Decline in pubertal timing and its relationship with excess weight. A study of the secular trend in age at menarche in girls from La Plata district (Buenos Aires, Argentina).

OBJECTIVE: To provide information on the secular trend in age at menarche (AgM) in Argentinean girls in relation to excess weight (EW) and body adiposity. METHODS: Two cohorts (C) (C1, 2005-2007 and C2, 2015-2019) of children aged 8-14 years from La Plata district were studied using identical methodological criteria. Each participating child was asked about menarche (M) status: M presence (MP) or absence (MA). The AgM was estimated using the status quo method and logistic regression analysis. Body weight, height, and tricipital and subscapular skinfolds were collected to estimate EW (overweight + obesity) according to WHO criteria, and body adiposity (sum of skinfolds, SSK = [tricipital + subscapular]). The prevalence of EW by C was estimated and compared using the Chi-square test. The MP probability in relation to age, C, and EW was analyzed by applying logistic regression. Parents completed a questionnaire to assess family socioeconomic conditions. Data were compared using the Chi-square test. RESULTS: Differences in MP prevalence between C were significant (C1: 21.1% vs. C2: 28.7%). Median AgM was 12.81 years in C1 and 12.22 in C2. The prevalence of EW was higher in C2 (35.3%) than in C1 (24.6%). The probability of MP was higher in C2 than in C1 and children with EW. Both BMI and SSK showed inter-cohort increases. Socioeconomic conditions were substantially deteriorated between C. CONCLUSION: In an obesogenic context marked by the significant increase in body adiposity and EW, M prevalence exhibited a positive secular trend and AgM reduced by nearly seven months between the cohorts studied.

Comparison of frame index reference percentiles in Argentine and European boys and girls.

INTRODUCTION: The frame index (FI), based on measurements of elbow breadth and height, is the body frame size parameter most frequently used in child and adolescent populations to assess skeletal robustness. In 2018, the first FI reference percentiles were elaborated with data of boys and girls aged 0-18 years from different European populations. In Argentina, the FI reference values were published in 2022. OBJECTIVE: The present study aims to compare the Argentine (AR) and European (EU) FI reference percentiles to evaluate possible variation in bone robustness between populations. METHODS: The values of the 3rd, 50th and 97th percentiles of the AR and EU FI references for boys and girls aged 4-14 years were compared using the Wilcoxon test (p < .05). Percentage differences between means (PDM) were calculated to analyze the magnitude of the differences between both references. The R 3.2.0 program was used to plot the percentile curves. RESULTS: The FI reference values were lower in AR than in EU in both the 3rd and the 50th percentiles, regardless of sex and age. Conversely, the AR reference values of the 97th percentile were higher than the EU values at most ages. CONCLUSIONS: The comparison of the AR and EU FI references showed similar age and sex growth patterns. However, differences in percentile values between populations were observed, highlighting the importance of having local references for the evaluation of skeletal robustness.

Referencias de índice de masa corporal. Precisión diagnóstica con área grasa braquial en escolares argentinos / Body mass index references. Diagnostic accuracy with the upper-arm fat area in Argentine schoolchildren

El índice de masa corporal (IMC) es una eficaz herramienta para detectar la sobrecarga ponderal en niños y adolescentes, asociado a la adiposidad corporal. Objetivo. Analizar la concordancia, sensibilidad y especificidad de tres referencias internacionales de IMC/edad (OMS, IOTF y CDC) para diagnosticar el exceso ponderal y conocer su precisión diagnóstica para identificar el exceso de adiposidad con relación al área grasa braquial (AGB) en población infanto juvenil de Argentina. Materiales y métodos. Se realizó un estudio multicéntrico, descriptivo-comparativo y transversal entre 2003 y 2008, en 22.658 niños y adolescentes argentinos de 4 a 13 años de edad. A partir del peso, talla, circunferencia del brazo y pliegue tricipital, se calcularon IMC y AGB. Se analizó la concordancia, sensibilidad y especificidad de referencias de IMC/edad (OMS, CDC, IOTF) y la precisión diagnóstica (curvas ROC) para identificar exceso de adiposidad, a partir del AGB, así como el punto de corte óptimo (PCO). Resultados. Las tres referencias tuvieron buena concordancia. La mayor sensibilidad correspondió a OMS y la mayor especificidad a IOTF. El área bajo la curva (ABC) fue mayor en Z-IMC/IOTF en varones y en Z-IMC/OMS en mujeres. Los PCO mostraron discrepancias, siendo mayores con OMS. Conclusión. Las tres referencias muestran similar precisión diagnóstica para detectar alta reserva calórica, con puntos de corte óptimo para las puntuaciones Z-IMC menores a 2 Z scores. Esto resulta relevante para la identificación de exceso de adiposidad en poblaciones, en relación con la implementación de políticas públicas de prevención de enfermedades crónicas no transmisibles(AU)

The body mass index (BMI) is an effective tool to detect weight overload in children and adolescents, associated with body adiposity. Objective. To analyze the concordance, sensitivity and specificity of three international BMI/age references (WHO, IOTF and CDC) to diagnose excess weight and to know their diagnostic accuracy to identify excess adiposity in relation to the brachial fat area (BFA) in Argentine child-youth population. Materials and methods. A multicenter, descriptive- comparative and cross-sectional study was carried out between 2003 and 2008 in 22.658 Argentine children and adolescents between aged 4 to 13 years. From the weight, height, arm circumference and tricipital fold, BMI and BFA were calculated. The concordance, sensitivity, and specificity of BMI / age references (WHO, IOTF, CDC,) were analyzed and the diagnostic precision (ROC curves) to identify excess adiposity, from the BFA, as well as the optimal cut-off point (OCP). Results. The three references had good agreement, the highest sensitivity corresponded to WHO and the highest specificity to IOTF. The area under the curve (AUC) was greater in Z-BMI/IOTF in men and in Z-BMI/WHO in women. The OCPs showed discrepancies, being higher with WHO. Conclusion. The three references show similar diagnostic accuracy to detect high caloric reserve, but with cut-off points for Z-BMI scores less than 2 Z scores. This is relevant for the identification of excess adiposity in populations in relation to the implementation of public policies for the prevention of chronic non-communicable diseases(AU)

Body composition in relation to nutritional status and socio-environmental conditions in schoolchildren living in the urban periphery of La Plata, Argentina

The aim of this study was to evaluate body composition in relation to nutritional status and socio-environmental conditions of residence in schoolchildren living in the urban periphery of La Plata, Argentina. Weight, height, arm circumference and tricipital and subscapular skinfolds were measured in 3,284 schoolchildren aged 4-12 years in the period 2014-2017. The National Health and Nutrition Examination Survey (NHANES) III reference was used to assess nutritional status, identifying the following categories: normal, underweight, stunting, wasting, overweight and obesity. Body composition was evaluated based on upper arm muscle area (UMA) and upper arm fat area (UFA). Deficit and excess UMA and UFA were also calculated. Central fat distribution was determined with the subscapular-tricipital index. Socio-environmental characteristics were surveyed using a structured questionnaire. The prevalence of nutritional status and body composition indicators were compared by sex using Chi square test. Socio-environmental data were analyzed using categorical Principal Component Analysis, discriminating into more favorable and unfavorable conditions. Nutritional status results were as follows: normal, 64.5%; stunting, 3.4%; underweight, 0.0%; wasting, 0.1%; overweight, 15.6% and obesity 16.4%. The nutritional status of children worsened as the socio-environmental condition of their families became more precarious. Long-term socio-environmental stress manifested as decreased muscle tissue in normal, stunted, overweight and obese children. The current results evidence the strong impact of poverty on child growth and development and at the same time enforce the need for continuous monitoring of children with hidden malnutrition(AU)

El objetivo del trabajo fue analizar la composición corporal en relación al estado nutricional y las condiciones socio-ambientales de niños residentes en la periferia urbana de La Plata, Argentina. Sobre 3284 escolares de 4 a 12 años se evaluaron peso, talla, perímetro braquial y pliegues tricipital y subescapular, durante los años 2014-2017. Se determinaron, utilizando la referencia NHANES III, las categorías de estado nutricional Normal; Bajo Peso/Edad; Baja Talla/Edad; Bajo IMC/Edad; Sobrepeso y Obesidad, y para composición corporal, se calcularon las áreas muscular y grasa (UMA y UFA) y se estimaron los déficits y excesos de tejido muscular y graso. La adiposidad centralizada fue estimada con el índice subescapular-tricipital. Las características socio-ambientales se evaluaron mediante encuesta estructurada. Las prevalencias del estado nutricional y de los indicadores de composición corporal fueron estimados y comparados por sexos, mediante pruebas de Chi2. Los datos socio-ambientales se analizaron empleando Análisis de Componentes Principales categóricos y se discriminaron dos grupos: con condiciones más favorables y con condiciones desfavorables. Los resultados indicaron: 64.5% Normal, 3.4% Baja Talla/Edad, 0.0% Bajo Peso/Edad; 0.1% Bajo IMC/Edad; 15.6% Sobrepeso; 16.4% Obesidad. El estado nutricional de los niños empeoró cuando la calidad socio-ambiental de sus familias se hizo más precaria. Debido al estrés socio-ambiental continuo, los niños tuvieron disminución del tejido muscular, incluyendo aquellos con estado nutricional Normal, Baja Talla/Edad, Sobrepeso y Obesidad. Los resultados alcanzados evidencian la impronta que deja la pobreza e impone urgentemente el monitoreo continuo de niños "con desnutrición oculta"(AU)

High Blood Pressure in Children and Adolescents from Urban Peripheral Areas of La Plata, Argentina / Presión arterial elevada en niños y adolescentes residentes en áreas periurbanas de la ciudad de La Plata, Argentina

ABSTRACT Objective: The aim of the present study was to estimate the prevalence of high blood pressure in schoolchildren aged 4-14 years from urban peripheral areas of the city of La Plata, and analyze variations in high blood pressure prevalence by sex, age, excess weight and family socioeconomic status. Materials and methods: Systolic and diastolic blood pressure, body weight and height were measured in 3,312 schoolchildren of both sexes. The prevalence of high blood pressure (HBP), overweight and obesity was calculated. Socioeconomic information was obtained through a semi-structured survey and processed by categorical principal-component analysis. The prevalence of HBP was compared with sex, age and nutritional status (chi square test) and family socioeconomic status (generalized linear model) (p< 0,05). Results: The results showed that the prevalence of HBP was 20.5% and that it varied by age, nutritional status and family socioeconomic status. Sexual differences were observed only in HBP obese schoolchildren. Conclusions: Children and adolescents living in urban peripheral areas of the city of La Plata, Argentina, presented higher HBP prevalence. While HBP prevalence was higher among overweight/obese children, those aged >8 years and those of more favorable family socioeconomic status, sex did not affect HBP development. However, when HBP was analyzed associated with nutritional status, obese boys were more likely to have HBP than girls.

RESUMEN Objetivo: Estimar la prevalencia de la presión arterial elevada (PAE) en escolares de 4 a 14 años de edad residentes en áreas periféricas de la ciudad de La Plata y analizar variaciones de acuerdo al sexo, la edad, el exceso ponderal y el nivel socioeconómico familiar. Materiales y Métodos: Se registraron los valores la presión arterial sistólica y diastólica y se relevaron el peso y la talla de 3.312 escolares de ambos sexos. Se determinaron los casos de PAE, sobrepeso y obesidad y se calcularon prevalencias por sexo y edad. La información socioeconómica familiar fue obtenida a través de una encuesta y procesada mediante análisis de componentes principales. Las prevalencias de PAE se compararon por sexo, edad, estado nutricional (pruebas de chi cuadrado) y nivel socioeconómico familiar (modelo lineal generalizado) (p< 0,05). Resultados: El 20.5% de los escolares presentó PAE, con variaciones de acuerdo a la edad, el estado nutricional y el nivel socioeconómico. Sólo se observaron diferencias sexuales en los escolares obesos. Conclusiones: Los niños y adolescentes que viven en áreas periféricas de la ciudad de La Plata presentan elevadas prevalencias de PAE. Aquellos con sobrepeso/obesidad, con edades >8 años y los provenientes de familias con nivel socioeconómico más favorable evidencian mayores prevalencias de PAE. Los varones obesos son más propensos que las mujeres obesas a presentar presión arterial elevada.

Menarca y estado nutricional en niñas del periurbano de la ciudad de La Plata, Argentina / Menarche and nutritional status in peri-urban girls of La Plata city, Argentina

La menarca constituye un hito madurativo importante. A escala mundial ocurre, en promedio, a los 12,5 años y está sujeta a factores genéticos y/o ambientales. El objetivo fue analizar, en niñas residentes en la periferia urbana de La Plata: a) la edad mediana de menarca y b) si el estado nutricional y la distribución adiposa influyen en la edad de ocurrencia de menarca. Se evaluaron, durante los ciclos 2014-2017, en 657 niñas de 10-14 años: presencia(P)/ausencia(A) de menarca, peso, talla y pliegues subcutáneos tricipital y subescapular. Se determinaron: edad mediana de menarca (EM) según método status quo y regresión logística; estado nutricional -desnutrición, exceso ponderal y normonutrición- empleando como referencia y puntos de corte a la OMS; y distribución de adiposidad según índice subescapular/tricipital, considerando valores >1 indicativos de adiposidad centralizada. Se calcularon en general y por estado nutricional la EM y las prevalencias de ocurrencia comparándose mediante Chi2. La menarca estuvo presente en el 44,10% de las niñas con EM de 12,13 años. Alrededor del 54% de las niñas se mantuvo dentro de los límites normales (P: 41,20%; EM: 12,28 años) y el 45,70% estaban desnutridas; de estas 4,90% mostraron desnutrición debido a la baja estatura (P: 25,00%; MS: 13,40 años) y 40,80% tenían exceso de peso (P: 50,40%; MS: 11,78 años). El 32,72% de las niñas tenían adiposidad centralizada (P: 59,10%; EM: 11,79 años). Los resultados permiten concluir que el estado nutricional influye en la edad mediana de ocurrencia de la menarca, la cual es mayor en las niñas desnutridas y menor en las niñas con exceso ponderal. La disposición centralizada de la adiposidad favorece la presencia de menarca(AU)

Menarche is an important maturation milestone. It normally occurs at an average age of 12.5 years and is influenced by genetic and/or environmental factors. The aim of this study was to analyze in girls residing at suburbs of La Plata city a) the median age of menarche; b) if nutritional status and fat distribution have any influence in the age of menarche. During years 2014 to 2017, 657 girls aged between 10 and 14 years(y) were surveyed, determining: presence(P)/absence(A) of menarche, weight, height, and tricipital and subscapular skinfolds. It was measured: median age of menarche (MA) according to the status quo method and logistic regression; nutritional status -undernutrition, excess weight, and normonutrition- using WHO as a reference and their cut-off points; and the distribution of adiposity through the use of subscapular/tricipital index, considering values >1 an indicative of centralized adiposity. The median age of menarche was calculated both in the general sample and by nutritional status; general and age-prevalence of menarche were compared by Chi2. Menarche was present in 44.10% of the girls with MS of 12.13 years. About 54% of the population stayed within normal limits (P: 41.20%; MS: 12.28 years) and 45.70% were malnourished; of these 4.90% showed malnutrition due to short stature (P: 25.00 %; MS: 13.40 years) and 40.80% had weight excess (P: 50.40%; MS: 11.78 years). 32.72% of the girls had centralized adiposity (P: 59.10%; MS: 11.79 years). These results allow us to conclude that nutritional status influences the median age of menarche: it is higher in undernourished girls and lower in those with weight excess. Centralized disposition of adiposity promotes the presence of menarche(AU)

Comparative study of mid-upper arm circumference, arm muscle area and arm fat area percentiles in Argentinean and US children aged 4-14 years.

INTRODUCTION: Background: mid-upper arm circumference (MUAC), subcutaneous fat and muscle measurements are an alternative method to diagnose overweight and evaluate growth as well as protein and energy reserves. Aim: to compare MUAC, arm muscle area (AMA) and arm fat area (AFA) measurements of Argentinean boys and girls (Sa) with reference curves for US boys and girls (R). Subjects and methods: data from 22,736 school-children aged 4-14 years from six Argentinean provinces were collected. MUAC and triceps skinfold thickness were measured and the derived AMA and AFA measures were calculated. Analyses were performed with GAMLSS using the R software. Differences in mean values of Sa and R were compared in percentiles 3, 50 and 97. Results: mean values of MUAC and AMA in boys and girls were higher in R than in Sa at all ages; conversely, AFA values were lower. Conclusions: our results confirm differences in upper arm anthropometry of Argentinean school-children with respect to the US reference. The higher adipose tissue and lower skeletal muscle mass observed in Argentinean children could be partly associated with the different ethnic origin of both populations. However, differences should be interpreted in the context of an obesogenic environment, which has favored a calorie-protein imbalance.

INTRODUCCIÓN: Antecedentes: la medición de la circunferencia del brazo (MUAC), así como la estimación de la grasa subcutánea y muscular constituyen un método alternativo para diagnosticar el sobrepeso y evaluar el crecimiento y las reservas proteicas y energéticas. Objetivo: comparar las mediciones de MUAC, área muscular (AMA) y área grasa (AFA) del brazo de niños y niñas argentinos (Sa) con curvas de referencia para niños y niñas de Estados Unidos (R). Sujetos y métodos: se recopilaron datos de 22,736 escolares de 4 a 14 años de edad de seis provincias argentinas. Se obtuvieron medidas de MUAC y pliegue subcutáneo tricipital y se calcularon AMA y AFA. Los análisis se realizaron con GAMLSS utilizando el software R. Las diferencias en los valores medios de Sa y R se compararon para los percentiles 3, 50 y 97. Resultados: a todas las edades los valores medios de MUAC y AMA en niños y niñas fueron más altos en R que en Sa; por el contrario, los valores de AFA fueron más bajos. Conclusiones: nuestros resultados confirman la existencia de diferencias en la antropometría mesobraquial de los niños argentinos con respecto a los de la referencia. La mayor cantidad de tejido adiposo y menor de tejido muscular observada en los niños argentinos de ambos sexos puede ser parcialmente asociada con el diferente origen étnico de ambas poblaciones. Sin embargo, las diferencias podrían interpretarse en el contexto de un ambiente obesogénico, el cual habría favorecido el desbalance proteico-calórico.

Crecimiento y desarrollo de niñas y niños que viven en entornos carcelarios de la provincia de Buenos Aires, Argentina / Growth and development of children living in prison environments of the province of Buenos Aires, Argentina

Objetivos: Examinar el estado nutricional, el desarrollo psicomotor y socioemocional de niñas y niños (a partir de ahora niños) que viven con sus madres en la Unidad Penal N° 33 de la provincia de Buenos Aires, Argentina. Materiales y métodos: Se registraron el sexo, la edad, el peso y la estatura de los niños (37) residentes con sus madres (28) en la Unidad Criminal No. 33 del SPB. Se calcularon los indicadores nutricionales y se analizaron según la referencia internacional de la Organización Mundial de la Salud (WHO/OMS) de 2006. Se evaluó el desarrollo infantil con la Prueba Nacional de Pesquisa (PRUNAPE) y el cuestionario socioemocional Ages and Stages Questionnaires: Socio-Emotional(R), Second Edition (ASQ:SE-2). Resultados: En la evaluación antropométrica se identificó: en menores de dos años, el 7% con bajo peso, el 3% con alerta de bajo peso, el 28% con alto peso y el 14% con baja talla. En mayores de dos años, el 37,5% tienen alto peso; y el 25%, riesgo de sobrepeso. No se encontró baja talla. En las pruebas PRUNAPE y ASQ:SE-2, de los 30 casos que completaron ambas pruebas, el 53,3% obtuvo puntuaciones dentro de lo esperado. En el grupo con ambas pruebas que no pasaron la PRUNAPE (n=9), el resultado encontrado en el ASQ:SE-2 fue que el 66,6% se hallaba dentro de las expectativas, y el 33,3%, en riesgo. En el grupo de niños con ambas pruebas que no pasaron el ASQ:SE-2, ninguno resolvió la PRUNAPE. Conclusión: Se registraron prevalencias elevadas de exceso de peso y altos porcentajes de riesgo en el desarrollo psicomotor, considerablemente superiores que en la población general. Se plantea la necesidad de acciones que disminuyan el efecto nocivo del internamiento en la infancia

Objective: The objective of this study was to examine the nutritional status, psychomotor and socioemotional development of children living with their mothers in prison in the province of Buenos Aires, Argentina. Material and method: Sex, age, weight and height were measured in children (37) residing with their mothers (28) in Prison No.33 of the SPB. Nutritional indicators were calculated and analyzed according to the WHO international reference (2006). National Research Test (PRUNAPE) and the parental questionnaire Ages and Stages Questionnaires: Socio-Emotional(R), Second Edition (ASQ:SE-2) were applied to evaluate development. Results: Anthropometric evaluation showed that 7% of children under 2 years presented low weight, 3% alert of low weight, 28% high weight and 14% low height. Children over 2 years of age showed 37.5% of high weight and 25% of risk of overweight. There were no children with short stature. PRUNAPE and ASQ:SE-2 tests: in the 30 cases that completed both tests more than half (53.3%) obtained scores within the expected range. In the group of children with both tests who did not pass the PRUNAPE (n = 9), the result found in the ASQ-SE 2 was diverse: 66.6% within expectations and 33.3% at risk. Neither of children with both tests who did not pass the ASQ:SE-2 passed the PRUNAPE. Conclussion: There were high prevalences of excess weight and high percentages of risk in psychomotor development, considerably higher than in the general population. There is a need to take action to reduce the harmful effect of childhood confinement

[Comparative study of the nutritional status of children living in four counties of the province of Buenos Aires (Argentina), in the context of nutrition transition]. / Estudio comparativo del estado nutricional de niños y niñas residentes en cuatro partidos de la provincia de Buenos Aires (Argentina), en el marco de la transición nutricional.

The aim of this study was to evaluate and compare the nutritional status of child populations living in four counties of the province of Buenos Aires to observe differences related to particular environmental and socioeconomic contexts in the framework of the nutrition transition. During the school years corresponding to the 2008-2012 period, weight and height were measured and body mass index was calculated for 7,873 school children between the ages of 4 and 12 years from the counties of La Plata, Brandsen, Magdalena and Punta Indio. Information about the contexts of residence was obtained using self-administered structured surveys. About 40% of schoolchildren presented malnutrition, with a prevalence of overweight in La Plata, obesity in Punta Indio and undernutrition in Magdalena. The nutritional status of the study populations was associated with the socioenvironmental conditions of residence, indicating that these populations are at different stages of the nutrition transition process.

El objetivo fue evaluar y comparar el estado nutricional en poblaciones infanto-juveniles residentes en cuatro partidos de la provincia de Buenos Aires y observar si existen diferencias vinculadas a los contextos ambientales y socioeconómicos particulares, en el marco de la transición nutricional. Entre los ciclos lectivos 2008-2012, se relevó el peso y la talla y se calculó el índice de masa corporal de 7.873 escolares, entre 4 y 12 años de edad, residentes en los partidos de La Plata, Brandsen, Magdalena y Punta Indio. La información acerca del contexto de residencia se obtuvo mediante encuesta estructurada y autoadministrada. Alrededor del 40% de los escolares presentó malnutrición, y prevalecieron el sobrepeso en La Plata, la obesidad en Punta Indio y la desnutrición en Magdalena. El estado nutricional se vinculó con las condiciones socioambientales de residencia y dio cuenta de que estas poblaciones se ubican en distintas etapas del proceso de transición nutricional.

Estudio comparativo del estado nutricional de niños y niñas residentes en cuatro partidos de la provincia de Buenos Aires (Argentina), en el marco de la transición nutricional / Comparative study of the nutritional status of children living in four counties of the province of Buenos Aires (Argentina), in the context of nutrition transition

RESUMEN El objetivo fue evaluar y comparar el estado nutricional en poblaciones infanto-juveniles residentes en cuatro partidos de la provincia de Buenos Aires y observar si existen diferencias vinculadas a los contextos ambientales y socioeconómicos particulares, en el marco de la transición nutricional. Entre los ciclos lectivos 2008-2012, se relevó el peso y la talla y se calculó el índice de masa corporal de 7.873 escolares, entre 4 y 12 años de edad, residentes en los partidos de La Plata, Brandsen, Magdalena y Punta Indio. La información acerca del contexto de residencia se obtuvo mediante encuesta estructurada y autoadministrada. Alrededor del 40% de los escolares presentó malnutrición, y prevalecieron el sobrepeso en La Plata, la obesidad en Punta Indio y la desnutrición en Magdalena. El estado nutricional se vinculó con las condiciones socioambientales de residencia y dio cuenta de que estas poblaciones se ubican en distintas etapas del proceso de transición nutricional.

ABSTRACT The aim of this study was to evaluate and compare the nutritional status of child populations living in four counties of the province of Buenos Aires to observe differences related to particular environmental and socioeconomic contexts in the framework of the nutrition transition. During the school years corresponding to the 2008-2012 period, weight and height were measured and body mass index was calculated for 7,873 school children between the ages of 4 and 12 years from the counties of La Plata, Brandsen, Magdalena and Punta Indio. Information about the contexts of residence was obtained using self-administered structured surveys. About 40% of schoolchildren presented malnutrition, with a prevalence of overweight in La Plata, obesity in Punta Indio and undernutrition in Magdalena. The nutritional status of the study populations was associated with the socioenvironmental conditions of residence, indicating that these populations are at different stages of the nutrition transition process.

Secular changes in body size and body composition in schoolchildren from La Plata City (Argentina).

AIM: To analyze the secular changes in body size and composition of two cohorts of children from La Plata City, Argentina, with a 35-year follow-up. subjects and methods: Cohort 1 (C1) was measured in 1969-1970 and included 1772 children (889 boys, 883 girls), and Cohort 2 (C2), measured in 2004-2005, included 1059 children (542 boys, 517 girls). Both cohorts were obtained from matching geographical areas and comprised children from 4 to 12 years. Body weight (W); Height (H); Upper arm circumference (UAC); Tricipital (TS) and Subscapular skinfolds (SS) were measured, and Body Mass Index (BMI) and muscle (UMA) and fat (AFA) brachial areas were calculated. Prevalence of overweight and obesity was estimated by IOTF. To compare C1-C2 we used a generalized linear model with log-transformed variables, and chi square test. RESULTS: There were significant and positive differences between C2-C1 in W, UAC, SS, TS, and AFA. In contrast, H was not significantly different and UMA was significantly different but with negative values. The prevalence of overweight and obesity was 14.5% and 3.8% in C1, and 17.0% and 6.8% in C2. Differences between cohorts were significant for obesity. CONCLUSION: The shifts observed for soft tissues--positive trend for fat and negative for muscle area--occurring without changes in height lead us to suppose that in these three decades, La Plata's population has experienced deterioration in living conditions and important changes in their lifestyle, such as an increased consumption of energy-dense foods and sedentary habits.

A comparative study on nutritional status and body composition of urban and rural schoolchildren from Brandsen district (Argentina).

The purpose of this study was to analyze whether nutritional status and body composition varies according to the environment of residence (urban or rural) of children in the Brandsen district (Argentina). Weight, height, arm circumference and tricipital and subscapular skinfolds were performed in 1368 schoolchildren aged 3 to 14. NHANES III reference was used to estimate nutritional status -underweight, stunting, wasting, overweight, and obesity- and to evaluate body composition -deficit and excess of adipose (DA, EA) and muscular (DM, EM) tissues of the arm-. Central fat distribution (CFD) was estimated using the subscapular-tricipital index. A structured questionnaire was implemented to evaluate socio-environmental characteristics. Nutritional categories based on body size and body composition were compared between urban and rural areas of residence using Chi-squared tests (χ2). The results indicated for the total sample: 1.1% underweight, 6.9% stunting, 0.4% wasting, 12.1% overweight, 9.7% obesity, 22.0% DM, 2.5% EM, 0.1% DA, 17.6% EA, and 8.5% CFD. Significant differences between urban and rural areas were found only for CFD. The socio-environmental analysis showed that while access to public services and housing quality was significantly better in the urban area, a considerable number of city households lived under deficient conditions, lacked health insurance and had low socioeconomic level. Fifty-three percent of the undernourished children had DM without urban-rural significant differences, and none of them showed DA. In the overweight plus obesity group, 62.8% presented EA, 6.4% EM, 4.7% DM, and 22.8% CFD. The highest percentages of DM and CFD were recorded in rural areas (p = 0.00). We conclude that the child population shows the "double burden" of malnutrition. The environment of residence does not promote any differentiation in the nutritional status. Nevertheless, the increment of central adiposity and, in some cases of muscle deficit in rural children, suggests a consumption of unbalanced diet.

Growth of functional cranial components in rats with intrauterine growth retardation after treatment with growth hormone.

The goal of this study was to analyse the effect of growth hormone (GH) on catch-up growth of functional facial (splanchnocranial) and neurocranial components in rats with intrauterine growth retardation (IUGR). Wistar rats were divided into the following groups: control (C), sham-operated (SH), IUGR, and IUGR + GH. IUGR was surgically induced and GH was administered between 21 and 60 days of age. Radiographs were obtained at 1, 21, 42, 63, and 84 days of age in order to measure length, width, and height of neurocranium (NL, NW, and NH) and face length, width, and height (FL, FW, and FH). Analysis of variance was performed at 1 day of age and a principal components analysis (PCA) at 84 days of age. Neurocranial and facial volumetric indexes were calculated as NVI = (3)√NL × NW × NH and FVI = (3)√FL × FW × FH, respectively, and adjusted by non-linear regression analysis. On postnatal day 1, there were significant differences between SH and IUGR (P < 0.01). Also, in both genders, final neurocranial volume was similar between SH and IUGR + GH groups, while the IUGR group had the lower value (P < 0.01). Final facial volume was similar among the three groups. In both genders, facial growth rates were SH = IUGR > IUGR + GH (P < 0.01). The first axis of the PCA exhibited size effect and the second axis showed shape effect. Reductions of placental blood flow modify cranial growth. The functional neurocranial and facial components in rats with IUGR presented different recovery strategies through modular behaviour, mainly related to modifications of growth rate as response to GH administration.

Bone growth and sexual dimorphism at birth in intrauterine-growth-retarded rats.

This paper addresses the effect of a reduction of uterine blood flow (RUB) on postcranial bone growth in rats. The objectives were: (1) to discover and characterize the changes evoked by growth retardation through a reduction in placental blood flow, (2) to see if the resulting growth retardation is different in each bone, and (3) to analyze any sex-specific features. RUB was induced by the partial bending of uterine vessels at day 1 of pregnancy. Control and sham-operated animals were also included. The animals were X-rayed at birth. The lengths and widths of the humerus, radius, and femur and pelvic length, interischial, interpubic, and pubic widths were measured. Data were analyzed by ANOVA and LSD post hoc tests. The intersubject analysis showed significant differences between groups and non-significant differences between sexes. In males, sham-operated and RUB showed significant differences in pelvic lengths and widths, and humeral, radial, femoral, and tibial widths. In females, there were significant differences only for humeral widths, radial lengths and widths, and femoral and tibial widths. We conclude that reduced blood flow delays appendicular bone growth as observed at birth. Pelvic length was more affected than that of the limbs. The widths of the pelvic and limbs bones, in turn, were more altered than the lengths, and the growth of the males more than that of the females. Partial bending of uterine vessels compromised postcranial growth, though under such disadvantageous circumstances the females proved to be more capable of growing and thus more resilient than the males.