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.

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.

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.

So close, so far away: analysis of surnames in a town of twins (Cândido Godói, Brazil).

Cândido Godói is a small Brazilian town known for high rates of twin birth. In 2011, a genetic study showed that this localized high rate of twin births could be explained by a genetic founder effect. Here we used isonymic analysis and surname distribution to identify population subgroups within 5316 inhabitants and 665 different surnames. Four clusters were constructed based on different twin rates (P < 0.001; MRPP test). Fisher's α and consanguinity index showed low and high values, respectively, corresponding with observed values in isolated communities with high levels of genetic drift. Values of A and B estimators confirmed population isolation. Three boundaries were identified with Monmonier's maximum difference algorithm (P = 0.007). Inside the isolated sections, surnames of different geographic origins, language, and religion were represented. With an adequate statistical methodology, surname analyses provided a close approximation of historic and socioeconomic background at the moment of colony settlement. In this context, the maintenance of social and cultural practices had strong implications for the population's structure leading to drift processes in this small town, supporting the previous genetic study.

Geographic patterns of genome admixture in Latin American Mestizos.

The large and diverse population of Latin America is potentially a powerful resource for elucidating the genetic basis of complex traits through admixture mapping. However, no genome-wide characterization of admixture across Latin America has yet been attempted. Here, we report an analysis of admixture in thirteen Mestizo populations (i.e. in regions of mainly European and Native settlement) from seven countries in Latin America based on data for 678 autosomal and 29 X-chromosome microsatellites. We found extensive variation in Native American and European ancestry (and generally low levels of African ancestry) among populations and individuals, and evidence that admixture across Latin America has often involved predominantly European men and both Native and African women. An admixture analysis allowing for Native American population subdivision revealed a differentiation of the Native American ancestry amongst Mestizos. This observation is consistent with the genetic structure of pre-Columbian populations and with admixture having involved Natives from the area where the Mestizo examined are located. Our findings agree with available information on the demographic history of Latin America and have a number of implications for the design of association studies in population from the region.

[Prevalence of malnutrition in institutionalized intellectually disabled patients]. / Prevalencia de malnutricion en pacientes con discapacidad intelectual institucionalizados.

As patients with intellectual and developmental disability (ID) may be more exposed to unfavorable factors, they are at higher risk of suffering nutritional alterations. Our objective was to determine prevalence of malnutrition in institutionalized patients with ID. An evaluation of the nutritional status through determination of transversal anthropometric parameters of weight (kg) and height (cm) was made on 614 individuals (352 men and 262 women) institutionalized at Colonia Nacional Montes de Oca, Buenos Aires Province, Argentina. Body mass index and prevalence of underweight, overweight and obesity cases by sex and ID type: mild, moderate and severe intellectual disability were determined. Regardless of sex, prevalence of underweight, overweight and obesity were of 2.9%, 30% and 27.7%, respectively. Regardless of degree of ID, greater prevalence of obesity (41.2%) was found amongst women, while overweight (34.7%) was more frequent amongst men. Taking the degree of ID and regardless of sex, greater prevalence of underweight was observed in severe ID, and overweight and obesity amongst mild ID. No any of the patients with mild ID presented underweight. Taking into account sex and ID, higher prevalence of underweight and overweight were observed amongst men with mild ID, (7% and 38.4%, respectively) and of obesity in women with moderate ID (44%). Results obtained would indicate the importance of caloric intake and energy consumption control in adults with ID, paying particular attention to life conditions and alimentary disorders in terms of the degree of ID and their multiple associated disabilities.

Isonymy structure of Buenos Aires city.

The isonymy structure of Buenos Aires was studied based on its surname frequency. Information on 2,552,359 voters of the 28 Buenos Aires districts was used to estimate Lasker's coefficient of relationship by isonymy (R(i)), surname diversity according to Fisher's alpha, the coefficient of consanguinity resulting from random isonymy (F), and Nei's, Lasker's and the Euclidean isonymy distances. These distances were correlated with geographic distances, which were calculated by assigning an arbitrary point to each district and measuring distances on a map of the city. The R(i) x 10(5) and F x 10(4) averages of the districts located south of Rivadavia Avenue were higher (R(i) = 66.08; F = 3.4) than those situated north of that avenue (R(i) = 46.60; F = 2.4) (p < 0.001). Fisher's alpha showed the opposite behavior (north, alpha = 1,055.5; south, alpha = 757.2). There was a significant correlation (p < 0.001) between geographic distance and Nei's and the Euclidean distances (0.496 and 0.503, respectively), but the correlation was not significant for Lasker's distance (0.051). These results indicate isolation by distance in the city of Buenos Aires and reveal subdivision of the metropolitan population, with greater consanguinity and a lesser variety of surnames in the districts located in the southern section of the city. This structure agrees with the fragmentation and social, cultural, and economic differences observed among the districts of this Latin American metropolis.

Geographic altitude, surnames, and height variation of Jujuy (Argentina) conscripts.

The height records of 48,589 conscripts born in Jujuy between 1870 and 1960 were examined in order to study the variation in adult male height (AMH) in terms of geographical altitude and surnames. Data were clustered by origin of surnames (divided into native and foreign names), decades, and according to the four Jujenean geographical regions distributed along an altitudinal gradient (Puna, Quebrada, Valle, and Ramal). The variation of surnames, geographical altitude, and time on human height were examined by analysis of variance. Regardless of the drafting year, individuals in the four regions bearing foreign surnames proved significantly taller (P < 0.001) than those who had a native surname. Average height, regardless of ethnic group, presented a reverse relationship to geographical altitude. A higher AMH was found in individuals bearing foreign surnames in Jujuy and lower ones in the population located in the highlands and bearing native surnames. Interregional and intergroup AMH variations would be affected by the complex interaction between geographical altitude and factors associated to it and by the ethnic characteristics of these population as well.

Brief communication: Restricted geographic distribution for Y-Q* paragroup in South America.

We analyzed 21 paragroup Q* Y chromosomes from South American aboriginal and urban populations. Our aims were to evaluate the phylogenetic status, geographic distribution, and genetic diversity in these groups of chromosomes and compare the degree of genetic variation in relation to Q1a3a haplotypes. All Q* chromosomes from our series and five samples from North American Q* presented the derivate state for M346, that is present upstream to M3, and determined Q1a3* paragroup. We found a restrictive geographic distribution and low frequency of Q1a3* in South America. We assumed that this low frequency could be reflecting extreme drift effects. However, several estimates of gene diversity do not support the existence of a severe bottleneck. The mean haplotype diversity expected was similar to that for South American Q1a3* and Q1a3a (0.478 and 0.501, respectively). The analysis of previous reports from other research groups and this study shows the highest frequencies of Q* for the West Corner and the Grand Chaco regions of South America. At present, there is no information on whether the phylogenetic status of Q* paragoup described in previous reports is similar to that of Q1a3* paragroup though our results support this possibility.

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.

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.

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.

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.

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.

[Hematocrit values and prevalence of anemia in schoolchildren of Jujuy]. / Valores del hematocrito y prevalencia de anemia en escolares jujeños.

The hematocrit (Ht), as an indicator of anemia in individuals and populations, shows variations in relation to mesologic and genetic factors. Anemia is an endemic disease with insufficiently known prevalence in Argentina, in different age and risk groups and particularly in schoolchildren. The aim of this work was to study the variation of schoolchildren Ht in San Salvador of Jujuy city located at 1,200 m.a.s.l. in order to evaluate the prevalence of anemia and to relate these variations to the socio-economic characteristics of the population. The Ht data proceed from 17,580 schoolchildren of private and public schools. They were grouped by age, sex and socio-economic level. Were considered as anemic the children whose Ht was found: a) under a minimal value accepted for the 1200 m level; b) below 2 standard deviations. For the statistical analysis, ANOVA, chi 2 and correlation coefficient were employed. Independently of age, sex and socio-economic level, the average Ht values agree with those adjusted for the altitude. We observed: a) statistically significant intersex differences, males showing higher values than females; b) a trend to the Ht augmentation in relationship to the increase of the socio-economic level. Independently of the criterion used the prevalence of anemia was low in both sexes, age groups and in all socio-economic levels. Ht values: a) are representative of a schoolchildren population located at a moderate altitude; b) in spite of a trend to decrease in the low socio-economic level, this did not surpass, in most cases, the critical anemia level; c) are not indicative of malnutrition in the schoolchildren examined.

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.

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.

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.

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.