Bárbara Leyton

School-based obesity prevention in Chilean primary school children: methodology and evaluation of a controlled study.

OBJECTIVE:To assess the impact of a 6 months nutrition education and physical activity intervention on primary school children through changes in adiposity and physical fitness.DESIGN: Longitudinal school-based controlled evaluation study.SUBJECTS: Children from 1st to 8th grade, 2141 in intervention and 945 in control schools.INTERVENTION: Nutrition education for children and parents, ‘healthier’ kiosks, 90 min of additional physical activity (PA) weekly, behavioral PA program and active recess.MEASUREMENTS: Adiposity indices (BMI, BMI Z-score, triceps skinfold thickness (TSF), waist circumference and physical fitness (20 m shuttle run test and lower back flexibility).RESULTS: Positive effect on adiposity indices (except TSF) was observed in boys (P<0.001 for BMI Z), while both physical fitness parameters increased significantly in both boys (P<0.001 for each test) and girls (P<0.0001 for each test). A differential effect in BMI Z was observed according to baseline nutritional status.CONCLUSIONS: This intervention showed a robust effect on physical fitness in both genders and decreased adiposity only in boys.

Two-year controlled effectiveness trial of a school-based intervention to prevent obesity in Chilean children

OBJECTIVE Obesity prevalence among Chilean children is 19.4%. The present study aimed to assess the effectiveness of a school-based obesity prevention programme. DESIGN Non-randomized controlled study. The intervention included activities in nutrition and physical activity, fully applied the first year and partially in the second one. Primary outcomes were BMI Z-score (BMIZ) and obesity prevalence; secondary outcomes were waist circumference and triceps skinfold thickness. Time effects were assessed by changes in BMI-related variables by gender and period (ANOVA and Tukey test), while intervention effects were determined by comparing changes in (i) obesity prevalence by gender and period (PROC GENMOD) and (ii) BMIZ according gender, age and period (PROC MIXED). SETTING Primary schools in the Chilean cities of Casablanca (intervention group) and Quillota (control group). SUBJECTS One thousand seven hundred and fifty-nine children from three schools (intervention group) and 671 from one school (control group). RESULTS Over the two years, obesity prevalence and BMIZ declined significantly in the intervention group; from 17.0% to 12.3% and 14.1% to 10.3% in boys and girls, respectively, and from 0.62 to 0.53 and 0.64 to 0.58, respectively. In the control group, obesity remained stable at about 21% and 15%, while BMIZ increased significantly in the second year. BMIZ declined in both genders and all age categories in the intervention group during the first year (significant only in younger boys). No changes occurred during the summer, while during the second year, BMIZ increased in boys and girls from both groups (significant only in the younger control boys). Obesity declined significantly only in boys during the first year. CONCLUSION Effectiveness was greater in the first school year and more evident in younger boys.

Estrategia de prevención de obesidad en escolares: Efecto de un programa aplicado a sus profesores (2007-2008)

Background: In 2007, a preventive strategy for childhood obesity, that included food education and an increase in physical activity, was implemented in seven public schools located in Santiago. In four of these schools, a counseling program about healthy lifestyles for teachers was also carried out. Aim: To test if counseling had an effect in the intervention for children. Material and Methods: Anthropometric measures were assessed in children at baseline and after two years of intervention. Teachers were also evaluated with anthropometry and a blood sample was obtained to measure blood glucose and serum lipids. Results: Four hundred twelve children from schools whose teachers had counseling and 237 children from schools whose teachers did not have it were evaluated. Twenty-eight teachers with and 19 with no counseling were assessed. In children, the overall prevalence of obesity decreased from 20.2 to 18.3% (p = 0.03). This reduction was only significant among females. BMIZ score decreased significantly in children of both genders. No effect of counseling was observed on weight reduction. Among teachers that received counseling, the prevalence of obesity decreased from 25 to 22.4%, with significant improvements in blood glucose and HDL cholesterol. Conclusions: Counseling directed at teachers did not improve the effect of a program to reduce obesity among schoolchildren.

School-based obesity prevention intervention in Chilean children: effective in controlling, but not reducing obesity.

Objective. To evaluate the effectiveness of a 12-month multicomponent obesity prevention intervention. Setting. 9 elementary schools in Santiago, Chile. Subjects. 6–8 y old low-income children (). Design. Randomized controlled study; 5 intervention/4 control schools. We trained teachers to deliver nutrition contents and improve the quality of PE classes. We determined % healthy snacks brought from home, children’s nutrition knowledge, nutritional status, duration of PE classes, and % time in moderate/vigorous activity (MVA). Effectiveness was determined by comparing BMI between intervention and control children using PROCMIXED. Results. % obesity increased in boys from both types of schools and in girls from control schools, while decreasing in girls from intervention schools (all nonsignificant). % class time in MVA declined (24.5–16.2) while remaining unchanged (24.8–23.7%) in classes conducted by untrained and trained teachers, respectively. In boys, BMI declined (1.33–1.24) and increased (1.22–1.35) in intervention and control schools, respectively. In girls, BMI remained unchanged in intervention schools, while increasing significantly in control schools (0.91–1.06, ). Interaction group time was significant for boys () and girls (). Conclusions. This intervention was effective in controlling obesity, but not preventing it. Even though impact was small, results showed that when no intervention is implemented, obesity increases.

Twelve-year follow-up study of the impact of nutritional status at the onset of elementary school on later educational situation of Chilean school-age children

Objective:To determine the impact of nutritional status in a multicausal approach of socio-economic, socio-cultural, family, intellectual, educational and demographic variables at the onset of elementary school in 1987 on the educational situation of these children in 1998, when they should have graduated from high school.Setting:Chiles Metropolitan Region.Design:Prospective, observational and 12-year follow-up study.Methods:A representative sample of 813 elementary first grade school-age children was randomly chosen in 1987. The sample was assessed in two cross-sectional studies. The first cross-sectional study was carried out in at the onset of elementary school in 1987 and the second was carried out in 1998, 12-years later, when they should be graduating from high school. In 1998, 632 adolescent students were located and their educational situation was registered (dropout, delayed, graduated and not located). At the onset of elementary school were determined the nutritional status, socio-economic status (SES), family characteristics, intellectual ability (IA), scholastic achievement (SA) and demographic variables. Statistical analysis included variance tests and Scheffes test was used for comparison of means. Pearson correlation coefficients and logistic regression were used to establish the most important independent variables at the onset of elementary school in 1987 that affect the educational situation 1998. Data were analysed using the statistical analysis system (SAS).Results:Logistic regression revealed that SES, IA, SA and head circumference-for-age Z score at the onset of elementary school in 1987 were the independent variables with the greatest explanatory power in the educational situation of school-age children in 1998.Conclusions:These parameters at an early school age are good predictors of the educational situation later and these results can be useful for nutrition and educational planning in early childhood.Sponsorship:This study was supported in part by Grants 1841167 and 1880818 from the National Fund for Scientific and Technologic Development (FONDECYT), Grants S 2169-924F and EO11-97/2 from the University of Chile, Research Department (DI), and by Grant 019/1997 from the University of Chile, Postgradest Department.

Anthropometric characteristics and physical fitness level in relation to body weight status in Chilean preschool children

The purpose of this study was to describe anthropometric and physical fitness characteristics of low-income Chilean preschool children and to examine whether weight status influences childrens performance on fitness tests. A total of 434 preschool children (246 boys; 5.48 ± 0.31 years) participated in our study. Anthropometry (weight, height, body mass index -BMI- and waist circumference) and fitness tests (handgrip strength test, standing long jump and 20 m sprint) were assessed by trained nutritionists and physical education teachers, respectively. Significant differences in anthropometry and fitness tests between boys and girls were found. The prevalence of overweight was higher in girls; in contrast to that of obesity. Compared to normal-weight children, overweight/obese boys and girls were heavier and had greater waist circumference (P < 0.001), were taller (P ≤ 0.002), and showed higher performance in handgrip strength (P ≤ 0.027) but not in standing long jump nor 20 m sprint (P ≥ 0.052). Screening physical fitness levels in overweight/obese preschool children could be an important tool in order to design an efficacy physical activity programme.

Association between Socioeconomic Vulnerability and Height with Obesity in Low-Income Chilean Children in the Transition from Preschool to First Grade

This study determined the percentage of obesity among lower-income Chilean children 4–6 years of age, by socioeconomic vulnerability (family score assessing the children’s risk of becoming poor) and height. The sample included 17,080 children with anthropometry at 4, 5, and 6 years of age, and three categories of socioeconomic vulnerability. Body mass index Z-score (BMI Z), % obesity, height/age Z-score (HAZ) by socioeconomic vulnerability/sex, the effect of socioeconomic vulnerability on BMI Z and HAZ by age/sex, and BMI Z and % obesity at 4–6 years, according to initial height, were determined. Between 4–6 years, % obesity is very high, especially among the less-vulnerable and taller children. Preventive measures should prioritize this group.

Case study of complaints on drinking water quality: relationship to copper content?

Several families of Talca city, Chile complained to health authorities for what they attributed to consumption of copper (Cu)-contaminated drinking water. We assessed the situation 6–12 mo after the initiation of complaints by characterizing the symptoms reported, the chemistry of drinking water, and the Cu concentration in stagnant drinking water. After completing a census, 1778 households accepted participation and were categorized as follows: category 1, Cu plumbing for tap water and dwellers reporting health complaints (HC); category 2, Cu plumbing for tap water and dwellers reporting no HC; category 3, plastic plumbing for tap water and dwellers reporting no HC. Questionnaires recorded characteristics of households and symptoms presented by each member of the family in the last 3 mo. The Cu concentration in drinking water was measured in a subsample of 80 homes with Cu pipes. In category 1, participants presented significantly more abdominal pain, diarrhea, and/or vomiting (gastrointestinal [GI] symptoms) in comparison to category 3 and to categories 2 plus 3. The stagnant Cu concentrations measured in drinking water in all houses studied were below the US Environmental Protection Agency guideline value (<1.3 mg Cu/L). In summary, data obtained by interviews suggested that individuals in some areas of Talca city were suffering more GI symptoms potentially related to Cu excess, but measurement of Cu concentration in stagnant tap waters ruled out the association between Cu exposure and GI symptom reports at the time of this study. The dose-response curves for GI symptoms and Cu exposure now available were crucial in the analyses of results.

Impact of a school-based intervention on nutritional education and physical activity in primary public schools in Chile (KIND) programme study protocol: cluster randomised controlled trial

BackgroundChile has suffered a fast increase in childhood obesity in the last 10 years. As a result, several school programmes have been implemented, however the effectiveness of these needs to be evaluated to identify and prioritize strategies to curve this trend.MethodsCluster randomized controlled trial. Twelve primary public schools chosen at random over three regions of the country will take part in this study. The sample size consisted of a total of 1,655 children. For each region one school will be selected for each of the three nutritional intervention modes and one school will be selected as the control group. The intervention modes consist of the following:Healthy Kiosk and nutritional education (KSEAN);Optimized physical activity (AFSO);Healthy Kiosk and nutritional education (KSEAN) + optimized physical activity (AFSO);Control group.The effectiveness of each intervention will be evaluated by determining the nutritional condition of each child by measuring percentage of body fat, BMI and the z-score of the BMI. This study will also identify the eating behaviours, nutritional knowledge and fitness of each child, along with the effective time of moderate activity during physical education classes.DiscussionA protocol to evaluate the effectiveness of a school based intervention to control and/or reduce the rates of childhood obesity for children between 6 and 10 years of age was developed. The protocol was developed in line with the Declaration of Helsinski, the Nüremberg Code and the University of Chile Guidelines for ethical committees, and was approved by the INTA, Universidad de Chile ethical committee on Wednesday 12 March 2014.There is consensus among researchers and health and education personnel that schools are a favourable environment for actions to prevent and/or control childhood obesity. However a lack of evidence on the effectiveness of interventions to date has led some to question the wisdom of allocating resources to programmes. This is the first study of this kind in Chile and could be an important first step to provide guidance to political authorities in relation to which food and nutrition strategies to prioritize to curve this alarming trend.Trial registrationISRCTN32136790, registered retrospectively on 05 September 2014.

Chilean School-Age Children Twin Registry: Planning, Sampling and Implications

We describe subject recruitment from the University of Chile School-Age Children Twin Registry (REMEUCHI). The research aim of (REMEUCHI) is to quantify the impact of genetic and environmental factors on scholastic achievement in a multicausal approach. The Ministry of Education of Chile, in collaboration with the Registry Office, provided the list of possible twin pairs graduated from high school in 2004 in Chiles metropolitan region. From a population of 70,065 school-age children who had graduated from high school, 434 possible twin pairs were analysed. Of these, 327 were twins reared together (75.3% of the 434 possible twins pairs) and born between 1986 and 1987 in Chile (mean age 18 years), and approximately 8% were not twins despite matches on full name and birth data. The rest of the possible twin pairs were probably twins reared apart, since one member of the pair had moved to study in another region of Chile. Zygosity was determined through questionnaires, maternal reports of twin similarities, and by the hospital records of the twins at the time of birth. Three hundred and twenty-seven pairs were identified, where monozygotic (MZ) and dizygotic (DZ) twins represented 46.8% and 53.2% of pairs, respectively, with a DZ/MZ ratio of 1.14. Considering same-sex MZ pairs, the percentage of female pairs was greater (55.6%) than male pairs (44.4%). When DZ pairs were analyzed, 47.7% were of opposite sex, 20.1% were male pairs and 32.2% female pairs. In Chile, these findings represent a baseline study to contribute to the establishment of a national twin registry in the future.