Inhibitory control and obesity in adolescents: A prospective cohort study.

INTRODUCTION: Inhibitory control (IC) is an executive function that plays a central role in the capability to control one's attention and behavior. Growing evidence suggests that deficits in IC are related to calorie consumption and obesity development. However, there are only a few studies that have addressed this issue prospectively. The aim of the present study was to evaluate the influence of IC on anthropometric changes at one year follow up in a cohort of Argentinian adolescents. METHODS: A prospective cohort study of 569 students (264 boys and 305 girls) aged 13.18 ± 0.36 years at initial evaluation and 14.22 ± 0.29 years at follow up was performed. IC was assessed at baseline and at follow up by means of a computerized Go/No-Go task, and anthropometric measures were performed following standardized procedures. At follow up an abbreviated Three Factor Eating Questionnaire (TFEQ-R21C) was performed. RESULTS: Cross sectional analysis performed at the age of 14 revealed an association between IC and obesity, meanwhile at the age of 13 IC was associated with the degree of obesity. Prospective analysis showed that a lower IC at baseline predicted a higher increase in body mass index (BMI) and waist circumference at one year of follow up. Subjects with lower IC at follow up rated higher in the uncontrolled eating domain of TFEQ-R21C and presented higher snacking frequency. CONCLUSIONS: A higher IC capacity at baseline might be associated with a more favorable evolution in BMI and waist circumference. A low IC at follow up is associated with obesity and higher uncontrolled eating. This suggests that the identification of subjects with low IC might be useful in order to detect adolescents at risk of obesity at earlier stages.

Short sleep and low milk intake are associated with obesity in a community of school aged children from Argentina.

OBJECTIVES: Understanding the factors related to obesity during childhood allows for improved preventive actions specifically adapted to particular communities. The purpose of this study was to identify individual and familiar factors related to obesity in children. METHODS: A cross-sectional study was conducted in an urban community in Argentina during the years 2015-2016. Weight and height were measured on a probabilistic sample of 1366 schoolchildren aged 6 to 12 years. BMI categories were established according to International Obesity Task Force (IOTF) cut-offs. Data were analyzed using multivariate and logistic regression models. Independent variables corresponded to four domains: anthropometric, socioeconomic and demographic, nutritional, and energy balance. RESULTS: Twenty percent of children were categorized as overweight (OW) and 12.2% were obese (OB). Parental IOTF grade was positively associated with childhood OW/OB (father B = 0.421 P = 0.000, OR = 1.52, 95% CI 1.24-1.88; mother B = 0.498 P = 0.000, OR = 1.65, 95% CI 1.37-1.97). The remaining variables were negatively associated with OW/OB: hours of sleep (B = -0.566 P = 0.001, OR = 0.57, 95% CI 0.41-0.79), physical activity (B = -0.362 P = 0.017, OR = 0.70, 95% CI 0-52-0.94), and daily milk intake (B = -0.178 P = 0.045, OR = 0.84, 95% CI 0.70-0.99). Parental IOTF predicted both OW and OB, while sleep hours predicted OW and physical activity predicted OB. CONCLUSIONS: Family should be considered the initial target for effective strategies to reduce obesity. Like physical activity, the promotion of milk and dairy intake, as well as sleep, may have a major role in obesity reduction because of their protective effects in this community.

Trend in childhood obesity reflects socioeconomic status in Argentina.

Background: Surveillance of childhood obesity is essential to guide preventive policies and interventions.Aim: To analyse trends in overweight and obesity by socioeconomic status (SES) in Argentinian schoolchildren during the last decade.Subjects and methods: Two cross-sectional studies in schoolchildren aged 6-12 years were compared. The first study was conducted in 2005/07 (n = 1418) and the second one in 2015/16 (n = 1366). Overweight and obesity were estimated by the International Obesity Task Force (IOTF) cut-offs. The type of school (public/private) and parental education level were used as measures of SES. Data were analysed by linear and logistic regression with survey year, type of school, parental education level, and sex as independent variables.Results: From 2005 to 2016 overweight and obesity increased by 7.3% and 5.0%, respectively. The change was significantly higher in boys (9.6% and 8.3%) and girls (9.6% and 5.4%) from public schools, and in children whose fathers had low (10% and 8.3%) and middle (9.0% and 5.5%) education levels. No significant changes were found in children attending private school or those whose fathers had a higher education level.Conclusions: Obesity is still increasing in this population. SES disparities are strongly associated with this trend, with stabilisation in children from high SES.

Weight and height centiles of Argentinian children and adolescents: a comparison with WHO and national growth references.

BACKGROUND: Studies in several countries comparing the performance of WHO references and their own national growth standards reported differences that could affect screening and growth monitoring. AIM: To estimate weight and height centiles on a sample of Argentinian children and adolescents and compare selected centiles with WHO and national growth references. SUBJECTS AND METHODS: A cross-sectional school survey was conducted on 6239 boys and girls aged 5-18. Data were collected between 2005-2009 in Santa Rosa, Argentina. Smoothed weight and height centiles were estimated by the LMS method and compared with WHO 2007 and Argentinian (ARG) growth references. RESULTS: Weight centiles were higher than those of WHO and ARG. Height centiles were above the ARG and below the WHO ones. The greatest differences with ARG were seen before puberty and then declined up to age 18. In contrast, differences with WHO increased from puberty onwards. CONCLUSION: Compared with the ARG reference, linear growth of these schoolchildren shows a secular acceleration without substantial improvements in the adult height. In relation to WHO, the results suggest that around the adolescent growth spurt differences in linear growth between populations became larger, limiting the clinical usefulness of international growth references in adolescents.

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.

Nutritional status in parasitized and nonparasitized children from two districts of Buenos Aires, Argentina.

UNLABELLED: The Program for the Control of Intestinal Parasites and Nutrition was designed to intervene in small communities to prevent and control the effects of parasitic infections on children's health. OBJECTIVES: To analyze the association between nutritional status and parasitic infection in suburban and rural children from Buenos Aires, Argentina. METHODS: Nutritional status was assessed by anthropometric (weight, height, BMI, skinfolds, upper arm circumference, muscle, and fat upper arm areas) and biochemical (Hb, Ca, Mg, Zn, and Cu) indicators. Parasitological analysis were made on both serial stool and perianal swab samples. A total of 708 children aged 3-11 were measured. The biochemical analysis included 217 blood samples and the parasitological study included 284 samples. RESULTS: Anthropometric status was similar in both settings with low rates of underweight and stunting (<6%), and high rates of overweight (~17%) and obesity (~12%). Ca deficiency was significantly higher in suburban children where 80% of them were hypocalcemic. Around 70% of fecal samples contained parasites. Among infected children, the most prevalent species were Blastocystis hominis and Enterobius vermicularis (~43%) followed by Giardia lamblia (~17%). Differences in parasitological status between districts were not significant. In the suburban district parasitized children were lighter, shorter, and had a lower upper arm circumference than their non-infected peers. No differences in anthropometric status were seen among infected and uninfected rural children. CONCLUSIONS: The results suggest an association between intestinal parasites and physical growth in suburban children. Rural children seem to be protected against the effects of parasitic infection.

Argentine and World Health Organization head circumference standards: A comparison study. / Estándares de perímetro cefálico argentinos y de la Organización Mundial de la Salud: estudio comparativo.

Introduction. Several studies have shown population differences in head circumference (HC) that question the universal validity of the World Health Organization (WHO) standard to assess head growth. Objectives. To compare the Argentine reference charts for HC from 0 to 5 years of age with the WHO standards. Population and methods. The 3rd and 97th percentiles for HC based on the Argentine reference charts were compared with the corresponding WHO standard and the percentage of children classified as having microcephaly (HC < 3rd percentile of the WHO) and macrocephaly (HC > 97th percentile of the WHO) at specific ages between 0 and 5 years were estimated. Results. The comparison of the Argentine reference charts with the WHO standards shows that, in both males and females, at the 3rd percentile, the Argentine reference charts are below the WHO standards from 1 to 6 months of age, similar from 9 to 18 months of age, and then above until 60 months old. In relation to the 97th percentile, the Argentine reference charts are above the WHO standards from birth to 60 months in both boys and girls. Conclusions. The head size of Argentine children is different from that established by the WHO standards. The adoption of the WHO standards for our population increases the percentage of macrocephaly diagnosis at all ages.

Introducción. Diversos estudios han evidenciado diferencias poblacionales en el tamaño cefálico que cuestionan la validez universal del estándar de la Organización Mundial de la Salud (OMS) para evaluar el crecimiento cefálico. Objetivos. Comparar las referencias argentinas de perímetro cefálico (PC) de 0 a 5 años con los estándares de la OMS. Población y métodos. Se compararon los percentiles 3 y 97 de PC de las referencias argentinas con los correspondientes del estándar de la OMS y se calcularon los porcentajes de niños clasificados como microcefálicos (PC < percentil 3 de la OMS) y macrocefálicos (PC > percentil 97 de la OMS) a edades específicas entre el nacimiento y los 5 años de edad. Resultados. La comparación de las referencias argentinas con los estándares de la OMS, muestra que ­en ambos sexos­ en el percentil 3, desde el primer mes y hasta los 6 meses, las referencias argentinas se encuentran por debajo de los estándares de la OMS, son similares entre los 9 y 18 meses, y luego se ubican por encima hasta los 60 meses. En relación con el percentil 97, las referencias argentinas se ubican por encima de los estándares de la OMS desde el nacimiento hasta los 60 meses en ambos sexos. Conclusiones. El tamaño cefálico de los niños y niñas argentinos difiere del de los estándares de la OMS. La adopción de los estándares de la OMS en nuestra población incrementa el porcentaje de diagnóstico de macrocefalia a todas las edades.

Argentine reference charts for head circumference from birth to 19 years of age. / Referencias argentinas de perímetro cefálico desde el nacimiento hasta los 19 años.

Introduction. Head circumference (HC) is an indicator of brain growth; growth charts are necessary to determine normal or pathological variations. Objectives. To present the first Argentine HC reference charts between birth and 19 years of age and to compare them with the Nellhaus charts, which have been used in our country to date. Population and methods. These references were developed based on combined data from the National Survey on Nutrition and Health of 2018 and cross-sectional studies conducted between 2004 and 2007 in the provinces of Buenos Aires and La Pampa, which included 8326 healthy children and adolescents. Growth curves were adjusted using the LMS method. To assess the differences between these reference charts and the Nellhaus charts, at different ages, the 2nd, 50th, and 98th percentiles were plotted. Results. HC showed a variable increase in size with age, which was greater in the first years of life, and a slight increase at puberty. The values for the 98th percentile of the Argentine reference charts werehigher than those of the Nellhaus charts at all ages. The values for the 2nd percentile of the national reference were lower than those of the Nellhaus charts during the first 2 years of life, similar between 3 and 7 years of age, and higher after this age. Conclusions. The Argentine curves adequately describe the growth pattern of HC. The differences found with the Nellhaus charts may be attributed to secular changes.

Introducción. El perímetro cefálico (PC) es un indicador del crecimiento cerebral y es necesario contar con referencias de crecimiento que permitan determinar variaciones normales o patológicas. Objetivos. Presentar las primeras referencias argentinas de perímetro cefálico entre el nacimiento y los 19 años, y compararlas con las referencias de Nellhaus, utilizadas en nuestro país hasta la actualidad. Población y métodos. Para la construcción de estas referencias, se combinaron datos de la Encuesta Nacional de Nutrición y Salud 2018 y estudios transversales realizados entre 2004 y 2007 en las provincias de Buenos Aires y La Pampa, que incluyeron 8326 niños, niñas y adolescentes sanos. Las curvas de crecimiento fueron ajustadas con el método LMS. Para evaluar la magnitud de las diferencias entre estas referencias y las de Nellhaus, a diferentes edades, se graficaron los centilos 2, 50 y 98. Resultados. El PC mostró un incremento de tamaño variable con la edad, de mayor magnitud en los primeros años de vida, y un ligero incremento en la pubertad. Los valores del centilo 98 de las referencias argentinas fueron mayores que los de Nellhaus en todas las edades. Los valores del centilo 2 de la referencia nacional fueron menores que los de Nellhaus durante los primeros 2 años de vida, similares entre los 3 y 7 años, y mayores a partir de esta edad. Conclusiones. Las curvas argentinas describen adecuadamente el patrón de crecimiento del PC. Las diferencias halladas con la referencia de Nellhaus pueden atribuirse a cambios seculares.

Trends in weight, height, BMI and obesity in schoolchildren from Santa Rosa (Argentina), 1990-2005/07.

AIM: To assess secular changes in physical growth and the current prevalence and trend of overweight/obesity in Argentinian schoolchildren. SUBJECTS AND METHODS: One thousand and forty-nine schoolchildren aged 6 and 12 years attending schools in 1990 were compared with an age-matched sample of 935 boys and girls collected between 2005-2007. Changes in weight, height and BMI by age between the surveys were analysed using one-way analysis of variance. Overweight and obesity were defined according to IOTF criteria and compared by Chi-squared test. Odds ratios (OR) and intervals of confidence (95% CI) were also calculated. RESULTS: Six and 12 year-old boys and girls were significantly heavier (1.2-3.2 kg) and had higher BMIs (0.7-1.0 kg/m(2)) in 2005-2007 than in 1990. Significant differences in height were seen in 6 year old boys (1.5 cm) and 12 year old girls (1.3 cm). Overweight and obesity increased by 4.4% (OR = 1.4, 1.1-1.8) and 5.9% (OR = 4.3, 2.8-6.5), respectively; obesity being higher in younger children. CONCLUSION: The disharmonic secular change in weight and height has led to high overweight/obesity. The obesity increase is consistent with global and regional trends, indicating a shift in BMI distribution, especially at the higher centiles.

Exploring factors associated with obesity in Argentinian children using structural equation modeling.

Habits and behaviors related to obesity risk are strongly associated with the family environment and are affected by socioeconomic factors. Structural equation modeling (SEM) allows us to hypothesize on how the relationships between these factors occur and measure their impact. This study aimed to explore the relationship between family socioeconomic indicators and childhood obesity, mediated by habits linked to energy balance, applying a SEM. A cross sectional study was performed on 861 Argentinian schoolchildren aged 6-12 years, from 2015 to 2016. The model included three latent variables: socioeconomic status, healthy habits, and obesity. Socioeconomic status indicators and healthy habits were surveyed by self-administered parental questionnaires, whereas obesity indicators were evaluated with anthropometry. The applied model showed an acceptable fit (NFI = 0.966; CFI = 0.979; RMSEA = 0.048). Socioeconomic status positively influenced parental education, health insurance, and car possession, while negatively influenced crowding (p < 0.001). Healthy habits significantly influenced physical activity, meals frequency, and sleep hours, while negatively influenced sedentary hours and mother's nutritional status (p < 0.001). Obesity factor positively influenced body mass index, body fat, and waist-to-height ratio (p < 0.001). Finally, socioeconomic status positively influenced health habits, which in turn negatively influenced obesity factor. Healthy habits (especially physical activity and mother's nutritional status) mediated the relationship between socioeconomic status and child obesity. Further research should include other indicators related to diet, eating habits, and physical activity like neighborhood characteristics.

Prevalence of sleep-disordered breathing among adolescents and its association with the presence of obesity and hypertension. / Prevalencia de trastornos respiratorios del sueño en adolescentes y su relación con la presencia de obesidad e hipertensión arterial.

INTRODUCTION: The increased prevalence of sleepdisordered breathing (SDB) and its association with obesity and hypertension (HTN) have not been thoroughly explored in adolescents. The objective of this study was to investigate the prevalence of SDB and snoring in this population and analyze its association with obesity and HTN. POPULATION AND METHODS: This was a descriptive, cross-sectional study in a sample of adolescents. Weight, height, waist and neck circumference, and blood pressure were measured, and the Pediatric Sleep Questionnaire (PSQ) was administered. RESULTS: A total of 826 adolescents participated, 58 (7%) had SDB (males: 5.8%; females: 8%), and 80 (9.7%) were considered snorers (males: 10.4%; females: 9.1%). Overweight and obesity were detected in 216 (26.2%) and 149 (18%) participants, respectively. A higher proportion of subjects with obesity had SDB compared to those who were not obese (12.8% versus 5.8%; p = 0.004). The same association was observed with snoring (18.2% versus 7.8%; p < 0.001). Also, 24.6% slept less than 8 hours a day and 12.6% had values compatible with HTN, with a significant association with obesity and sleep hours. CONCLUSION: A high prevalence of SDB and snoring was observed in adolescents, together with an association with obesity and HTN, which highlights the relevance of addressing this problem in an early manner in order to prevent complications.

Introducción: El aumento de prevalencia de trastornos respiratorios del sueño (TRS) y su relación con obesidad e hipertensión arterial (HTA) ha sido poco explorado en adolescentes. El objetivo de este estudio fue investigar la prevalencia de TRS y ronquido en esta población y analizar su asociación con obesidad e HTA. Población y métodos: Se realizó un estudio descriptivo de corte transversal en una muestra de adolescentes. Se realizaron mediciones de peso, talla, perímetro de cintura y cuello, tensión arterial, y el Cuestionario de Sueño Pediátrico (PSQ, por su sigla en inglés). Resultados: Participaron 826 adolescentes, 58 (7%) presentaron TRS (varones: 5,8%; mujeres: 8%) y 80 (9,7%) se consideraron roncadores (varones: 10,4%; mujeres: 9,1%). Se detectaron sobrepeso y obesidad en 216 (26,2%) y 149 (18%) sujetos, respectivamente. Una mayor proporción de sujetos con obesidad presentaron TRS con respecto a quienes no tenían obesidad (12,8% versus 5,8%; p = 0,004). La misma asociación fue encontrada para el ronquido (18,2% versus 7,8%;<0,001). El 24,6% dormía menos de 8 horas por día. El 12,6% presentó valores compatibles con HTA, con una asociación significativa con obesidad y horas de sueño. Conclusión: Se observó una prevalencia elevada de TRS y ronquido en adolescentes y una asociación entre obesidad e HTA, que pone de manifiesto la importancia de abordar esta problemática de manera temprana a fin de evitar complicaciones.

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

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.

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.

Physical growth in schoolchildren from Argentina: comparison with Argentinean and CDC/NCHs growth references.

The aim of this study was to assess the physical growth of schoolchildren from Argentina by comparison with the CDC/NCHS and Argentinean growth references (AGR), to contribute to the discussion about the use of local or international references for the assessment of growth in developing countries. Weight and height were measured in 3,411 schoolchildren aged 5-14 years. Data were log-transformed and compared with both references by paired samples t-test (CI = 0.95; alpha = 0.005). The boys' weights were greater than CDC/NCHS (up to 10, and at 14 years old) and the national reference at all ages (P < 0.005). The girls also were heavier than CDC/NCHS (at 7 and 12 years old, P < 0.005) and AGR, except at age 11 and 14 years. In boys, height was lower than CDC/NCHS at 9 and 14 years of age, and higher than AGR at all ages (P < 0.005). The girls were also shorter than CDC/NCHS at 7, 13, and 14 years old (P < 0.005), and-except at age 14-taller than AGR. The weight was higher than both of the references. Height showed a clear dissociation from the national reference and minor differences from CDC/NCHS. Nevertheless, around puberty, the children's height fell short of CDC/NCHS, especially the girls, whose values approached those of their Argentinean peers. This divergence could be associated with cohort effects or population variations in adolescent growth spurt. The use of a single growth reference for preadolescent may be appropriate. The height decrease in adolescents suggests the usefulness of local standards at this period.

Socioenvironmental conditions and nutritional status in urban and rural schoolchildren.

We analyzed the nutritional status of urban and rural schoolchildren from Mendoza (Argentina), but avoided rural and urban categorization by generating subpopulations as a function of their socioenvironmental characteristics. We transformed weight and height data into z-scores using the CDC/NCHS growth charts; defined underweight, stunting, and wasting by z-scores of less than -2 SD; and calculated overweight and obesity, according to the cutoff proposed by the International Obesity Task Force. Socioenvironmental characteristics included housing, public services, parental resources, and farming practices; we processed these variables by categorical principal-component analysis. The two first axes defined four subgroups of schoolchildren: three of these were associated with urban characteristics, while the remaining subgroup was considered rural. Nutritional status differed across groups, whereas overweight was similar among the groups and obesity higher in urban middle-income children. Urban differences were manifested mainly as underweight, but rural children exhibited the greatest stunting and wasting. Thus, the negative effects of environment on nutritional status in children are not restricted to poor periurban and rural areas, though these are indeed unfavorable environments for growth: some urban families provide children with sufficient quantity and diversity of foods to expose them to obesity. By contrast, the more affluent urban families would appear to have greater possibilities for allowing their children to adopt a healthy life-style. Although the causes of differences in nutritional status between middle- and high-income urban groups are not clear, these determinants probably involve economic as well as educational influences.

Exploring factors associated with obesity in Argentinian children using structural equation modeling / Explorando factores asociados a la obesidad en niños argentinos usando un modelo de ecuaciones estructurales / Explorando fatores associados à obesidade em crianças argentinas utilizando a modelagem de equações estruturais

Abstract: Habits and behaviors related to obesity risk are strongly associated with the family environment and are affected by socioeconomic factors. Structural equation modeling (SEM) allows us to hypothesize on how the relationships between these factors occur and measure their impact. This study aimed to explore the relationship between family socioeconomic indicators and childhood obesity, mediated by habits linked to energy balance, applying a SEM. A cross sectional study was performed on 861 Argentinian schoolchildren aged 6-12 years, from 2015 to 2016. The model included three latent variables: socioeconomic status, healthy habits, and obesity. Socioeconomic status indicators and healthy habits were surveyed by self-administered parental questionnaires, whereas obesity indicators were evaluated with anthropometry. The applied model showed an acceptable fit (NFI = 0.966; CFI = 0.979; RMSEA = 0.048). Socioeconomic status positively influenced parental education, health insurance, and car possession, while negatively influenced crowding (p < 0.001). Healthy habits significantly influenced physical activity, meals frequency, and sleep hours, while negatively influenced sedentary hours and mother's nutritional status (p < 0.001). Obesity factor positively influenced body mass index, body fat, and waist-to-height ratio (p < 0.001). Finally, socioeconomic status positively influenced health habits, which in turn negatively influenced obesity factor. Healthy habits (especially physical activity and mother's nutritional status) mediated the relationship between socioeconomic status and child obesity. Further research should include other indicators related to diet, eating habits, and physical activity like neighborhood characteristics.

Resumen: Los hábitos y comportamientos relacionados con el riesgo de obesidad están fuertemente asociados al entorno familiar y se ven afectados por factores socioeconómicos. El modelo de ecuaciones estructurales (MEE) permite plantear hipótesis sobre cómo se dan las relaciones entre estos factores y medir su impacto. El objetivo del presente estudio fue explorar la relación entre los indicadores socioeconómicos familiares y la obesidad infantil, mediada por hábitos relacionados con el balance energético, aplicando un MEE. Se realizó un estudio transversal con 861 escolares argentinos de 6 a 12 años entre 2015 y 2016. El modelo incluyó tres variables latentes: nivel socioeconómico, hábitos saludables y obesidad. Los indicadores nivel socioeconómico y hábitos saludables se midieron mediante cuestionarios autoadministrados a los padres, mientras que los indicadores de obesidad se obtuvieron mediante antropometría. El modelo aplicado presentó un ajuste aceptable (NFI = 0,966; CFI = 0,979; RMSEA = 0,048). El nivel socioeconómico influyó positivamente en la escolaridad de los padres, en el plan de salud y en el hecho de tener automóvil, mientras que influyó negativamente en el hacinamiento (p < 0,001). La variable hábitos saludables influyó significativamente en la actividad física, en la frecuencia de las comidas y en las horas de sueño, pero influyó negativamente en las horas sedentarias y en el estado nutricional materno (p < 0,001). El factor obesidad influyó positivamente en el índice de masa corporal, en la grasa corporal y en la razón cintura/talla (p < 0,001). Finalmente, el nivel socioeconómico influyó positivamente en los hábitos saludables, que, a su vez, influyeron negativamente en la obesidad. Los hábitos saludables, en especial la actividad física y el estado nutricional materno, moderan la relación entre el nivel socioeconómico y la obesidad infantil. Las nuevas investigaciones deberían incluir otros indicadores relacionados con la dieta, con los hábitos alimentarios y con la actividad física, así como con las características del vecindario.

Resumo: Hábitos e comportamentos relacionados ao risco de obesidade estão fortemente associados ao ambiente familiar e afetados por fatores socioeconômicos. A modelagem de equações estruturais (MEE) permite levantar hipóteses sobre como ocorrem as relações entre esses fatores e medir seu impacto. O objetivo do presente estudo foi explorar a relação entre os indicadores socioeconômicos familiares e a obesidade infantil, mediada por hábitos ligados ao balanço energético, aplicando uma MEE. Um estudo transversal foi realizado com 861 escolares argentinos de 6 a 12 anos entre 2015 e 2016. O modelo incluiu três variáveis latentes: nível socioeconômico, hábitos saudáveis e obesidade. Os indicadores do nível socioeconômico e de hábitos saudáveis foram medidos por meio de questionários autoaplicáveis aos pais, enquanto os indicadores de obesidade foram obtidos por meio de antropometria. O modelo aplicado apresentou um ajuste aceitável (NFI = 0,966; CFI = 0,979; RMSEA = 0,048). O nível socioeconômico influenciou positivamente a escolaridade dos pais, o plano de saúde e a posse de automóvel, enquanto influenciou negativamente a aglomeração (p < 0,001). A variável hábitso saudáveis influenciou significativamente a atividade física, a frequência das refeições e as horas de sono, mas influenciou negativamente as horas sedentárias e o estado nutricional materno (p < 0,001). O fator obesidade influenciou positivamente o índice de massa corporal, a gordura corporal e a relação cintura/estatura (p < 0,001). Finalmente, o nível socioeconômico influenciou positivamente os hábitso saudáveis, que por sua vez influenciou negativamente a obesidade. Hábitos saudáveis, especialmente atividade física e estado nutricional materno, mediam a relação entre nível socioeconômico e obesidade infantil. Novas pesquisas devem incluir outros indicadores relacionados à dieta, hábitos alimentares e atividade física, como características da vizinhança.

Argentine references for the assessment of body proportions from birth to 17 years of age. / Referencias argentinas para la evaluación de proporciones corporales desde el nacimiento hasta los 17 años.

INTRODUCTION: Abnormal body proportions may indicate skeletal disorders; therefore, their detection has great clinical significance. OBJETIVES: To estimate centiles for head circumference/height (HC/H) and sitting height/height (SH/H) ratios, and assess their diagnostic usefulness among a group of children with skeletal dysplasia. METHODS: Centiles 3, 10, 25, 50, 75, 90 and 97 for HC/H and SH/H ratios were estimated with the LMS method using Box-Cox transformation to normalize data distribution for each age. Q-Q plot tests were applied to evaluate normality of residuals and the Q test to calculate goodness-of-fit. RESULTS: The sample included 4818 girls and4803 boys, all healthy, between 0-17 years old. The median of the SH/H ratio for each age decreased from 0.67 at birth to 0.57 at age 4. At 12 years of age, values reached 0.52 and 0.53 for males and females, respectively, remaining unchanged until age 17. The median of the HC/H ratio decreased from 0.45 at 6 years old to 0.34 at 17 years old for both sexes. Z-scores for SH/H among 20 children diagnosed with hypochondroplasia were better at showing abnormal proportions than the SH/H ratio not adjusted by age. CONCLUSIONS: Estimated centiles for HC/H and SH/H ratios show that the most dramatic changes in body proportions occur in the prepubertal period. These references allow an earlier detection of abnormal body proportions in children with skeletal dysplasia.

INTRODUCCIÓN: La alteración de las proporciones corporales puede ser indicativa de enfermedad esquelética, por lo cual su detección resulta de gran utilidad clínica. OBJETIVOS: Estimar los centilos de los índices perímetro cefálico/estatura (PC/E) y estatura sentada/estatura (ES/E), y evaluar su utilidad diagnóstica en un grupo de niños con displasia esquelética. MÉTODOS: Los centilos 3, 10, 25, 50, 75, 90 y 97 de ES/E y PC/E fueron estimados por el método LMS, que utiliza la transformación Box-Cox para normalizar la distribución de los datos a cada edad. Se aplicaron los tests Q-Q plot para evaluar la normalidad de los residuos y el Q test para evaluar la bondad de ajuste. RESULTADOS: La muestra incluyó 4818 niñas y 4803 niños sanos de 0 a 17 años de edad. La mediana del índice ES/E para la edad cayó desde valores de 0,67 al nacer hasta 0,57 a los 4 años. A los 12 años, alcanzó valores de 0,52 y 0,53 para varones y mujeres, respectivamente, y se mantuvo así hasta los 17 años de edad. La mediana del índice PC/E cayó desde 0,45 a los 6 años hasta 0,34 a los 17 años de edad en ambos sexos. Los puntajes Z del ES/E en 20 niños con diagnóstico de hipocondroplasia mostraronmejor la desproporción corporal que la utilización del índice ES/E no ajustado por edad. CONCLUSIONES: Los centilos estimados de PC/E y ES/E muestran que, en el período prepuberal, ocurren los mayores cambios en las proporciones corporales. Estas referencias facilitan una detección más temprana de desproporción corporal en niños con displasia esquelética.

Prevalencia de trastornos respiratorios del sueño en adolescentes y su relación con la presencia de obesidad e hipertensión arterial / Prevalence of sleep-disordered breathing among adolescents and its association with the presence of obesity and hypertension

Introducción: El aumento de prevalencia de trastornos respiratorios del sueño (TRS) y su relación con obesidad e hipertensión arterial (HTA) ha sido poco explorado en adolescentes. El objetivo de este estudio fue investigar la prevalencia de TRS y ronquido en esta población y analizar su asociación con obesidad e HTA. Población y métodos: Se realizó un estudio descriptivo de corte transversal en una muestra de adolescentes. Se realizaron mediciones de peso, talla, perímetro de cintura y cuello, tensión arterial, y el Cuestionario de Sueño Pediátrico (PSQ, por su sigla en inglés). Resultados: Participaron 826 adolescentes, 58 (7 %) presentaron TRS (varones: 5,8 %; mujeres: 8 %) y 80 (9,7 %) se consideraron roncadores (varones: 10,4 %; mujeres: 9,1 %). Se detectaron sobrepeso y obesidad en 216 (26,2 %) y 149 (18 %) sujetos, respectivamente. Una mayor proporción de sujetos con obesidad presentaron TRS con respecto a quienes no tenían obesidad (12,8 % versus 5,8 %; p = 0,004). La misma asociación fue encontrada para el ronquido (18,2 % versus 7,8 %; <0,001). El 24,6 % dormía menos de 8 horas por día. El 12,6 % presentó valores compatibles con HTA, con una asociación significativa con obesidad y horas de sueño. Conclusión: Se observó una prevalencia elevada de TRS y ronquido en adolescentes y una asociación entre obesidad e HTA, que pone de manifiesto la importancia de abordar esta problemática de manera temprana a fin de evitar complicaciones

ntroduction: The increased prevalence of sleep-disordered breathing (SDB) and its association with obesity and hypertension (HTN) have not been thoroughly explored in adolescents. The objective of this study was to investigate the prevalence of SDB and snoring in this population and analyze its association with obesity and HTN. Population and methods: This was a descriptive, cross-sectional study in a sample of adolescents. Weight, height, waist and neck circumference, and blood pressure were measured, and the Pediatric Sleep Questionnaire (PSQ) was administered. Results: A total of 826 adolescents participated, 58 (7 %) had SDB (males: 5.8 %; females: 8 %), and 80 (9.7 %) were considered snorers (males: 10.4 %; females: 9.1 %). Overweight and obesity were detected in 216 (26.2 %) and 149 (18 %) participants, respectively. A higher proportion of subjects with obesity had SDB compared to those who were not obese (12.8 % versus 5.8 %; p = 0.004). The same association was observed with snoring (18.2 % versus 7.8 %; p < 0.001). Also, 24.6 % slept less than 8 hours a day and 12.6 % had values compatible with HTN, with a significant association with obesity and sleep hours. Conclusion: A high prevalence of SDB and snoring was observed in adolescents, together with an association with obesity and HTN, which highlights the relevance of addressing this problem in an early manner in order to prevent complications

Catch-up in body weight of intrauterine growth retarded (IUGR) rats castrated and treated with growth hormone.

The aim of the present study was to assess body weight recovery in rats with intrauterine growth retardation (IUGR) castrated and treated with growth hormone (GH). Wistar albino rats were divided into the following experimental groups: control (C), sham-operated (SH), IUGR, IUGR castrated (IUGR+C), and IUGR castrated and injected with GH (IUGR+C+GH). IUGR was induced by partial bending of uterine vessels at day 14 of pregnancy. GH (Genotropin 3.0 mg/kg/day) was administered from weaning (21 days old) to 60 days of age. SH rats were injected only with diluent. Castration was performed at weaning. Body weight, body weight velocity and relative food intake were registered weekly. Data were analyzed by ANOVA and LSD post hoc test. The between-subjects analysis showed significant differences for sex and treatment factors. Differences in body weight were significant among treatments, being SH > IUGR > IUGR+ C+GH > IUGR+C in males, and SH > IUGR+C > IUGR+C+GH > IUGR in females. Differences in relative food intake were IUGR+C > IUGR+C+GH > IUGR > SH in males, and IUGR+C+GH > IUGR+C > IUGR > SH in females. These results indicate that nutritional rehabilitation impairs the effects of IUGR. While the absence of testosterone inhibited body weight gain, the absence of estrogens promoted catch-up growth. Castrated animals with or without GH treatment ate relatively more, suggesting the absence of an anabolic effect of gonadal steroids.

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.

Relative food intake of rats submitted to a moderate transgenerational undernutrition.

An experiment on rat undernutrition through seven generations was performed in order to see: (1) whether the nutritional stress on growth increases from one generation to the next, and (2) if an equilibrium point (AFP) in which the RFI--the amount of food intake (mg) per gram of body weight--reached is the same in both control and undernourished animals. The RFI values were calculated for each generation, between the 30th and 100th days of age. A moderate undernutrition was applied to the seven generations (F1 to F7) following the parental (P) one, which acted as controls. Undernourishment was made from conception to the end of the experiment (100 days old). The RFI values diminished with the age increment and increased through generations. There was, however, a clear AFP of 75.9 +/- 3.5 mg/g at 100 days of age in males, and of 78.7 +/- 4.2 mg/g at 90 days of age in females. A clear cumulative increment of RFI through the filial generations was also found at intermediate growth ages. The frequently argued nongenetic transmission of the nutritional deficiencies from parents to descendants was corroborated with the present results. Such cumulative effect was evident at ages before the AFP was reached; i.e., when the decrement in body mass of the undernourished animals was not yet equilibrated with the amount of available nutrients.