Simone M. Santos

Associação entre fatores contextuais e auto-avaliação de saúde: uma revisão sistemática de estudos multinível

The influence of residential characteristics on self-rated health has received little research attention, especially in Brazil. This study summarizes the available evidence on the association between contextual factors and self-rated health, using a systematic review of articles published from January 1995 to August 2005. We searched for the terms neighbourhood or neighborhood, ecological, contextual, environment, and community, combined with self-rated health, self-reported health, and multilevel or hierarchical in digital bases. Most of the 18 reviewed studies analyzed socioeconomic indicators, while some investigated psychosocial variables and a few included physical environmental indicators. Spatial units of reference varied from census tracts to States. Differences among scales of contextual analysis and several indicators, with different categories, were identified. The associations corroborate the hypothesis that neighborhood context influences self-rated health, beyond the effect of individual factors. Physical and psychosocial neighborhood characteristics are important contextual factors in the determination of self-rated health. Worse socioeconomic neighborhood conditions have a negative effect on health, thereby increasing the odds of worse self-rated health.

Inter-relacionamento de dados ambientais e de saúde: análise de risco à saúde aplicada ao abastecimento de água no Rio de Janeiro utilizando Sistemas de Informações Geográficas

Exposure assessment of population groups is based on linkage of environmental and health data. This relationship can be hard to establish due to spatial and temporal lags in data sets. GIS can be used as a basis for organizing health-related and environmental data sets. We examined potential health risk in the Rio de Janeiro city water supply based on the overlay of information layers containing data on the presence and quality of water supply services. We used census tracts as the primary georeferenced data, since they contain information on how households are supplied, water supply pipes, sources, and reservoirs, and water quality according to the monitoring program. Population groups exposed to risks were located and quantified using spatial operations among these layers and adopting different risk criteria. The main problems related to water supply are located on the northern slope of the Tijuca Mountain Range and in the western area of the city of Rio, where the population relies on alternative water supply sources. The different origins, objectives, and structures of data have to be analyzed critically, and GIS can be used as a data validation tool as well as an instrument for detailed identification of inconsistencies.

Detecção de aglomerados espaciais de óbitos por causas violentas em Porto Alegre, Rio Grande do Sul, Brasil, 1996

O objetivo desse artigo e analisar a distribuicao espacial das residencias de vitimas das principais causas violentas de morte no municipio de Porto Alegre em 1996. A violencia tem importante impacto na saude da populacao dos centros urbanos brasileiros, devendo integrar a agenda das acoes de saude. A incorporacao de ferramentas de analise espacial pode enriquecer os meios de vigilância e prevencao. Foram geo-referenciados os locais de residencia das vitimas de acidente de transporte, homicidio e suicidio utilizando-se o Sistema de Informacoes Geograficas. Os padroes de pontos dos eventos e o de densidade populacional foram analisados por alisamento Kernel e comparados visualmente. Certas areas de maior concentracao dos eventos sao similares a distribuicao da populacao; nas demais areas de alta concentracao, diferenciam-se entre si e delimitam microareas de risco. Vitimas de homicidio concentram-se na periferia da area mais urbanizada; acidentes de transporte concentram-se em areas mistas de residencias e comercio; a distribuicao dos suicidios e mais homogenea. A identificacao das populacoes vulneraveis fornece informacoes importantes para a implementacao de politicas de promocao da saude e de prevencao.

Mortality spatial patterns and socioeconomic differences in the city of Rio de Janeiro

Health situation analysis has been used to understand complex health processes and to contribute to decision-making in public policies. This paper analyzes the spatial relationship between mortality patterns in the city of Rio de Janeiro (1996-1998) and socioeconomic profiles of neighborhoods. Mortality data were collected from the Municipal Health Department and population data were obtained from the National Census Bureau (IBGE) (1991 and 1996). Neighborhoods were aggregated through the K-means cluster method into 4 homogeneous socioeconomic groups, and the mortality indicators distribution was analyzed by different strata. General mortality, circulatory disease mortality, mortality from poorly defined causes, and mortality from violent causes all displayed large differences among socioeconomic groups. The spatial pattern of the socioeconomic strata allowed the identification of different living conditions, which involved specific mortality patterns. Higher socioeconomic strata presented low mortality figures for all causes.

Colocando dados no mapa: a escolha da unidade espacial de agregação e integração de bases de dados em saúde e ambiente através do geoprocessamento

Os Sistemas de Informacoes Geograficas (SIG) podem ser utilizados como ambiente de consolidacao e analise de grandes bases de dados sobre saude e ambiente. No entanto, e necessario um esforco para compatibilizar tecnicas de enderecamento de dados, o que implica na adequacao entre bases de dados e base cartografica. Neste trabalho sao discutidos alguns problemas encontrados no georeferenciamento de dados de saude e ambiente, bem como alguns criterios para a escolha da unidade espacial minima de agregacao de dados, permitindo a qualidade e intercâmbio entre camadas de informacoes. O caso do abastecimento de agua no municipio do Rio de Janeiro pode ser utilizado como exemplo de avaliacao de condicoes de saude em micro-areas, onde diversas fontes de informacao com diferentes caracteristicas construtivas sao dispostas em mapas e interrelacionadas no espaco na forma de camadas.

Demarcation of local neighborhoods to study relations between contextual factors and health.

BackgroundSeveral studies have highlighted the importance of collective social factors for population health. One of the major challenges is an adequate definition of the spatial units of analysis which present properties potentially related to the target outcomes. Political and administrative divisions of urban areas are the most commonly used definition, although they suffer limitations in their ability to fully express the neighborhoods as social and spatial units.ObjectiveThis study presents a proposal for defining the boundaries of local neighborhoods in Rio de Janeiro city. Local neighborhoods are constructed by means of aggregation of contiguous census tracts which are homogeneous regarding socioeconomic indicators.MethodologyLocal neighborhoods were created using the SKATER method (TerraView software). Criteria used for socioeconomic homogeneity were based on four census tract indicators (income, education, persons per household, and percentage of population in the 0-4-year age bracket) considering a minimum population of 5,000 people living in each local neighborhood. The process took into account the geographic boundaries between administrative neighborhoods (a political-administrative division larger than a local neighborhood, but smaller than a borough) and natural geographic barriers.ResultsThe original 8,145 census tracts were collapsed into 794 local neighborhoods, distributed along 158 administrative neighborhoods. Local neighborhoods contained a mean of 10 census tracts, and there were an average of five local neighborhoods per administrative neighborhood.The local neighborhood units demarcated in this study are less socioeconomically heterogeneous than the administrative neighborhoods and provide a means for decreasing the well-known statistical variability of indicators based on census tracts. The local neighborhoods were able to distinguish between different areas within administrative neighborhoods, particularly in relation to squatter settlements.ConclusionAlthough the literature on neighborhood and health is increasing, little attention has been paid to criteria for demarcating neighborhoods. The proposed method is well-structured, available in open-access software, and easily reproducible, so we expect that new experiments will be conducted to evaluate its potential use in other settings. The method is thus a potentially important contribution to research on intra-urban differentials, particularly concerning contextual factors and their implications for different health outcomes.

Detection of Wolbachia DNA in blood from dogs infected with Dirofilaria immitis.

Dirofilaria immitis is the causative agent of heartworm disease in canines and felines, and pulmonary dirofilariasis in man. It harbors a symbiotic intracellular bacterium from the genus Wolbachia that plays an important role in its biology and contributes to the inflammatory pathology of the heartworm. This endosymbiont is sensitive to the tetracycline family of antibiotics prompting its use in the treatment of filariasis. To track Wolbachia during treatment, primers were designed based on the FtsZ gene from Wolbachia. These primers amplify a single PCR product with the expected size from DNA samples derived from various species of worms that harbor Wolbachia (D. immitis, Brugia malayi and Brugia pahangy). The detection limit of Wolbachia DNA in the assay was 80 pg of D. immitis DNA. Furthermore, the primer set successfully amplified the expected PCR product using blood samples from dogs harboring the heartworm and circulating microfilariae.

Adaptacao transcultural e confiabilidade de medidas de caracteristicas autorreferidas de vizinhanca no ELSA-Brasil

OBJETIVO: Descrever o processo de adaptacao de escalas de medida de caracteristicas de vizinhanca para o portugues brasileiro. METODOS: As dimensoes abordadas foram coesao social, ambiente propicio para atividade fisica, disponibilidade de alimentos saudaveis, seguranca em relacao a crimes, violencia percebida e vitimizacao. No processo de adaptacao foram avaliados aspectos de equivalencia entre as escalas originais e respectivas versoes para o portugues. A confiabilidade teste-reteste foi avaliada em submostra de 261 participantes do Estudo Longitudinal de Saude do Adulto (ELSA-Brasil) que responderam ao mesmo questionario em dois momentos distintos em um intervalo de tempo de sete a 14 dias entre as duas aplicacoes. RESULTADOS: Os aspectos de equivalencia avaliados mostraram-se adequados. O coeficiente de correlacao intraclasse variou entre 0,83 (IC95% 0,78;0,87) para Coesao Social e 0,90 (IC95% 0,87;0,92) para Ambiente para Atividade Fisica. As escalas apresentaram consistencia interna (alfa de Cronbach) que variaram entre 0,60 e 0,84. CONCLUSOES: As medidas autorreferidas de caracteristicas de vizinhanca tiveram reprodutibilidade muito boa e boa consistencia interna. Os resultados sugerem que essas escalas podem ser utilizadas em estudos com populacao brasileira que apresente caracteristicas similares aquelas do ELSA-Brasil.

Aspectos éticos em estudos longitudinais: o caso do ELSA-Brasil

The debate about ethics in research with human beings has historically emphasized experimental studies because of their greater potential to harm the subjects involved. However, observational studies also include risks and relevant questions to be discussed. This article aims to present and discuss the ethical aspects involved in the implementation of ELSA-Brasil, a longitudinal multicenter study, with public funding, in which the research subjects and investigators are employees of the same institutions. The procedures adopted to meet the ethical requirements and commitments are described, as well as the casuistics that guided the actions according to their guiding principles (beneficence, autonomy and social justice). We present some moral problems that required consideration of risks and benefits at the confluence with the studys objectives, and we conclude with comments on the peculiarities and the potential benefits of a longitudinal study.

Assessment of participation bias in cohort studies: systematic review and meta-regression analysis

The proportion of non-participation in cohort studies, if associated with both the exposure and the probability of occurrence of the event, can introduce bias in the estimates of interest. The aim of this study is to evaluate the impact of participation and its characteristics in longitudinal studies. A systematic review (MEDLINE, Scopus and Web of Science) for articles describing the proportion of participation in the baseline of cohort studies was performed. Among the 2,964 initially identified, 50 were selected. The average proportion of participation was 64.7%. Using a meta-regression model with mixed effects, only age, year of baseline contact and study region (borderline) were associated with participation. Considering the decrease in participation in recent years, and the cost of cohort studies, it is essential to gather information to assess the potential for non-participation, before committing resources. Finally, journals should require the presentation of this information in the papers.