Raquel Burrows A

Síndrome metabólico en niños y adolescentes: asociación con sensibilidad insulínica y con magnitud y distribución de la obesidad

Descriptive study in 489 children (273 females), aged from6 to 16 years, consulting in an obesity program. Body mass index, Tanner puberal development, waistcircumference, blood pressure, fasting blood glucose, insulin and lipid levels were measured. Insulinsensitivity was calculated using the mathematical models QUICKI and HOMA. MS was diagnosedwhen three or more of the following criteria were met: a waist circumference over percentile 90, ablood pressure over percentile 90, serum triglycerides over 110 mg/dl, HDL cholesterol of less than 40mg/dl or a fasting blood glucose level over 100 mg/dl.

Hábitos de ingesta y actividad física en escolares, según tipo de establecimiento al que asisten

Background: The increased infantile obesity rates are related to faulty dietary intake (DI) and physical activity (PA) habits, that are probably related to a prolonged stay at school during the day. Aim: To investigate DI and PA among elementary and high school students and their association with type of school that they attend. Material and Methods: Quality of DI and PA was assessed, using specially designed questionnaires, in 1136 elementary school and 1854 high school children attending public schools managed by city halls (ME), subsidized private (SE) and private (PE) of the Metropolitan Region. The responses to the questionnaires, were qualified using a numeric scale that ranged from 0 to 10 points. A higher score indicated a better habit. Results: Percentile 25 (p 25 th) PA score was 4 and 3 in elementary and high school children respectively and the p 25 th for DI were 5.7 and 4.3, respectively. No differences in DI scores, according to the type of school, were observed. However, physical activity scores were significantly lower in children and adolescents from ME schools than from PE schools. Sixty percent of ME schools had less than 2 hours per week of programmed physical activity compared to more than 3 hours, in 70% of PE schools. Elementary school children and high school adolescents expended 8 and 11 hours per day, respectively, in minimum expenditure activities. Conclusions: There is a greater deterioration of PA than DI among school age children and adolescents. Those attending ME schools have the worst physical activity scores. This fact must be addressed in future healthy lifestyle encouragement policies (Rev Med Chile 2008; 136: 53-63). (Key words: Child behavior; Child preschool; Exercise)

Valor de un test clínico para evaluar actividad física en niños

One hundred eighty children aged 8 to 13 years answered aninterviewer-administered questionnaire about their usual PA, consisting in 5 items (recumbent,seated, walking, playing outdoor, sports). The answers were converted to a PA score with a 0-10points scale. Reliability was tested in 87 children by test/retest conducted 3-5 days apart. The PAscore was compared with 3-day accelerometry in 77 of 93 children (35 obese and 42 nonobese). Receiver operating characteristic (ROC) curves were used to determine the optimal cut-point for identify an excessively sedentary child.

Variaciones del índice de masa corporal (IMC) de acuerdo al grado de desarrollo puberal alcanzado

BACKGROUND Body mass index (BMI) is the recommended parameter to assess the nutritional status of subjects aged less than 20 years. However, during puberty the correlation between BMI and fat mass decreases notably. Therefore, the use of BMI for the diagnosis of obesity during puberty may be misleading. AIM To evaluate the variations of the BMI during puberty according to chronological and biological ages. MATERIAL AND METHODS Descriptive cross sectional study in school age children of elementary and high schools (4,531 males and 5,326 females) representing all socioeconomic strata of 4 regions of Chile. BMI was calculated from weight and height measurements (W/H2) and pubertal development was evaluated according to Tanner stages. The sample selected to evaluate the variations of BMI according to chronological age and pubertal stages consisted in 3,913 females aged 8-14 years and 2,494 males aged 10-16 years. Analyses of variance (F test) and Tukey HSD test were used to compare mean BMI according to chronological and biological ages. RESULTS The age of onset of puberty (Tanner Stages IB2 and G2) varied greatly, from 8 to 14 years in females and 10 to 16 years in males. Mean BMI in a specific stage of pubertal development did not show significant differences according to age in both sexes. However, there were significant differences (p < 0.05) in mean BMI when comparing children of the same chronological age but in different Tanner stages. Per each stage of Tanner development, BMI increased 1.0 or more points among females and 0.6 points among males. CONCLUSIONS During puberty, BMI is associated to biological and not chronological age.

Perfil metabólico de riesgo cardiovascular en niños y adolescentes obesos con menor sensibilidad insulínica

Infantile obesity is associated with metabolicdisturbances (hiperinsulinism, impaired glucose, dislypidemia) that determine a higher risk oftype 2 diabetes, high blood pressure and atherosclerotic vascular disease in adulthood. Insulinresistance is a central mechanism of complications of obesity and is associated to body fat mass.

Prevención y tratamiento de la obesidad desde la niñez: la estrategia para disminuir las enfermedades crónicas no transmisibles del adulto

The prevalence of obesity among children and teenagers is increasing by 1.5% per year, probably due to a higher consumption of highly caloric foods and to physical inactivity. Hypercholesterolemia, increased insulin levels and high blood pressure of childhood obesity, precede atherosclerosis, coronary artery disease, diabetes and hypertension in adulthood. The prevention of childhood obesity is an efficient strategy to decrease the prevalence of non transmissible chronic diseases in the adult. The recommendations of experts committees for the prevention, diagnosis and treatment of childhood obesity are reviewed. They aim at a change in dietary habits and increasing physical activity. A well balanced healthy diet and a decrease in physical inactivity time will result in a successful treatment approach for obesity. (Rev Med Chile 2000; 128: 105-110)

Características biológicas, familiares y metabólicas de la obesidad infantil y juvenil

Obesity is the most prevalent nutritional disease in people of less than 20 years old. Aim: To report biological, familial and metabolic characteristics in obese children. Patients and methods: A retrospective review of 187 children seen at obesity clinics and that had a complete metabolic study. Results: Ninety five prepuberal and 92 puberal children, aged 8.7±2.2 and 12.6±2.2 years old respectively, were studied. Body mass index was over 4 standard deviations in 48.4% of prepuberal children and in 39.1% of puberal children. Paternal obesity was twice more prevalent (30.2%) than in the general population. The daily caloric intake and basal metabolic rate (BMR) were within the normal range; nevertheless there was a positive caloric balance due to minimal physical activity. The mean daily fat intake was normal (26.4±8.5 and 25.3±9.1% of total calories in prepuberal and puberal children respectively). The daily fiber intake was under 70% of recommendation. The total cholesterol was over 200 mg/dl in 26.6 and 23.9% of prepuberal and puberal children. LDL cholesterol was over 130 mg/dl in 27.3 and 26.6% and triacylglycerol was over 150 mg/dl in 16.9 and 25% of prepuberal and puberal children respectively. Basal serum insulin was over 20 uIU/ml in 27.7 and 42.2% of prepuberal and puberal children, respectively. Post glucose serum insulin was over 60 uIU/ml in 40 and 63% of prepuberal and puberal children, respectively. Conclusions: Infantile and juvenile obesity is a chronic disease with a high incidence of metabolic alterations (Rev Med Chile 2001; 129: 1155-62)

Sensibilidad insulínica en niños de 6 a 15 años: asociación con estado nutricional y pubertad

Body mass index (BMI), totalbody fat percentage (%TBF) using the sum of 4 skin folds, abdominal obesity determined throughwaist circumference (WC), pubertal maturation using five Tanner stages, fasting glucose (Glu) andinsulin (Ins), were measured in 354 children aged 6 to 15 years (173 males). IS was evaluatedusing HOMA and QUICKI.

Ingesta y metabolismo energético en una muestra de adolescentes chilenos con sobrepeso y obesidad

Background In the last decades, a seven to nine fold increase in the prevalence of teenage obesity and overweight has occurred. Aim To assess energy intake and metabolism in a sample of overweight and obese adolescents. Material and methods In a sample of 113 overweight and obese Chilean adolescents (aged 13 to 16 years, 67 females) we studied anthropometry, body composition by deuterium isotope dilution water, resting energy expenditure by indirect calorimetry and 24-h diet and physical activity recalls. Results Most participants (87% of men and 67.2% of women) had an intake that was adequate compared to requirements (fAO/WHO 2005). However, 82.6% of men and 83.6% of women showed reduced energy expenditure. The sample was classified as sedentary, with a physical activity level of 1.29. Conclusions In our sample of overweight and obese adolescents there was a sedentary behavior, resulting in low energy expenditure that would explain a sustained caloric retention. Preventive and therapeutic interventions should encourage the increase in physical activity.

Consenso sobre el diagnóstico y tratamiento de la pubertad precoz central

The beginning of puberty is marked by breast growth in girls and testicular enlargement in boys. These occur at the age of 10.5 ± 2.0 years in females and 11.5 ± 2.0 years in males. Recent but controversial publications suggest that these events are being observed at younger ages, at least in the USA. There are no studies demonstrating that this is true in Chile. For this reason we still consider that puberty is precocious when it occurs before 8.0 years in girls and before 9.0 years in boys. True or central precocious puberty (CPP) must be distinguished from peripheral or pseudoprecocious puberty (PPP), from premature telarche and from premature adrenarche. We suggest that the workup of a patient with premature development should include an LHRH test to demonstrate if the hypothalamic-pituitary axis is activated, plasma levels of sex steroids, bone age and pelvic ultrasound in girls. All children with CPP should have a CAT scan or MNR of the brain, since a lesion of the central nervous system is observed in 15% of the girls and 50% of the boys whith CPP. Additional studies are needed in cases of PPP. The aim of treating CPP is to avoid adult short stature that results from premature fusion of the epiphysis and to avoid eventual emotional and psychological stress. Treatment consists of monthly intramuscular injections of a depot preparation of LHRH analogs. Suppression of pituitary and gonadal activity produces regression of secondary sex characteristics and slowing down of growth velocity and bone maturation. The opportunity, duration of treatment and their effect on final stature are discussed (Rev Med Chile 2003; 131: 95-110)