[Breastfeeding, obesity and metabolic syndrome at school age]. / Lactancia materna, obesidad y síndrome metabólico en la edad escolar.

INTRODUCTION: Breastfeeding (BF) can be a protective factor against obesity and its associated metabolic complications. OBJECTIVE: To determine the association between breastfeeding history and present obesity, metabolic syndrome (MS) and insulin resistance (IR). PATIENTS AND METHODS: Cross-sectio nal study in 20 public schools in Santiago, Chile. Anthropometry and blood pressure were assessed. Blood lipids, glucose, insulin and HOMA index were measured in a fast blood sample. Parents answe red a survey on BF. MS was defined according to Cook's criteria and IR as HOMA > 90th percentile. Parents answered a survey about the antecedent of breastfeeding. Chi2 and Fischer tests were used (SSPS). RESULTS: 3,278 surveys were valid. Average age: 11.4 ± 1 years, 52.3% were female. Most of them (98.2%) were breasted, with a 15.9% prevalence of obesity versus 18.6% in the group that was not breastfed (p = 0.039). There was a non-significant trend of higher prevalence in MS and its components (except IR) in the non-breastfed group. The group breastfed from three to six months had a lower prevalence of obesity and MS components than the 0 to 3 months group ; the effect was the opposite when BF lsted longer than nine months. CONCLUSIONS: The prevalence of obesity was higher in children that did not received breastfeeding. A longer breastfeeding time during the first semester of life was associated with lower prevalence of obesity and metabolic complications.

[Waist-to-height ratio does not change with gender, age and pubertal stage in elementary school children]. / La razón cintura estatura en escolares no varía con el género, la edad ni la maduración puberal.

BACKGROUND: Waist-to-height ratio (WHtR) is a cardiometabolic risk indicator in children. A value greater than or equal to 0.55 is an effective screening tool for identifying obese children with metabolic syndrome. However, it is unclear whether this cutoff can be applied equally to any age or gender. AIM: To analyze the variability of WHtR by age, gender and pubertal stage in elementary school children. PATIENTS AND METHODS: Cross-sectional study in 2,980 school children (6-14 years old, 51% male) of Santiago, Chile. We measured weight, height and waist circumference and calculated body mass index and WHtR. Pubertal stage was assessed and classified as peripubertal (Tanner I and II) and pubertal (Tanner III, IV and V). RESULTS: The mean age was 9.9 ± 2.3 years, with no gender difference (p = 0.5). Eighty one percent of boys and 59.4% of girls were peripubertal (p < 0.001). The association between age-adjusted WHtR by gender and pubertal stage was not significant (p = 0.409). Therefore mean, standard deviation and percentiles of WHtR were calculated without sex and pubertal stage segmentations. CONCLUSIONS: Since WHtR does not vary with age, gender and pubertal status in elementary school children, it is possible to use a single cutoff value, previously defined in this population, to identify children with cardiometabolic risk.

[Total/HDL cholesterol ratio and non HDL cholesterol as predictors for increased intima media thickness]. / Relación colesterol total a HDL y colesterol no HDL: los mejores indicadores lipídicos de aumento de grosor de la íntima media carotidea.

BACKGROUND: LDL, HDL cholesterol and triglycerides, are the most commonly used lipid cardiovascular risk predictor indicators. However population based studies have shown that non-HDL cholesterol and total/HDL cholesterol ratio are better predictors, are easy to measure and do not require fasting. AIM: To determine which lipid indicators are better determinants of subclinical atherosclerosis, measured by intima media thickness (IMT) among subjects without demonstrated atherosclerosis. MATERIAL AND METHODS: Lipid profile, height, weight, blood pressure and bilateral IMT, measured by ultrasound with automatic border recognition software, were assessed in 770 men and 854 women aged 45 ± 11 years, in Santiago de Chile. RESULTS: Mean total cholesterol was 202, HDL 50, LDL 121, triglycerides 157 and non-HDL cholesterol 152 mg/dl. Total/HDL cholesterol ratio was 4.3. Mean IMT was 0.62 mm. All lipid markers were significantly correlated with IMT. This correlation was higher for non-HDL cholesterol (r = 0.24, p < 0.0001) and total/HDL cholesterol ratio(r = 0.23, p < 0.0001). In both men and women, total/HDL cholesterol ratio was the best predictor of having an IMT over the 75th percentile (odds ratio 1.21, 95% confidence intervals 1.09-1.35, p < 0.01). CONCLUSIONS: Total/HDL cholesterol ratio was the best determinant of subclinical atherosclerosis.

[Association of carotid intima media thickness with blood pressure and HDL cholesterol in children]. / La presión arterial es un importante marcador de ateroesclerosis subclínica en niños.

BACKGROUND: Cardiovascular risk factors must be controlled since childhood. AIM: To assess the association of carotid intima media thickness (CIMT) with the components of the metabolic syndrome in Children. MATERIAL AND METHODS: Cross sectional assessment of 299 children aged 11.5 ± 0.9 years (58% women) with and without metabolic syndrome components. Anthropometric parameters and blood pressure were measured and a blood sample was obtained to measure blood glucose and lipids. CIMT was measured using high resolution ultrasound. RESULTS: Ninety three percent of children were post puberal, 64% were overweight and 25% had metabolic syndrome. Mean and maximum CIMT correlated with systolic blood pressure (r = 0.21 and 0.21 respectively p < 0.01). Children with a CIMT over the 75th percentile had higher blood pressure and lower HDL cholesterol. A stepwise logistic regression accepted both variables as predictors of CIMT with odds ratios for mean CIMT of 1.46 (1.19-1-79) and 0.81 (0.7-0.94) per five units of change, respectively. CONCLUSIONS: In this group of children systolic blood pressure and HDL cholesterol are associated to CIMT.

[Cardiometabolic risk in children with severe obesity]. / Riesgo cardiometabólico en niños con obesidad grave.

Introduction: Introduction: severe obesity has had a greater increase than non-severe obesity in Chilean schoolchildren during the last years. We do not know whether the cut-off point currently used to define severe obesity in children (BMI ≥ + 3 DE, WHO-2007 curves) is associated with a greater biological risk in our population. Objective: to describe and compare cardiometabolic risk in schoolchildren with severe vs. non-severe obesity. Methods: a secondary analysis of a sample of 3,325 schoolchildren was performed, in which cardiometabolic risk factors were studied. The prevalence of these was compared in the subsample of 589 schoolchildren with obesity according to whether it was severe or not, and the respective ORs were calculated. Results: mean age was 11.4 ± 0.98 years, 46 % were girls, and 11.5 % of the sample had severe obesity, with a higher prevalence of most of the factors studied and no differences in chronic disease, obesity or education in parents, or physical activity of the child. The risk of those with severe obesity for central obesity, insulin resistance, high blood pressure, and metabolic syndrome reached an OR of 12.9, 3.2, 2.67, and 1.92, respectively, as compared to those with non-severe obesity. Conclusion: this definition of severe obesity in childhood favors the identification of children with higher cardiometabolic comorbidity, which allows to focus the efforts of secondary prevention and its most timely treatment.

Introducción: Introducción: la obesidad grave ha tenido un mayor aumento que la obesidad no grave en los escolares chilenos durante los últimos años. Desconocemos si el punto de corte actualmente utilizado para definir la obesidad grave (IMC ≥ + 3 DE, curvas OMS-2007) se asocia a un mayor daño biológico en nuestra población pediátrica. Objetivo: describir y comparar el riesgo cardiometabólico en escolares con obesidad grave y no grave. Método: se realizó un análisis secundario de una muestra de 3325 escolares en los que se estudiaron los factores de riesgo cardiometabólico. Se comparó la prevalencia de estos factores en los que presentaban obesidad según fuera esta grave o no, calculándose los OR respectivos. Resultados: de los 589 sujetos con obesidad, con una media de edad de 11,4 ± 0,98 años, el 46 % eran de género femenino y el 11,5 % presentaban obesidad grave, con mayor prevalencia de la mayoría de los factores estudiados y sin diferencias en cuanto a antecedentes parentales de enfermedad crónica u obesidad, educación de los padres y actividad física del niño. Los niños con obesidad grave tenían un mayor riesgo de obesidad central (OR: 12,9), resistencia insulínica (OR: 3,2), HTA (OR: 2,67) y síndrome metabólico (OR:1,92). Conclusión: esta definición de obesidad grave en la niñez favorece la identificación de los niños con mayor comorbilidad cardiometabólica, lo cual permite focalizar los esfuerzos de prevención secundaria y su tratamiento más oportuno.

[Cardiovascular risk factors among young subjects with high carotid intima media thickness]. / Perfil de riesgo cardiovascular en adultos jóvenes asintomáticos con grosor íntima media carotídeo elevado.

BACKGROUND: Cardiovascular risk factor (RF) assessment is essential to prevent and predict cardiovascular disease. The presence of RF at early ages, are determinant for the presence of atherosclerosis later in life. AIM: To determine the RF profile of young subjects with high carotid intima media thickness (CIMT). MATERIAL AND METHODS: We studied 689 subjects (50% women, mean age 36±6 years) from Santiago, Chile. We determined body mass index (BMI), waist circumference, blood pressure, fasting serum lipids, blood glucose and C-reactive protein. CIMT was assessed by ultrasound using an automatic border recognition software. RESULTS: Body mass index, waist circumference, blood pressure and serum lipids were significantly higher among subjects located in the higher CIMT quartile. Also, subjects in the higher quartile of CIMT had a higher prevalence of three or more RF compared with the lower quartile (p = 0.01). Finally, individuals with three or more RF showed three times more risk of being in the higher CIMT quartile, than subjects with no RF (odds ratio = 3.1, p < 0.01). CONCLUSIONS: There is a negative influence of cardiovascular RF on CIMT among young subjects.

[Risk factors for a high carotid intima media thickness among healthy adults]. / Hipertensión arterial: el factor de riesgo más importante para grosor íntima-media carotídeo elevado y placa carotídea en adultos de Santiago.

BACKGROUND: Carotid intima media thickness (CIMT) is a marker of cardiovascular damage that can be modified by traditional risk factors. AIM: To determine attributable risk factors for a high CIMT among healthy adults. MATERIAL AND METHODS: A sample of 1270 individuals (636 males and 634 females) aged 44 ± 11 years, was studied. Blood pressure, weight, height, lipid profile and blood glucose were measured in all. CIMT and the presence of atherosclerotic plaques were determined by carotid ultrasound. Standard criteria were used to define hypertension, dyslipidemia and diabetes. RESULTS: Mean CIMT in the sample studied was 0.62 ± 0.01 mm and percentile 75 was 0.67. The most important risk factor for a CIMT over percentile 75 and the presence of atherosclerotic plaques was hypertension with attributable risks of 54 and 57%, respectively. CONCLUSIONS: In this sample, the main risk factor for a high CIMT was hypertension.

[Normal plasma insulin and HOMA values among Chilean children and adolescents]. / Insulinemia e índice HOMA en niños y adolescentes chilenos.

BACKGROUND: Plasma insulin and HOMA (homeostasis model assessment) index, used to determine insulin resistance, do not have local standard values for children and adolescents in Chile. AIM: To establish the normal reference intervals for insulin and HOMA in children and adolescents aged 10-15 years, according to sex and puberal maturation. MATERIAL AND METHODS: A cross-sectional study of 2,153 children and adolescents from Puente Alto County was performed, during 2009 and 2010. Anthropometry and self-report of puberal maturation were assessed. Fasting glucose (hexoquinase) and insulin blood levels (chemiluminiscence), were determined and HOMA index was calculated. Percentile distributions of these variables were calculated. RESULTS: The reference group included only subjects with normal body mass index and fasting blood glucose (n = 1,192). Girls had higher insulin and HOMA values than boys (12.5 ± 6.0 and 9.1 ± 4.9 µÏ‹/mL (p < 0.01) and 2.7 ± 1.4 and 2.1 ± 1,1 (p < 0.01), respectively). Subjects with Tanner I and II pubertal stages had lower insulin and HOMA mean values than subjects with Tanner III and IV (9.0 ± 4.3 and 12.5 ± 6.2µÏ‹/ml (p < 0.01) and2.0 ± 1 and2.8 ± 1.4 (p < 0.01), respectively). CONCLUSIONS: The 90th percentile of insulin and HOMA distributions according to sex and maturation, was selected as the upper cut-off point to identify individuals with insulin resistance. HOMA cutoff point for Tanner I and II boys was 3.2, for Tanner I and II girls was 4.1, for Tanner III and IV boys was 4.2 and for Tanner III and IV girls was 5.0.

High sensitivity C-reactive protein and endothelial function in Chilean patients with history of Kawasaki disease.

Kawasaki disease (KD) produces endothelial inflammation, which may lead to dilatation and aneurysms of coronary and peripheral arteries. Previous studies have suggested that these patients can present endothelial dysfunction that can predispose to coronary vascular events late after KD. The purpose of this study was to determine the cardiovascular risk profile and endothelial function of Chilean children with history of KD. In a prospective case-control study, 11 patients with history of KD (age 10.6 +/- 2.0 years, interval from initial episode 8.1 +/- 3.6 years) and 11 healthy, age-, gender-, and BMI z score-matched controls were evaluated with blood pressure (BP), a fasting lipid profile, high sensitivity C-reactive protein (hsCRP), and flow-mediated dilatation of the brachial artery (FMD). One KD patient (9.1%) had persistent coronary aneurysms. There was a significant difference of mean and log-transformed concentrations of hsCRP between case and control groups (2.3 +/- 3.0 vs 0.5 +/- 0.3 mg/l, P = 0.045). None of the patients with elevated hsCRP had persistent coronary arterial lesions. No difference was found in systolic BP z score between the case and control groups. Diastolic BP z score was significantly higher in cases than controls (P = 0.039). There were no significant differences of FMD between cases and controls. Mean fasting total cholesterol, high-density and low-density lipoprotein, and triglycerides in cases were normal, with no significant difference vs controls. This study shows that Chilean children with history of KD have increased levels of hsCRP, possibly reflecting persistent low-grade inflammation. The prognostic value of hsCRP in KD patients deserves further investigation.

Physical activity in the classroom to prevent childhood obesity: a pilot study in Santiago, Chile.

This paper describes a 4-month pilot study that tested the suitability of a physical activity intervention for first graders (children aged 6 and 7 years) in a public school in Santiago, Chile. Teachers were trained to deliver the programme in the classroom during the school day. Teachers were surveyed to determine if this intervention fit within their curriculum and classroom routines and they reported in a focus group that it was suitable for them. All children actively participated in the programme and positive changes in their attitudes towards physical activity were observed by their teachers. Anthropometrics, blood pressure and hand grip strength were measured in the students. A significant reduction was observed in children with high waist circumference ≥ 90th percentile, and in mean systolic blood pressure. However, statistical power values for those comparisons were rather low. Anthropometry and hand grip strength were not modified. The latter calculations and the lack of a control group are showing the weaknesses of this pilot study and that further research with a larger sample size and an experimental design is strongly needed.

Micro-RNAs Let7e and 126 in Plasma as Markers of Metabolic Dysfunction in 10 to 12 Years Old Children.

BACKGROUND: Growing evidence shows that metabolic syndrome (MetS) is already starting in childhood however there is no consensus regarding how to diagnose this condition in pediatric population. Studies in adults show that altered levels of specific micro-RNAs are related with components of the MetS. OBJECTIVE: We determined the plasma levels of four MetS-associated micro-RNAs (miR-126, miR-132, mir-145 and Let-7e) in 10 to 12 years old children with or without MetS traits. DESIGN: Pediatric subjects were selected from a cohort of 3325 school-age children, and clustered by the absence (control, n = 30), or the presence of 1 (n = 50), 2 (n = 41) or 3 (n = 35) MetS traits according to Cook´s criteria. Micro-RNAs were isolated from plasma, and levels of miR-126, miR-132, miR-145 and Let-7e were determined by Taqman qPCR. RESULTS: Regression analysis of the different MetS traits regarding the different miRNAs analyzed showed that Let-7e presented a negative association with HDL-C levels, but a positive correlation with the number of MetS traits. Levels of miR-126 presented a positive correlation with waist circumference, waist to hip ratio, BMI, and plasma triglycerides and VLDL-C. Levels of miR-132 showed a positive correlation with waist to hip ratio. Plasma levels of Let-7e were increased (~3.4 fold) in subjects with 3 MetS traits, and showed significant AUC (0.681; 95%CI = [0.58, 0.78]; p < 0.001) in the ROC analysis which were improved when miR-126 was included in the analysis (AUC 0.729; p < 0.001). In silico analysis of the interaction of proteins derived from mRNAs targeted by Let7 and miR-126 showed an important effect of both Let-7e and miR-126 regulating the insulin signaling pathway. CONCLUSIONS: These results suggest that changes in the plasma levels of Let-7e and miR-126 could represent early markers of metabolic dysfunction in children with MetS traits.

Metabolic syndrome and its components are strongly associated with an inflammatory state and insulin resistance in the pediatric population.

INTRODUCTION: Endothelial inflammation and insulin resistance (IR) begin in childhood and constitute the pathophysiological basis of Metabolic Syndrome (MS). The increase levels in plasma of inflammatory markers such as high sensitive PCR (hsPCR), plasminogen activator inhibitor 1 (PAI-1) and tests suggestive of IR such as Insulin (Ins) and alanine aminotransferase (ALT) have been associated with MS in adults, but have not been studied in children. OBJECTIVES: Correlate the presence of MS and its components with the inflammatory and IR markers seen in the pediatric population. METHODS: Cross-sectional study of 337 children (10,9±9,7 years) whose levels of hsPCR, PAI-1, Ins and ALT were determined, along with their association with MS and its individual components. RESULTS: 37 children had MS (10,4%). The frequency of MS components was: abdominal obesity 38,5%, hypertension (HTN) 21,3%, hypertriglyceridemia 17,8%, HDL 21,3% and hyperglycemia 1,4%. hsPCR, PAI-1, ALT and Ins were higher in the presence of MS and increased progressively when components were came together. CONCLUSIONS: The pediatric population segment with MS had a higher concentration of hsPCR, PAI-1, Ins and ALT.These levels increase proportionally MS components add up, suggesting that even before diagnosis criteria are fulfilled there is a inflammatory state.

La insulino resistencia (IR) y la inflamación endotelial constituyen la base fisiopatológica del Síndrome metabólico (SM) . El aumento de los niveles plasmáticos de mascadores de inflamación como PCRus, Inhibidor del activador de plasminógeni tipo 1 (PAI-1) y parámetros sugerentes de insulino resistencia (IR) como insulina, triglicéridos y Alanino aminotransferasa (ALT) se han asociado a síndrome metabólico en adultos pero han sido menos estudiados en pediatría. Objetivo: Correlacionar los componentes del SM con marcadores de inflamación e IR en población pediátrica. Métodos: Estudio transversal de 337 niños (10,9±9,7 años). Se determinó niveles plasmáticos de PCRus, PAI-1, ALT e Insulina y se evaluó su asociación con Síndrome metabólico y sus criterios de forma individual. Resultados: 37 sujetos tuvieron diagnóstico de SM (10.4%). 38.5% presentó obesidad abdominal, 21.3% Hipertensión arterial, 17.8% Hipertrigliceridemia, 21.3% niveles bajos de HDL y un 1.4% Hiperglicemia. Encontramos que PCRus, PAI-1 y ALT fueron más altas en presencia de SM y aumentaban progresivamente a medida que se agregaban criterios diagnósticos. Conclusión: Este estudio demuestra que en población pediátrica con diagnóstico de SM existen niveles más altos de PCRus, PAI-1, ALT e insulina y que a mayor número de criterios presentes la inflamación pareciera ser mayor lo que sugiere que incluso antes de tener el diagnóstico de SM ya existe un estado pro inflamatorio.

[Effects of tilt test and beta-adrenergic stimulation on the QT interval in normal children and pediatric patients with unexplained syncope]. / Efectos de la prueba de la mesa basculante y de la estimulación betaadrenérgica sobre el intervalo QT en niños sanos y en pacientes pediátricos con síncope de etiología no precisada.

In normal children, any procedure that increases heart rate, such as the tilt test, may shorten the QT interval. The effect of the tilt test on QT interval in children with syncope remains unknown. We analyzed the response of RR and QT intervals during a tilt test in 3 groups of children: 28 healthy children (group 1), 26 with syncope of unknown etiology and negative tilt test results (group 2), and 17 with vasovagal syncope (group 3). During the tilt test, RR and QT intervals were significantly shortened in groups 1 and 2. In group 3, RR interval was lengthened during syncope whereas the QT interval remained constant. QT interval lengthening during the tilt test is not a characteristic finding in normal children or in children with vasovagal syncope.

Associations of prenatal growth with metabolic syndrome, insulin resistance, and nutritional status in Chilean children.

INTRODUCTION: The association of prenatal growth with nutritional status, metabolic syndrome (MS), and insulin resistance (IR) was studied in school-age children. METHODS: A retrospective cohort study was designed linking present data of children with perinatal records. 3325 subjects were enrolled. Anthropometry, blood pressure (BP), and pubertal status were assessed. Blood lipids, glucose, and insulin were measured. Linear associations were assessed using the Cochran-Armitage test. Odds ratios and nonlinear associations were computed. RESULTS: 3290 children (52% females, mean age of 11.4 ± 1 years) were analyzed. Prevalence of obesity, stunting, MS, and IR was 16.0%, 3.6%, 7.3%, and 25.5%, respectively. The strongest positive association was between birth weight (BW) and obesity (OR 2.97 (95% CI 2.01-4.40) at BW ≥ 4,000 g compared to BW 2,500-2,999). The strongest inverse association was between birth length (BL) and stunting (OR 8.70 (95% CI 3.66-20.67) at BL < 48 cm compared to BL 52-53 cm). A U-shaped association between BL and BP ≥ 90th percentile was observed. Significant ORs were also found for MS and IR. Adjustments for present fat mass increased or maintained the most prenatal growth influences. CONCLUSIONS: Prenatal growth influences MS, IR, and nutritional status. Prenatal growth was more important than present body composition in determining these outcomes.

Lactancia materna, obesidad y síndrome metabólico en la edad escolar / Breastfeeding, obesity and metabolic syndrome at school age

INTRODUCCIÓN: La lactancia materna (LM) puede ser un factor protector de la obesidad y sus complicaciones metabólicas. OBJETIVO: Determinar la asociación entre el antecedente de amamantamiento y la presencia de obesidad, síndrome metabólico (SM) y resistencia insulínica (RI). PACIENTES Y MÉTODOS: Estudio transversal en 20 escuelas públicas de Santiago, Chile. Se evaluó antropometría, presión arterial, perfil lipídico, glicemia, insulinemia e índice HOMA. Los padres respondieron una encuesta sobre el antecedente de LM. Se definió SM según criterios de Cook y RI como HOMA > percentil 90. RESULTADOS: Se recibieron 3.278 encuestas válidas. La edad promedio fue de 11,4 ± 1 años, siendo 52,3% mujeres. La mayoría (98,2%) recibió LM, con una prevalencia de 15,9% de obesidad versus 18,6% en los que no la recibieron (p = 0,039). Hubo una tendencia no significativa a que SM y sus componentes, excepto RI, fueran más prevalentes en el grupo no amamantado. Los escolares que recibieron LM por 3-6 meses presentaron una menor prevalencia de obesidad y de algunos componentes de SM que los que recibieron menor tiempo o no la recibieron; el efecto fue inverso cuando la LM se prolongó por más de 9 meses. CONCLUSIONES: La prevalencia de obesidad fue mayor en los escolares que no fueron amamantados. Durante el primer semestre, la LM de mayor duración se asoció a menor prevalencia de obesidad y complicaciones metabólicas.

INTRODUCTION: Breastfeeding (BF) can be a protective factor against obesity and its associated metabolic complications. OBJECTIVE: To determine the association between breastfeeding history and present obesity, metabolic syndrome (MS) and insulin resistance (IR). PATIENTS AND METHODS: Cross-sectio nal study in 20 public schools in Santiago, Chile. Anthropometry and blood pressure were assessed. Blood lipids, glucose, insulin and HOMA index were measured in a fast blood sample. Parents answe red a survey on BF. MS was defined according to Cook's criteria and IR as HOMA > 90th percentile. Parents answered a survey about the antecedent of breastfeeding. Chi2 and Fischer tests were used (SSPS). RESULTS: 3,278 surveys were valid. Average age: 11.4 ± 1 years, 52.3% were female. Most of them (98.2%) were breasted, with a 15.9% prevalence of obesity versus 18.6% in the group that was not breastfed (p = 0.039). There was a non-significant trend of higher prevalence in MS and its components (except IR) in the non-breastfed group. The group breastfed from three to six months had a lower prevalence of obesity and MS components than the 0 to 3 months group ; the effect was the opposite when BF lsted longer than nine months. CONCLUSIONS: The prevalence of obesity was higher in children that did not received breastfeeding. A longer breastfeeding time during the first semester of life was associated with lower prevalence of obesity and metabolic complications.

[Blood lipids in Chilean children 10-14 years of age]. / Niveles de lípidos sanguíneos en escolares chilenos de 10 a 14 años de edad.

INTRODUCTION AND OBJECTIVES: Plasma lipid levels in children and adolescents are evaluated with international references. The objective was to describe them in Chilean students, to compare them with the most used reference (Lipids Research Clinics Program) and the cut-off points recommended in 2011. METHODS: Cross-sectional study in 3325 children, 10 to 14 years of age. Anthropometry and auto-report of pubertal development were performed. A 12 hours fast blood sample was taken to measure total (TC), highdensity lipoprotein cholesterol (HDLC) and triglycerides (TG). Low-density lipoprotein cholesterol (LDLC) was calculated with Friedewald formula. Variables were described, Hochberg test for multiple comparisons and stepwise lineal regression were applied. The degree of agreement between local percentiles and the two international references was studied. RESULTS: We studied 3,063 children, 11.4 ± 0.9 years old, 53% girls, 20.9% pre-pubertal, 22.6% had overweight, and 15.8% obesity. Averages: TC: 159.2 ± 28.3, HDLC: 51.9 ± 12.1, LDLC: 89.0 ± 31.5 and TG: 93.2 ± 60 mg/dL. Boys had higher HDLC: 53.3 ± 12.2 vs. 50.6 ± 11.8 mg/dL and lower TG: 86.2 ± 58.2 vs. 99.5 ± 61.7 mg/dL than girls (p < 0,001). Influences of nutritional status, sex and age were significant. We founded high agreement with the reference for TC and LDLC, but HDLC levels were lower and TG were higher, for their cut-off points: percentiles 10th and 95th, respectively. CONCLUSIONS: Blood lipids were influenced by nutritional status, sex and age. Percentile values were comparable to the international reference except for HDLC and TG, showing a more atherogenic pattern.

Introducción: Las concentraciones de lípidos sanguíneos en niños y adolescentes se evalúan utilizando referencias internacionales. Objetivos: Describir las concentraciones de lípidos sanguíneos en una población de escolares chilenos y compararlas con la referencia más utilizada (Lipid Research Clinics Program) además de los puntos de corte recomendados en 2011. Métodos: Estudio transversal en 3.325 escolares de 10 a 14 años de edad. Se realizó antropometría, auto-reporte de desarrollo puberal y medición en ayunas de colesterol total (CT), colesterol unido a lipoproteínas de alta densidad (CHDL) y triglicéridos (TG). El colesterol unido a lipoproteínas de baja densidad (CLDL) se calculó con fórmula de Friedewald. Se realizó descripción, regresión múltiple y estudio de concordancia. Resultados: Se incluyeron 3.063 niños de 11,4 ± 0,9 años de edad, 53% mujeres, 20,9% pre-púberes; 22,6% con sobrepeso y 15,8% con obesidad. Los promedios fueron: CT: 159,2 ± 28,3, CHDL: 51,9 ± 12,1, LDL: 89,0 ± 31,5 y TG: 93,2 ± 60 mg/dL. Los hombres tuvieron mayor CHDL: 53,3 ± 12,2 vs 50,6 ± 11,8 mg/dL y menor TG: 86,2 ± 58,2 vs 99,5 ± 61,7 mg/dL que las mujeres (p < 0,001). Con regresión múltiple se encontró influencia del estado nutricional y edad en todos los lípidos y del sexo en la mayoría. Comparados con la referencia hubo concordancia en CT y CLDL, pero los niños chilenos presentaron mayores niveles de TG sobre el percentil 50 y menores niveles de CHDL bajo percentil 50. Conclusiones: Las concentraciones de lípidos sanguíneos estuvieron influidas por el estado nutricional, edad y sexo. En comparación a la referencia, se encontró un patrón de mayor riesgo cardiovascular en los niños chilenos.

[Nutritional status, metabolic syndrome and insulin resistance in children from Santiago (Chile)]. / Estado nutricional, síndrome metabólico y resistencia a la insulina en niños de Santiago, Chile.

BACKGROUND: The origin of most non-communicable diseases (NCDs) is in early life. Consequently obtaining information on risk factors for NCDs is important for preventive purposes. However, there is no information available on the prevalence of obesity, metabolic syndrome (MS) and insulin resistance (IR) in Chilean children. OBJETIVES: To determine the prevalence of nutritional status, MS and IR, and secondly, to study the associations among them. METHODS: Cross-sectional study conducted during 2009-2011 in 20 public schools of Puente Alto County, Santiago, Chile. Anthropometry, blood pressure and pubertal status were assessed. A blood sample was obtained for determination of lipids, blood glucose and insulin. Abnormal Homeostasis model assessment index (HOMA-IR) was based on a national standard. RESULTS: 3325 children had a mean age of 11.4 ± 1 years old (range 10-15 years). The prevalence of obesity, MS and IR was 16.1%, 7.3% and 25.9%, respectively. The prevalence of IR and MS was higher in obese children. MS and IR were strongly associated with an OR of 8.0 (95% CI= 5.9-10.7). Multivariate analysis showed that all MS components were associated to IR. CONCLUSIONS: There is a relatively high prevalence of risk factors in this sample of children. The strong positive association between nutritional status, IR and MS points out the need to early identify risk factors for NCDs allowing for prevention.

RESUMEN Introducción: Las principales enfermedades crónicas no transmisibles pueden iniciarse en la niñez, por lo que el conocimiento de sus factores de riesgo puede colaborar en su prevención. No existe información acerca de su prevalencia conjunta en escolares chilenos. Objetivos: Determinar la prevalencia del estado nutricional, síndrome metabólico (SM) y resistencia a la insulina (RI) en escolares, y conocer la asociación entre ellos. Métodos: Estudio transversal en 20 escuelas públicas de la comuna de Puente Alto, Santiago, Chile (2009-2011). Se evaluó antropometría, presión arterial, estado puberal. Se obtuvo una muestra sanguínea para determinar lípidos, glucosa, insulina plasmática. El indice de HOMA, homeostasis model assessment (en español: modelo de evaluación de la homeostasis) se utilizó para estimar RI con un patrón nacional. Resultados: 3325 niños con edad promedio 11,4 ± 1 años (rango 10-15 años). La prevalencia de obesidad, SM y RI fue 16,1%, 7,3% y 25,9%, respectivamente. La prevalencia de RI y SM fue mayor en los obesos. SM se asoció fuertemente a RI: OR: 8,0 (95% CI= 5,9-10,7). El análisis multivariado mostró que todos los componentes del SM se asociaron con RI. Conclusiones: Este estudio realizado en la comuna más poblada de Chile, demostró una alta prevalencia relativa de obesidad, RI y SM en escolares de escuelas públicas pertenecientes a un área de bajos ingresos. La clara asociación positiva demostrada entre estado exceso ponderal, RI y SM, acentúa la importancia de la identificación temprana de los factores de riesgo de ECNT con propósitos preventivos.

[Subclinical atheroesclerosis and metabolic syndrome in children]. / Ateroesclerosis subclínica y síndrome metabólico en niños.

INTRODUCTION: Metabolic syndrome (MS) in children has been associated to subclinical atherosclerosis as estimated by carotid intima-media thickness (CIMT). OBJECTIVES: We aim to ascertain the influence of MS, insulin resistance (IR) and nutritional status on CIMT. Percentiles with an increased risk of CIMT were also explored. METHODS: A cross-sectional study of 447 children attending public schools in Santiago, Chile, was performed during years 2009-2011. This sample was selected considering the presence of one or more MS component and IR. Anthropometry and BP were assessed. A blood sample for determination of glycemia, insulinemia and lipids was taken. CIMT was assessed using high resolution ultrasonography with automated software. Pearson correlation, Student's t-test, Chisquared test, and stepwise logistic regression were computed. RESULTS: Mean age was 11.5 ± 1.0 years old (range 10- 14); 59% girls; 93% pubertal; 72% excess weight; 24% MS; and 15% IR. Mean values of MS components in children with CIMT ≥ percentile 75 versus < percentile 75 had differences for systolic BP or diastolic BP ≥ percentile 90 (BP ≥ percentile 90) and high density lipoproteins cholesterol ≤ 40 mg/dL (CHDL ≤ 40 mg/dL). The logistic regression for CIMT ≥ percentile 75 only selected BP ≥ percentile 90 and CHDL ≤ 40 mg/dL. The logistic regression for CIMT ≥ percentile 90 did not select independent variables. CONCLUSIONS: In this group of children BP ≥ percentile 90 and CHDL ≤ 40 mg/dL values were associated to CIMT ≥ percentile 75. Influences of IR and nutritional status on CIMT were not found.

Introducción: El síndrome metabólico (SM) en niños se ha vinculado al desarrollo de ateroesclerosis subclínica, estimada por el grosor intimo-medial carotideo (CIMT). Objetivos: Estudiar la asociación del CIMT con los componentes del SM, la resistencia insulínica (RI) y el estado nutricional en escolares, además de explorar puntos de corte asociados a riesgo. Métodos: Estudio transversal de 447 niños asistentes a escuelas públicas de Santiago, Chile (2009-2011), seleccionados por presentar uno o más componentes del SM y RI. Se realizó antropometría y toma estandarizada de presión de arteria braquial, además de muestras de sangre para determinar lípidos glicemia e insulinemia. Se midió el CIMT por ultrasonografía de alta resolución. Se utilizó correlación de Pearson, t de Student, chi cuadrado y regresión logística. Resultados: Edad 11,5 ± 1,0 años (rango 10-14); 59% mujeres; 93% púberes; 72% con exceso de peso; 24% con SM y 15% con RI. Los promedios de los componentes del SM en los niños con CIMT ≥?percentil 75 vs < percentil 75 tuvieron diferencias para presión arterial sistólica o diastólica ≥?percentil 90 (PA) y colesterol unido a lipoproteínas de alta densidad =?40 mg/dL (CHDL). En la regresión logística para CIMT ≥?percentil 75 fueron seleccionadas PA y CHDL. En la regresión logística para CIMT ≥?percentil 90 no hubo variables seleccionadas. Conclusiones: En este grupo de niños los niveles de PA y CHDL se asocian con CIMT ≥?percentil 75. No se encontró asociación con estado nutricional y RI posiblemente por ser una muestra seleccionada.

[Waist height ratio, ultrasensitive c reactive protein and metabolic syndrome in children]. / Índice cintura estatura y agregación de componentes cardiometabólicos en niños y adolescentes de Santiago.

BACKGROUND: Waist to height ratio and ultrasensitive C-reactive protein are predictors of the presence of the metabolic syndrome in children. AIM: To determine the proportional risk of metabolic syndrome component clustering in children, using waist to height ratio and ultrasensitive C-reactive protein. MATERIAL AND METHODS: Anthropometric measures, blood pressure, fasting serum lipid profile, blood glucose and ultrasensitive C-reactive protein were determined in 209 children aged 11.5 ± 2 years (50% females). The presence of the metabolic syndrome as a function of waist to height ratio and C-reactive protein was modeled using logistic regression equations. The risk of clustering one, two or more components of the metabolic syndrome was calculated. RESULTS: Metabolic syndrome was present in 5% of all children and 18% of those that were obese. The cut off points for waist to hip ratio and ultrasensitive C-reactive protein were 0.55 and 0.61 mg/L, respectively. For each 0.01 increment in waist to height ratio, the odds ratio of increasing one component of the metabolic syndrome was 1.2 (1.15-1.25) or 15 to 25%. The odds ratio for log-transformed ultrasensitive C-reactive protein was 1.62 (1.26-2.09). Excluding waist circumference, the odds ratio of adding one or more components of the metabolic syndrome was 1.05 (1.01-1.09) per 0.01 increment in waist to height ratio, but the odds ratio for C-reactive protein was no longer significant. CONCLUSIONS: Waist to height ratio and ultrasensitive C-reactive protein predict the risk of clustering components of the metabolic syndrome in these children.

[Association between a cardiovascular risk score and early markers of atherosclerotic disease in Chilean children]. / Validación de un puntaje de riesgo cardiovascular en niños españoles aplicado a una población de escolares de Santiago de Chile.

BACKGROUND: A cardiovascular risk score for children, that includes traditional risk factors, obesity, sedentary habits and a family history of cardiovascular disease, has been recently proposed by Spanish researchers. AIM: To apply this score in school age children in Santiago de Chile and correlate its results with markers of subclinical atherosclerotic disease. MATERIAL AND METHODS: Retrospective analysis of data obtained from 209 children, aged 11.5 ± 2 years, studied between 2005 and 2006. Weight, height, blood pressure, ultrasound measurement of carotid intimamedia thickness and fow mediated dilatation of brachial artery and ultrasensible C reactive protein (us PCR) were measured. The Spanish cardiovascular risk score was calculated and correlated with ultrasound parameters and C reactive protein. RESULTS: According to the score, 173 children (83%) had a low cardiovascular risk, 28 (13%) an intermediate risk and 8 (4%) a high risk. There was no association between the cardiovascular risk score and carotid intima-media thickness, fow mediated arterial dilatation and us PCR. CONCLUSIONS: No significant association was observed between the proposed cardiovascular risk score and early markers of atherosclerotic disease in this group of children.