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.

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.

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.