Malnutrition and intestinal parasitosis: Current prevalences and risk factors among schoolchildren in Misiones (Argentina).

OBJECTIVES: To assess the current prevalences of nutritional status and intestinal parasites, and their potential association with socio-environmental conditions among schoolchildren in Aristóbulo del Valle, Misiones. METHODS: We measured body weight and height in 444 schoolchildren aged 3-14 years and evaluated their nutritional status following WHO criteria. We examined fecal samples and anal swabs from 234 schoolchildren and collected socio-environmental data through questionnaires. RESULTS: The prevalence of undernutrition was 4.5% and excess of weight was 24.1%. The prevalence of stunting and of being overweight reached 2.3% and 12.4%, respectively. About 42% of the schoolchildren were infected with at least one of the 12 species identified. The most prevalent species were Blastocystis sp., Enterobius vermicularis, and Giardia lamblia. Entamoeba dispar was recorded for the first time in the locality. The multiple correspondence analysis identified peri-urban, urban, and rural groups. Underweight, stunting and obesity were highest in the peri-urban group, while overweight, wasting and parasitism rates were highest in the rural group. The urban group showed the lowest parasitic prevalences. Bed-sharing, mother's education, and animal husbandry were associated with parasitic infections. CONCLUSIONS: The study highlights a decrease in undernutrition but a rise in overweight and obesity, indicating an ongoing nutritional transition. The association between socio-environmental risk factors and parasitic infections underscore the need for comprehensive interventions addressing both nutritional and socio-environmental conditions to improve the population's life quality.

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.

Changes in the prevalence of undernutrition, overweight and obesity in children and adolescents from Buenos Aires, Mendoza, and Misiones provinces (Argentina) over the last two decades.

OBJECTIVES: The aim of this study was to determine changes in the prevalence of undernutrition, overweight and obesity in Argentine children and adolescents over the last two decades, and analyze their relationship with family socioeconomic conditions. METHODS: We compared data in two cross-sectional studies (C) of schoolchildren (n: 4971) aged 4 to 13 years from three provinces: Buenos Aires, Mendoza and Misiones. C1 was carried out between 2005 and 2009 and C2 between 2010 and 2019. Anthropometric (body weight, height, triceps and subscapular skinfolds) and socioeconomic data of both studies were obtained in the same schools by the same investigators, using a similar methodology. The prevalence of nutritional status and the frequency of family socioeconomic conditions were calculated by province and C. Data were analyzed by chi square test, categorical principal component analysis and generalized linear model. RESULTS: The prevalence of undernutrition decreased in C2 in Buenos Aires and Misiones and remained constant in Mendoza. At the same time, the prevalence of overweight and obesity increased in the three provinces, around 13% in Buenos Aires and 9% in Mendoza and Misiones. Similarly, fat mass increased in C2. Undernutrition was associated with inadequate family socioeconomic conditions only in C1. CONCLUSIONS: This 14-year follow-up study shows a decreasing trend in the prevalence of undernutrition and an increasing trend in the prevalence of overweight, obesity, and fat mass in the child and adolescent population of Argentina. Also, a marked deterioration in family socioeconomic conditions was found, but its relationship with the changes in nutritional status remains to be elucidated.

Intestinal parasites in child and youth populations of Argentina: Environmental factors determining geographic distribution.

The transmission of intestinal parasites is generally considered to be "mediated by the environment" which suggests that they are particularly sensitive to the changes that occur in it. The aim of the present study was to evaluate the environmental variables that act as risk factors for intestinal parasitosis in children and youths in Argentina. The association between environmental variables related to temperature, precipitation and soil and parasitosis found in children and youths from different provinces was evaluated, including land use/cover classes obtained from satellite images. Of the total population analyzed, 66.9% of the participants were parasitized. The total number of identified parasite species was 17 and the most prevalent were Blastocystis sp. (42.2%), Enterobius vermicularis (33.6%) and Giardia lamblia (17.0%). Infection by protozoa, and by G. lamblia in particular, was greater when the mean summer temperature was higher (OR=1.2 for both). Blastocystis sp. and geohelminths were greater due to an increase in isothermality (OR=1.1 and 1.2, respectively). The risk of infection with Ascaris lumbricoides was associated with an increase in the temperature in the wettest quarter (OR=1.2). Hookworm infection was associated with an increase in the normalized difference vegetation index (OR=32.5). Most of participants infected with hookworms lived in areas with abundant arboreal-shrubby and agropastoral use vegetation. The heterogeneous distribution of enteric parasites is indicative of the wide environmental variability of Argentina.

[Cross-sectional study of intestinal parasitosis in child populations in Argentina]. / Estudio transversal de las parasitosis intestinales en poblaciones infantiles de Argentina.

OBJECTIVE: Determine the distribution of intestinal parasitosis in children in nine provinces representative of Argentina's mosaic of contrasting environments. METHODS: Descriptive, observational, cross-sectional study of preschool children (5 years old or under) and school-age children (6-14 years) in the provinces of Buenos Aires (sample taken between 2005 and 2013), Chubut (2010-2013), Corrientes (2012), Entre Ríos (2010-2012), Formosa (2014), La Pampa (2006), Mendoza (2008-2011), Misiones (2005-2008 and 2013), and Salta (2012-2013). Serial samples, fecal samples, and anal swabs were processed using concentration techniques. The results were analyzed by sex, age interval, and province. Frequency of parasitosis (monoparasitosis and multiple parasitoses), wealth of species, and Sørensen similarity coefficient were calculated. RESULTS: Misiones presented the highest frequency of parasitized children and Chubut the lowest (82.0% vs 38.4%; p < 0.01). The number of species was greatest in Misiones and Buenos Aires and lowest in Chubut and La Pampa. Men were parasitized more than women only in Buenos Aires. The highest frequencies were found in preschool children in Buenos Aires and schoolchildren in Mendoza and Misiones (p < 0.05). Monoparasitosis was most frequent in Chubut (67.9%) and multiple parasitosis in Formosa (69.2%). The most frequent species in the majority of provinces were Blastocystis sp. and Enterobius vermicularis. Misiones presented the highest frequency of soil-transmitted helminthes (23.3%) and Mendoza the lowest (0.6%); none were found in Chubut, La Pampa, or Salta. Buenos Aires, Formosa, and Misiones presented a similar species composition, as did Chubut and La Pampa. CONCLUSIONS: The frequency of parasitosis in Argentina corresponds to the country's complex mosaic of climatic and socioeconomic variability and shows a declining trend from north to south and from east to west.

Malnutrition and body composition in urban and rural schoolchildren: A cross-sectional study in San Rafael, Mendoza (Argentina).

OBJECTIVES: The aim of the present study was to analyze the nutritional status and body composition of children from San Rafael, Mendoza, avoiding urban and rural categorization by generating subpopulations as a function of their socio-environmental characteristics. METHODS: A cross-sectional study was performed in 3,596 schoolchildren from 4.0 to 13.9 years of age. Body weight, height, upper arm circumference, and triceps skinfold were measured. Body mass index, total muscle, and fat areas of the arm were calculated. To estimate nutritional status and body composition, the NHANES III reference was used. The socio-environmental variables were surveyed using a structured questionnaire. These variables were processed by categorical principal-component analysis (catPCA). RESULTS: The catPCA allowed the differentiation of four groups, three with urban characteristics (high urban, medium urban, impoverished urban), and a rural group. Stunting occurred at a higher rate in the impoverished urban group, and the occurrence of underweight children was higher in the rural group. The prevalence of excess weight varied in the range of 20-26%. The latter value corresponded to children of the high urban group, who also did not show reduced muscle mass. CONCLUSION: Children from San Rafael presented differences in nutritional condition and body composition associated with pronounced socio-environmental heterogeneity. Thus, we could observe a gradient from the "high urban" group, with better social, economic, and sanitation conditions and at the same time a more obesogenic environment to the "impoverished urban" and "rural" groups, whose vulnerability reflected a higher prevalence of child undernutrition and the association with excess weight and reduced muscle mass. Am. J. Hum. Biol. 28:796-803, 2016. © 2016Wiley Periodicals, Inc.

Weight and height percentiles calculated by the LMS method in Argentinean schoolchildren. A comparative references study.

BACKGROUND: The Argentinean population is characterized by ethnic, cultural and socio-economic diversity. AIM: To calculate the percentiles of weight-for-age (W/A) and height-for-age (H/A) of schoolchildren from Argentina employing the LMS method; and to compare the obtained percentiles with those of the international and national references. SUBJECTS AND METHODS: Anthropometric data of 18 698 students (8672 girls and 10 026 boys) of 3-13 years old were collected (2003-2008) from Buenos Aires, Catamarca, Chubut, Jujuy, La Pampa and Mendoza. Percentiles of W/A and H/A were obtained with the LMS method. Statistical and graphical comparisons were established with the WHO (international reference) and with that published by the Argentinean Paediatric Society (national reference). RESULTS: Differences in W/A and H/A, regarding the references, were negative and greater at the highest percentiles and in most of the age groups. On average, the differences were greater for boys than girls and for national than international references. CONCLUSION: The distribution of weight and height of schoolchildren, coming from most regions of the country, differs from those of national and international references. It should be advisable to establish a new national reference based on internationally recognized methodological criteria that adequately reflect the biological and cultural diversity of the Argentinean populations.

[Theories of biological aging: An integrative review]. / Teorías del envejecimiento biológico: una revisión integradora.

In this article, we review the main theories of biological aging, exploring the interaction of genetic, epigenetic, metabolic, immunological, and ecological factors in this process. For this purpose, we examine and discuss theories such as the allocation of metabolic resources, pleiotropic antagonism, genetic regulation, codon restriction, replicative senescence, action of free radicals, caloric restriction, catastrophic error, immunological theory, neuroendocrine theory, programmed aging, epigenetics of aging, grandmother and caregiver theories and ecological biophysical theory. We identify the contribution of different biological mechanisms to aging, emphasizing the complementarity of theories such as the allocation of metabolic resources, pleiotropic antagonism, and caloric restriction, providing a more comprehensive view of the phenomenon. In conclusion, we highlight the need to consider diverse perspectives in aging research, recognizing the absence of a single explanation. Integrating these theories is crucial to comprehensively understand the process and develop effective interventions in health and well-being in old age.

Excess weight and changes in body composition in boys and girls from La Plata district (Buenos Aires, Argentina) - a study with a secular perspective.

The aim of the present study was to advance knowledge of the secular changes in the prevalence of excess weight (overweight and obesity) and body composition of children living in different localities of La Plata district (Buenos Aires province, Argentina) over the last two decades. For this purpose, anthropometric data and information on the socioeconomic and environmental context of residence of schoolchildren aged 4.0-12.9 years collected during 2005-2009 (Cohort 1, n = 1 233) and 2016-2019 (Cohort 2, n = 1 499) were analysed and compared. From a secular perspective, the current analysis showed that the socioeconomic and environmental conditions of families living in La Plata district have deteriorated in recent decades. In this context, child excess weight increased by 13% and body composition was altered, mainly as a result of an increase in fat mass, without observing changes in the muscle component.

Body mass index, weight, and height percentiles in school-aged children from Mendoza. A comparison with the WHO reference. / Percentiles de peso, talla e índice de masa corporal de escolares de Mendoza. Comparación con la referencia de la Organización Mundial de la Salud.

Introduction. The World Health Organization (WHO) recommends the use of reference tables to monitor the growth pattern and nutritional status of children and adolescents. Body mass index (BMI), weight, and height are the most commonly used variables. The objective of this study was to estimate the BMI, weight, and height percentiles for school-aged children (2009-2011) living in the department of San Rafael (Mendoza) and compare them to the international World Health Organization reference to establish their relevance for the evaluation of the growth pattern and nutritional status of this population. Population and methods. A cross-sectional anthropometric study was conducted in 3448 school-aged children aged 4.00 to 13.49 years. The LMS ChartMarker Pro software was used to estimate the BMIfor-age, weight-for-age, and height-for-age percentiles, by sex and age, and they were compared with the WHO curves. Besides, percentage differences (%D) were calculated to estimate the differences and their statistical significance using the Wilcoxon test. Results. The population of boys and girls in San Rafael showed higher weight and BMI (%D ≈ 7% and 9%, respectively) percentiles, and lower height (%D ≈ 0.8%) values than WHO reference (p < 0.05). Conclusion. The differences found warn about the use of the WHO reference in the school-aged population of San Rafael since it would overestimate the prevalence of overweight, obesity, and chronic malnutrition and underestimate the prevalence of acute and global malnutrition. This situation highlights the importance of having a local reference resource.

Introducción. La Organización Mundial de la Salud (OMS) recomienda el uso de tablas de referencia para monitorear el crecimiento y estado nutricional de niños, niñas y adolescentes. El peso corporal, la talla y el índice de masa corporal (IMC) son las variables más utilizadas. El presente trabajo tiene como objetivos estimar los percentiles de peso, talla e IMC de escolares (2009-2011) residentes en el departamento San Rafael (Mendoza) y compararlos con la referencia internacional de la Organización Mundial de la Salud, a fin de establecer su pertinencia para la evaluación del crecimiento y estado nutricional de dicha población. Población y métodos. Se realizó un estudio antropométrico transversal en 3448 escolares de entre 4,00 y 13,49 años de edad. Se utilizó el programa LMS ChartMarker Pro para calcular los valores percentilares de peso/edad, talla/edad e IMC/edad, por sexo y edad, y se compararon con las curvas de la OMS. Además, se calcularon diferencias porcentuales (D%) para estimar las diferencias y su significación estadística mediante prueba de Wilcoxon. Resultados. La población de San Rafael mostró, en varones y mujeres, valores percentilares superiores de peso e IMC (D% ≈7 % y 9 %, respectivamente), y menores de talla (D% ≈0,8 %) que los de la OMS (p <0,05). Conclusión. Las diferencias encontradas alertan sobre el empleo de la referencia OMS en la población escolar de San Rafael, ya que sobreestimaría las prevalencias de sobrepeso, obesidad y desnutrición crónica, y subestimaría la de desnutrición aguda y global. Esta situación resalta la importancia de contar con una referencia local.

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.

Reference percentiles for mid-upper arm circumference, upper arm muscle and fat areas in the Argentine child and adolescent population (4-14 years old). / Percentilos de referencia de la circunferencia y de las áreas muscular y grasa del brazo para la población infantojuvenil argentina (4-14 años).

INTRODUCTION: Mid-upper arm circumference (MUAC) is widely recognized as an adequate indicator of nutritional status. OBJECTIVE: To estimate the reference percentiles for MUAC, upper arm muscle area (UAMA), and upper arm fat area (UAFA) in the Argentine child and adolescent population using the LMS method (lambda, mu, sigma). MATERIALS AND METHODS: The sample was made up of schoolchildren aged 4.0-13.9 years living in Jujuy, Catamarca, Misiones, Buenos Aires, Mendoza, and Chubut. MUAC and tricipital skinfold anthropometric measurements were obtained between 2003 and 2008 as per standardized protocols. UAMA and UAFA were calculated, and percentiles by age and sex were estimated and compared using an analysis of variance. RESULTS: A total of 22 736 schoolchildren (11 397 boys and 11 339 girls) were included. The 50th percentile was higher for the MUAC and UAFA among girls and for the UAMA among boys. The MUAC curves showed sharper increases as of 7 years old in all percentiles among both boys and girls. A similar pattern was observed for the UAMA, with higher values among boys. Lastly, the UAFA showed a constant increase among girls and a stabilization among boys as of 11 years old. Differences for age were observed. CONCLUSIONS: The tabulated and plotted percentiles and the MUAC, UAMA, and UAFA may be used as local references for epidemiological and anthropological studies.

Introducción: La circunferencia del brazo (CB) se reconoce como buen indicador del estado nutricional. Objetivo: Estimar los percentilos de referencia para la CB y las áreas muscular (AM) y grasa (AG) del brazo en la población infantojuvenil argentina mediante el empleo del método LMS (lambda, mu, sigma, en inglés). Materiales y métodos: La muestra estuvo constituida por escolares de 4,0 a 13,9 años residentes en Jujuy, Catamarca, Misiones, Buenos Aires, Mendoza y Chubut. Las mediciones antropométricas de la CB y del pliegue tricipital se realizaron entre 2003 y 2008 siguiendo protocolos estandarizados. Se estimaron las AM, AG, se calcularon los percentilos por edad y sexo, y se compararon mediante el análisis de la varianza. Resultados: Se incluyeron 22 736 escolares (11 397 varones y 11 339 mujeres). Los valores correspondientes al percentilo 50 fueron superiores, en las mujeres, para CB y AG, y, en los varones, para AM. Las curvas de CB presentaron incrementos más marcados a partir de los 7 años en todos los percentilos, para ambos sexos. Un patrón similar se observó para AM, con valores superiores en los varones. Por último, el AG mostró aumento constante en las mujeres y estabilización en los varones a partir de los 11 años. Se observaron diferencias para la edad. Conclusiones: Los valores de percentilos, tabulados y graficados, de la CB y de las AM y AG del brazo pueden constituir una referencia local para estudios epidemiológicos y antropológicos.

[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.

Percentiles de peso, talla e índice de masa corporal de escolares de Mendoza. Comparación con la referencia de la Organización Mundial de la Salud / Body mass index, weight, and height percentiles in school-aged children from Mendoza. A comparison with the WHO reference

Introducción. La Organización Mundial de la Salud (OMS) recomienda el uso de tablas de referencia para monitorear el crecimiento y estado nutricional de niños, niñas y adolescentes. El peso corporal, la talla y el índice de masa corporal (IMC) son las variables más utilizadas. El presente trabajo tiene como objetivos estimar los percentiles de peso, talla e IMC de escolares (2009-2011) residentes en el departamento San Rafael (Mendoza) y compararlos con la referencia internacional de la Organización Mundial de la Salud, a fin de establecer su pertinencia para la evaluación del crecimiento y estado nutricional de dicha población. Población y métodos. Se realizó un estudio antropométrico transversal en 3448 escolares de entre 4,00 y 13,49 años de edad. Se utilizó el programa LMS ChartMarker Pro para calcular los valores percentilares de peso/edad, talla/edad e IMC/edad, por sexo y edad, y se compararon con las curvas de la OMS. Además, se calcularon diferencias porcentuales (D%) para estimar las diferencias y su significación estadística mediante prueba de Wilcoxon. Resultados. La población de San Rafael mostró, en varones y mujeres, valores percentilares superiores de peso e IMC (D% ≈7 % y 9 %, respectivamente), y menores de talla (D% ≈0,8 %) que los de la OMS (p <0,05). Conclusión. Las diferencias encontradas alertan sobre el empleo de la referencia OMS en la población escolar de San Rafael, ya que sobreestimaría las prevalencias de sobrepeso, obesidad y desnutrición crónica, y subestimaría la de desnutrición aguda y global. Esta situación resalta la importancia de contar con una referencia local.

Introduction. The World Health Organization (WHO) recommends the use of reference tables to monitor the growth pattern and nutritional status of children and adolescents. Body mass index (BMI), weight, and height are the most commonly used variables. The objective of this study was to estimate the BMI, weight, and height percentiles for school-aged children (2009-2011) living in the department of San Rafael (Mendoza) and compare them to the international World Health Organization reference to establish their relevance for the evaluation of the growth pattern and nutritional status of this population. Population and methods. A cross-sectional anthropometric study was conducted in 3448 school-aged children aged 4.00 to 13.49 years. The LMS ChartMarker Pro software was used to estimate the BMI- for-age, weight-for-age, and height-for-age percentiles, by sex and age, and they were compared with the WHO curves. Besides, percentage differences (%D) were calculated to estimate the differences and their statistical significance using the Wilcoxon test. Results. The population of boys and girls in San Rafael showed higher weight and BMI (%D ≈ 7% and 9%, respectively) percentiles, and lower height (%D ≈ 0.8%) values than WHO reference (p < 0.05). Conclusion. The differences found warn about the use of the WHO reference in the school-aged population of San Rafael since it would overestimate the prevalence of overweight, obesity, and chronic malnutrition and underestimate the prevalence of acute and global malnutrition. This situation highlights the importance of having a local reference resource

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)

Percentilos de referencia de la circunferencia y de las áreas muscular y grasa del brazo para la población infantojuvenil argentina (4-14 años) / Reference percentiles for mid-upper arm circumference, upper arm muscle and fat areas in the Argentine child and adolescent population (4-14 years old)

Introducción: La circunferencia del brazo (CB) se reconoce como buen indicador del estado nutricional. Objetivo: Estimar los percentilos de referencia para la CB y las áreas muscular (AM) y grasa (AG) del brazo en la población infantojuvenil argentina mediante el empleo del método LMS (lambda, mu, sigma, en inglés). Materiales y métodos: La muestra estuvo constituida por escolares de 4,0 a 13,9 años residentes en Jujuy, Catamarca, Misiones, Buenos Aires, Mendoza y Chubut. Las mediciones antropométricas de la CB y del pliegue tricipital se realizaron entre 2003 y 2008 siguiendo protocolos estandarizados. Se estimaron las AM, AG, se calcularon los percentilos por edad y sexo, y se compararon mediante el análisis de la varianza. Resultados: Se incluyeron 22 736 escolares (11 397 varones y 11 339 mujeres). Los valores correspondientes al percentilo 50 fueron superiores, en las mujeres, para CB y AG, y, en los varones, para AM. Las curvas de CB presentaron incrementos más marcados a partir de los 7 años en todos los percentilos, para ambos sexos. Un patrón similar se observó para AM, con valores superiores en los varones. Por último, el AG mostró aumento constante en las mujeres y estabilización en los varones a partir de los 11 años. Se observaron diferencias para la edad. Conclusiones: Los valores de percentilos, tabulados y graficados, de la CB y de las AM y AG del brazo pueden constituir una referencia local para estudios epidemiológicos y antropológicos.

Introduction: Mid-upper arm circumference (MUAC) is widely recognized as an adequate indicator of nutritional status. Objective: To estimate the reference percentiles for MUAC, upper arm muscle area (UAMA), and upper arm fat area (UAFA) in the Argentine child and adolescent population using the LMS method (lambda, mu, sigma) Materials and methods: The sample was made up of schoolchildren aged 4.0-13.9 years living in Jujuy, Catamarca, Misiones, Buenos Aires, Mendoza, and Chubut. MUAC and tricipital skinfold anthropometric measurements were obtained between 2003 and 2008 as per standardized protocols. UAMA and UAFA were calculated, and percentiles by age and sex were estimated and compared using an analysis of variance. Results: A total of 22 736 schoolchildren (11 397 boys and 11 339 girls) were included. The 50th percentile was higher for the MUAC and UAFA among girls and for the UAMA among boys. The MUAC curves showed sharper increases as of 7 years old in all percentiles among both boys and girls. A similar pattern was observed for the UAMA, with higher values among boys. Lastly, the UAFA showed a constant increase among girls and a stabilization among boys as of 11 years old. Differences for age were observed. Conclusions: The tabulated and plotted percentiles and the MUAC, UAMA, and UAFA may be used as local references for epidemiological and anthropological studies.