Bayesian Modeling for Nonstationary Spatial Point Process via Spatial Deformations.

Many techniques have been proposed to model space-varying observation processes with a nonstationary spatial covariance structure and/or anisotropy, usually on a geostatistical framework. Nevertheless, there is an increasing interest in point process applications, and methodologies that take nonstationarity into account are welcomed. In this sense, this work proposes an extension of a class of spatial Cox process using spatial deformation. The proposed method enables the deformation behavior to be data-driven, through a multivariate latent Gaussian process. Inference leads to intractable posterior distributions that are approximated via MCMC. The convergence of algorithms based on the Metropolis-Hastings steps proved to be slow, and the computational efficiency of the Bayesian updating scheme was improved by adopting Hamiltonian Monte Carlo (HMC) methods. Our proposal was also compared against an alternative anisotropic formulation. Studies based on synthetic data provided empirical evidence of the benefit brought by the adoption of nonstationarity through our anisotropic structure. A real data application was conducted on the spatial spread of the Spodoptera frugiperda pest in a corn-producing agricultural area in southern Brazil. Once again, the proposed method demonstrated its benefit over alternatives.

Ventilator-associated pneumonia prevention by education and two combined bedside strategies.

OBJECTIVE: The objective of the study was to reduce the ventilator-associated pneumonia (VAP) incidence rates through a rational prevention program. DESIGN: The study was a non-controlled clinical trial with a set of interventions in mechanically ventilated patients from April 2006 until June 2008. Pneumonia rates were analyzed as time series and their mean risks of development were compared before and after the interventions with a non-concurrent cohort using the same time frame (January 2004-March 2006). SETTING: The study was conducted in a 14-bed medical intensive care unit of private general hospital in Rio de Janeiro, Brazil. PARTICIPANTS: The study included invasively ventilated patients (n = 224; intervention group) compared with 294 controls (historical cohort). INTERVENTIONS: An educational module about VAP prevention was introduced at the start of the trial (April 2006). A bundle checklist was used daily concomitantly with a standardized oral care in all patients afterwards. Main outcome measure The main outcome measure was reduction in VAP incidence rates. RESULTS: The observed mean rate before the intervention was 18.6 ± 7.8/1000 ventilator-days (95% CI 8.7-14.9), decreasing to 11.8 ± 7.8/1000 ventilator-days (95% CI 15.5-21.7) (P = 0.002) after the interventions. Under the adoption of non-informative prior distributions for the parameters of the proposed statistical model, there was a 70% posterior probability in favor of the hypothesis of risk reduction associated with the interventions, regardless their seasonality or secular trends. There was a 38% relative risk reduction. CONCLUSIONS: A reduction in VAP rates and on their risk after a set of preventive tools was observed. However, some other co-interventions not related to the primary interventions may have contributed to these results.

ArboAlvo: stratification method for territorial receptivity to urban arboviruses.

OBJECTIVE: To present the urban arboviruses (dengue, zika and chikungunya) stratification methodology by the territorial receptivity Index, an instrument for the surveillance and control of these diseases, which considers the heterogeneity of an intra-municipal territory. METHODS: Ecological study that uses as unit of analysis the areas covered by health centers in Belo Horizonte. For the development of a territorial receptivity index, indicators of socio-environmental determination of urban arboviruses were selected in order to integrate the analysis of main components. The resulting components were weighted by the analytic hierarchy process and combined via map algebra. RESULTS: The territorial receptivity index showed great heterogeneity of urban infrastructure conditions. The areas classified with high and very high receptivity correspond to approximately 33% of the occupied area and are mainly concentrated in the administrative planning regions of East, Northeast, North, West, and Barreiro, especially in areas surrounding the municipality. When the density of dengue cases and Aedes eggs, from 2016, were superimposed with the stratification by the index of territorial receptivity to urban arboviruses, areas of very high receptivity had a high density of cases and Aedes eggs - higher than that observed in other areas of the city, which corresponds to a very small percentage of the municipal territory (13.5%). CONCLUSION: The analyses indicate the need for the development of adequate surveillance and control actions for each context, overcoming the logic of homogeneous allocation throughout the territory.

BR-EMS 2021 life table for the Brazilian insured population / Tábuas de mortalidade BR-EMS 2021 do mercado segurador brasileiro / Tabla de vida BR-EMS 2021 para la población asegurada brasileña

Abstract This article presents the Brazilian private insurance market's actuarial life tables, BR- EMS 2021. Using Bayesian inference on the parameters of the Heligman- Pollard law of mortality and data from 23 insurance groups over 15 years, totaling 3.5 billion registers, the data were corrected through a two hidden-layer neural network. The resulting tables show that the insured population exhibits lower mortality rates than the general Brazilian population, even lower than the national populations of well-developed countries such as the USA. Moreover, besides the expected gender gap in mortality rates, there is a clear distance between the death and survivorship insurance coverage groups. Likewise, the insured population characteristics mitigate well-known regional structural discrepancies in the Brazilian population, indicating that being part of the selected population of insured individuals is thus associated with a more effective protection against death than other outstanding factors such as geographic region of residence.

Resumo Este artigo apresenta as tábuas de vida do mercado de seguros privados brasileiro, BR-EMS 2021. Os dados obtidos de 23 grupos seguradores ao longo de 15 anos, totalizando 3,5 bilhões de registros, foram corrigidos por meio de rede neural com duas camadas ocultas. Usando a inferência bayesiana para estimar os parâmetros sob a lei de mortalidade Heligman-Pollard, as tábuas obtidas mostram que a população segurada apresenta probabilidades de morte mais baixas do que a população brasileira em geral e até mesmo em relação a populações nacionais de países desenvolvidos, como os EUA. Além da esperada diferença de gênero nas taxas de mortalidade, há uma clara distância entre as probabilidades de morte dos grupos de cobertura de risco e cobertura de sobrevivência. Da mesma forma, é demonstrado que as tábuas regionais da população segurada não apresentam as discrepâncias regionais conhecidas no Brasil, indicando que fazer parte da população selecionada de segurados está associado a um fator de proteção mais eficaz do que outros fatores, como a região geográfica de residência.

Resumen Este artículo presenta las tablas de vida del mercado de seguros privados brasileño, BR-EMS 2021. Los datos, obtenidos de 23 grupos de seguros a lo largo de 15 años, totalizando 3,5 mil millones de registros, fueron corregidos usando una red neuronal con dos capas ocultas. Mediante la inferencia bayesiana para estimar los parámetros bajo la ley de mortalidad de Heligman-Pollard, las tablas obtenidas muestran que la población asegurada tiene tasas de mortalidad más bajas que la población general brasileña e incluso más bajas que las poblaciones nacionales de países desarrollados, como los Estados Unidos de Norteamérica. Además de la diferencia de género esperada en las tasas de mortalidad, hay una clara distinción entre las tablas de grupos de cobertura de riesgo y cobertura de sobrevivientes. Asimismo, se demuestra que las tablas regionales de población asegurada no presentan las conocidas discrepancias estructurales regionales en Brasil, lo que indica que participar de la población de asegurados está asociado con una protección contra la muerte más efectiva que otros factores como la región geográfica de residencia.

ArboAlvo: stratification method for territorial receptivity to urban arboviruses / ArboAlvo: método de estratificação da receptividade territorial às arboviroses urbanas

ABSTRACT OBJECTIVE To present the urban arboviruses (dengue, zika and chikungunya) stratification methodology by the territorial receptivity Index, an instrument for the surveillance and control of these diseases, which considers the heterogeneity of an intra-municipal territory. METHODS Ecological study that uses as unit of analysis the areas covered by health centers in Belo Horizonte. For the development of a territorial receptivity index, indicators of socio-environmental determination of urban arboviruses were selected in order to integrate the analysis of main components. The resulting components were weighted by the analytic hierarchy process and combined via map algebra. RESULTS The territorial receptivity index showed great heterogeneity of urban infrastructure conditions. The areas classified with high and very high receptivity correspond to approximately 33% of the occupied area and are mainly concentrated in the administrative planning regions of East, Northeast, North, West, and Barreiro, especially in areas surrounding the municipality. When the density of dengue cases and Aedes eggs, from 2016, were superimposed with the stratification by the index of territorial receptivity to urban arboviruses, areas of very high receptivity had a high density of cases and Aedes eggs - higher than that observed in other areas of the city, which corresponds to a very small percentage of the municipal territory (13.5%). CONCLUSION The analyses indicate the need for the development of adequate surveillance and control actions for each context, overcoming the logic of homogeneous allocation throughout the territory.

RESUMO OBJETIVO Apresentar a metodologia de estratificação das arboviroses urbanas (dengue, zika e chikungunya) pelo índice de receptividade territorial, instrumento de vigilância e controle dessas doenças que considera a heterogeneidade territorial intramunicipal. MÉTODOS Estudo ecológico que utiliza como unidade de análise as áreas de abrangência dos centros de saúde de Belo Horizonte (MG). Para a construção do índice de receptividade territorial foram selecionados indicadores de determinação socioambiental das arboviroses urbanas a fim de integrar à análise de componentes principais. As componentes resultantes foram ponderadas por análise de processos hierárquicos e agregadas por meio de álgebra de mapas. RESULTADOS O índice de receptividade territorial evidenciou grande heterogeneidade das condições de infraestrutura urbana. As áreas classificadas como alta e muito alta receptividade correspondem a aproximadamente 33% da área ocupada e se concentram sobretudo nas regiões de planejamento administrativo Leste, Nordeste, Norte, Oeste e Barreiro, principalmente em áreas limítrofes do município. Quando sobrepostas à densidade de casos de dengue e de ovos de Aedes em 2016, a estratificação pelo índice de receptividade territorial às arboviroses urbanas demonstra que áreas de muito alta receptividade apresentam uma densidade de casos, bem como de ovos de Aedes superior àquela observada nas demais áreas da cidade, o que corresponde a um percentual bastante reduzido do território municipal (13,5%). CONCLUSÕES As análises indicam a necessidade do desenvolvimento de ações de vigilância e controle adequadas para cada contexto, superando, assim, a lógica de alocação homogênea em todo o território.

[Study on blindness: mortality of patients with chronic kidney disease during non-elective hemodialysis]. / Ensaio sobre a cegueira: mortalidade de pacientes com doença renal crônica em hemodiálise de emergência.

Chronic kidney disease (CKD) leads to renal failure and the need for renal replacement therapy (RRT). Secondary prevention may postpone CKD for many years. This retrospective study sought to analyze prognostic factors and estimate the mortality of patients with CKD secondary to diabetes mellitus and to hypertension that initiate RRT through non-elective hemodialysis at an emergency hospital unit in Rio de Janeiro, from hospital admission until transfer to referral units. The mortality rate was 35.1%. The study detected a significant difference between the survival curves according to disease etiology (log-rank and Peto, p=0.02) and the presence of functional arteriovenous fistulae (log-rank, p=0.0099; Peto, p=0.0090). Multivariate analysis (Cox model) revealed a 7% increase in the risk of death (p=0.002) by one-year increment in age; the presence of a functional fistule was associated to an 81% reduction in the risk of death (p=0.03). About one third of patients with CKD followed by hypertension or diabetes that initiate renal replacement therapy through non-elective hemodialysis die before being transferred to a referral unit, indicating low access to secondary prevention in CKD, including surgery for arteriovenous fistula creation.

Ensaio sobre a cegueira: mortalidade de pacientes com doença renal crônica em hemodiálise de emergência / Study on blindness: mortality of patients with chronic kidney disease during non-elective hemodialysis

A doença renal crônica (DRC) leva à falência renal e à necessidade de terapia renal substitutiva (TRS). A prevenção secundária pode retardar em muitos anos a evolução da doença. O presente estudo, retrospectivo, objetivou analisar os fatores prognósticos e estimar a mortalidade de portadores de doença renal crônica (DRC) secundária à hipertensão ou diabetes que iniciam a TRS por hemodiálise de emergência, desde a admissão hospitalar até a transferência para clínica-satélite ou óbito, no Rio de Janeiro. A taxa de mortalidade foi de 35,1%. Houve diferença significativa entre as curvas de sobrevida até o óbito, por doença de base (log-rank e Peto, p = 0,02) e por presença de fístula funcional (log-rank, p = 0,0099; Peto, p = 0,0090). A análise multivariada (modelo de Cox) mostrou aumento no risco de óbito de 7% (p = 0,002) por ano de idade; a presença de fístula funcional foi associada a uma redução de 81% no risco (p = 0,03). Conclui-se que um terço dos pacientes portadores de DRC por hipertensão e diabetes, que iniciam a TRS de forma não planejada, morrem no período entre a admissão hospitalar e a transferência para clínicas-satélites, o que indica baixo acesso à prevenção secundária na DRC, inclusive à cirurgia para a confecção da fístula arteriovenosa.

Chronic kidney disease (CKD) leads to renal failure and the need for renal replacement therapy (RRT). Secondary prevention may postpone CKD for many years. This retrospective study sought to analyze prognostic factors and estimate the mortality of patients with CKD secondary to diabetes mellitus and to hypertension that initiate RRT through non-elective hemodialysis at an emergency hospital unit in Rio de Janeiro, from hospital admission until transfer to referral units. The mortality rate was 35.1%. The study detected a significant difference between the survival curves according to disease etiology (log-rank and Peto, p=0.02) and the presence of functional arteriovenous fistulae (log-rank, p=0.0099; Peto, p=0.0090). Multivariate analysis (Cox model) revealed a 7% increase in the risk of death (p=0.002) by one-year increment in age; the presence of a functional fistule was associated to an 81% reduction in the risk of death (p=0.03). About one third of patients with CKD followed by hypertension or diabetes that initiate renal replacement therapy through non-elective hemodialysis die before being transferred to a referral unit, indicating low access to secondary prevention in CKD, including surgery for arteriovenous fistula creation.

Seminário 'Prevenção do Parto Prematuro Associado à Infecção Intrauterina: marcadores biológicos e ensaio clínico de probióticos' - Letícia Krauss Silva (Coord.)

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