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)

Mortalidad infantil por malformaciones congénitas en Chile: análisis temporal y espacial, 1997-2011 / Infant mortality from congenital malformations in Chile: temporal and spatial analysis, 1997-2011

OBJETIVO:Analizar la distribución espacial y temporal (1997-2011) de la mortalidad infantil por malformaciones congénitas (MC) en Chile. MÉTODOS: Los datos de nacimientos y muertes en menores de 1 año de edad codificados con la CIE-10 se obtuvieron del Instituto Nacional de Estadísticas. Para las regiones administrativas y las naturales (Norte Grande, Norte Chico, Central, Austral y Sur), sistemas (nervioso, cardiovascular, digestivo, genitourinario, musculo esquelético, anomalías cromosómicas) y 28 malformaciones específicas, se estimaron el porcentaje de muertes por MC (PM-MC) y la tasa de mortalidad infantil por MC (TMI-MC) en 3 períodos (1997-2001, 2002-2009, 2007-2011). La tendencia secular y la variación del riesgo de muerte se estimaron con un modelo de regresión de Poisson. RESULTADOS: Para todo Chile, la tendencia secular de la TMI-MC y el PM-MC fueron negativa y positiva, respectivamente (P < 0,01). La TMI-MC y el PM-MC exhibieron una heterogeneidad espacial discreta en las regiones administrativas y naturales. La región natural que más se acercó al patrón nacional fue la Central. La tendencia secular de la TMI-MC de los sistemas nervioso y cardíaco y de algunas MC específicas (anencefalia, espina bífida, y comunicaciones interauricular e interventricular) fue negativa. El patrón de mortalidad infantil por MC para todo Chile se caracteriza por presentar en el período 1997-2011 un descenso de la TMI-MC y un aumento del PM-MC. CONCLUSIONES: Los resultados indican que Chile se encuentra en un estadio avanzado de la transición epidemiológica de las causas de mortalidad infantil. Sin embargo, se observan disparidades interregionales de estos indicadores, más notorias en el sur del país.

OBJECTIVE: To analyze the spatial and temporal distribution (1997-2011) of infant mortality resulting from congenital malformations (CM) in Chile. METHODS: Data on births and deaths among infants aged less than one year using ICD-10 coding were obtained from the National Statistics Institute. The percentage of deaths from CM (PD-CM) and the infant mortality rate from CM (IMR-CM) during three different periods (1997-2001, 2002-2009, 2007-2011) were estimated for Chile's administrative and natural regions (Norte Grande, Norte Chico, Central, Austral, and Sur), broken down by systems (nervous, cardiovascular, digestive, genitourinary, musculoskeletal, and chromosomal abnormalities) and by 28 specific malformations. The secular trend and the variation in the risk of death were estimated using a Poisson regression model. RESULTS: For the whole of Chile, the secular trend for the IMR-CM was negative, and the secular trend for the PD-CM was positive (P < 0,01). The IMR-CM and the PD-CM both showed mild spatial heterogeneity in all administrative and natural regions. The Central region was the natural region that came closest to showing the pattern observed nationwide. The IMR-CM involving the nervous and cardiovascular systems and specific types of CM (anencephaly, spina bifida, and atrial and ventricular septal defects) showed a negative secular trend. For Chile as a whole, the pattern of infant mortality from CM is marked by a drop in the IMR-CM and by an increase in the PD-CM over the period from 1997 to 2011. CONCLUSION: The findings suggest that Chile is in the latter stages of the epidemiological transition with respect to the causes of infant mortality. However, these indicators show disparities between regions, more pronounced in the south of the country.

Índice compuesto de fracaso antropométrico y altura geográfica en infantes jujeños (1-5 años) / Composite index of anthropometric failure and geographic altitude in children from Jujuy (1 to 5 years old)

Introducción. El índice compuesto de fracaso antropométrico (ICFA), integrado por los índices antropométricos habituales y sus combinaciones en 7 categorías, propone una medida agregada para ponderar la desnutrición como alternativa a la evaluación independiente del acortamiento, emaciación y bajo peso. Objetivo. Evaluar el ICFA en la población infantil jujeña asentada a distintos niveles altitudinales. Materiales y métodos. El peso y la talla se tomaron de los controles de niños sanos, de 1-5 años, realizados en los Centros de Atención Primaria (CAP) jujeños entre 2005 y 2007. El estado nutricional (bajo peso, acortamiento y emaciado) se caracterizó con el estándar OMS-2007. El ICFA y sus 7 grupos se calcularon agrupando los datos por sexo, edad y nivel altitudinal (tierras altas: > 2500 msnm; tierras bajas: < 2500msnm). Las diferencias porcentuales del ICFA por altura y sexo y edad se verificaron con la prueba chi-cuadrado. Resultados. Se incluyeron 8059 niños. El ICFA de tierras altas (6,1%) duplicó al de tierras bajas (3,4%) (p < 0,05) y la prevalencia de bajo peso (grupo Y) fue significativamente superior en tierras altas (p < 0,05). El ICFA y el acortamiento (grupo F) aumentaron con la edad, pero el aumento fue significativamente mayor en tierras altas. Conclusiones. Las tierras altas presentaron un IFCA significativamente mayor a expensas del acortamiento. No obstante, el índice de fracaso antropométrico no superó el 10% en los dos niveles, lo que da cuenta de un estado sanitario por desnutrición de escasa magnitud en la población infantil jujeña estudiada.

Introduction. The Composite Index of Anthropometric Failure (CIAF) is made up of typical anthropometric indicators and their combination into seven categories, and proposes an additional measure to study malnutrition as an alternative to the evaluation of stunting, wasting and underweight as separate measures. Objective. To assess the CIAF in the child population settled at different altitudinal zones in Jujuy. Population and Methods. Weight and height were obtained from healthy 1 to 5 year-old control children, measured at primary healthcare centers (PHCCs) in Jujuy between 2005 and 2007. Nutritional status indicators such as underweight, stunting and wasting were determined as per the World Health Organization 2007 child growth standards. The CIAF and its seven categories were estimated by grouping data by gender, age and altitudinal zone (highlands: >2500 MASL; lowlands: <2500 MASL). The CIAF percentage differences for height, gender and age were verified using a chi-square test. Results. A total of 8059 children were included. The CIAF for highland children (6.1%) doubled that for lowland children (3.4%) (p < 0.05), and underweight prevalence (group Y) was significantly higher in the highlands (p < 0.05). The CIAF value and stunting (group F) increased with age, but such increase was more significant in the highlands. Conclusions. A significantly higher CIAF was observed in highland children, at the expense of stunting. However, the index of anthropometric failure was not more than 10% at both the highlands and the lowlands, and this accounts for a scarcely significant malnutrition health status in the studied child population of Jujuy.

Prevalencia de sobrepeso y obesidad en escolares jujeños de diferente nivel altitudinal según las referencias IOTF, CDC y OMS / Prevalence of overweight and obesity in students from different altitudinal zones of Jujuy according to three intvernational references (IOTF, CDC and WHO)

Introducción. Se comparan las prevalencias de sobrepeso (SP) y obesidad (OB) en escolares jujeños de distintos niveles altitudinales utilizando las referencias de la International Obesity Task Force (IOTF), de los Centers for Disease Control (CDC) y de la Organización Mundial de la Salud (OMS), y la concordancia entre ellas. Materiales y métodos. Los datos de peso y talla de 15 541 escolares (PROSANE) se agruparon en tierras altas (TA) (= 2500 msnm) y bajas (TB) (< 2500 msnm), y en dos grupos de edad (5 a 6,99 y 11 a 12,99 años). Se calcularon las prevalencias de SP, OB y SP+OB según las referencias. Las diferencias entre variables y prevalencias se establecieron con la prueba de la ?² y la prueba de la t, y la concordancia entre criterios, con el índice kappa. Resultados. Los escolares de las TA presentaron menor peso, talla e índice de masa corporal (IMC) (p< 0,05). Las prevalencias de SP, OB y SP+OB con OMS fueron superiores, excepto para SP en ambos sexos de 11 a 12,99 años de TB y TA. Independientemente de las referencias, el sexo y la edad, las prevalencias de SP, OB y SP+OB fueron, en general, mayores en las TB. La concordancia entre las referencias IOTF/CDC fue buena-muy buena, y entre estas y las de la OMS, regular-moderada. Conclusiones. Los escolares de TA presentaron menor prevalencia de SB y OB. La mejor concordancia se dio entre las referencias IOTF y CDC.

Introduction. Prevalences of overweight and obesity in students from different altitudinal zones of Jujuy are compared using the International Obesity Task Force (IOTF), the Centers for Disease Control (CDC) and the World Health Organization (WHO) references, and the agreement among them. Material and Methods. Weight and height data from 15 541 students were grouped in highlands (HL) (=2500 MASL) and lowlands (LL) (<2500 MASL) and in two age groups (5-6.99 years old and 11-12.99 years old). Overweight and obesity prevalences were calculated according to the different references. The differences in outcome measures and prevalences were established using the ?2 test and the t test, and agreement among the criteria was calculated using the kappa index. Results. Students from the HL had lower weight, height and body mass index (BMI) values (p< 0.05). Overweight and obesity prevalences compared to the WHO reference were higher, except for overweight in students of both sexes, from 11 to 12.99 years old, from the HL and the LL. Regardless of the references, gender and age, overweight and obesity prevalences were generally higher in the LL. Agreement between the IOTF and the CDC was good-very good, and agreement among them and the WHO was fair-moderate. Conclusions. Students from the HL had a lower overweight and obesity prevalence. The greatest agreement was observed between the IOTF and the CDC references.

Indicadores de aislamiento y sedentarismo en poblaciones de altura de la Provincia de Jujuy (Republica Argentina) / Isolation and sedentarisness in population of highland communities in the Jujuy Province (Republica Argentina)

Surnames are the result of historic and cultural processes which give information about the ethnic composition and genetic structure of populations. Based on the use of isolation and sedentarisness estimators, obtained from surnames frequency and distribution, the population dynamics of highland communities located at the Province of Jujuy (Northwest of Argentina), situated in two ecologically different regions, was analysed. Surnames were obtained from register of electors (1982) and they correspond to 67 villages of Quebrada of Humahuaca and Puna Jujeña. The surnames were analysed exactly as they were registered (NM = Non-merged) and merged according to their spelling and or similarity in pronunciation (M = Merged). The following estimators were used: 1) percentage of the population covered by unique surnames; 2) percentage of the population covered by the most frequent surnames; 3) ratio between number of individuals and number of surnames. Inter-population differences were detected by means of non-parametric tests. It was observed that, in general, there are no statistically significant differences between NM and M data and among the towns in Quebrada de Humahuaca and Puna, but there were differences according to whether they were located on or away from the main road between regions. These results were compared with those of other populations and we conclude that the simultaneous use of the 4 estimators, to characterize the isolation or sedentarisness of vast population groups, show highly consistent results.