Peso al nacer en el noroeste argentino. Comparación con una referencia nacional y un estándar internacional / Birth weight in the Northwest region of Argentina. Comparison with a national reference and an international standard

Introducción. El tamaño al nacer se encuentra sujeto a influencias genéticas y ambientales; la altura geográfica es muy influyente. El peso al nacer (PN) es el indicador más utilizado para evaluarlo; existen diferentes estándares y referencias. Debido a la variabilidad de la distribución del PN en relación con la altura en la provincia de Jujuy (Argentina), este trabajo analiza la distribución percentilar del PN para tierras altas (TA) y tierras bajas (TB) jujeñas según edad gestacional (EG) y sexo, y su comparación con una referencia nacional y el estándar internacional INTERGROWTH-21st (IG-21). Población y métodos. Se analizaron los registros de 78 524 nacidos vivos en Jujuy en el período 20092014. Utilizando el método LMS, se estimaron los percentiles 3, 10, 50, 90 y 97 de PN/EG por sexo, para TA (≥2000 msnm), TB (<2000 msnm) y el total provincial, y se compararon gráficamente con la referencia poblacional argentina de Urquía y el estándar IG-21. La significación estadística se determinó mediante la prueba de Wilcoxon. Resultados. El PN en Jujuy presentó distribución heterogénea, con diferencias estadísticamente significativas (p <0,05) entre TB y TA. Al comparar con la referencia nacional y el estándar IG-21, se observaron diferencias por altitud, principalmente en los percentiles 90 y 97 para ambas regiones, y en los percentiles 3 y 10 en TA comparados con el estándar. Conclusiones. Se observó variabilidad de la distribución del PN asociada a la altura geográfica, por lo que, para evaluar el crecimiento intrauterino, resulta fundamental incluir la EG y el contexto donde transcurre la gestación.

Introduction. Size at birth is subject to genetic and environmental influences; altitude is highly influential. Birth weight (BW) is the most widely used indicator to assess size at birth; different standards and references are available. Due to the variability in BW distribution in relation to altitude in the province of Jujuy (Argentina), the purpose of this study is to analyze the percentile distribution of BW in the highlands (HL) and the lowlands (LL) of Jujuy based on gestational age (GA) and sex and compare it with a national reference and the INTERGROWTH-21 st (IG-21) international standard. Population and methods. The records of 78 524 live births in Jujuy in the 2009­2014 period were analyzed. Using the LMS method, the 3 rd, 10 th, 50 th, 90 th, and 97 th percentiles of BW/GA by sex were estimated for the HL (≥ 2000 MASL), the LL (< 2000 MASL), and the total for Jujuy, and compared with the Argentine population reference by Urquía and the IG-21 standard using growth charts. The statistical significance was established using the Wilcoxon test. Results. BW in Jujuy showed a heterogeneous distribution, with statistically significant differences (p < 0.05) between the LL and the HL. When compared with the national reference and the IG-21 standard, differences in terms of altitude were observed, mainly in the 90 th and 97 th percentiles for both regions and the 3 rd and 10 th percentiles in the HL compared with the international standard. Conclusions. BW distribution varied in association with altitude; therefore, to assess intrauterine growth, it is critical to include GA and the environment in which the pregnancy takes place.

MULT - uma nova referência internacional para avaliação nutricional de crianças e adolescentes / MULT - a new international growth reference to assess the nutritional status of children and adolescents

Introdução: A disponibilidade de várias curvas de crescimento propostas por diversas instituições e modeladas com diferentes populações dificulta a adoção de uma referência internacional. Objetivo: Elaborar uma nova referência internacional e comparar seu desempenho com o de outras curvas de referências já existentes. Métodos: Dados sociodemográficos, antropométricos e de composição corporal de participantes com idades entre zero e 23 anos foram coletados dos inquéritos populacionais: National Health and Nutrition Examination Survey (NHANES), Porto Alegre, Santos, Young Lives: an International Study of Childhood Poverty (YL), Millennium Cohort Study (MCS), Geração XXI (G21), Epidemiological Health Investigation of Teenagers in Porto (EPITeen) e Estudo Longitudinal de Avaliação Nutricional de Adolescentes (ELANA). A nova referência internacional denominada MULT apresentou curvas de altura, índice de massa corporal (IMC) e índice alométrico de massa corporal (IAMC) para a idade construídas por meio do método LMS e o Generalized Additive Models for Location, Scale, and Shape (GAMLSS). A eficiência da referência MULT foi comparada com as das referências internacionais da World Health Organization (WHO), International Task Force Obesity (IOTF) e Centers for Disease Control and Prevention (CDC). A precisão diagnóstica das curvas foi realizada por meio da análise de adiposidade corporal e o risco de sobrepeso na pré-adolescência foi estimado a partir da análise da canalização de crescimento de IMC (CC-IMC). Ademais, uma ferramenta para avaliação nutricional baseada nos valores de referência MULT foi elaborada no Microsoft Excel e disponibilizada online. Resultados: Em comparação com as curvas da WHO, IOTF e CDC, as curvas de altura da MULT mostraram meninos mais altos nos períodos de 61-174 e 196-240 meses, e meninas mais altas nos períodos de 61-147 e 181-240 meses, com relação as de IMC, a MULT apresentou os valores médios mais baixos para as idades de 102-240 meses para os meninos e de 114-220 meses para meninas. Já as de IAMC apresentaram as maiores diferenças nas idades de 138-150 meses para meninos e de 114-132 meses para meninas, coincidindo com a puberdade. As curvas de IAMC apresentaram as melhores performances para diagnosticar obesidade a partir da análise da composição corporal (meninos=0,95;IC95%:0,94- 0,95/meninas=0,92; IC95%:0,92-093) e a análise de risco relativo (RR) apontou que crianças eutróficas durante a infância que aumentaram seu CC-IMC em ≥0,67 e <0,86 apresentaram maior probabilidade de estarem com excesso do peso aos 9,5-13,5 anos [IOTFRR= 2,31;IC95%:1,82-2,93/MULT-RR=2,49;IC95%:2,00-3,09/WHO-RR=2,47; IC95%:1,96- 3,12], em comparação com aquelas que permaneceram dentro do seu canal. Conclusão: Para diagnóstico da obesidade, a referência MULT teve um desempenho melhor entre as referências de IMC, enquanto que as curvas de IAMC da MULT apresentaram o melhor desempenho entre todas, sendo a única capaz de detectar que as meninas apresentavam, proporcionalmente, mais massa de gordura do que os meninos para os mesmos valores de índice. Além disso, a análise da canalização apontou que um aumento no CC-IMC ≥0,67DP durante a infância foi associado a um risco de excesso de peso aos 9,5-13,5 anos. Esses resultados apontam que a referência MULT pode ser uma excelente opção para avaliação nutricional de crianças e adolescentes.

Introduction: The availability of several growth references proposed by different institutions and modeled with different populations complicates the adoption of an international growth reference. Objective: To develop a new international reference and compare its performance with other existing growth references. Methods: Sociodemographic, anthropometric, and body composition data from birth to 23 years old were collected from the population surveys: National Health and Nutrition Examination Survey (NHANES), Porto Alegre, Santos, Young Lives: an International Study of Childhood Poverty (YL), Millennium Cohort Study (MCS), Generation XXI (G21), Epidemiological Health Investigation of Teenagers in Porto (EPITeen), and Longitudinal Study of Nutritional Assessment of Adolescents (ELANA). A new international reference called MULT was developed, which included height, BMI, and allometric body mass index (ABMI) growth charts. These curves were constructed using the LMS method and the generalized additive models for location, scale, and shape (GAMLSS). The efficiency of this reference was compared with the international growth references of the World Health Organization (WHO), International Task Force Obesity (IOTF), and Centers for Disease Control and Prevention (CDC). The diagnostic accuracy of the growth references was assessed through the analysis of body adiposity, and the risk of overweight in pre-adolescence was estimated from the analysis of the BMI growth channeling (BMI-GC). In addition, a nutritional assessment tool based on MULT reference values was developed in Microsoft Excel and made available online. Results: In comparison to the WHO, IOTF, and CDC, the MULT height reference showed taller boys during the periods of 61-174 and 196-240 months, and taller girls during the periods of 61-147 and 181-240 months. Regarding the BMI, the MULT presented the lowest mean values for the ages of 102-240 months for boys and for the ages of 114-220 months for girls. The ABMI reference presented the largest differences at ages 138- 150 months for boys and 114-132 months for girls, coinciding with the pubertal stage. The ABMI reference demonstrated the best performance in diagnosing obesity based on body composition analysis (boys=0.95;95%CI:0.94-0.95/girls=0.92;95%CI:0.92-0.93). The analysis of relative risk (RR) indicated that normal weight children who increased their BMI-GC during childhood by ≥0.67 and <0.86 were more likely to be overweight at 9.5-13.5 years [IOTFRR= 2.31; 95% CI: 1.82-2.93/MULT-RR=2.49; 95% CI: 2.00-3.09/WHO-RR=2.47; 95% CI: 1.96-3.12] compared to those who remained within their channel. Conclusion: For diagnosing obesity, the MULT reference performed better among the BMI references, while the ABMI reference showed the best performance overall, being the only one capable of detecting that girls had proportionally higher fat mass (FM) than boys for the same index values. Moreover, the canalization analysis indicated that an increase in BMI-GC ≥0.67 during childhood was associated with a significantly higher risk of overweight at 9.5-13.5 years. These results suggest that the MULT reference can be an excellent option to assess the nutritional status of children and adolescents.

Comparison of intergrowth-21st and Fenton curves for evaluation of premature newborns / Comparação das curvas de intergrowth-21st e de Fenton para avaliação de recém-nascidos prematuros

Abstract Objectives: to compare the intrauterine and postnatal growth of preterm infants according to the Intergrowth-21st and Fenton curves. Methods: study carried out in a maternity hospital, reference in high-risk pregnancy, with preterm infants born in 2018 who were hospitalized in the neonatal units of the institution. Preterm newborns weighed at least twice after birth were included in the sample and those that were syndromic, malformed or presented fluid retention were excluded. Proportions and means were compared using Pearson's chi-square and Student's t tests for paired samples, respectively. The McNemar test was used to compare categorical variables and the Kappa test to verify the degree of agreement between birth weight classifications obtained by the curves. Results: one hundred and fifty three infants with a median gestational age of 34.4 weeks were included. The incidences of the categories of nutritional status at birth did not differ between the curves. There was perfect agreement between the curves, except when newborns born under 33 weeks of gestational age were evaluated, in which case the agreement was substantial. About 21% of the babies classified as small for gestational age (SGA) by Intergrowth-21st were adequate for gestational age (AGA) according to Fenton and, on average, 20% of cases that had postnatal growth restriction (PNGR) according to Fenton standards were categorized as adequate weight by Intergrowth-21st. Postnatal weight classifications obtained by the evaluated curves had perfect agreement. Conclusions: the differences in theclassifications found between the charts reveal the importance of choosing the growth curve for monitoring preterm infants since behaviors based on their diagnoses can impact the life of this population.

Resumo Objetivos: comparar o crescimento intrauterino e pós-natal de prematuros segundo as curvas de Intergrowth-21st e Fenton. Métodos: estudo realizado em uma maternidade de referência em gestação de alto risco com prematuros nascidos em 2018 que ficaram internados nas unidades neonatais da instituição. Foram incluídos os pré-termos pesados em pelo menos dois momentos após o nascimento e excluídos aqueles sindrômicos, malformados ou com retenção hídrica. As proporções e médias foram comparadas a partir dos testes qui-quadrado de Pearson e t de student para amostras emparelhadas, respectivamente. Já o teste de McNemar foi utilizado para comparar as variáveis categóricas e teste Kappa para verificar o grau de concordância entre as classificações de peso ao nascer obtidos pelas curvas. Resultados: foram incluídos 153 lactentes com idade gestacional mediana de 34,4 semanas. As incidências das categorias de estado nutricional ao nascer não diferiram entre as curvas. Houve concordância perfeita entre as mesmas, exceto quando se avaliou os nascidos com menos de 33 semanas, onde a concordância foi substancial. Cerca de 21% dos bebês classificados como pequenos para a idade gestacional (PIG) por Intergrowth-21st foram adequados para idade gestacional (AIG) segundo Fenton e, em média, 20% dos casos que tiveram restrição de crescimento pós-natal (RCPN) de acordo aos padrões de Fenton foram categorizados com peso adequado por Intergrowth-21st. As classificações de peso pós-natal obtidas pelas curvas avaliadas tiveram concordância perfeita. Conclusões: as diferenças de classificação encontradas revelam a importância da escolha da curva de crescimento para monitorização de prematuros visto que, condutas baseadas em seus diagnósticos, podem impactar na vida dessa população.

Development of fetal growth charts in twins stratified by chorionicity and mode of conception: a retrospective cohort study in China / 中华医学杂志(英文版)

BACKGROUND@#Twin pregnancies continue to increase worldwide; however, the current clinical prenatal evaluation for the intrauterine growth of twins still relies on the growth standards of singletons. We attempted to establish a set of fetal biometric references for Chinese twin pregnancies, stratified by chorionicity and conception mode as spontaneously conceived monochorionic diamniotic (SC-MCDA), spontaneously conceived dichorionic diamniotic (SC-DCDA), and assisted reproductive technology dichorionic diamniotic (ART-DCDA) twins.@*METHODS@#From 2016 to 2019, the ultrasonographic fetal biometric measurements were longitudinally collected in pregnant women, including fetal weight, biparietal diameter, head circumference, abdominal circumference, femur length, and humerus length. The linear mixed models were used to test the difference of growth patterns between groups, and the growth curve of each biometric parameter was modeled by a generalized additive model for location scale and shape.@*RESULTS@#A total of 929 twin pregnant women and 2019 singleton pregnant women, met the inclusion criteria. Among twin pregnancies, 148 were SC-MCDA, 215 were SC-DCDA, and 566 were ART-DCDA twins. Overall, SC-DCDA twins grew faster than SC-MCDA twins, while slower than ART-DCDA twins (all P < 0.05), and all of the three groups showed significant differences comparing with singletons, especially during the third trimester. Hence, the customized fetal growth charts of each fetal biometric parameter were, respectively, constructed for SC-MCDA, SC-DCDA, and ART-DCDA twins.@*CONCLUSIONS@#The fetal biometric trajectories demonstrated characteristic patterns according to chorionicity and conception mode. To fill the gap, we modeled fetal biometric parameters for Chinese SC-MCDA, SC-DCDA, and ART-DCDA twin pregnancies, hoping to provide a reference for the further establishment of fetal growth reference values for Chinese twin fetuses.

Estudio del crecimiento de la estatura en una muestra de niños, niñas y adolescentes sanos de Córdoba, Argentina / Height growth study of healthy children and adolescents from Córdoba, Argentina

OBJETIVO: Describir el crecimiento en estatura, estimar la edad pico del estirón, la velocidad de crecimiento en dicho punto, la talla final adulta esperada y los patrones diferenciales en una muestra poblacional de ambos sexos. SUJETOS Y MÉTODO: Se realizó un estudio transversal recabando prospectivamente datos demográficos, clínicos y antropométricos en sujetos sanos de ambos sexos, entre 2015 y 2016. Se calcularon los percentiles para la estatura mediante el método LMS (sesgo, mediana y coeficiente de variabilidad) y luego se ajustaron dichos valores utilizando el modelo 1 de Preece-Baines. RESULTADOS: Se evaluaron 861 sujetos, edades 2 - 18 años, 377 varones y 484 mujeres. La edad estimada al pico del estirón (h0) fue de 13,6 años en los niños y de 11,0 años en las niñas, con una velocidad de crecimiento lineal en ese punto (V2) de 6,4 cm/año para ambos sexos. La estatura adulta media esperada (hj) se estimó en 173,7 cm en los chicos y en 160,0 cm en las chicas. CONCLUSIONES: El modelo 1 de Preece-Baines permitió estimar satisfactoriamente la edad pico del estirón, la velocidad de crecimiento en dicho punto y la talla final adulta esperada.

OBJECTIVE: Based on a sample of children and adolescents of both genders, our objective is to des cribe height growth, estimate the peak age at growth spurt, growth rate at this point, the final adult height expected, and differential patterns SUBJECTS AND METHOD: A cross-sectional study was conduc ted using demographic, clinical, and anthropometric data collected prospectively from children and adolescents of both sexes between 2015 and 2016. Height percentiles were calculated using the LMS (skewness, median, and coefficient of variation) method and then adjusted using the Preece-Baines model 1. RESULTS: We evaluated 861 participants (484 girls, 377 boys), aged between 2 and 18 years. The estimated peak age at growth spurt (he) was 13.6 years in boys and 11.0 years in girls, with a peak growth rate (V2) at this point of 6.4 cm/year for both sexes. The mean expected adult height (h1) was 173.7 cm in boys and 160.0 cm in girls. CONCLUSIONS: Preece-Baines model 1 provides satisfactory estimates for the peak age at growth spurt, peak growth rate at this point, and final expected adult height.

Recomendaciones para la evaluación del tamaño al nacer y del crecimiento posnatal de los recién nacidos prematuros / Recommendations for the assessment of birth size and postnatal growth of preterm newborns

Es innegable la necesidad de contar con curvas estándar de tamaño al nacer y crecimiento para evaluar y contribuir a orientar las acciones en la atención del neonato. Durante muchos años, se utilizaron las referencias de Lejarraga y Fustiñana, que fueron progresivamente reemplazadas por las de Fenton y Kim.Recientemente, el proyecto INTERGROWTH-21st construyó estándares de crecimiento prescriptivo para evaluar el tamaño al nacer desde las 33 semanas de edad gestacional, referencias para evaluar el tamaño al nacer desde las 24 a las 32,6 semanas de edad gestacional y curvas para el seguimiento longitudinal del crecimiento de recién nacidos pretérmino desde las 27 semanas de edad gestacional. Los Comités de Crecimiento y Desarrollo y de Estudios Feto-neonatales de la Sociedad Argentina de Pediatría, en conjunto con la Secretaría de Gobierno de Salud de la Nación, acordaron recomendar el reemplazo de las curvas de Fenton y Kim por las de INTERGROWTH-21st

It is unquestionable the need to have standards of size at birth and growth to evaluate and contribute to guide the actions in the care of the newborn. For many years the references of Lejarraga and Fustiñana were used, progressively replaced by those of Fenton and Kim. However, recently, the INTERGROWTH-21st project has developed prescriptive growth standards to evaluate the size at birth from 33 weeks of gestational age, references from 24 to 32.6 weeks of gestational age, and curves for postnatal growth from 27 weeks of gestational age onward. The Growth and Development and Neonatal Fetal Studies Committees of the Argentine Society of Pediatrics in conjunction with the Secretary of National Government of Health agreed to recommend the replacement of the Fenton and Kim curves with those of INTERGROWTH-21st.

Progresión de talla y peso en niños y niñas entre 6 y 12 años y su diferencia con las tablas de Ramos Galván 40 años después / Height and weight progression patterns in Mexican children aged between 6 and 12 years and differences with Ramos-Galvan growth charts 40 years later

Resumen Introducción: El peso y la talla de niños y adolescentes son un reflejo del estado de salud y desarrollo socioeconómico de la población. Objetivo: Evaluar las progresiones de talla y peso de niños y niñas mexicanos y compararlas con las tablas del doctor Ramos Galván a 40 años de distancia. Método: Encuesta transversal realizada en población del Programa Nacional de Activación Física Ponte al 100, que incluye niños y niñas de seis a 12 años. Resultados: Se evaluaron 43 670 niños y 44 103 niñas, que se estratificaron por sexo y edad. La progresión de talla entre los seis y 12 años fue de 21 cm en hombres y de 22 cm en mujeres; la progresión de peso fue de 9.86 y 10.05 kg, respectivamente para hombres y mujeres. La proporción de niños de seis y 12 años con sobrepeso fue de 11.2 y 9 % y con obesidad, de 14.7 y 15 %. La proporción de niñas de seis y 12 años con sobrepeso fue de 8.2 y 9.1 % y con obesidad, de 21.7 y 13.3 %, respectivamente. Al comparar los valores obtenidos con los de las tablas del doctor Ramos Galván para niños y niñas, el promedio de diferencia fue de 2 cm. Conclusiones: No se documentó un incremento secular de la talla ni del peso en los últimos 40 años.

Abstract Introduction: Children and adolescents weight and height are a reflection of the health status and socioeconomic development of a population. Objective: To evaluate height and weight progression patterns of Mexican children and compare them with Dr. Ramos-Galván growth charts 40 years later. Method: Cross-sectional survey conducted on the population of the National Physical Activation Program Ponte al 100, which includes boys and girls aged 6-12 years. Results: 43,670 boys and 44,103 girls were assessed, stratified by gender and age. The height progression pattern between six and 12 years was 21 cm in males and 22 cm in females, whereas the weight progression pattern was 9.86 and 10.05 kg, respectively, for males and females. The proportion of 6- and 12-year-old boys who were overweight was 11.2 and 9%, while 14.7 and 15% were obese. The proportion of 6- and 12-year-old girls who were overweight was 8.2 and 9.1%, whereas 21.7 and 13.3%, respectively, were obese. When the obtained values were compared with those of Dr. Ramos Galván growth charts for boys and girls, the average difference was 2 cm. Conclusions: No secular height or weight increase within the last 40 years was documented.

Local references for ultrasound-estimated fetal weight based on 2, 211 singleton pregnancies in the City of Curitiba, south of Brazil / Referências locais para o peso fetal estimado por ultrassom baseado em 2. 211 gestações únicas na cidade de Curitiba, Sul do Brasil

Abstract Objective To develop reference curves of estimated fetal weight for a local population in Curitiba, South of Brazil, and compare them with the curves established for other populations. Methods An observational, cross-sectional, retrospective study was conducted. A reference model for estimated fetal weight was developed using a local sample of 2,211 singleton pregnancies with low risk of growth disorders and well-defined gestational age. This model was compared graphically with the Hadlock and Intergrowth 21st curves. Results Reference curves for estimated fetal weight were developed for a local population. The coefficient of determination was R2 = 99.11%, indicating that 99.11% of the fetal weight variations were explained by the model. Compared with Hadlock curves, the 50th, 90th, and 97th percentiles in this model were lower, whereas the 10th percentile nearly overlapped, and the 3rd percentile was slightly higher in the proposed model. The percentiles were higher in the proposed model compared with the Intergrowth 21st curves, particularly for the 3rd, 10th, and 50th percentiles. Conclusion We provide a local reference curve for estimated fetal weight. The proposed model was different from other models, and these differences might be due to the use of different populations for model construction.

Resumo Objetivo Desenvolver curvas de referência para o peso fetal estimado em uma população de Curitiba, Sul do Brasil, e compará-las com curvas estabelecidas para outras populações. Métodos Foi realizado um estudo observacional, transversal e retrospectivo. Um modelo de referência para o peso fetal estimado foi desenvolvido usando uma amostra local de 2.211 gestações únicas de baixo risco de distúrbios do crescimento e idade gestacional bem definida. Este modelo foi comparado graficamente com as curvas de Hadlock e Intergrowth 21st. Resultados As curvas de referência para o peso fetal estimado foram desenvolvidas para uma população local. O coeficiente de determinação foi de R2 = 99,11%, indicando que 99,11% das variações do peso fetal foram explicadas pelo modelo. Em comparação com as curvas de Hadlock, os percentis 50, 90, e 97 neste modelo foram inferiores, enquanto o percentil 10 quase se sobrepôs, e o percentil 3 foi ligeiramente superior no modelo proposto. Os percentis foram maiores no modelo proposto em comparação com as curvas do Intergrowth 21st, particularmente para os percentis 3, 10, e 50. Conclusão Fornecemos uma curva de referência local para o peso fetal estimado. O modelo proposto foi diferente de outros modelos, e essas diferenças podem ser devido ao uso de diferentes populações para a construção do modelo.

Referencias de peso, estatura e índice de masa corporal para niñas y niños ecuatorianos de 5 a 19 años de edad / Growth references for weight, height, and body mass index for Ecuadorian children and adolescents aged 5-19 years

Introducción. La evaluación del crecimiento durante la infancia y la adolescencia es un componente fundamental de la atención de salud en todos sus niveles, pues es parte del diagnóstico nutricional y permite la detección oportuna de patologías relacionadas. Ecuador, al no disponer de referencias nacionales de crecimiento, ha adoptado los estándares internacionales de la Organización Mundial de la Salud. El objetivo de este estudio fue construir referencias nacionales de peso, estatura e índice de masa corporal para niños, niñas y adolescentes.Métodos. Se investigaron escolares y adolescentes ecuatorianos entre 5 y 19 años de edad durante 1999 y 2012. Los centilos 3, 10, 25, 50, 75, 90 y 97 de peso, talla e índice de masa corporal fueron estimados por el método LMS para datos transversales, que utiliza la transformación Box-Cox para normalizar la distribución de los datos a cada edad.Resultados. Participaron 5934 sujetos sanos (2788 niños y 3146 niñas). Los niños pesaban más y eran más altos que las niñas. En todos los casos, los valores mostraron un aumento creciente conforme la edad avanzaba. A los 18 años, las diferencias entre sexos promediaron 8 kg y 12,5 cm.Conclusión. Las tablas y curvas producto de este estudio constituyen la primera referencia descriptiva del crecimiento de niños ecuatorianos de 5-19 años. Son un importante instrumento de evaluación nutricional. Su implementación en la atención primaria de salud permitirá complementar el diagnóstico nutricional que, tradicionalmente, se realiza sobre la base de los estándares internacionales de la Organización Mundial de la Salud.

Introduction. The assessment of growth during childhood and adolescence is a critical component of health care at all levels, but it is also part of nutritional status diagnosis and the timely detection of related conditions. Ecuador lacks national growth references, so it has decided to adopt the international standards proposed by the World Health Organization. The objective of this study was to develop national references for weight, height, and body mass index for children and adolescents.Methods. Ecuadorian schoolchildren and adolescents aged 5-19 years were studied between 1999 and 2012. The LMS method for cross-sectional data, which uses the Box-Cox transformation to normalize data distribution at each age, was applied to estimate the 3rd, 10th, 25th, 50th, 75th, 90th, and 97th centiles for weight, height, and body mass index.Results. A total of 5934 healthy subjects (2788 boys and 3146 girls) participated. Boys were heavier and taller than girls. In all cases, values increased with age. At 18 years old, the differences between sexes averaged 8 kg and 12.5 cm.Conclusion. The tables and curves obtained with this study are the first descriptive growth references for Ecuadorian children and adolescents aged 5-19 years. They are relevant for nutritional assessment. Their use at the primary level of care will aid in nutritional status diagnosis, which has traditionally been done based on the World Health Organization's international standards.

Ajuste de curvas de crecimiento poblacional aplicadas a la COVID-19 en Cuba / Adjustment of population growth curve applied to COVID-19 in Cuba

Introducción: Cuba ha sido afectada por la COVID-19. Todas las provincias del país han presentado casos confirmados de la enfermedad. Se han llevado a cabo medidas por parte del gobierno y el sistema de salud, para contrarrestar el contagio de persona a persona. Es de gran ayuda contar con estimaciones de casos confirmados para las decisiones. Objetivos: Obtener predicciones para los picos de casos confirmados y cantidad total de estos para algunas provincias de Cuba y para todo el país. Material y Métodos: Estudio de tipo predictivo de curvas de crecimiento poblacional. Se analizan los datos correspondientes a los primeros 52 días de afectación de la enfermedad en el país para estimar los modelos y aplicar el método de los mínimos cuadrados para modelos no lineales con respecto a los parámetros. Se utilizan el coeficiente de determinación ajustado, el criterio de información de Akaike y el error estándar de los residuos para medir la bondad del ajuste de los modelos. Se estudian las provincias del país que presentan una tasa de infectados por cien mil habitantes mayor que 14,71 y el país en su conjunto. Resultados: La bondad de ajuste de los modelos utilizados en las localidades estudiadas y en el país es alta, lo cual permite su confiabilidad para los pronósticos efectuados. Conclusiones: Las predicciones plantean que las cinco localidades analizadas presentan su pico de contagio en abril al igual que Cuba (AU)

Introduction: Cuba and all its provinces have been affected by COVID-19 disease. The government and the health system have taken measures to avoid contagion from person to person. To take these measures it is important to have estimates of the rate of infection. Objectives: To obtain predictions for the peak of infected cases and the total number for some Cuban provinces and the whole country. Material and Methods: Predictive study of population growth curves. Data from the first 52 days of the disease in the country are processed to estimate the models and to apply the method of least squares estimation of nonlinear parameters. The adjusted coefficient of determination, the Akaike information criterion and the standard error of the residuals are used to measure the goodness of fit of the models. The provinces that present a rate of infection per 100,000 inhabitants greater than 14,71 and the country as a whole are studied. Results: The goodness of fit of the models used in the provinces studied and the country is high, which allows them to be reliable for predictions. Conclusions: The predictions suggest that the five provinces analyzed and Cuba show their peak of contagion in April (AU)

Comparison of adequacy of birth weight for gestational age according to different intrauterine growth curves / Comparação da adequação do peso ao nascer para idade gestacional segundo diferentes curvas de crescimento intrauterino

Abstract Objectives: to compare the assessment of the adequacy of birth weight for gestational age according to different intrauterine growth curves. Methods: across-sectional study, which analyzed gestational and neonatal information from 344 mother-newborn binomials. Birth weight data were analyzed using the International Fetal and New Born Growth Consortium for the 21st Century (INTERGROWTH-21st) and compared with the growth curves proposed by Alexander et al. and Fenton & Kim. Newborns were classified as small for gestational age (SGA), suitablefor gestational age (SUGA) or large for gestational age (LGA). Results: among the newborns, 51.2% were male, and 93.0% were born at term. Higher prevalence of SUGA and LGA and lower SGA was found by the INTERGROWTH-21st curves when compared to the references of Fenton & Kim and Alexander et al. Moderate agreement was observed in detecting birth weight by different growth curves. Conclusions: there was a lower detection of SGA infants and a higher screening, especially of LGA infants, in the INTERGROWTH-21st evaluation, when compared to the growth curves of Fenton & Kim and Alexander et al.

Resumo Objetivos: comparar a avaliação da adequação do peso ao nascer para idade gestacional segundo diferentes curvas de crescimento intrauterino. Métodos: estudo transversal, onde foram analisadas informações gestacionais e neonatais de 344 binômios mães-recém-nascidos. Os dados de peso ao nascer foram analisados utilizando-se a International Fetal and New Born Growth Consortium for the 21st Century (INTERGROWTH-21st) e comparados com as curvas de crescimento propostas por Alexander et al. e Fenton & Kim. Os recém-nascidos foram classificados em pequenos para idade gestacional (PIG), adequados para idade gestacional (AIG) ou grandes para idade gestacional (GIG). Resultados: dentre os recém-nascidos, 51,2% eram do sexo masculino, sendo que 93,0% nasceram a termo. Maior prevalência de AIG e GIG e menor de PIG foi constatada pelas curvas INTERGROWTH-21st, quando comparadas às referências de Fenton & Kim e Alexander et al. Foi observada concordância moderada na detecção do peso ao nascer pelas diferentes curvas de crescimento. Conclusões: verificou-se menor detecção de recém-nascidos PIG e maior rastreio, principalmente, de recém-nascidos GIG na avaliação pela INTERGROWTH-21st, quando comparada às curvas de crescimento de Fenton & Kim e Alexander et al.

Body composition indices in Brazilian adults: age-specific and sex-specific percentile curves

ABSTRACT Objective To establish percentile curves for measures and indices of body composition by age and sex and compare them with data from other ethnic groups. Subjects and methods Cross-sectional, population-based study with adults aged 20-59 years (n = 689). Percentile curves adjusted by a third degree polynomial function were constructed for skeletal mass index (SMI), fat mass index, body fat, and load-capacity metabolic indices (LCMI) based on dual-energy X-ray absorptiometry (DXA). Results SMIweight and SMIBMI showed decline from the third decade of life in both sexes, whereas SMIheight was not able to identify lean mass loss over the ages studied. There was a slight drop at the end of the fifth decade (50-59 years) in men. Among Americans and Chinese, the 50th percentile curve of SMIheight showed an earlier decline. The estimates of adiposity and LCMI curves peaked between 40-49 years and Americans and Chinese maintained an upward curve throughout adulthood. Conclusion The data and curves showed that the SMI adjusted for BMI and body weight were more adequate in detecting the decline of lean mass in adults due to aging. In contrast, SMIheight had a positive correlation with age and its curve increased throughout the evaluated age groups. The results contribute to the evaluation to the nutritional status of adults and to the prevention and treatment of outcomes related to adiposity and deficit lean mass.

Association of Bisphenol A and Its Substitutes, Bisphenol F and Bisphenol S, with Obesity in United States Children and Adolescents

BACKGROUND: Bisphenol F (BPF) and bisphenol S (BPS) are increasingly used as substitutes for bisphenol A (BPA), an environmental obesogen. However, health effects of BPF and BPS remain unclear. In this study, we evaluated the associations of BPA, BPF, and BPS with obesity in children and adolescents. METHODS: We used data from the U.S. National Health and Nutrition Examination Survey 2013 to 2014, a nationally representative study. We included 745 participants aged 6 to 17 years old. General obesity was defined based on the 2000 Centers for Disease Control and Prevention body mass index-for-age growth charts for the United States. Abdominal obesity was defined as waist-to-height ratio ≥0.5. RESULTS: After adjustment for demographic, socioeconomic and lifestyle factors, and urinary creatinine levels, the odds ratio of general obesity comparing the highest with lowest quartile of urinary bisphenol levels was 1.74 (95% confidence interval [CI], 0.92 to 3.31) for BPA, 1.54 (95% CI, 1.02 to 2.32) for BPF, and 1.36 (95% CI, 0.53 to 3.51) for BPS. Moreover, the associations were stronger in boys than in girls for BPA and BPF. Similar results were observed for abdominal obesity. CONCLUSION: This study for the first time showed that exposure to BPF, a commonly used substitute for BPA, was positively associated with higher risk of obesity in children and adolescents. The association of BPA and BPF with general and abdominal obesity was primarily observed in boys, suggesting a possible sex difference. Further investigations on the underlying mechanisms are needed.

Preterm newborn's postnatal growth patterns: how to evaluate them / Padrões de crescimento pós-natal do recém-nascido prematuro: como avaliar

Abstract Objectives: There are several factors that influence the postnatal growth of preterm infants. It is crucial to define how to evaluate the growth rate of each preterm child and its individual trajectory, the type of growth curve, either with parameters of prescriptive curves for healthy preterm infants with no morbidities or, in the case of preterm infants and their "bundle of vulnerabilities", growth curves that may represent how they are actually growing, with the aim of directing appropriate nutritional care to each gestational age range. Data sources: The main studies with growth curves for growth monitoring and the appropriate nutritional adjustments that prioritized the individual trajectory of postnatal growth rate were reviewed. PubMed and Google Scholar were searched. Data synthesis: The use of longitudinal neonatal data with different gestational ages and considering high and medium-risk pregnancies will probably be essential to evaluate the optimal growth pattern. Conclusions: Prioritizing and knowing the individual growth trajectory of each preterm child is an alternative for preterm infants with less than 33 weeks of gestational age. For larger preterm infants born at gestational age >33 weeks, the Intergrowth 21st curves are adequate.

Resumo Objetivos: Inúmeros são os fatores que influenciam o crescimento pós-natal de prematuros. É fundamental a definição de como avaliar velocidade de crescimento de cada criança nascida prematura e sua trajetória individual, o tipo de curva de crescimento, seja com parâmetros de curvas prescritivas para prematuros saudáveis e sem morbidades ou no caso de um prematuro e seu "pacote de vulnerabilidades", curvas de crescimento que possam representar como eles realmente crescem, com a finalidade de direcionar o cuidado nutricional apropriado a cada faixa de idade gestacional. Fonte de dados: Foram revisados os principais estudos com curvas de crescimento na monitoração do crescimento e nos ajustes nutricionais apropriados que priorizaram a trajetória individual da velocidade de crescimento pós-natal. Foram consultados PubMed e Google Scholar. Síntese dos dados: O uso de dados neonatais longitudinais com diferentes idades gestacionais e considerando gestações de alto e médio risco provavelmente será fundamental para avaliar o padrão ótimo de crescimento. Conclusões: Priorizar e conhecer a trajetória individual de crescimento de cada criança nascida prematura é opção para prematuros com menos de 33 semanas. Para prematuros maiores, nascidos com idade gestacional acima de 33 semanas, as curvas Intergrowth 21 st são adequadas.

Dietary and Lifestyle Factors Associated with Weight Status among Korean Adolescents from Multicultural Families: Using Data from the 2017–2018 Korea Youth Risk Behavior Surveys / 대한지역사회영양학회지

OBJECTIVES: This study investigated dietary and lifestyle factors associated with the weight status among Korean adolescents in multicultural families.METHODS: This cross-sectional study analyzed 1,751 multicultural families' adolescents who participated in the 2017–2018 Korea Youth Risk Behavior Surveys. Information on dietary and lifestyle factors was self-reported using a web-based questionnaire and this information included breakfast and foods consumption, perceived health status, alcohol drinking, smoking, physical activity, and weight control efforts. Body mass index (BMI) was calculated based on the self-reported height and body weight (kg/m²). Weight status was assessed according to the 2017 Korean National Growth Chart: underweight (weight-for-age <5(th) percentiles), overweight (85(th)≤ BMI-for-age <95(th) percentiles), and obese (BMI-for-age ≥95(th) percentiles). Multiple logistic regression analysis was performed to examine the dietary and lifestyle factors associated with weight status after adjustment for covariates.RESULTS: Among Korean adolescents from multicultural families, the prevalence of overweight/obesity was 20.9%, whereas about 7% of adolescents were underweight. The weight status did not show differences according to gender, school level, area of residence, and household income. Compared to adolescents who did not have breakfast during the previous week, those who had breakfast 3–4 days/week and ≥5 days/week had a 42% (p=0.021) and a 37% (p=0.009) lower prevalence of overweight/obesity, respectively. The adolescents who frequently consumed carbonated soft drinks (≥5 times/week) showed an odds ratio (OR) of 1.69 (95% CI=1.01–2.83) for overweight/obesity relative to those adolescents who did not consume carbonated soft drinks. The OR of being underweight for adolescents who ate fast food ≥3 times/week was 1.97 (95% CI=1.04–3.71) compared to those adolescents who had not eaten fast food during the previous week.CONCLUSIONS: Dietary and lifestyle factors were associated with overweight/obesity as well as underweight among Korean adolescents in multicultural families. Our findings could be used to design and provide nutrition interventions for this specific population.

Association between Body Mass Index and Hepatitis B antibody seropositivity in children / 소아과

BACKGROUND: The seropositivity rate of hepatitis B surface antigen (anti-HBs) antibodies is known to be ≥95% after hepatitis B virus vaccination during infancy. However, a low level or absence of anti-HBs in healthy children is discovered in many cases. Recent studies in adults reported that a reduced anti-HBs production rate is related to obesity.PURPOSE: To investigate whether body mass index (BMI) affects anti-HBs levels in healthy children following 3 serial dose vaccinations in infancy.METHODS: We recruited 1,200 healthy volunteers aged 3, 5, 7, or 10 years from 4-day care centers and 4 elementary schools. All subjects completed a questionnaire including body weight, height, and vaccine type received. Levels of serum hepatitis B surface antigen (HBsAg) and anti-HBs in all subjects were analyzed using electrochemiluminescence immunoassay. The standardized scores (z score) for each sex and age were obtained using the lambda-mu-sigma method in the 2017 Korean National Growth Charts for children and adolescents.RESULTS: Our subjects (n=1,200) comprised 750 males (62.5%) and 450 females (37.5%). The overall anti-HBs seropositivity rate was 57.9% (695 of 1,200). We identified significant differences in mean BMI values between seronegative and seropositive groups (17.45 vs. 16.62, respectively; P<0.001). The anti-HBs titer was significantly decreased as the BMI z score increased adjusting for age and sex (B=-15.725; standard error=5.494; P=0.004). The probability of anti-HBs seropositivity based on BMI z score was decreased to an OR of 0.820 after the control for confounding variables (95% confidence interval, 0.728–0.923; P=0.001).CONCLUSION: There was a significant association between anti-HBs titer and BMI z score after adjustment for age and sex. Our results indicate that BMI is a potential factor affecting anti-HBs titer in healthy children.

Secular change in waist circumference and waist-height ratio and optimal cutoff of waist-height ratio for abdominal obesity among Korean children and adolescents over 10 years / 소아과

PURPOSE: This study aimed to evaluate the time trends of waist circumference (WC) and waist-height ratio (WHR), and to present WC and WHR distributions with optimal WHR cutoff for abdominal obesity in Korean children and adolescents. METHODS: We performed a retrospective cross-sectional analysis of data from 13,257 children and adolescents (6,987 boys and 6,270 girls) aged 6–18 years who were included in the third to sixth Korea National Health and Nutrition Examination Survey (KNHANES, 2005–2015). Linear regression analyses were used to identify secular changes in WC and WHR by age, sex, and KNHANES waves. A receiver operating characteristic curve analysis was used to determine the optimal WHR cutoff values for abdominal obesity and cardiometabolic risk factors. RESULTS: The mean WC and WHR distributions from 2005 to 2015 showed no significant secular changes between the KNHANES 4 waves (P for trend ≥0.05 in all ages and both sexes). The mean WCs in the present study were lower than those in the 2007 Korean National Growth Charts. The mean WHR at ages <13 years was statistically higher in the boys than in the girls, but did not significantly differ between the sexes among those aged 13 to 18 years. The optimal WHR cutoff for abdominal obesity was 0.48 (area under the curve, 0.985; 95% confidence interval, 0.985–0.985) in the 13- to 18-year-old adolescents. CONCLUSION: WC and WHR showed no secular changes over 10 years. The optimal WHR cutoff for abdominal obesity of 0.48 is useful for diagnosing and managing obesity and thus preventing obesity-related cardiometabolic complications in 13- to 18-year-old Korean adolescents.

Induction and growth curve of calli from leaf and nodal explants of genipap / Indução e curva de crescimento de calos obtidos de explantes foliares e nodais de jenipapeiro

The aim of this study was to determine the effect of the auxin 2,4-D (2,4-dichlorophenoxyacetic) in calli formation from leaf and nodal segments of genipap and to characterize its growth curve. Explants obtained from shoots previously established from in vitro seedlings were used for calli induction. The experimental design was completely randomized in a 3x5x2 factorial with three accessions (NB, SA, SAL), five concentrations of 2,4-D (0.0; 2.0; 4.0, 6.0 or 8.0 mg L-1) and two times of measurement for calli fresh weight (30 and 60 days). There was callus formation in all treatments tested. It was observed that the best response for callus induction from leaf segments was with 2.0 mg L-1 of 2,4-D. For the nodal segment, the response among the accessions was different due to 2,4-D concentrations. The growth curve was plotted according to the fresh weight of callus obtained at intervals of 10 days up to 60 days. Through the established growth curve, the nodal-derived calli from accession SA should be transferred to a new medium, after 40 days of culture.

O objetivo desse trabalho foi determinar o efeito da auxina 2,4-D (ácido diclorofenoxiacético) na calogênese de segmentos foliar e nodal de jenipapeiro e caracterizar sua curva de crescimento. Explantes obtidos de brotações pré-estabelecidas a partir de plântulas in vitro foram utilizados na indução de calos. O delineamento experimental utilizado foi o inteiramente casualizado em esquema fatorial 3x5x2, com três acessos (NB, SA e SAL), cinco concentrações de 2,4-D (0,0; 2,0; 4,0; 6,0 ou 8,0 mg L-1) e dois tempos de avaliação (30 e 60 dias) da massa fresca de calos. Houve formação de calos em todos os tratamentos testados. Observou-se que a melhor resposta de indução ocorreu na concentração de 2,0 mg L-1 para calos oriundos de segmentos foliares. Para o segmento nodal a resposta entre os acessos foi diferenciada em função das concentrações de 2,4-D. A curva de crescimento foi plotada a partir da massa fresca dos calos obtida em intervalos de 10 dias até os 60 dias. Através da curva de crescimento estabelecida, os calos derivados de segmentos nodais do acesso SA devem ser transferidos para um novo meio de cultura, 40 dias após à inoculação.

Crecimiento físico en jóvenes futbolistas chilenos: propuesta de percentiles por edad cronológica y biológica / Physical growth in young Chilean football players: Proposal of percentiles based on chronological and biological age

Objetivos. a) Comparar el crecimiento físico con la referencia americana de los Centros para el Control y la Prevención de Enfermedades (Centers for Disease Control and Prevention, CDC) 2012; b) analizar el crecimiento físico por edad cronológica y biológica; c) proponer curvas de crecimiento físico por edad cronológica y biológica. Metodología. Se efectuó una investigación descriptiva (transversal) en jóvenes futbolistas de Chile sobre peso, estatura de pie y estatura sentada. Se compararon con las referencias del CDC-2012. Se desarrollaron percentiles por medio del método LMS. Resultados. Se estudió a 642 jóvenes futbolistas chilenos de 13,0-18,9 años. Su peso corporal fue inferior al CDC desde los 13,0 hasta los 18,9 años (p < 0,05), mientras que, en la estatura, no hubo diferencias significativas a edades iniciales (13,013,9 y 14,0-14,9 años). Las diferencias empezaron a aparecer desde los 15,0 hasta los 18,9 años (p < 0,05). Por edad cronológica, el peso explicó 31%; la estatura de pie, 16% y estatura sentada, 0,09%, mientras que, por edad biológica, el peso explicó 51%; la estatura de pie, 40% y estatura sentada, 54%. Se desarrollaron percentiles por edad cronológica y biológica. Conclusión. Estos jóvenes difieren en sus patrones de crecimiento físico en relación con el CDC-2012. Su evaluación refleja mejores porcentajes de explicación por edad biológica que por edad cronológica. Los percentiles propuestos pueden ser una alternativa para seguir la trayectoria de crecimiento físico de jóvenes futbolistas en contextos deportivos a corto, mediano y largo plazo.

Objectives. a) To compare physical growth to the 2012 American standard from the Centers for Disease Control and Prevention (CDC); b) to analyze physical growth by chronological and biological age; c) to propose physical growth charts based on chronological and biological age. Methodology. A descriptive (cross-sectional) study was conducted in young Chilean football players based on weight, standing height, and sitting height. These were compared to the CDC-2012 standard. Percentiles were developed using the LMS method. Results. A total of 642 young Chilean football players aged 13.0-18.9 years were studied. Their body weight was lower than that of the CDC standard from 13.0 to 18.9 years old (p < 0.05), whereas their height showed no significant differences in the initial age categories (13.013.9 and 14.0-14.9 years). Differences started to be observed as of 15.0 years old up to 18.9 years old (p < 0.05). In relation to chronological age, weight explained 31%; standing height, 16%; and sitting height, 0.09%, whereas in relation to biological age, weight explained 51%; standing height, 40%; and sitting height, 54%. Percentiles were developed based on chronological and biological age. Conclusion. These youth showed different physical growth patterns compared to the CDC-2012 standard. Their assessment reflects better explanatory percentages for biological age than for chronological age. The proposed percentiles may be an alternative to keep track of the physical growth patterns of young football players in sports settings in the short, medium, and long term.