Waist circumference percentiles for Hispanic-American children and comparison with other international references.

INTRODUCTION: Waist circumference (WC) constitutes an indirect measurement of central obesity in children and adolescents. OBJECTIVE: To provide percentiles of WC for Hispanic-American children and adolescents, and compare them with other international references. MATERIALS AND METHODS: The sample comprised 13 289 healthy children between 6 and 18 years coming from public schools of middle and low socioeconomic levels in different parts of Argentina, Cuba, Spain, Mexico, and Venezuela. The LMS method to calculate WC percentiles was applied. Sex and age differences were assessed using Student's t test and ANOVA (SPSS v.21.0). Comparisons were established with references from the United States, Colombia, India, China, Australia, Kuwait, Germany, Tunisia, Greece, and Portugal. RESULTS: WC increases with age in both sexes. Boys show higher WC in P3, P50, and P97. Comparison of 50th and 90th percentiles among populations from diverse sociocultural and geographical contexts shows high variability, not all justified by the measurement method. DISCUSSION AND CONCLUSIONS: Specific WC percentiles for sex and age, and P90 cut-off points are provided; these values are potentially useful to assess central obesity in Hispanic-American adolescent children.

SUBSCAPULAR AND TRICEPS SKINFOLDS REFERENCE VALUES OF HISPANIC AMERICAN CHILDREN AND ADOLESCENTS AND THEIR COMPARISON WITH THE REFERENCE OF CENTERS FOR DISEASE CONTROL AND PREVENTION (CDC).

INTRODUCTION: the assessment of the skinfold thickness is an objective measure of adiposity. Therefore, it is a useful tool for nutritional diagnosis and prevention of metabolic risk associated with excess fat in chilhood and adolescence. OBJECTIVE: to provide percentiles of subscapular and triceps skinfolds for Hispanic American schoolchildren and compare them with those published by the Centers for Disease Control and Prevention (CDC) from United States, that it have been commonly used as a reference in most of these countries. METHODS: subscapular and triceps skinfolds were measured in 9.973 schoolchildren 4-19 aged from Spain, Argentina, Cuba, Venezuela and Mexico with Holtain caliper with 0.2 mm accuracy. Percentiles were obtained with the LMS statistical method and were presented in tables divided in stages of 6 months and in curves graphics. The difference between Hispanic American and CDC mean values were provided for P3, P50 and P97 in mm and also were graphically represented. RESULTS: skinfolds measurements obviously increased with age in both sexes but, in boys, this increase is much more marked in highest percentiles between 8 and 13 years; this maximum is reached earlier than what occurs in CDC reference. In both sexes, all percentiles analized in Hispanic American schoolchildren were higher than the CDC reference except P97 up to 10 or 13 years that was notably smaller. CONCLUSIONS: the skinfolds percentiles of Hispanic American children and adolescents differ from CDC that are usually used as reference. The values of subscapular and triceps skinfolds provided in this study, could be applied to populations of a similar ethnic background, especially in comparative studies of body composition.

Introducción: la evaluacion del grosor de los pliegues subcutáneos es una medida objetiva de la adiposidad. Es por tanto una herramienta útil para el diagnóstico nutricional y la prevención del riesgo metabólico asociado al exceso de grasa en la infancia y adolescencia. Objetivo: proporcionar valores percentilares de los pliegues adiposos subcutáneos subescapular y tricipital para escolares hispanoamericanos y compararlos con los valores publicados por los Centros para el Control y Prevención de Enfermedades (CDC) de los Estados Unidos, que comunmente se emplean como referencia en estos países. Métodos: se midió el pliegue subescapular y tricipital en 9.973 escolares entre 4 y 19 años procedentes de España, Argentina, Cuba, Venezuela y México con un calibre Holtain de 0,2 mm de precisión. Los percentiles fueron calculados mediante el método estadístico LMS y presentados en tablas divididas en intervalos de seis meses y en gráficos de curvas. La diferencia entre los valores medios hispanoamericanos y los valores del CDC se muestran para el P3, P50 y P97 en mm, y también gráficamente. Resultados: las medidas de los pliegues subcutáneos se incrementan obviamente con la edad pero, en niños, este incremento es mucho más marcado en los percentiles superiores entre los 8 y 13 años; este máximo es alcanzado antes que en la referencia del CDC. En ambos sexos, todos los percentiles analizados fueron superiores en los escolares hispanoamericanos, exceptuando el P97 por encima de los 10 o 13 años, donde resultó notablemente inferior. Conclusiones: los percentiles de pliegues adiposos de los niños y adolescentes hispanoamericanos difieren de la referencia del CDC. Los valores del pliegie subescapular y tricipital proporcionados en este estudio podrían ser aplicados en poblaciones de similar origen étnico, especialmente en estudios comparativos de la composición corporal.

Subscapular and triceps skinfolds reference values of Hispanic American children and adolescents and their comparison with the reference of Centers for Disease Control and Prevention (CDC) / Valores de referencia para los pliegues adiposos subescapular y tricipital de niños y adolescentes hispanoamericanos y su comparación con la referencia de los centros para el control y prevención de enfermedades (CDC)

Introduction: the assessment of the skinfold thickness is an objective measure of adiposity. Therefore, it is a useful tool for nutritional diagnosis and prevention of metabolic risk associated with excess fat in chilhood and adolescence. Objective: to provide percentiles of subscapular and triceps skinfolds for Hispanic American schoolchildren and compare them with those published by the Centers for Disease Control and Prevention (CDC) from United States, that it have been commonly used as a reference in most of these countries. Methods: subscapular and triceps skinfolds were measured in 9.973 schoolchildren 4-19 aged from Spain, Argentina, Cuba, Venezuela and Mexico with Holtain caliper with 0.2 mm accuracy. Percentiles were obtained with the LMS statistical method and were presented in tables divided in stages of 6 months and in curves graphics. The difference between Hispanic American and CDC mean values were provided for P3, P50 and P97 in mm and also were graphically represented. Results: skinfolds measurements obviously increased with age in both sexes but, in boys, this increase is much more marked in highest percentiles between 8 and 13 years; this maximum is reached earlier than what occurs in CDC reference. In both sexes, all percentiles analized in Hispanic American schoolchildren were higher than the CDC reference except P97 up to 10 or 13 years that was notably smaller. Conclusions: the skinfolds percentiles of Hispanic American children and adolescents differ from CDC that are usually used as reference. The values of subscapular and triceps skinfolds provided in this study, could be applied to populations of a similar ethnic background, especially in comparative studies of body composition (AU)

Introducción: la evaluación del grosor de los pliegues subcutáneos es una medida objetiva de la adiposidad. Es por tanto una herramienta útil para el diagnóstico nutricional y la prevención del riesgo metabólico asociado al exceso de grasa en la infancia y adolescencia. Objetivo: proporcionar valores percentilares de los pliegues adiposos subcutáneos subescapular y tricipital para escolares hispanoamericanos y compararlos con los valores publicados por los Centros para el Control y Prevención de Enfermedades (CDC) de los Estados Unidos, que comunmente se emplean como referencia en estos países. Métodos: se midió el pliegue subescapular y tricipital en 9.973 escolares entre 4 y 19 años procedentes de España, Argentina, Cuba, Venezuela y México con un calibre Holtain de 0,2 mm de precisión. Los percentiles fueron calculados mediante el método estadístico LMS y presentados en tablas divididas en intervalos de seis meses y en gráficos de curvas. La diferencia entre los valores medios hispanoamericanos y los valores del CDC se muestran para el P3, P50 y P97 en mm, y también gráficamente. Resultados: las medidas de los pliegues subcutáneos se incrementan obviamente con la edad pero, en niños, este incremento es mucho más marcado en los percentiles superiores entre los 8 y 13 años; este máximo es alcanzado antes que en la referencia del CDC. En ambos sexos, todos los percentiles analizados fueron superiores en los escolares hispanoamericanos, exceptuando el P97 por encima de los 10 o 13 años, donde resultó notablemente inferior. Conclusiones: los percentiles de pliegues adiposos de los niños y adolescentes hispanoamericanos difieren de la referencia del CDC. Los valores del pliegie subescapular y tricipital proporcionados en este estudio podrían ser aplicados en poblaciones de similar origen étnico, especialmente en estudios comparativos de la composición corporal (AU)

Anthropometric parameters in screening for excess of adiposity in Argentinian and Spanish adolescents: evaluation using receiver operating characteristic (ROC) methodology.

BACKGROUND: Various anthropometric parameters have been proposed for defining overweight in adolescence, but few studies have evaluated their diagnostic accuracy in comparative terms, using samples from different regions. AIM: To compare the performance of anthropometric parameters in determining the excess of adiposity in Argentinian and Spanish adolescents. SUBJECTS AND METHODS: The sample is composed of 1781 Argentinian and 1350 Spanish subjects, aged 12-17 years. Excess adiposity was defined as percentage BF in the 90th percentile or higher. ROC curves established the validity of parameters to define excess adiposity. RESULTS: Descriptive statistics showed differences between the Argentinian and Spanish samples. ROC curves indicate that all the parameters analysed had, in the Spanish and Argentinian samples, a positive and elevated association with excess of adiposity. The waist-to-height ratio had the highest value of the area under ROC curve (AUC), while conicity index and waist-to-hip ratio had the lowest. CONCLUSIONS: Differences exist with respect to size and body composition between the Argentinian and Spanish samples. ROC curves reflect a general pattern of variation. Waist-to-hip ratio and conicity index are less desirable in the diagnosis of excess adiposity and the most desirable is waist-to-height ratio.

Population relationships in the Mediterranean revealed by autosomal genetic data (Alu and Alu/STR compound systems).

The variation of 18 Alu polymorphisms and 3 linked STRs was determined in 1,831 individuals from 15 Mediterranean populations to analyze the relationships between human groups in this geographical region and provide a complementary perspective to information from studies based on uniparental markers. Patterns of population diversity revealed by the two kinds of markers examined were different from one another, likely in relation to their different mutation rates. Therefore, while the Alu biallelic variation underlies general heterogeneity throughout the whole Mediterranean region, the combined use of Alu and STR points to a considerable genetic differentiation between the two Mediterranean shores, presumably strengthened by a considerable sub-Saharan African genetic contribution in North Africa (around 13% calculated from Alu markers). Gene flow analysis confirms the permeability of the Sahara to human passage along with the existence of trans-Mediterranean interchanges. Two specific Alu/STR combinations-CD4 110(-) and DM 107(-)-detected in all North African samples, the Iberian Peninsula, Greece, Turkey, and some Mediterranean islands suggest an ancient genetic background of current Mediterranean peoples.

Population data for 15 Y-chromosome STRs in a population sample from Quito (Ecuador).

Population frequencies for the 9 Y-STR loci included in the "minimal haplotype" from Y-STR Haplotype Reference Database (YHRD), plus other 6 Y-STRs (DYS437, DYS438, DYS439, GATA A7.2, GATA H4 and GATA A10) were obtained for a sample of 120 males from Quito (Ecuador). One hundred and sixteen unique haplotypes were identified within the sample. Haplotype diversity (0.9994) was among the highest in comparison to other populations from Iberia and South-America. Genetic distances were calculated and our sample presented significative differences with all other samples, the lowest values being with a Guinean sample.

Genetic variability of 16 Y-chromosome STRs in a sample from Equatorial Guinea (Central Africa).

Nine Y-STR loci from the "minimal haplotype" included in Y-STR Haplotype Reference Databases (YHRD) together with eight additional Y-STRs (DYS437, DYS438, DYS439, DYS460, DYS461, GATA C4, GATA H4 and GATA A10) were analyzed in a sample of 101 males from Equatorial Guinea living in Madrid. Haplotype and allelic frequencies were calculated and genetic diversities were estimated for each genetic system as well as for the whole haplotype. An unexpected high frequency (6%) of intermediate alleles (13.2 and 14.2) was found in DYS385. For DYS19, two alleles were found in one sample. Another sample failed to amplify with DYS393 primers using either PowerPlex Y System (Promega Corporation) or the Y-PLEXtrade mark 12 (Reliagene, New Orleans, LA) commercial kits. Comparison between Equatorial Guinea and another African population (Mozambique; South East Coast) revealed a significant pairwise Phi(st) value between them (Phi(st)=0.03309; P=0.00000).

Population data for 16 Y-chromosome STRs in four populations from Pyrenees (Spain).

Population frequencies for the eight Y-STR loci included in the "minimal haplotype" from Y-STR Haplotype Reference Database (YHRD) plus other eight Y-STRs (DYS434, DYS435, DYS436, DYS437, DYS438, DYS439, GATA H4 and GATA A10) were obtained for a sample of 133 males from four main geographical areas in the Pyrenees (Spain): Vall D'Aran (Lérida), Cerdanya (Gerona), Alt Urgell (Lérida) and Jacetania (Huesca). Haplotype diversities were estimated in the four populations.

Secular changes in stature and biacromial and bicristal diameters of young adult Spanish males.

Measurements of stature and biacromial and bicristal diameters were obtained for two samples of young adult male university students, one from 1901 to 1919 and the other from 1989 to 1991. Means and standard deviations were calculated for each measurement and for three indices. Significant positive trends in stature and biacromial and bicristal diameters were apparent between the two samples: 7.3 cm (4.4%), 3.6 cm (9.9%), and 3.4 cm (12.5%), respectively. The results for stature were compared with other Spanish samples from the beginning of the century to the present. These comparisons also showed positive secular changes, although the differences among samples may have been conditioned by regional variations in socioeconomic conditions, industrialization, and so on, all of which complicate the interpretation of the magnitude of changes in Spain. In summary, the results show a positive secular trend in body dimensions, and this can be related to the improvement in living conditions in Spain, especially during the last 40 years. © 1993 Wiley-Liss, Inc.