longer term (30 days in advance). CONCLUSIONS This study indicates that time-series models can be developed to provide forecasts of daily ED patient visits, and forecasting ability was dependent on the type of model employed and the length of the time horizon being predicted. In this setting, GLM and GEE models showed better accuracy than SARIMA models. Including information about ambient temperature in the models did not improve forecasting accuracy. Forecasting models based on calendar variables alone did in general detect patterns of daily variability in ED volume and thus could be used for developing an automated system for better planning of personnel resources.

Quantifying the impact of air pollution on the urban population of Brazil

This study aimed to quantify air pollution impact on morbidity and mortality in the Brazilian urban population using locally generated impact factors. Concentration-response coefficients were used to estimate the number of hospitalizations and deaths attributable to air pollution in seven Brazilian cities. Poisson regression coefficients (beta) were obtained from time-series studies conducted in Brazil. The study included individuals 65 years old and over and children under five. More than 600 deaths a year from respiratory causes in the elderly and 47 in children were attributable to mean air pollution levels, corresponding to 4.9% and 5.5% of all deaths from respiratory causes in these age groups. More than 4,000 hospital admissions for respiratory conditions were also attributable to air pollution. These results quantitatively demonstrate the currently observed contribution of air pollution to mortality and hospitalizations in Brazilian cities. Such assessment is thought to help support the planning of surveillance and control activities for air pollution in these and similar areas.

Adult mortality from leukemia, brain cancer, amyotrophic lateral sclerosis and magnetic fields from power lines: a case-control study in Brazil

Recent publications renewed interest in assessing potential health risks for subjects living close to transmission lines. This study aimed at evaluating the association of both distance of home address to the nearest overhead transmission line and of the calculated magnetic fields from the power lines and mortality from leukemia, brain cancer, and amyotrophic lateral sclerosis. We carried out a death certificate based case-control study accessing adult mortality in the Metropolitan Region of São Paulo, in Brazil. Analysis included 1,857 cases of leukemia, 2,357 of brain cancer, 367 of amyotrophic lateral sclerosis, and 4,706 as controls. An increased risk for mortality from leukemia among adults living at closer distances to transmission lines compared to those living further then 400 m was found. Risk was higher for subjects that lived within 50 m from power lines (OR=1.47; 95% CI=0.99-2.18). Similarly, a small increase in leukemia mortality was observed among adults living in houses with higher calculated magnetic fields (OR=1.61; 95% CI=0.91-2.86 for those exposed to magnetic fields >0.3 µT). No increase was seen for brain tumours or amyotrophic lateral sclerosis. Our findings are suggestive of a higher risk for leukemia among subjects living closer to transmission lines, and for those living at homes with higher calculated magnetic fields, although the risk was limited to lower voltage lines.

Campos magnéticos de frequência extremamente baixa e efeitos na saúde: revisão da literatura

A partir da publicacao, em 1979, dos resultados de um estudo que apontava para o aumento do risco de leucemia em criancas associado a exposicao a campos magneticos, o interesse pelo tema vem aumentando, e diversos estudos foram publicados. O objetivo desta revisao e apresentar os diferentes metodos utilizados na avaliacao da exposicao aos campos magneticos de frequencia extremamente baixa, bem como as dificuldades enfrentadas na quantificacao dessa exposicao, alem de relatar os resultados de estudos epidemiologicos publicados nos ultimos 10 anos. A falta de um modelo fisiopatologico que explique uma possivel influencia dos campos magneticos na saude e a dificuldade para quantificar a exposicao tem sido os maiores obstaculos da pesquisa na area. Leucemia e tumores do sistema nervoso central tem sido os efeitos mais estudados. Leucemia em criancas e o desfecho mais consistentemente associado a exposicao a campos magneticos. Estudos mais recentes apontam a associacao entre esclerose lateral amiotrofica e campos magneticos.

Desigualdade social e exposição a campos magnéticos na Região Metropolitana de São Paulo

OBJETIVO: Estimar a prevalencia de exposicao aos campos magneticos gerados por linhas de transmissao (LT) e caracterizar a populacao exposta. METODOS: Informacoes sobre LT da Regiao Metropolitana de Sao Paulo foram fornecidas pelas concessionarias de energia e mapeadas usando sistema de informacao geografica (SIG). Dados demograficos e socioeconomicos foram obtidos por meio do Censo 2000 e incluidos no SIG em outra camada. Foram considerados expostos os domicilios e seus habitantes localizados a uma distância da LT suficiente para gerar um campo magnetico 0,3 µT (microteslas). A prevalencia foi estimada por meio da area de corredores de exposicao ao longo das LT. A largura dos corredores de exposicao se baseou em duas abordagens: uma consistiu em larguras pre-definidas pela tensao da LT e a outra por meio de calculo do campo magnetico. As informacoes socioeconomicas entre expostos e nao expostos foram comparadas pela aplicacao do teste de duas proporcoes (α= 5%). RESULTADOS: Nos corredores com larguras pre-definidas a prevalencia de exposicao foi de 2,4% e nos corredores calculados, foi de 1,4%. Ambos os metodos indicaram maior prevalencia de exposicao na populacao mais jovem, com menores niveis de renda e escolaridade (p < 0,001). CONCLUSOES: A prevalencia de exposicao aos campos magneticos gerados por LT na regiao metropolitana de Sao Paulo ficou abaixo do observado em outros paises. Os resultados indicam desigualdade na exposicao aos campos magneticos nessa area urbana, com maiores riscos as populacoes vulneraveis, como criancas e pessoas socioeconomicamente desfavorecidas.OBJECTIVE To estimate the prevalence of exposure to magnetic fields generated by transmission lines (TL) and characterize the exposed population. METHODS Information about TL in the metropolitan region of São Paulo, Southeastern Brazil, was provided by the electricity companies and mapped out using geographic information system (GIS). Demographic and socioeconomic data were obtained from the 2000 Census and added to the GIS in another layer. Households and their inhabitants that were located at a distance from the TL that was sufficient to generate a magnetic field 0.3 microT (microteslas) were deemed to be exposed. The prevalence was estimated according to the area of the corridors of exposure along the TL. Two approaches were used to delimit the corridor width: one consisted of widths that were predefined by the TL voltage, and the other consisted of calculation of the magnetic field. The socioeconomic information on the exposed and non-exposed populations were compared by applying the two-proportion test (alpha= 5%). RESULTS In the corridors with predefined widths, the prevalence of exposure was 2.4%, and in the calculated corridors, the prevalence was 1.4%. Both methods indicated higher prevalence of exposure among the younger population, and among individuals with lower education and income levels (p < 0.001). CONCLUSIONS The prevalence of exposure to magnetic fields generated by TL in the metropolitan region of São Paulo was lower than what has been observed in other countries. The results indicate inequality in the exposure to magnetic fields in this urban area, with greater risk to vulnerable populations such as children and socioeconomically less favored individuals.

Social inequality and exposure to magnetic fields in the metropolitan region of São Paulo, Southeastern Brazil.

OBJETIVO: Estimar a prevalencia de exposicao aos campos magneticos gerados por linhas de transmissao (LT) e caracterizar a populacao exposta. METODOS: Informacoes sobre LT da Regiao Metropolitana de Sao Paulo foram fornecidas pelas concessionarias de energia e mapeadas usando sistema de informacao geografica (SIG). Dados demograficos e socioeconomicos foram obtidos por meio do Censo 2000 e incluidos no SIG em outra camada. Foram considerados expostos os domicilios e seus habitantes localizados a uma distância da LT suficiente para gerar um campo magnetico 0,3 µT (microteslas). A prevalencia foi estimada por meio da area de corredores de exposicao ao longo das LT. A largura dos corredores de exposicao se baseou em duas abordagens: uma consistiu em larguras pre-definidas pela tensao da LT e a outra por meio de calculo do campo magnetico. As informacoes socioeconomicas entre expostos e nao expostos foram comparadas pela aplicacao do teste de duas proporcoes (α= 5%). RESULTADOS: Nos corredores com larguras pre-definidas a prevalencia de exposicao foi de 2,4% e nos corredores calculados, foi de 1,4%. Ambos os metodos indicaram maior prevalencia de exposicao na populacao mais jovem, com menores niveis de renda e escolaridade (p < 0,001). CONCLUSOES: A prevalencia de exposicao aos campos magneticos gerados por LT na regiao metropolitana de Sao Paulo ficou abaixo do observado em outros paises. Os resultados indicam desigualdade na exposicao aos campos magneticos nessa area urbana, com maiores riscos as populacoes vulneraveis, como criancas e pessoas socioeconomicamente desfavorecidas.OBJECTIVE To estimate the prevalence of exposure to magnetic fields generated by transmission lines (TL) and characterize the exposed population. METHODS Information about TL in the metropolitan region of São Paulo, Southeastern Brazil, was provided by the electricity companies and mapped out using geographic information system (GIS). Demographic and socioeconomic data were obtained from the 2000 Census and added to the GIS in another layer. Households and their inhabitants that were located at a distance from the TL that was sufficient to generate a magnetic field 0.3 microT (microteslas) were deemed to be exposed. The prevalence was estimated according to the area of the corridors of exposure along the TL. Two approaches were used to delimit the corridor width: one consisted of widths that were predefined by the TL voltage, and the other consisted of calculation of the magnetic field. The socioeconomic information on the exposed and non-exposed populations were compared by applying the two-proportion test (alpha= 5%). RESULTS In the corridors with predefined widths, the prevalence of exposure was 2.4%, and in the calculated corridors, the prevalence was 1.4%. Both methods indicated higher prevalence of exposure among the younger population, and among individuals with lower education and income levels (p < 0.001). CONCLUSIONS The prevalence of exposure to magnetic fields generated by TL in the metropolitan region of São Paulo was lower than what has been observed in other countries. The results indicate inequality in the exposure to magnetic fields in this urban area, with greater risk to vulnerable populations such as children and socioeconomically less favored individuals.

Desigualdad social y exposición a campos magnéticos en la región metropolitana de Sao Paulo

OBJETIVO: Estimar a prevalencia de exposicao aos campos magneticos gerados por linhas de transmissao (LT) e caracterizar a populacao exposta. METODOS: Informacoes sobre LT da Regiao Metropolitana de Sao Paulo foram fornecidas pelas concessionarias de energia e mapeadas usando sistema de informacao geografica (SIG). Dados demograficos e socioeconomicos foram obtidos por meio do Censo 2000 e incluidos no SIG em outra camada. Foram considerados expostos os domicilios e seus habitantes localizados a uma distância da LT suficiente para gerar um campo magnetico 0,3 µT (microteslas). A prevalencia foi estimada por meio da area de corredores de exposicao ao longo das LT. A largura dos corredores de exposicao se baseou em duas abordagens: uma consistiu em larguras pre-definidas pela tensao da LT e a outra por meio de calculo do campo magnetico. As informacoes socioeconomicas entre expostos e nao expostos foram comparadas pela aplicacao do teste de duas proporcoes (α= 5%). RESULTADOS: Nos corredores com larguras pre-definidas a prevalencia de exposicao foi de 2,4% e nos corredores calculados, foi de 1,4%. Ambos os metodos indicaram maior prevalencia de exposicao na populacao mais jovem, com menores niveis de renda e escolaridade (p < 0,001). CONCLUSOES: A prevalencia de exposicao aos campos magneticos gerados por LT na regiao metropolitana de Sao Paulo ficou abaixo do observado em outros paises. Os resultados indicam desigualdade na exposicao aos campos magneticos nessa area urbana, com maiores riscos as populacoes vulneraveis, como criancas e pessoas socioeconomicamente desfavorecidas.OBJECTIVE To estimate the prevalence of exposure to magnetic fields generated by transmission lines (TL) and characterize the exposed population. METHODS Information about TL in the metropolitan region of São Paulo, Southeastern Brazil, was provided by the electricity companies and mapped out using geographic information system (GIS). Demographic and socioeconomic data were obtained from the 2000 Census and added to the GIS in another layer. Households and their inhabitants that were located at a distance from the TL that was sufficient to generate a magnetic field 0.3 microT (microteslas) were deemed to be exposed. The prevalence was estimated according to the area of the corridors of exposure along the TL. Two approaches were used to delimit the corridor width: one consisted of widths that were predefined by the TL voltage, and the other consisted of calculation of the magnetic field. The socioeconomic information on the exposed and non-exposed populations were compared by applying the two-proportion test (alpha= 5%). RESULTS In the corridors with predefined widths, the prevalence of exposure was 2.4%, and in the calculated corridors, the prevalence was 1.4%. Both methods indicated higher prevalence of exposure among the younger population, and among individuals with lower education and income levels (p < 0.001). CONCLUSIONS The prevalence of exposure to magnetic fields generated by TL in the metropolitan region of São Paulo was lower than what has been observed in other countries. The results indicate inequality in the exposure to magnetic fields in this urban area, with greater risk to vulnerable populations such as children and socioeconomically less favored individuals.