Cut-off points in the waist:height ratio for the prediction of insulin resistance, second stage of sexual maturation in Brazilian adolescents.

The objective of this study was verify the best waist:height ratio (WHtR) cut-off points for the prediction of insulin resistance (IR) according to stage of sexual maturation in Brazilian adolescents. Data were analysed from 37 759 adolescents between 12 and 17 years of age, of both sexes, participating in the ERICA study on cardiovascular risk factors in adolescents ('Estudo de Riscos Cardiovasculares em Adolescentes - ERICA'). The following variables were included sex, age and sexual maturity according to the Tanner stage, waist circumference, height, WHtR, fasting insulin and fasting blood sugar so as to obtain the homeostasis model assessment-estimated insulin resistance (HOMA-IR). We constructed an Receiver Operating characteristic (ROC) curve for each group in order to determine the best WHtR cut-off points for the sample stratified by sex and stratified by sex and sexual maturation stage. The female sex corresponded to 60% of the sample, with a mean age of 14·7 years (sd ± 0·08 years) and 13·1 % had IR. The prediction of IR through the WHtR indicator was better for boys, where all the areas under the ROC curve were superior to 0·70. When stratifying by sex alone, the best WHtR cut-off points found were equal to 0·45 for girls and 0·44 for boys. When stratifying by Tanner maturation stages, the cut-off points were reduced with advancing sexual maturation in the male group, while the opposite occurred in the female group. Among Brazilian adolescents, WHtR is a good predictor of IR evaluated by HOMA-IR, but different cut-off points should be adopted according to sex and sexual maturation stage.

Dietary patterns among adolescent freshmen attending a public university / Padrões alimentares de adolescentes recém-ingressos em uma universidade pública

ABSTRACT Objective To identify the association between dietary patterns and nutritional status in adolescent freshmen at a public university in Northeastern Brazil. Methods In this cross-sectional study anthropometric variables, body composition and food intake were collected and assessed using the food frequency questionnaire. Dietary patterns were evaluated through factor analysis using the principal component extraction method. Results Two dietary patterns were identified: "Western" pattern, consisting of foods with high energy density and low nutritional value, and the "traditional Brazilian" pattern, with foods from Brazilian cuisine such as rice, beans, corn, roots and tubers, fruits, greens and vegetables. The multiple regression analysis revealed a negative association between the "traditional Brazilian" pattern and both excess weight and body fat in females. Conclusion A healthy dietary pattern with typical local cuisine foods can offer protection to health and should be encouraged.

RESUMO Objetivo Identificar a associação entre padrões alimentares e estado nutricional em adolescentes recém-ingressos em uma universidade pública do Nordeste brasileiro. Métodos Neste estudo transversal foram coletados dados antropométricos, composição corporal e consumo alimentar, verificado pelo questionário de frequência alimentar. Os padrões alimentares foram derivados através da análise fatorial pelo método de extração de componentes principais. Resultados Dois padrões alimentares foram identificados: o padrão "Ocidental", composto por alimentos de elevada densidade energética e de baixo valor nutricional, e o padrão "tradicional brasileiro", contendo alimentos da culinária brasileira como arroz, feijão, milho, raízes e tubérculos, frutas, verduras e legumes. A análise de regressão múltipla mostrou associação negativa entre o excesso de peso e de gordura corporal e o padrão alimentar "tradicional brasileiro" no sexo feminino. Conclusão Um padrão alimentar saudável e com alimentos típicos da culinária local pode conferir proteção à saúde, devendo ser incentivado.

Tracking of Dietary Patterns in the Secondary Prevention of Cardiovascular Disease after a Nutritional Intervention Program-A Randomized Clinical Trial.

Individuals with a history of previous cardiovascular events have an increased risk of mortality and morbidity, so adherence to a healthy dietary pattern is essential. We aimed to evaluate and compare dietary patterns between the control and the experimental group from the BALANCE Program. A total of 2360 individuals aged 45 years or older with previous cardiovascular disease were included. The individuals were randomized into two groups: intervention (dietary prescription with nutritional recommendations, nutritional education program based on playful strategies, suggestions of typical and accessible Brazilian foods and intensive monitoring) and control (conventional nutritional counseling). The dietary patterns were identified using factor analysis with the principal component extraction method, and the t-Student tests and ANOVA test were performed to evaluate the associated factors. Four dietary patterns were identified for both groups: "Traditional", "Snack", "Western", "Cardioprotective". There was an increase in the variances of the "Cardioprotective" pattern in both groups. Regarding the "Western" pattern, there was a significant reduction in the variances of the experimental group (10.63% vs. 8.14%). Both groups had improvements in eating habits, especially in the first year of follow-up. The greater increase in adherence to the traditional and cardioprotective pattern in the experimental group justifies the initiative of the BALANCE program.

Padrões alimentares e fatores de risco cardiovasculares em adolescentes / Dietary patterns and cardiovascular risk factors in adolescents

Introdução: os hábitos alimentares são formados, boa parte, no período da adolescência, sendo esta fase considerada um risco para o desenvolvimento de fatores de risco cardiovascular, como o excesso de peso e dislipidemia, os quais podem ter implicações imediatas e a longo prazo na saúde dos adolescentes. Objetivo: identificar os padrões alimentares e avaliar, prospectivamente, seu impacto no estado nutricional e no perfil lipídico de adolescentes. Métodos: esta tese foi composta de três artigos, um de corte transversal e dois de corte longitudinal, todos utilizando dados do Estudo Longitudinal sobre Comportamento Sedentário, Atividade Física, Hábitos Alimentares e Saúde de Adolescentes - Estudo LONCAAFS. Foram analisados 1431 adolescentes em 2014, 1178 adolescentes em 2015, 959 em 2016 e, por fim, 773 adolescentes em 2017, pertencentes a rede pública de ensino de João Pessoa, cidade do Nordeste brasileiro. Para a obtenção de dados de consumo alimentar, aplicou-se o recordatório de 24 horas, duplicado em 30% da amostra, em todos os anos. Os padrões alimentares foram identificados por meio de análise fatorial exploratória por componentes principais. O estado nutricional foi obtido e classificado de acordo com a recomendação da Organização Mundial de Saúde, por meio do índice de massa corporal (IMC) para o sexo e a idade. As concentrações de colesterol total (CT), lipoproteína de alta densidade (HDL) e triglicerídeos (TG) foram determinadas pelo método de turbidimetria e a lipoproteína de baixa densidade (LDL) foi determinada pela equação de Friedwald, sendo posteriormente classificados de acordo com a Diretriz Brasileira de Dislipidemia e Aterosclerose. Foram coletados dados socioeconômicos, sobre comportamento sedentário e atividade física. As associações entre os padrões alimentares e estado nutricional, perfil lipídico e variáveis de interesse foram realizadas por equações de estimativas generalizadas (GEE). Resultados: a análise longitudinal do presente estudo identificou três padrões alimentares distintos que se mantiveram ao longo do estudo: o padrão "Tradicional", composto principalmente por alimentos típicos da dieta tradicional brasileira, como o arroz e o feijão, mas também por alimentos típicos da cultura nordestina, como mandioca e cuscuz; um padrão "Lanches" caracterizado pelo consumo de pães, manteigas e margarinas, queijos, carnes processadas e café; e um padrão "Ocidental" caracterizado pelo consumo de alimentos com alta densidade energética e pobres em nutrientes. Adolescentes do sexo masculino apresentaram uma maior redução no escore-z do IMC, ao longo do estudo. A prevalência de dislipidemia foi elevada, independentemente da idade. O sexo feminino foi positivamente associado a níveis elevados de CT e LDL e o sexo masculino com níveis baixos de HDL. O padrão alimentar "Ocidental" foi positivamente associado ao escore-z do IMC, independente do sexo e do nível de atividade física, ao longo do tempo e adolescentes com maior aderência aos padrões alimentares "lanches" e "ocidental" apresentaram maior chance de alterações nos níveis séricos de colesterol total. Conclusão: Estes resultados indicam que um padrão alimentar que é rico em densidade de energia, alto teor de gordura e açucares, além de baixo teor de fibra contribui para um estado nutricional e perfil lipídico que sinaliza risco para o desenvolvimento de doenças cardiovasculares nestes adolescentes. Além disso, os resultados desta tese sugerem a necessidade de ações de saúde pública multidisciplinar que estimulem mudanças nos hábitos alimentares e estilo de vida, prevenindo, desta forma, o desenvolvimento de doenças cardiovasculares na vida adulta.

Introdução: eating habits are mostly formed during adolescence, and this phase is considered a risk for the development of cardiovascular risk factors, such as overweight and dyslipidemia, which may have immediate and long-term implications for the health of adolescents. Objetivo: identify dietary patterns and prospectively assess their impact on nutritional status and lipid profile in adolescents. Métodos: this thesis was composed of three articles, one cross-sectional and two longitudinal, all using data from the Longitudinal Study on Sedentary Behavior, Physical Activity, Eating Habits and Adolescent Health - LONCAAFS Study. We analyzed 1431 adolescents in 2014, 1178 adolescents in 2015, 959 in 2016 and, finally, 773 adolescents in 2017, belonging to the public school system of João Pessoa, city of Northeast Brazil. To obtain food consumption data, the 24-hour recall was applied, duplicated in 30% of the sample, every year. Dietary patterns were identified by exploratory factor analysis by principal components. Nutritional status was obtained and classified according to the World Health Organization recommendation through BMI for gender and age. The concentrations of total cholesterol (TC), high density lipoprotein (HDL) and triglycerides (TG) were determined by turbidimetry method and low density lipoprotein (LDL) was determined by Friedwald's equation, and were later classified according to the Brazilian Dyslipidemia and Atherosclerosis Guideline. Socioeconomic data, on sedentary behavior and physical activity were collected. Associations between dietary patterns and nutritional status, lipid profile and variables of interest were made by generalized estimation equations (GEE). Resultados: the longitudinal analysis of the present study identified three distinct dietary patterns that were maintained throughout the study: the "Traditional" pattern, consisting mainly of typical foods of the traditional Brazilian diet, such as rice and beans, but also typical foods of the Northeastern culture, as cassava and couscous; a "Sandwuiches" pattern characterized for the consumption of breads, butters and margarines, cheeses, processed meats and coffees; and a "Western" pattern characterized for the consumption of high energy density and nutrient poor foods. Male adolescents showed a greater reduction in BMI z-score throughout the study. The prevalence of dyslipidemia was high, regardless of age. Females were positively associated with elevated TC and LDL levels and males with low HDL levels. The "Western" dietary pattern was positively associated with BMI z-score, regardless of gender and level of physical activity over time and adolescents with greater adherence to "Sandwuiches" and "Western" dietary patterns were more likely to have changes in serum total cholesterol levels. Conclusão: these results indicate that a dietary pattern that is rich in energy density, high fat and sugars, and low fiber contributes to a nutritional status and lipid profile that signals risk for the development of cardiovascular disease in these adolescents. In addition, the results of this thesis suggest the need for multidisciplinary public health actions that stimulate changes in eating habits and lifestyle, thus preventing the development of cardiovascular disease in adulthood.