Análise espacial do padrão de introdução e disseminação da dengue nos municípios do Espírito Santo

O número de municípios infestados pelo Aedes aegypti no Estado do Espírito Santo vem aumentando gradativamente, levando a altas taxas de incidência de dengue ao longo dos anos. Apesar das tentativas de combate à doença, esta se tornou uma das maiores preocupações na saúde pública do Estado. Este estudo se propõe a descrever a dinâmica da expansão da doença no Estado a partir da associação entre variáveis ambientais e populacionais, utilizando dados operacionalizados por meio de técnicas de geoprocessamento. O estudo utilizou como fonte de dados a infestação pelo mosquito vetor e o coeficiente de incidência da doença, as distâncias rodoviárias intermunicipais do Estado, a altitude dos municípios e as variáveis geoclimáticas (temperatura e suficiência de água), incorporadas a uma ferramenta operacional, as Unidades Naturais do Espírito Santo (UNES), representadas em um único mapa operacionalizado em Sistema de Informação Geográfica (SIG), obtido a partir do Sistema Integrado de Bases Georreferenciadas do Estado do Espírito Santo. Para análise dos dados, foi realizada a Regressão de Poisson para os dados de incidência de dengue e Regressão Logística para os de infestação pelo vetor. Em seguida, os dados de infestação pelo mosquito e incidência de dengue foram georreferenciados, utilizando como ferramenta operacional o SIG ArcGIS versão 9.2. Observou-se que a pluviosidade é um fator que contribui para o surgimento de mosquito em áreas não infestadas. Altas temperaturas contribuem para um alto coeficiente de incidência de dengue nos municípios capixabas. A variável distância em relação a municípios populosos é um fator de proteção para a incidência da doença. A grande variabilidade encontrada nos dados, que não é explicada pelas variáveis utilizadas no modelo para incidência da doença, reforça a premissa de que a dengue é condicionada pela interação dinâmica entre muitas variáveis que o estudo não abordou. A espacialização dos dados de infestação pelo mosquito e incidência de dengue e as Zonas Naturais do ES permitiu a visualização da influência das variáveis estatisticamente significantes nos modelos utilizados no padrão da introdução e disseminação da doença no Estado.

Factors related to inadequate cervical cancer screening in two Brazilian state capitals

OBJECTIVE:To analyze factors associated with cervical cancer screening failure. METHODS:Population-based cross-sectional study with self-weighted two-stage cluster sampling conducted in the cities of Fortaleza (Northeastern Brazil) and Rio de Janeiro (Southeastern Brazil) in 2002. Subjects were women aged 25-59 years in the last three years prior to the study. Data were analyzed through Poisson regression using a hierarchical model. RESULTS: The proportion of women who did not undergo the Pap smear test in Fortaleza and Rio de Janeiro was 19.1% (95% CI: 16.1;22.1) and 16.5% (95% CI: 14.1;18.9), respectively. Higher prevalence ratios of cervical cancer screening failure in both cities were seen among women with low education and low per capita income, old age, unmarried, who never underwent mammography, clinical breast examination, and blood glucose and cholesterol level testing. Smokers also had lower screening rates compared to non-smoker women and this difference was only statistically significant in Rio de Janeiro. CONCLUSIONS:The study findings point to the need of intervention focusing particularly women in worse socioeconomic conditions and access to healthcare, old-aged and unmarried. Education activities must prioritize screening of asymptomatic women and early diagnosis for symptomatic women and access to adequate diagnostic methods and treatment should be provided.

Risk factors for cesarean section by category of health service

OBJECTIVE: To analyze the rate of cesarean section and differences in risk factors by category of health service, either public or private. METHODS: A cross-sectional study was carried out including all pregnant women in labor admitted to hospitals in the city of Rio Grande, Southern Brazil, between January 1 and December 31, 2007. A pre-coded and pre-tested questionnaire was used to collect on social, demographic, obstetric and newborn care information. Two regression models were constructed: one for public users and the other one for private ones. Poisson regression was used in each model in the multivariate analysis. Prevalence rates and 95% confidence intervals were calculated for each adjusted factor. RESULTS: The rate of cesarean section was 43% and 86% among public and private users. Sociodemographic factors and twin births have a more significant impact among public users as well as number of pregnancies (25% vs. 13% reduction in public and private users, respectively) and previous cesarean section (86% vs. 24% increase in public and private users, respectively). Prenatal care visits and hospital admissions affected the outcome only in women users of public services. CONCLUSIONS: Cesarean section rates were high in both groups studied, but it was twice as high among women cared in the private sector. Associated factors differ in magnitude by category of service used.

Growth patterns in early childhood and the onset of menarche before age twelve

OBJECTIVE: To examine the relationship between growth patterns in early childhood and the onset of menarche before age 12. METHODS: The study included 2,083 women from a birth cohort study conducted in the city of Pelotas, Southern Brazil, starting in 1982. Anthropometric, behavioral, and pregnancy-related variables were collected through home interviews. Statistical analyses were performed using Pearson's chi-square and chi-square test for linear trends. A multivariable analysis was carried out using Poisson regression based on a hierarchical model. RESULTS: Mean age of menarche was 12.4 years old and the prevalence of menarche before age 12 was 24.3%. Higher weight-for-age, height-for-age, and weight-for-height z-scores at 19.4 and 43.1 months of age were associated with linear tendencies of increased prevalence and relative risks of the onset of menarche before age 12. Girls who experienced rapid growth in weight-for-age z-score from birth to 19.4 months of age and in weight-for-age or height-for-age z-scores from 19.4 to 43.1 months of age also showed higher risk of menarche before age 12. Higher risk was seen when rapid growth in weight-for-age z-score was seen during these age intervals and the highest risk was found among those in the first tertile of Williams' curve at birth. Rapid growth in weight-for-height z-score was not associated with menarche before age 12. CONCLUSIONS: Menarche is affected by nutritional status and growth patterns during early childhood. Preventing overweight and obesity during early childhood and keeping a "normal" growth pattern seem crucial for the prevention of health conditions during adulthood.

Factors associated to medicine use among children from the 2004 Pelotas Birth Cohort (Brazil)

OBJECTIVE: To identify factors associated to medicine use among children from the 2004 Pelotas Birth Cohort, Brazil. METHODS: Prospective study to evaluate medicine use in children aged 3, 12 and 24 months regardless of the reasons, therapeutic indication or class. The study included 3,985 children followed up at three months of age, 3,907 at 12 months, and 3,868 at the last follow-up time of 24 months. Mothers were interviewed to collect information on medicine use during the recall period of 15 days prior to the interview. The outcome was studied according to sociodemographic and perinatal variables, mother's perception of child's health and breastfeeding status. Crude and adjusted analyses were performed by Poisson regression following a hierarchical model. RESULTS: The prevalence of medicine use ranged from 55% to 65% in the three follow-ups. After controlling for confounders, some variables remained associated to medicine use only at the three-month follow-up with greatest use among children of younger mothers, those children who had intrapartum complications, low birthweight, were never breastfed and were admitted to a hospital. Greatest medicine use was also associated with being a firstborn child at 3 and 12 months; mother's perception of their child health as fair or poor and children whose mothers have private health insurance at 12 and 24 months; highest maternal education level at all follow-up times. CONCLUSIONS: Different variables influence medicine use among children during the first two years of life and they change as the child ages especially maternal factors and those associated to the child's health problems.

Association between tooth loss and obesity in Brazilian adults: a population-based study

OBJECTIVE: To examine the association between tooth loss and general and central obesity among adults. METHODS: Population-based cross-sectional study with 1,720 adults aged 20 to 59 years from Florianópolis, Southern Brazil. Home interviews were performed and anthropometric measures were taken. Information on sociodemographic data, self-reported diabetes, self-reported number of teeth, central obesity (waist circumference [WC] > 88 cm in women and > 102 cm in men) and general obesity (body mass index [BMI] ≥ 30 kg/m²) was collected. We used multivariable Poisson regression models to assess the association between general and central obesity and tooth loss after controlling for confounders. We also performed simple and multiple linear regressions by using BMI and WC as continuous variables. Interaction between age and tooth loss was also assessed. RESULTS: The mean BMI was 25.9 kg/m² (95%CI 25.6;26.2) in men and 25.4 kg/m2 (95%CI 25.0;25.7) in women. The mean WC was 79.3 cm (95%CI 78.4;80.1) in men and 88.4 cm (95%CI 87.6;89.2) in women. A positive association was found between the presence of less than 10 teeth in at least one arch and increased mean BMI and WC after adjusting for education level, self-reported diabetes, gender and monthly per capita income. However, this association was lost when the variable age was included in the model. The prevalence of general obesity was 50% higher in those with less than 10 teeth in at least one arch when compared with those with 10 or more teeth in both arches after adjusting for education level, self-reported diabetes and monthly per capita family income. However, the statistical significance was lost after controlling for age. CONCLUSIONS: Obesity was associated with number of teeth, though it depended on the participants' age groups.

Principal components and generalized linear modeling in the correlation between hospital admissions and air pollution

OBJECTIVE To analyze the association between concentrations of air pollutants and admissions for respiratory causes in children. METHODS Ecological time series study. Daily figures for hospital admissions of children aged < 6, and daily concentrations of air pollutants (PM10, SO2, NO2, O3 and CO) were analyzed in the Região da Grande Vitória, ES, Southeastern Brazil, from January 2005 to December 2010. For statistical analysis, two techniques were combined: Poisson regression with generalized additive models and principal model component analysis. Those analysis techniques complemented each other and provided more significant estimates in the estimation of relative risk. The models were adjusted for temporal trend, seasonality, day of the week, meteorological factors and autocorrelation. In the final adjustment of the model, it was necessary to include models of the Autoregressive Moving Average Models (p, q) type in the residuals in order to eliminate the autocorrelation structures present in the components. RESULTS For every 10:49 μg/m3 increase (interquartile range) in levels of the pollutant PM10 there was a 3.0% increase in the relative risk estimated using the generalized additive model analysis of main components-seasonal autoregressive – while in the usual generalized additive model, the estimate was 2.0%. CONCLUSIONS Compared to the usual generalized additive model, in general, the proposed aspect of generalized additive model − principal component analysis, showed better results in estimating relative risk and quality of fit.

Determinants of using pacifier and bottle feeding

OBJECTIVE To analyze the factors associated with the use of pacifiers and/or bottle feeding in infants aged under one year.METHODS This is a cross-sectional study with 34,366 children and using data from the database of the 2nd Nationwide Survey of Breastfeeding Prevalence performed in the Brazilian capitals and Federal District in 2008. Cluster sampling was used. The questionnaire included questions about the use of artificial nipples in the last 24 hours. The analysis considered three outcomes: exclusive use of pacifier, exclusive use of bottle feeding, and use of artificial nipples (pacifier and bottle feeding). Prevalence ratios were obtained using Poisson regression with robust variance following a hierarchical model.RESULTS The following factors were associated with exclusive use of the pacifier: mother working outside the home, primiparity, child was not breastfed within the first hour, and child had consumed tea on the first day at home. The following factors were associated with exclusive use of bottle feeding: mother working outside the home, primiparity, low birth weight, child not breastfed within the first hour, and child had consumed milk formula and tea on the first day at home. The following factors were associated with use of artificial nipples (pacifier and bottle feeding): mother working outside the home, primiparity, cesarean delivery, the male gender, low birth weight, born in a hospital not accredited as “baby friendly”, required health baby monitoring in the Primary Health Care Unit (PR = 0.91), and child had consumed milk formula, water, or tea on the first day at home.CONCLUSIONS This study identified profiles of exclusive users of pacifiers, bottle feeding, and both. The provided information can guide preventive practices for child health.

Women with HIV: gender violence and suicidal ideation

OBJECTIVE To analyze the relationship between gender violence and suicidal ideation in women with HIV. METHODS A cross-sectional study with 161 users of specialized HIV/AIDS care services. The study investigated the presence of gender violence through the Brazilian version of the World Health Organization Violence against Women instrument, and suicidal ideation through the Suicidal Ideation Questionnaire. Statistical analyses were performed with the SPSS software, using the Chi-square test and Poisson multiple regression model. RESULTS Eighty-two women with HIV reported suicidal ideation (50.0%), 78 (95.0%) of who had suffered gender violence. Age at first sexual intercourse < 15 years old, high number of children, poverty, living with HIV for long, and presence of violence were statistically associated with suicidal ideation. Women who suffered gender violence showed 5.7 times more risk of manifesting suicidal ideation. CONCLUSIONS Women with HIV showed a high prevalence to gender violence and suicidal ideation. Understanding the relationship between these two grievances may contribute to the comprehensive care of these women and implementation of actions to prevent violence and suicide.

Factors associated with dietary supplement use by people who exercise at gyms

OBJECTIVE To assess the factors associated with the use of dietary supplements by people who exercise at gyms.METHODS A cross-sectional study with a sample defined by convenience, considering the number of gyms registered in the Conselho Regional de Educação Física (Regional Council of Physical Education) of Sao Luis, MA, Northeastern Brazil, from July 2011 to July 2012. The final sample comprised 723 individuals who exercise at gyms. The dependent variable was supplement use, and the explanatory variables were length of time and motivation of the physical exercises, duration, goal and self-perception of training, weekly frequency of gym attendance, sex, age, educational attainment, self-perception of body weight, smoking and self-perception of diet. The association between variables was analysed by hierarchical Poisson regression based on a theoretical model.RESULTS Supplement use was reported by 64.7% of the participants. Most of the sample was male (52.6%). The most frequent age group was 20 to 39 years (74.4%). Most participants (46.1%) had been exercising for over a year. The following variables were associated with supplement use: self-perceiving body weight as below ideal (p < 0.001), smoking (p < 0.001), exercising for 7 to 12 months (p = 0.028) or more than one year (p < 0.001), spending more than two hours at the gym (p = 0.051), and perceiving training as moderate (p = 0.024) or intense (p = 0.001).CONCLUSIONS The use of supplements lacks proper professional guidance, being motivated by individuals unsatisfied with their low body weight and who perceive their workout as intense, which raises the need for monitoring this population.

Past and present: conditions of life during childhood and mortality of older adults

ABSTRACT OBJECTIVE: To analyze whether socioeconomic and health conditions during childhood are associated with mortality during old age. METHODS: Data were extracted from the SABE Study (Saúde, Bem-estar e Envelhecimento – Health, Welfare and Aging), which were performed in 2000 and 2006. The sample consisted of 2004 (1,355 living and 649 dead) older adults. The statistical analysis was performed based on Poisson regression models, taking into account the time variation of risk observed. Older adults’ demographic characteristics and life conditions were evaluated, as were the socioeconomic and lifestyle conditions they acquired during their adult life. RESULTS: Only the area of residence during childhood (rural or urban) remained as a factor associated with mortality at advanced ages. However, this association lost significance when the variables acquired during adulthood were added to the model. CONCLUSIONS: Despite the information regarding the conditions during childhood being limited and perhaps not accurately measure the socioeconomic status and health in the first years of life, the findings of this study suggest that improving the environmental conditions of children and creating opportunities during early adulthood may contribute to greater survival rates for those of more advanced years.

Acute Kidney Injury after Pediatric Cardiac Surgery: Risk Factors and Outcomes. Proposal for a Predictive Model

Objectives: To characterize the epidemiology and risk factors for acute kidney injury (AKI) after pediatric cardiac surgery in our center, to determine its association with poor short-term outcomes, and to develop a logistic regression model that will predict the risk of AKI for the study population. Methods: This single-center, retrospective study included consecutive pediatric patients with congenital heart disease who underwent cardiac surgery between January 2010 and December 2012. Exclusion criteria were a history of renal disease, dialysis or renal transplantation. Results: Of the 325 patients included, median age three years (1 day---18 years), AKI occurred in 40 (12.3%) on the first postoperative day. Overall mortality was 13 (4%), nine of whom were in the AKI group. AKI was significantly associated with length of intensive care unit stay, length of mechanical ventilation and in-hospital death (p<0.01). Patients’ age and postoperative serum creatinine, blood urea nitrogen and lactate levels were included in the logistic regression model as predictor variables. The model accurately predicted AKI in this population, with a maximum combined sensitivity of 82.1% and specificity of 75.4%. Conclusions: AKI is common and is associated with poor short-term outcomes in this setting. Younger age and higher postoperative serum creatinine, blood urea nitrogen and lactate levels were powerful predictors of renal injury in this population. The proposed model could be a useful tool for risk stratification of these patients.

Spatio-temporal patterns of tuberculosis incidence in Ribeirão Preto, State of São Paulo, southeast Brazil, and their relationship with social vulnerability: a Bayesian analysis

INTRODUCTION: The purpose of this ecological study was to evaluate the urban spatial and temporal distribution of tuberculosis (TB) in Ribeirão Preto, State of São Paulo, southeast Brazil, between 2006 and 2009 and to evaluate its relationship with factors of social vulnerability such as income and education level. METHODS: We evaluated data from TBWeb, an electronic notification system for TB cases. Measures of social vulnerability were obtained from the SEADE Foundation, and information about the number of inhabitants, education and income of the households were obtained from Brazilian Institute of Geography and Statistics. Statistical analyses were conducted by a Bayesian regression model assuming a Poisson distribution for the observed new cases of TB in each area. A conditional autoregressive structure was used for the spatial covariance structure. RESULTS: The Bayesian model confirmed the spatial heterogeneity of TB distribution in Ribeirão Preto, identifying areas with elevated risk and the effects of social vulnerability on the disease. We demonstrated that the rate of TB was correlated with the measures of income, education and social vulnerability. However, we observed areas with low vulnerability and high education and income, but with high estimated TB rates. CONCLUSIONS: The study identified areas with different risks for TB, given that the public health system deals with the characteristics of each region individually and prioritizes those that present a higher propensity to risk of TB. Complex relationships may exist between TB incidence and a wide range of environmental and intrinsic factors, which need to be studied in future research.

Credit default swap (CDS) prediction model & trading strategy

This project focuses on the study of different explanatory models for the behavior of CDS security, such as Fixed-Effect Model, GLS Random-Effect Model, Pooled OLS and Quantile Regression Model. After determining the best fitness model, trading strategies with long and short positions in CDS have been developed. Due to some specifications of CDS, I conclude that the quantile regression is the most efficient model to estimate the data. The P&L and Sharpe Ratio of the strategy are analyzed using a backtesting analogy, where I conclude that, mainly for non-financial companies, the model allows traders to take advantage of and profit from arbitrages.

Association between LDL-C, Non HDL-C, and Apolipoprotein B Levels with Coronary Plaque Regression

Background:Previous reports have inferred a linear relationship between LDL-C and changes in coronary plaque volume (CPV) measured by intravascular ultrasound. However, these publications included a small number of studies and did not explore other lipid markers.Objective:To assess the association between changes in lipid markers and regression of CPV using published data.Methods:We collected data from the control, placebo and intervention arms in studies that compared the effect of lipidlowering treatments on CPV, and from the placebo and control arms in studies that tested drugs that did not affect lipids. Baseline and final measurements of plaque volume, expressed in mm3, were extracted and the percentage changes after the interventions were calculated. Performing three linear regression analyses, we assessed the relationship between percentage and absolute changes in lipid markers and percentage variations in CPV.Results:Twenty-seven studies were selected. Correlations between percentage changes in LDL-C, non-HDL-C, and apolipoprotein B (ApoB) and percentage changes in CPV were moderate (r = 0.48, r = 0.47, and r = 0.44, respectively). Correlations between absolute differences in LDL-C, non‑HDL-C, and ApoB with percentage differences in CPV were stronger (r = 0.57, r = 0.52, and r = 0.79). The linear regression model showed a statistically significant association between a reduction in lipid markers and regression of plaque volume.Conclusion:A significant association between changes in different atherogenic particles and regression of CPV was observed. The absolute reduction in ApoB showed the strongest correlation with coronary plaque regression.