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

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 ± 0.9years (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 CIMTover 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) perfive units of change, respectively. Conclusions: In this group of children systolic blood pressure and HDL cholesterol are associated to CIMT.

Insulinemia e índice HOMA en niños y adolescentes chilenos / Normal plasma insulin and HOMA values among chilean children and adolescents

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 μϋ/mL (p < 0.01) and 2.7 ± 1.4 and 2.1 ± 1,1 (p < 0.01), respectively). Subjects with Tanner I and IIpuberal stages had lower insulin and HOMA mean values than subjects with Tanner III and IV (9.0 ± 4.3 and 12.5 ± 6.2μϋ/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.

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

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 percent) had a low cardiovascular risk, 28 (13 percent) an intermediate risk and 8 (4 percent) 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.

Marcadores de aterosclerosis temprana y síndrome metabólico en niños / Early markers for atherosclerosis and metabolic syndrome in children

Background: The high prevalence of obesity in children favors the appearance of metabolic syndrome (MS), increasing their cardiovascular risk. Aim: To evaluate components of MS in children and to correlate them with surrogate markers of atherosclerosis andsubclinical inflammation. Material and methods: We studied 209 children aged 11.5 ± 2 years (50% girls, 30% prepuberal). Fifty percent had normal weight, 18% were overweight, 29% were obese and 3% were undernourished. A fasting blood sample was obtained to measure lipid levels,glucose, insulin, adiponectin and ultrasensitive C-reactive protein (usCRP). Subclinical atherosclerosis was evaluated using flow mediated dilatation of brachial artery (FMD) andcarotid intima-media thicknes (IMT). For diagnosis of MS we adapted Cook’s criteria. Results: Five percent of all children and 18% of those with overweight had MS. Children with more components had significantly higher fasting insulin and Homeostasis Model Assessment (HOMA) values. Clustering of MS components was also associated to higher values of usCRP and non significantly to lower adiponectin levels. We did not find differences in FMD. In obese children there was a tendency towards a higher IMT with clustering of MS components, although not significant. Conclusions: Children with overweight presented a higher risk of a clustering ofMS components, which was also associated with insulin resistance and increase in ultrasensitive C reactive protein.

Proteína C-reactiva y su relación con adiposidad, factores de riesgo cardiovascular y aterosclerosis subclínica en niños sanos de la Región Metropolitana / C-reactive protein in relation to adiposity, cardiovascular risk factor and subclinical atherosclerosis in healthy children from Santiago, Chile

Introducción: La proteína C-reactiva ultrasensible (PCRus) es un marcador de riesgo (FR) emergente. En adultos, se asocia a la mayoría de los FR metabólicos, al desarrollo de diabetes y predice eventos cardiovasculares futuros. Dado que la aterosclerosis puede comenzar en la niñez, es importante conocer los niveles de este marcador y sus relaciones con los FR clásicos en la población pediátrica. Objetivo: Determinar los niveles de PCRus y establecer su relación con medidas antropométricas de adiposidad, FR tradicionales y medidas de aterosclerosis subclínica en niños de Santiago. Método: Estudio prospectivo en hijos de sujetos sanos de la zona urbana de Santiago. En todos los niños se realizó una encuesta sobre FR clásicos, se evaluó antropometría, maduración puberal y perfil lipídico, glicemia y PCR ultrasensible (Dade Behring) en muestra de sangre en ayunas. En todos se realizó además estudio de función endotelial por dilatación mediada por flujo en arteria braquial (DMF) y del grosor íntima-media carotídeo (IMT). Resultados: Se incluyeron en este análisis 88 niños (51 por ciento hombres), edad 10 +/- 2 (promedio DS) años. La PCRus del grupo fue 0.88 +/- 1.47 mg/L (mediana = 0.38 mg/L). En ambos sexos, la PCRus se correlacionó en forma directa a índice de masa corporal (IMC, expresado en puntaje z), a estimación clínica de grasa corporal: masa grasa total (MGT), grasa troncal, perímetro de cintura (PC) y a colesterol LDL (p<0.04). Los niños en el tercil superior de PCR presentaron mayor: zIMC, MGT, PC y LDL que los niños en los terciles inferiores (ver tabla). Los factores de riesgo para determinar una PCR elevada, en forma aislada, fueron: zIMC (OR=2.25 {1.25-4.04}), MGT (OR=1.09 {1.03-1.15}) y PC (OR=1.06 {1.01-1.11}). No se demostró asociación entre PCRus y DMF o IMT. Conclusión: La PCRus se asocia en forma directa a índices de adiposidad y a colesterol LDL en niños...

Background: Ultrasensitive C-reactive protein (USCRP) is an emergent cardiovascular risk factor (RF). In adults, USCRP is associated to most metabolic RF, to diabetes and future cardiovascular events. Since atherosclerosis may develop in childhood, the relation of USCRP to classic RF in children deserves attention. Aim: To correlate USCRP levels with adiposity, traditional RF and subclinical atherosclerosis in children from Santiago Methods: Children from healthy parents living in urban areas of Santiago were prospectively studied. A survey of traditional RF, anthropometric measurements, pubertal maturation, serum lipid profile, serum blood sugar level and USCRP (Dade Behring) were determined in all children in a fasting sample. Endothelial function was assessed by flow mediated vasodilation of the brachial artery (FMD) and intimal media thickness (IMT) Results: 88 children (51 percent males) aged 10 +/-2 years were studied. Mean USCRP was 0.88 mg/L(SD 1.47, median 0.38). In both gender groups USCRP was directly correlated to body mass index (BMI, z score), total body fat (TBF) , central adiposity measured by skin folds, waist circumference (WC) and LDL cholesterol (p<0.04). Children at top tercile USCRP level exhibited greater BMI, total body fat, central adiposity, WC and LDL level as compared to those in the lower USCRP tercile (Table). Independent predictors of high CRP levels were BMI (OR 2.55, 95 percent CI1.25-4.04), MGT (OR 1.09 (1.03-1.15)) and WC (OR 1.06 (1.01-1.11)). There was no association between USPCR and FMV or IMT. Conclusion: USCRP is directly associated to adiposity indices and serum LDL level in children. This study showed no association of USCRP and indices of subclinical atherosclerosis. Follow up of these children will help determine whether subclinical inflammation will predict the appearance of atherosclerosis when they reach adult age.