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)

Neonatal anthropometry of malformed newborns: A large South American population-based study.

BACKGROUND: Population-based anthropometric evaluation of malformed newborns is scarce. OBJECTIVES: To evaluate malformed newborns' foetal growth using the ICD 10 malformations' classification. METHODS: A study including 33,769 newborns (14,857 malformed and 18,912 nonmalformed), selected from 678,840 births from nine South American countries, period 2010-2018, was conducted. Prevalence of severe small and small for gestational age was calculated for malformed and nonmalformed newborns classified by preterm birth categories. Prevalence and relative risk (RR) with its 95% confidence interval (CI) were calculated. The associations between anthropometric phenotypes and congenital malformations were evaluated with generalized linear models. RESULTS: Prevalence of preterm and term severe small and small for gestational age newborns was higher in malformed than that in nonmalformed neonates. For grouped ICD 10 malformations categories, the RR for severe small for gestational age was 2.88 (95% CI 2.51, 3.30) and 2.10 (95% CI 1.92, 2.30) for small for gestational age. For at-term and preterm malformed newborns, the RR for severe small for gestational age was 2.21 (95% CI 1.87, 2.61) and 3.21 (95% CI 2.52, 4.10), respectively; for small for gestational age, the RR was 2.31 (95% CI 2.11, 2.53) for at-term newborns and 2.58 (95% CI 2.16, 3.08) for preterm ones. CONCLUSIONS: Prevalence and relative risk of severe small and small for gestational age vary according to the group of malformations and gestational age; they increase in congenital malformations of the nervous, respiratory and digestive systems, and in chromosomal abnormalities and are lower for malformations of eye, ear, face and neck and cleft lip and palate. Foetal growth considered together with malformed newborns' gestational age would allow for inferring different risks of morbidity and mortality.

Surnames and population structure in the Doctrine of Belén, Altos de Arica, Viceroyalty of Peru (1750-1813).

The analysis of multiple population structures (biodemographic, genetic and socio-cultural) and their inter-relations contribute to a deeper understanding of population structure and population dynamics. Genetically, the population structure corresponds to the deviation of random mating conditioned by a limited number of ancestors, by restricted migration in the social or geographic space, or by preference for certain consanguineous unions. Through the isonymic method, surname frequency and distribution across the population can supply quantitative information on the structure of a human population, as they constitute universal socio-cultural variables. Using documentary sources to undertake the Doctrine of Belén's (Altos de Arica, Chile) historical demography reconstruction between 1763 and 1820, this study identified an indigenous population with stable patronymics. The availability of complete marriage, baptism and death records, low rates of migration and the significant percentage of individuals registered and constantly present in this population favoured the application of the isonymic method. The aim of this work was to use given names and surnames recorded in these documentary sources to reconstruct the population structure and migration pattern of the Doctrine of Belén between 1750 and 1813 through the isonymic method. The results of the study were consistent with the ethno-historical data of this ethnic space, where social cohesion was, in multiple ways, related to the regulation of daily life in colonial Andean societies.

Excess weight and thinness over two decades (1996-2015) and spatial distribution in children from Jujuy, Argentina.

BACKGROUND: The increase of excess weight around the world is progressive and sustained in children. This is the most prevalent form of malnutrition in this population and they represent the major public health problem in developed and developing countries. The aim of this study was to analyze the magnitude of change in thinness and excess weight prevalence in 4-7 years-old schoolchildren from Jujuy (Argentina), between 1996 and 2015 and to examine the association according to sex and school location. METHODS: Cross-sectional study. Data was obtained from databases of School Health programs and it is representative of the city school population. For the analysis, 31,014 schoolchildren between 4 and 7 years old were evaluated, 20,224 from the first period (1996-2001) and 10,790 from the second (2010-2015). The city was partitioned in three different areas determined by the rivers that cross it. Nutritional status was determined by BMI for age with the criteria suggested by the International Obesity Task Force. The percentage of malnutrition change between periods was calculated and a binomial regression model was adjusted. RESULTS: Between periods, a significant (p-value< 0.0001) increase in the prevalence of overweight from 15.1% (CI 14.6-15.6%) to 18.1% (CI 17.4-18.8%) and obesity from 5% (CI 4.7-5.3) to 10.7% (CI 10.1-11.3%), and a decrease of thinness prevalence from 6.3% (CI 6.0-6.7%) to 4.7% (CI 4.3-5.1%) were observed. The percentage of change in the prevalence of obesity was very high in all areas and in both sexes (103.5% girls; 125.6% in boys), being higher in the south for girls (122.4%) and in the north for boys (158.8%). Besides, being a boy was inversely associated with the presence of excess weight and, as the age increases, the presence of obesity does it too. By analyzing the effect of the school location, the south and north zones had an inverse association with the presence of obesity. The period has a direct association with the presence of excess weight. CONCLUSION: The study contributes with valuable information on the magnitude of the increase in obesity in schoolchildren and suggests a possible correlation with sex and spatial distribution in the capital city of Jujuy.

Proportionality indices, geographic altitude, and gestational age in newborns from Jujuy, Argentina.

BACKGROUND: There are several different proportionality indices (PRIs) to evaluate size at birth by gestational age (GA). Yet, the explanatory power of alternative PRIs has not been evaluated in highland (HL) populations. AIM: Evaluate the relative utility of three PRIs, weight to length ratio (W/L), body mass index (BMI), and ponderal index (PI), for assessing nutritional status in newborns (NBs) from highland (HL ≥ 2000 m) and lowland (LL < 2000 m) regions of the Jujuy Province of Argentina. SUBJECTS AND METHODS: Births were registered by the Ministry of Health (Jujuy, 2009-2014). Data were grouped according to HL and LL altitude groups based on of maternal residence. The main outcome measures were the PRIs W/L ratio, BMI, and PI. Percentiles were generated by the LMS method and compared with references. ANOVAs and Pearson correlations were used to examine the relationship between outcome measures with weight and length by altitude, sex, and GA. RESULTS: In both altitude zones, W/L and BMI increased with GA, while PI stabilized between 37th and 42th weeks. The LL sample had significantly higher values for all the PRIs from the 37th week of GA. In the HL sample, the 50th percentiles for all three PRIs were lower than the reference. Regardless of GA and altitude level, BMI showed the lowest correlation with length and the higher with the weight. CONCLUSION: The HL sample of term NBs had lower values for all PRIs compared to their LL counterparts. In both altitude zones, the BMI is the preferred PRI to evaluate the nutritional status.

Fine-scale genomic analyses of admixed individuals reveal unrecognized genetic ancestry components in Argentina.

Similarly to other populations across the Americas, Argentinean populations trace back their genetic ancestry into African, European and Native American ancestors, reflecting a complex demographic history with multiple migration and admixture events in pre- and post-colonial times. However, little is known about the sub-continental origins of these three main ancestries. We present new high-throughput genotyping data for 87 admixed individuals across Argentina. This data was combined to previously published data for admixed individuals in the region and then compared to different reference panels specifically built to perform population structure analyses at a sub-continental level. Concerning the Native American ancestry, we could identify four Native American components segregating in modern Argentinean populations. Three of them are also found in modern South American populations and are specifically represented in Central Andes, Central Chile/Patagonia, and Subtropical and Tropical Forests geographic areas. The fourth component might be specific to the Central Western region of Argentina, and it is not well represented in any genomic data from the literature. As for the European and African ancestries, we confirmed previous results about origins from Southern Europe, Western and Central Western Africa, and we provide evidences for the presence of Northern European and Eastern African ancestries.

Dyslipidemia in schoolchildren with excess weight from Jujuy assessed by the program of school health / [Dislipemias en escolares jujeños con exceso de peso evaluados por el programa de salud escolar.]

Background: Excess weight (EW) and alterations in lipid metabolism constitute risk factors for cardiovascular disease in adults and children. Prevalence of dyslipidemia in schoolchildren from Jujuy with EW is analyzed in this study. Methods: Cross-sectional descriptive study of 891 schoolchildren 10-14 years old (367 girls; 524 boys) from the province of Jujuy (Northwestern Argentina). Prevalence of dyslipidemia for Overweight (OW) and Obesity (OB) were calculated, according to the International Obesity Task Force cut-off points. Prevalence of lipid alterations were analyzed and 7 dyslipidemic profiles were established. Comparisons and associations between variables were analyzed by Chi-square test. Crude and adjusted odds ratio were estimated from a logistic regressions. Results: Regardless of sex and nutritional status, 13.7%, 21.8%, and 16.5% of schoolchildren showed high values of total cholesterol, triglycerides, and LDL cholesterol, respectively, and 20.3% had low HDL cholesterol. Significantly higher values of HDL cholesterol were found in OW, and of triglycerides in OB. A significant association was recorded between OB and high triglycerides. Schoolchildren with OB have a 54% more chances of showing at least one lipid alteration. Conclusion: EW, and especially OB, constitutes an important risk factor in the development of dyslipidemia in schoolchildren from Jujuy.

Introducción: El exceso de peso (EP) y las alteraciones del metabolismo lipídico constituyen factores de riesgo de enfermedad cardiovascular en adultos y en niños. En este estudio se analiza la prevalencia de dislipemias en escolares jujeños con EP. Población y métodos: Estudio descriptivo, de corte transversal de 891 escolares entre 10-14 años (367 mujeres; 524 varones) de la provincia de Jujuy (Noroeste de Argentina). Se calcularon las prevalencias de dislipemias para Sobrepeso (SP) y Obesidad (OB), determinados según puntos de corte de la International Obesity Task Force. Se analizaron las prevalencias de alteraciones lipídicas y se establecieron 7 perfiles dislipemicos. Las comparaciones y asociaciones entre variables se analizaron con Chi cuadrado. Se estimaron odds ratio crudos y ajustados a partir de una regresión logística. Resultados: Independientemente del sexo y del estado nutricional el 13.7%, 21.8% y 16.5% de los escolares presentaron colesterol total, triglicéridos y colesterol LDL alto, respectivamente y el 20.3% colesterol HDL bajo. Se observaron valores significativamente más elevados de colesterol HDL en SP y de triglicéridos en OB. Se registró asociación significativa entre OB y triglicéridos altos. Los escolares con OB exhiben 54% más de chances de presentar al menos una alteración lipídica.. Conclusión: El EP, y sobre todo la OB, constituye un factor de riesgo importante para el desarrollo de dislipemias en escolares jujeños

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.

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.

Geographic altitude and prevalence of underweight, stunting and wasting in newborns with the INTERGROWTH-21st standard / Altitude geográfica e prevalência de recém-nascidos abaixo do peso, com baixa estatura e emaciação de acordo com o padrão INTERGROWTH-21st

Abstract Objective: To assess the prevalence and risks of underweight, stunting and wasting by gestational age in newborns of the Jujuy Province, Argentina at different altitude levels. Methods: Live newborns (n = 48,656) born from 2009-2014 in public facilities with a gestational age between 24+0 to 42+6 weeks. Phenotypes of underweight (<P3 weight/age), stunting (<P3 length/age) and wasting (<P3 body mass index/age) were calculated using Intergrowth-21st standards. Risk factors were maternal age, education, body mass index, parity, diabetes, hypertension, preeclampsia, tuberculosis, prematurity, and congenital malformations. Data were grouped by the geographic altitude: ≥2.000 or <2.000 m.a.s.l. Chi-squared test and a multivariate logistic regression analysis were performed to estimate the risk of the phenotypes associated with an altitudinal level ≥2.000 m.a.s.l. Results: The prevalence of underweight, stunting and wasting were 1.27%, 3.39% and 4.68%, respectively, and significantly higher at >2.000 m.a.s.l. Maternal age, body mass index >35 kg/m2, hypertension, congenital malformations, and prematurity were more strongly associated with underweight rather than stunting or wasting at ≥2.000 m.a.s.l. Conclusions: Underweight, stunting, and wasting risks were higher at a higher altitude, and were associated with recognized maternal and fetal conditions. The use of those three phenotypes will help prioritize preventive interventions and focus the management of fetal undernutrition.

Resumo Objetivo: Avaliar a prevalência e os riscos de recém-nascidos abaixo do peso, baixa estatura e emaciação por idade gestacional da Província de Jujuy, Argentina, em diferentes níveis de altitude. Métodos: Recém-nascidos vivos (n = 48.656) nascidos entre 2009 e 2014 em instalações públicas entre 24+0-42+6 semanas de idade gestacional. Os fenótipos de abaixo do peso (< P3 peso/idade), baixa estatura (< P3 comprimento/idade) e emaciação (< P3 índice de massa corporal/idade) foram calculados com os padrões do INTERGROWTH-21st. Os fatores de risco foram idade materna, escolaridade, índice de massa corporal, paridade, diabetes, hipertensão, pré-eclâmpsia, tuberculose, prematuridade e malformações congênitas. Os dados foram agrupados pela altitude geográfica: ≥ 2.000 ou < 2.000 m.a.s.l. O teste qui-quadrado e a análise de regressão logística multivariada foram feitos para estimar o risco dos fenótipos associados ao nível de altitude ≥ 2.000 m.a.s.l. Resultados: A prevalência de abaixo do peso, baixa estatura e emaciação foi de 1,27%, 3,39% e 4,68%, respectivamente, significativamente maiores em > 2.000 m.a.s.l. A idade materna, índice de massa corporal > 35 kg/m2, hipertensão, malformações congênitas e prematuridade foram mais fortemente associados a abaixo do peso e não a baixa estatura ou emaciação em ≥ 2.000 m.a.s.l. Conclusões: Os riscos de abaixo do peso, baixa estatura e emaciação foram maiores em altitude mais elevada e foram associados a condições maternas e fetais reconhecidas. O uso desses três fenótipos ajudará a priorizar as intervenções preventivas e focar no manejo da desnutrição fetal.

Epidemiología de las muertes súbitas infantiles inesperadas en Argentina: tendencia secular y variación espacial / Epidemiology of sudden unexpected death in infancy in Argentina: secular trend and spatial variation

Introducción. La mortalidad infantil incluye defunciones de menores de un año. La proporción de muerte súbita inesperada infantil (MSII) varía entre países y según las causas de muerte consideradas. Objetivo. Describir la variación espacial y temporal de MSII en Argentina entre 1991 y 2014 utilizando la Clasificación Internacional de Enfermedades, décima revisión. Materiales y métodos. A partir de la información de defunciones infantiles (Dirección de Estadísticas e Información de Salud), se calculó el porcentaje de MSII sobre el total de muertes infantiles y la frecuencia de las causas que la componían a nivel nacional, regional y provincial. El riesgo de muerte y la tendencia secular se calcularon con regresión de Poisson. Para detectar agrupamientos departamentales con porcentajes de MSII significativamente diferentes a los nacionales, se utilizó el programa SaTScan v9.1.1. Resultados. En Argentina, entre 1991 y 2014, fallecieron 267 552 menores de un año; el 7 % fueron MSII; la tendencia secular de estas causas fue negativa y estadísticamente significativa; el riesgo de MSII fue de 0,86, y se observó una gran heterogeneidad espacial. A nivel nacional, la causa más frecuente fue síndrome de la muerte súbita del lactante, con diferencias interregionales. Nueve agrupamientos departamentales tuvieron riesgo de MSII entre 4,36 y 1,24, significativamente diferentes al resto del país. Conclusiones. La proporción de MSII y de las causas que la componen presenta heterogeneidad interregional con predominio de códigos relacionados con diagnósticos imprecisos en las regiones más desfavorecidas y de síndrome de muerte súbita del lactante en las más desarrolladas.

Introduction. Infant mortality comprises deaths among infants younger than one year old. The proportion of sudden unexpected death in infancy (SUDI) varies by country and based on the cause of death. Objective. To describe the spatial and temporal variation of SUDI in Argentina between 1991 and 2014 according to the International Classification of Diseases, tenth revision. Materials and methods. Based on infant death data (provided by the Health Statistics and Information Department), we estimated the percentage of SUDI over the total number of infant deaths and the frequency of causes of death at a provincial, regional, and national level. The risk for death and the secular trend were estimated using a Poisson regression. The SaTScan software, v9.1.1, was used to detect clusters of districts where the percentage of SUDI was significantly different from the national percentage. Results. In Argentina, between 1991 and 2014, 267 552 infants younger than 1 year died; 7 % corresponded to SUDI; the secular trend of causes was negative and statistically significant; the risk for SUDI was 0.86, and a great spatial heterogeneity was observed. At a national level, the most common cause was sudden infant death syndrome, with inter-regional differences. In nine district clusters, the risk for SUDI ranged between 4.36 and 1.24, which is significantly different from the rest of the country. Conclusions. The proportion of SUDI and its causes show inter-regional heterogeneity; codes related to inaccurate diagnoses predominated in more unfavorable regions, while sudden infant death syndrome was prevalent in the more developed regions.

Epidemiology of sudden unexpected death in infancy in Argentina: secular trend and spatial variation. / Epidemiología de las muertes súbitas infantiles inesperadas en Argentina: tendencia secular y variación espacial.

Introduction: Infant mortality comprises deaths among infants younger than one year old. The proportion of sudden unexpected death in infancy (SUDI) varies by country and based on the cause of death. Objective: To describe the spatial and temporal variation of SUDI in Argentina between 1991 and 2014 according to the International Classification of Diseases, tenth revision. Materials and methods: Based on infant death data (provided by the Health Statistics and Information Department), we estimated the percentage of SUDI over the total number of infant deaths and the frequency of causes of death at a provincial, regional, and national level. The risk for death and the secular trend were estimated using a Poisson regression. The SaTScan software, v9.1.1, was used to detect clusters of districts where the percentage of SUDI was significantly different from the national percentage. Results: In Argentina, between 1991 and 2014, 267 552 infants younger than 1 year died; 7 % corresponded to SUDI; the secular trend of causes was negative and statistically significant; the risk for SUDI was 0.86, and a great spatial heterogeneity was observed. At a national level, the most common cause was sudden infant death syndrome, with inter-regional differences. In nine district clusters, the risk for SUDI ranged between 4.36 and 1.24, which is significantly different from the rest of the country. Conclusions: The proportion of SUDI and its causes show inter-regional heterogeneity; codes related to inaccurate diagnoses predominated in more unfavorable regions, while sudden infant death syndrome was prevalent in the more developed regions.

Introducción. La mortalidad infantil incluye defunciones de menores de un año. La proporción de muerte súbita inesperada infantil (MSII) varía entre países y según las causas de muerte consideradas. Objetivo. Describir la variación espacial y temporal de MSII en Argentina entre 1991 y 2014 utilizando la Clasificación Internacional de Enfermedades, décima revisión. Materiales y métodos. A partir de la información de defunciones infantiles (Dirección de Estadísticas e Información de Salud), se calculó el porcentaje de MSII sobre el total de muertes infantiles y la frecuencia de las causas que la componían a nivel nacional, regional y provincial. El riesgo de muerte y la tendencia secular se calcularon con regresión de Poisson. Para detectar agrupamientos departamentales con porcentajes de MSII significativamente diferentes a los nacionales, se utilizó el programa SaTScan v9.1.1. Resultados. En Argentina, entre 1991 y 2014, fallecieron 267 552 menores de un año; el 7 % fueron MSII; la tendencia secular de estas causas fue negativa y estadísticamente significativa; el riesgo de MSII fue de 0,86, y se observó una gran heterogeneidad espacial. A nivel nacional, la causa más frecuente fue síndrome de la muerte súbita del lactante, con diferencias interregionales. Nueve agrupamientos departamentales tuvieron riesgo de MSII entre 4,36 y 1,24, significativamente diferentes al resto del país. Conclusiones. La proporción de MSII y de las causas que la componen presenta heterogeneidad interregional con predominio de códigos relacionados con diagnósticos imprecisos en las regiones más desfavorecidas y de síndrome de muerte súbita del lactante en las más desarrolladas.

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.

Geographic altitude and prevalence of underweight, stunting and wasting in newborns with the INTERGROWTH-21st standard.

OBJECTIVE: To assess the prevalence and risks of underweight, stunting and wasting by gestational age in newborns of the Jujuy Province, Argentina at different altitude levels. METHODS: Live newborns (n=48,656) born from 2009-2014 in public facilities with a gestational age between 24+0 to 42+6 weeks. Phenotypes of underweight (2.000m.a.s.l. Maternal age, body mass index >35kg/m2, hypertension, congenital malformations, and prematurity were more strongly associated with underweight rather than stunting or wasting at ≥2.000m.a.s.l. CONCLUSIONS: Underweight, stunting, and wasting risks were higher at a higher altitude, and were associated with recognized maternal and fetal conditions. The use of those three phenotypes will help prioritize preventive interventions and focus the management of fetal undernutrition.

Population structure in Argentina.

We analyzed 391 samples from 12 Argentinian populations from the Center-West, East and North-West regions with the Illumina Human Exome Beadchip v1.0 (HumanExome-12v1-A). We did Principal Components analysis to infer patterns of populational divergence and migrations. We identified proportions and patterns of European, African and Native American ancestry and found a correlation between distance to Buenos Aires and proportion of Native American ancestry, where the highest proportion corresponds to the Northernmost populations, which is also the furthest from the Argentinian capital. Most of the European sources are from a South European origin, matching historical records, and we see two different Native American components, one that spreads all over Argentina and another specifically Andean. The highest percentages of African ancestry were in the Center West of Argentina, where the old trade routes took the slaves from Buenos Aires to Chile and Peru. Subcontinentaly, sources of this African component are represented by both West Africa and groups influenced by the Bantu expansion, the second slightly higher than the first, unlike North America and the Caribbean, where the main source is West Africa. This is reasonable, considering that a large proportion of the ships arriving at the Southern Hemisphere came from Mozambique, Loango and Angola.

Prevalencias de bajo peso y pequeño para la edad gestacional en Argentina: comparación entre el estándar INTERGROWTH-21st y una referencia argentina / Prevalence of low weight and small for gestational age in Argentina: Comparison between the INTERGROWTH-21st standard and an Argentine reference

Introducción. Bajo peso al nacer (< 2500 g) incluye recién nacidos pretérmino y a término pequeños para la edad gestacional (PEG) (< P10). La Organización Mundial de la Salud define bajo peso (BP) como peso al nacer < P3 peso/edad. Internacionalmente, no existe consenso sobre estándares y/o referencias de peso al nacer por edad gestacional (EG) para evaluar PEG y BP en pretérminos. Se determinó la prevalencia de BP y PEG con el estándar INTERGROWTH-21st y la referencia poblacional argentina de Urquía, y se analizó la concordancia de las prevalencias entre ambas herramientas. Población y métodos. Estudio observacional, analítico y retrospectivo realizado sobre los nacimientos registrados en 2013 en el Ministerio de Salud de la Nación. Los criterios de exclusión fueron EG < 24+0 -> 42+6 semanas, embarazo gemelar y ausencia de datos de peso, EG y sexo. Se calcularon las prevalencias por sexo, regiones y categorías de prematurez de BP y PEG con el estándar y la referencia. La concordancia se evaluó con Kappa. Resultados. Las prevalencias de BP y PEG fueron más altas con el estándar en pretérmino; lo contrario se observó en recién nacidos a término. La significación estadística varió según categorías de EG, sexo y regiones. Las prevalencias más altas se presentaron en regiones del norte argentino y las concordancias entre prevalencias oscilaron entre débiles y muy buenas. Conclusiones. Las concordancias de prevalencias de BP y PEG obtenidas con el estándar y la referencia en pretérmino y a término fueron moderadas, y se observó variabilidad interregional. Los resultados plantean nuevas perspectivas auxológicas en la evaluación epidemiológica del retardo del crecimiento intrauterino en Argentina.

Introduction. The term "low birth weight" (< 2500 g) encompasses preterm newborns and term newborns small for gestational age (SGA) (< P10). The World Health Organization defines low weight (LW) as a birth weight < P3 of weight/age. There is no consensus at an international level about which standards and/or references related to birth weight for gestational age (GA) should be used to assess SGA and LW among preterm newborns. LW and SGA prevalence was determined using the INTERGROWTH-21st standard and Urquia's reference for the Argentine population, and agreement between the prevalence observed with both tools was analyzed. Population and methods. Observational, analytical, and retrospective study based on all births occurred in 2013 as reported by the Argentine National Ministry of Health. Exclusion criteria were GA < 24+0 - > 42+6 weeks, twin pregnancy, and missing data on weight, GA, and sex. Prevalence was estimated by sex, region, and prematurity category for LW and SGA according to the standard and the reference. Agreement was assessed using the Kappa index. Results. The prevalence of LW and SGA was higher according to the standard among preterm newborns; the contrary was observed among full-term newborns. Statistical significance varied based on GA category, sex, and region. A higher prevalence was observed in the northern regions of Argentina, and agreement among prevalence values ranged from weak to very good. Conclusions. Prevalence agreement of LW and SGA observed according to the standard and the reference among preterm and full-term newborn infants was moderate, with interregional variability. Results propose new auxological perspectives in the epidemiological assessment of intrauterine growth restriction in Argentina.

Prevalence of underweight and small for gestational age in Argentina: Comparison between the INTERGROWTH-21st standard and an Argentine reference / Prevalencias de bajo peso y pequeño para la edad gestacional en Argentina: comparación entre el estándar INTERGROWTH-21st y una referencia argentina

INTRODUCTION: The term "low birth weight" (< 2500 g) encompasses preterm newborns and term newborns small for gestational age (SGA) (< P10). The World Health Organization de nes underweight as a birth weight < P3 of weight/ age. There is no consensus at an international level about which standards and/or references related to birth weight for gestational age (GA) should be used to assess SGA and underweight among preterm newborns. Underweight and SGA prevalence was determined using the INTERGROWTH-21st standard and Urquía's reference for the Argentine population, and agreement between the prevalence observed with both tools was analyzed. POPULATION AND METHODS: Observational, analytical, and retrospective study based on all births occurred in 2013 as reported by the Argentine National Ministry of Health. Exclusion criteria were GA < 24+0 - > 42+6 weeks, twin pregnancy, and missing data on weight, GA, and sex. Prevalence was estimated by sex, region, and prematurity category for underweight and SGA according to the standard and the reference. Agreement was assessed using the Kappa index. RESULTS: The prevalence of underweight and SGA was higher according to the standard among preterm newborns; the contrary was observed among full-term newborns. Statistical signi cance varied based on GA category, sex, and region. A higher prevalence was observed in the northern regions of Argentina, and agreement among prevalence values ranged from weak to very good. CONCLUSIONS: Prevalence agreement of underweight and SGA observed according to the standard and the reference among preterm and full-term newborn infants was moderate, with interregional variability. Results propose new auxological perspectives in the epidemiological assessment of intrauterine growth restriction in Argentina.

INTRODUCCIÓN: Bajo peso al nacer (< 2500 g) incluye recién nacidos pretérmino y a término pequeños para la edad gestacional (PEG) (< P10). La Organización Mundial de la Salud de ne bajo peso (BP) como peso al nacer < P3 peso/edad. Internacionalmente, no existe consenso sobre estándares y/o referencias de peso al nacer por edad gestacional (EG) para evaluar PEG y BP en pretérminos. Se determinó la prevalencia de BP y PEG con el estándar INTERGROWTH-21st y la referencia poblacional argentina de Urquía, y se analizó la concordancia de las prevalencias entre ambas herramientas. POBLACIÓN Y MÉTODOS: Estudio observacional, analítico y retrospectivo realizado sobre los nacimientos registrados en 2013 en el Ministerio de Salud de la Nación. Los criterios de exclusión fueron EG < 24+0-> 42+6 semanas, embarazo gemelar y ausencia de datos de peso, EG y sexo. Se calcularon las prevalencias por sexo, regiones y categorías de prematurez de BP y PEG con el estándar y la referencia. La concordancia se evaluó con Kappa. RESULTADOS: Las prevalencias de BP y PEG fueron más altas con el estándar en pretérmino; lo contrario se observó en recién nacidos a término. La signi cación estadística varió según categorías de EG, sexo y regiones. Las prevalencias más altas se presentaron en regiones del norte argentino y las concordancias entre prevalencias oscilaron entre débiles y muy buenas. CONCLUSIONES: Las concordancias de prevalencias de BP y PEG obtenidas con el estándar y la referencia en pretérmino y a término fueron moderadas, y se observó variabilidad interregional. Los resultados plantean nuevas perspectivas auxológicas en la evaluación epidemiológica del retardo del crecimiento intrauterino en Argentina.

Relación de la mortalidad infantil con la altura geográfica en el Noroeste Argentino / Relationship between infant mortality and altitude in the Northwest region of Argentina

Introducción. Por su localización sobre los Andes, el Noroeste Argentino presenta una heterogeneidad geográfica, socioeconómica, cultural y biológica reflejada en tasas de mortalidad infantil (TMI) superiores a casi todas las regiones argentinas. Objetivo. Calcular la TMI, tasa de mortalidad neonatal (TMN) y la tasa de mortalidad posneonatal (TMP) para analizar su variación temporal y espacial, a través de la tendencia secular y el riesgo relativo de acuerdo con el nivel altitudinal. Población y método. En un estudio retrospectivo, descriptivo y de correlación basado en datos de nacimientos y defunciones infantiles sucedidos en el Noroeste Argentino (1998-2010), se calcularon por departamentos y nivel altitudinal (departamentos a < 2000metros sobre el nivel del mar, tierras bajas y > 2000 msnm, tierras altas) TMI, TMN y TMP, tendencia secular y riesgo relativo de muerte, realizando un análisis de agrupamiento. Resultados y conclusiones. Las tasas fueron más elevadas en tierras altas, la TMI fue de 29,8%o (en tierras bajas, 15,6%); la TMP en tierras altas fue de 17,7% y 5,2% en tierras bajas. Las tierras altas mostraron un descenso promedio anual del 3,9% para la TMI y del 4,1% para la TMP; en tierras bajas, el descenso fue de 7,0% para la TMI y del 9,3% para la TMP. El riesgo relativo fue significativamente mayor a grandes alturas para TMI y TMP. La TMN, su tendencia secular y riesgo relativo no mostraron diferencias estadísticamente significativas entre niveles de altura.

Introduction. Given its location on the Andes, the Northwest region of Argentina is geographically, socioeconomically, culturally, and biologically heterogeneous, and this is reflected on an infant mortality rate (IMR) that is higher than in any other Argentine region. Objective. To estimate IMR, neonatal mortality rate (NMR), and post-neonatal mortality rate (PNMR), and to analyze their spatial and temporal variations using secular trends and the relative risk based on altitudinal zones. Population and method. This was a retrospective, descriptive, correlational study based on birth and death data recorded in the Northwest region of Argentina (1998-2010); IMR, NMR, PNMR, secular trends, and the relative risk of death were calculated by district and altitudinal zone (districts at < 2000 meters above sea level, lowlands; at > 2000 meters above sea level, highlands) by means of a cluster analysis. Results and conclusions. Rates were higher in the highlands; IMR was 29.8%o (versus 15.6%o in the lowlands); PNMR was 17.7% in the highlands (versus 5.2% in the lowlands). In the highlands, there was an annual average reduction of 3.9% in IMR and of 4.1% in PNMR; in the lowlands, such reduction was of 7.0% in IMR and of 9.3% in PNMR. The relative risk of IMR and PNMR was significantly higher at high-altitude zones. NMR, its secular trend, and the relative risk did not show statistically significant differences between both altitudinal zones.

Relationship between infant mortality and altitude in the Northwest region of Argentina. / Relación de la mortalidad infantil con la altura geográfica en el Noroeste Argentino.

INTRODUCTION: Given its location on the Andes, the Northwest region of Argentina is geographically, socioeconomically, culturally, and biologically heterogeneous, and this is reflected on an infant mortality rate (IMR) that is higher than in any other Argentine region. OBJETIVE: To estimate IMR, neonatal mortality rate (NMR), and post-neonatal mortality rate (PNMR), and to analyze their spatial and temporal variations using secular trends and the relative risk based on altitudinal zones. POPULATION AND METHOD: This was a retrospective, descriptive, correlational study based on birth and death data recorded in the Northwest region of Argentina (1998-2010); IMR, NMR, PNMR, secular trends, and the relative risk of death were calculated by district and altitudinal zone (districts at < 2000 meters above sea level, lowlands; at > 2000 meters above sea level, highlands) by means of a cluster analysis. RESULTS AND CONCLUSIONS: Rates were higher in the highlands; IMR was 29.8%o (versus 15.6%o in the lowlands); PNMR was 17.7% in the highlands (versus 5.2% in the lowlands). In the highlands, there was an annual average reduction of 3.9% in IMR and of 4.1% in PNMR; in the lowlands, such reduction was of 7.0% in IMR and of 9.3% in PNMR. The relative risk of IMR and PNMR was significantly higher at high-altitude zones. NMR, its secular trend, and the relative risk did not show statistically significant differences between both altitudinal zones.

INTRODUCCIÓN: Por su localización sobre los Andes, el Noroeste Argentino presenta una heterogeneidad geográfica, socioeconómica, cultural y biológica reflejada en tasas de mortalidad infantil (TMI) superiores a casi todas las regiones argentinas. OBJETIVO: Calcular la TMI, tasa de mortalidad neonatal (TMN) y la tasa de mortalidad posneonatal (TMP) para analizar su variación temporal y espacial, a través de la tendencia secular y el riesgo relativo de acuerdo con el nivel altitudinal. POBLACIÓN Y MÉTODO: En un estudio retrospectivo, descriptivo y de correlación basado en datos de nacimientos y defunciones infantiles sucedidos en el Noroeste Argentino (1998-2010), se calcularon por departamentos y nivel altitudinal (departamentos a < 2000metros sobre el nivel del mar, tierras bajas y > 2000 msnm, tierras altas) TMI, TMN y TMP, tendencia secular y riesgo relativo de muerte, realizando un análisis de agrupamiento. RESULTADOS Y CONCLUSIONES: Las tasas fueron más elevadas en tierras altas, la TMI fue de 29,8%o (en tierras bajas, 15,6%); la TMP en tierras altas fue de 17,7% y 5,2% en tierras bajas. Las tierras altas mostraron un descenso promedio anual del 3,9% para la TMI y del 4,1% para la TMP; en tierras bajas, el descenso fue de 7,0% para la TMI y del 9,3% para la TMP. El riesgo relativo fue significativamente mayor a grandes alturas para TMI y TMP. La TMN, su tendencia secular y riesgo relativo no mostraron diferencias estadísticamente significativas entre niveles de altura.

CONSANGUINITY BY RANDOM ISONYMY AND SOCIOECONOMIC DEVELOPMENT IN ARGENTINA: A POPULATION STUDY.

In human populations various flexible, labile and interdependent structures (genetic, demographic, socioeconomic) co-exist, each of which can be organized in an hierarchical order corresponding to administrative entities. The relationship between consanguinity, as estimated by random isonymy (F ST), and socioeconomic conditions was analysed at different levels of political and administrative organization in Argentina. From the surnames of 22,666,139 voters from the 2001 electoral roll, F ST was estimated for 510 Argentinian departments. Using a principal component analysis, a Socio-Demographic and Economic Indicator (SDEI), summarizing the effect of 22 socioeconomic and demographic variables at the departmental level, was computed. The relationship between departmental F ST and SDEI values was analysed for the whole nation and within regions using multiple regression analysis. The F ST presented a clinal distribution with the highest values in the north and west of the country, while SDEI expressed the opposite behaviour. A negative and significant correlation was observed between F ST and SDEI, accounting for 46% of the variation in consanguinity in Argentina. The strongest correlations of F ST with SDEI were observed in the Central, Patagonia and Cuyo regions, i.e. those with the highest values of SDEI and lowest values of F ST.