Update on the metabolic syndrome in children

Correlating neighborhood-level deprivation and pediatric metabolic dysfunction-associated steatotic liver disease

OBJECTIVES

The primary objective of this study is to further explore associations between social influencers of health and markers of disease severity at the time of presentation of patients with pediatric metabolic dysfunction-associated steatotic liver disease (MASLD) using neighborhood-level Area Deprivation Index (ADI) scores.

METHODS

A retrospective cross-sectional study was conducted among 344 pediatric MASLD patients. Each patient received an ADI score based on their 9-digit zip code. Groups were defined as low (≤5) and high (6≥) ADI. Associations between ADI and symptomatology and laboratory values at presentation, as well as initial liver biopsy pathology were tested via analyses of covariance, χ2 testing, and logistic regressions.

RESULTS

The mean ADI was 6.54 (standard deviation = 2.09). ADI groups did not significantly differ in age of presentation, type of presentation, or associated conditions, except for the higher ADI group having on average lower vitamin D levels (26.70 vs. 29.91, p = 0.02) and being two times more likely to also be diagnosed with low high-density lipoprotein (HDL) levels (p = 0.04, 95% CI 1.04-3.89). Mean transaminases and histopathologic nonalcoholic fatty liver disease (NAFLD) Activity Scores did not significantly differ between ADI groups.

CONCLUSIONS

Pediatric patients with MASLD in this study span the entire spectrum of neighborhood deprivation. There were no differences in presentation characteristics or severity of MASLD, aside from lower HDL-cholesterol and vitamin D values in the high ADI group. Area deprivation was not predictive of more severe disease as assessed by serum transaminases and liver biopsy NAFLD activity scores.

Reproducibility and relative validity of a semiquantitative food frequency questionnaire in European preschoolers: The ToyBox study

OBJECTIVES

The aim of this study was to examine the reproducibility and relative validity of a semiquantitative food frequency questionnaire (FFQ) in assessing food group estimates.

METHODS

Food group estimates were assessed via a 37-item FFQ and a 3-d food record (FR). Pearson's correlation coefficients for log-transformed values were calculated to assess the reproducibility and Spearman's rank correlation coefficients for log-transformed values were calculated to assess the validity. Kindergartens from six European countries participated in the preparatory substudies of the ToyBox intervention study; data from preschool children 4 to 6 y of age (n = 196, reproducibility study; n = 324, validation study) were obtained.

RESULTS

In the reproducibility study, positive Pearson's correlation coefficients for single and aggregated food groups ranged from 0.14 for pasta and rice to 0.90 for cooked vegetables. In the validation study, the FR gave higher estimates of 40 of the 50 food items (single and aggregated) examined compared with those obtained from the FFQ. Positive crude Spearman rank correlation coefficients ranged from 0.01 for total beverages (added sugar) and rice to 0.62 for tea. Corrections for the deattenuation effect did not improve observed correlations. Quartiles and tertiles were calculated for a small number of food groups (N = 14) owing to zero consumption in the rest of the groups.

CONCLUSIONS

Moderately good reproducibility and low-moderate relative validity of the FFQ used in preschool children was observed. Relative validity, however, varied by food and beverage group; for some of the "key" foods/drinks targeted in the ToyBox intervention (e.g., biscuits), the validity was good. The findings should be considered in future epidemiologic and intervention studies in preschool children.

Association between Physical Fitness and Cardiometabolic Risk of Children and Adolescents in Korea

Background

This study aimed to investigate the association between physical fitness and cardiometabolic health of Korean children and adolescents.

Methods

In total, 168 participants (89 boys and 79 girls) aged 10–16 years were recruited for the Intervention for Childhood and Adolescent Obesity via Activity and Nutrition Study in 2016. The subjects were categorized into two groups using the definition of metabolic syndrome by the International Diabetes Federation: metabolically unhealthy (with at least two of the five criteria) and healthy groups (with less than one criterion). Correlation analysis of the participants’ general characteristics was performed. Odds ratios (ORs) of physical fitness for cardiometabolic risk were evaluated via logistic regression.

Results

Metabolically unhealthy children showed greater weight, height, and body mass index, higher Children’s Depression Inventory score, and longer screen time than did the metabolically healthy children. Metabolically healthy children showed greater upper and lower extremity muscular strength than did the metabolically unhealthy children (P=0.04 and P<0.001, respectively). In the multiple logistic regression analysis, lower extremity muscle strength was inversely related to the clustered cardiometabolic risk of the children and adolescents with or without adjustment for confounders (OR, 4.32; 95% confidence interval [CI], 1.87–9.97; OR, 7.64; 95% CI, 1.55– 37.74, respectively).

Conclusion

Physical fitness, especially lower extremity muscle strength, is significantly inversely associated with individual and clustered cardiometabolic risks in Korean children and adolescents.

Threat vigilance and socioeconomic disparities in metabolic health

A quarter of the global population meets diagnostic criteria for metabolic syndrome (MetS). MetS prevalence stratifies by socioeconomic status (SES), such that low SES is associated with higher MetS risk starting in childhood. Despite this trend, some low-SES children maintain good metabolic health across the life span, but the factors responsible for their resilience are not well understood. This study examined the role of threat vigilance as either a moderator or a mediator of the effects of low early life SES on adult metabolic risk. Three hundred twenty-five Canadians aged 15-55 participated (M = 36.4 years, SD = 10.7; 55.4% female). We coded parental occupational status between the ages of 0 and 5 to index early life SES. We used the International Diabetes Federation case definition for MetS based on waist circumference, blood pressure, triglyceride levels, HDL cholesterol, and glycosylated hemoglobin measures. Threat vigilance was assessed using the Weapons Identification Procedure, a visual discrimination paradigm that captures implicit perceptions of threat. Analyses supported the moderator hypothesis: low early life SES was associated with MetS diagnosis exclusively among those with high levels of threat vigilance. This suggests that low early life SES environments that heighten vigilance to threat might be particularly detrimental for metabolic health. Conversely, low threat vigilance may buffer against the metabolic risks associated with socioeconomic disadvantage.

Serum levels of omentin-1 are increased after weight loss and are particularly associated with increases in obese children with metabolic syndrome

AIM

There have been very few paediatric studies on omentin-1, an anti-inflammatory adipokine that provides a link between adiposity, insulin resistance and metabolic syndrome. This Chinese study evaluated the association between omentin-1 and metabolic syndrome and analysed the effect of a six-month lifestyle intervention on the levels in obese children.

METHODS

We recruited 119 obese outpatients (75% boys) aged 7-18 years from the Second Affiliated Hospital of Xi'an Jiaotong University, who underwent a six- month lifestyle intervention. Our controls were 55 matched children with normal weight. Anthropometric parameters, biochemical data and circulating omentin-1 levels were measured at baseline and after six months.

RESULTS

Of the 119 obese children, 32 (27%) had metabolic syndrome. The obese children, particularly those with metabolic syndrome, had significantly lower serum omentin-1 levels at baseline than the controls. We also found that the omentin-1 levels were negatively associated with their body mass index, waist circumference and homoeostasis model assessment of insulin resistance. After the six-month lifestyle intervention, the obese children showed significant weight loss and their omentin-1 levels increased.

CONCLUSION

Serum omentin-1 was regulated by weight and seemed to be associated with children's metabolic disorders. A six-month lifestyle intervention significantly increased serum omentin-1 levels.

Early-Life Socioeconomic Disadvantage and Metabolic Health Disparities

OBJECTIVE

A quarter of the world's population have metabolic syndrome (MetS). MetS prevalence is stratified by socioeconomic status (SES), such that low SES is associated with higher MetS risk. The present study examined the relative roles of early-life SES and current SES in explaining MetS risk.

METHODS

Participants (N = 354; ages = 15-55 years, M [SD] = 36.5 [10.7] years; 55% female; 72.9% white, 16.9% Asian, 10.2% others) were evaluated for SES and MetS. All were in good health, defined as free of chronic medical illness and acute infectious disease. Using occupational status as a proxy for SES, we recruited roughly equal numbers of participants with low-low, low-high, high-low, and high-high combinations of early-life and current SES. We used the International Diabetes Federation definition for MetS using race- and sex-specific cutoffs for waist circumference, triglyceride levels, high-density lipoprotein cholesterol, blood pressure, and glycosylated hemoglobin levels.

RESULTS

Analyses revealed a main effect of low early-life SES on increased MetS risk according to the three separate definitions. They included the traditional MetS diagnosis (odds ratio [OR] = 1.53, confidence interval [CI] = 1.01-2.33, p = .044), the number of MetS components for which diagnostic thresholds were met (OR = 1.61, CI = 1.10-2.38, p = .015), and a continuous indicator of metabolic risk based on factor analysis (F(1,350) = 6.71, p = .010, partial η = .019). There was also a significant interaction of early-life SES and current SES in predicting MetS diagnosis (OR = 1.54, CI = 1.02-2.34). The main effects of current SES were nonsignificant in all analyses.

CONCLUSIONS

These findings suggest that MetS health disparities originate in childhood, which may be an opportune period for interventions.

Active and strong: physical activity, muscular strength, and metabolic risk in children

OBJECTIVES

This study explored the associations among physical activity, muscular strength, and metabolic risk among children.

METHODS

The sample included 378 Portuguese children (213 girls; 9-11 years). Moderate-to-vigorous physical activity was assessed by accelerometry and children were classified as active (≥60 min/day) or insufficiently active (<60 min/day). Static strength was expressed as the ratio of handgrip strength/body weight and used to classify children as having high (≥P50) or low (<P50) muscular strength. Children were classified into four groups: active and high strength, active and low strength, insufficiently active and high strength, insufficiently active and low strength. A continuous metabolic risk score was computed from cardiometabolic risk factors.

RESULTS

In general, the insufficiently active and low strength group had the worst metabolic risk score, and the active and high strength group had the best. Significant differences were found within physical activity groups for metabolic risk: children classified as "active and high strength" and "insufficiently active and high strength" had better metabolic risk scores than "active and low strength" and "insufficiently active and low strength", respectively.

CONCLUSIONS

Muscular strength has a relevant role in attenuating the association between physical inactivity and metabolic risk in children; a further benefit was identified in children with high physical activity and high muscular strength.

Review: Obesity and cardiometabolic syndrome in children

The cardiometabolic syndrome is highly prevalent among overweight youth. The risk of developing the cardiometabolic syndrome is likely triggered or exacerbated by concurrent obesity, unhealthy lifestyle/eating habits, and hormonal changes (puberty). Current screening recommendations include measurement of blood pressure, fasting insulin and glucose, and total cholesterol. However, limiting assessments to these measures underestimates cardiometabolic risk in overweight youth, particularly minorities. Early identification of cardiometabolic risk in its incipient stages may justify early and more aggressive intervention to prevent progression and complications. This review provides rationale for additional assessments to determine cardiometabolic risk in overweight youth and recommends treatment options.

Reproducibility and Relative Validity of a Short Food Frequency Questionnaire in 9-10 Year-Old Children

The aim of this study was to assess the reproducibility and validity of a non-quantitative 28-item food frequency questionnaire (FFQ). Children aged 9-10 years (n = 50) from three schools in Dunedin, New Zealand, completed the FFQ twice and a four-day estimated food diary (4DEFD) over a two-week period. Intraclass correlation coefficients (ICC) and Spearman's correlation coefficients (SCC) were used to determine reproducibility and validity of the FFQ, respectively. Weekly intakes were estimated for each food item and aggregated into 23 food items/groups. More than half of the food items/groups (52.2%) had an ICC ≥0.5. The median SCC between FFQ administrations was 0.66 (ranging from 0.40 for processed meat to 0.82 for sweets and non-dairy drinks). Cross-classification analysis between the first FFQ and 4DEFD for ranking participants into thirds showed that breakfast cereals had the highest agreement (54.0%) and pasta the lowest (34.0%). In validity analyses, 70% of food items/groups had a SCC ≥0.3. Results indicate that the FFQ is a useful tool for ranking children according to food items/groups intake. The low respondent burden and relative simplicity of the FFQ makes it suitable for use in large cohort studies of 9-10 year-old children in New Zealand.

Influence of physical fitness on cardio-metabolic risk factors in European children. The IDEFICS study

OBJECTIVE

The aim of the study was to assess the associations of individual and combined physical fitness components with single and clustering of cardio-metabolic risk factors in children.

SUBJECTS/METHODS

This 2-year longitudinal study included a total of 1635 European children aged 6-11 years. The test battery included cardio-respiratory fitness (20-m shuttle run test), upper-limb strength (handgrip test), lower-limb strength (standing long jump test), balance (flamingo test), flexibility (back-saver sit-and-reach) and speed (40-m sprint test). Metabolic risk was assessed through z-score standardization using four components: waist circumference, blood pressure (systolic and diastolic), blood lipids (triglycerides and high-density lipoprotein) and insulin resistance (homeostasis model assessment). Mixed model regression analyses were adjusted for sex, age, parental education, sugar and fat intake, and body mass index.

RESULTS

Physical fitness was inversely associated with clustered metabolic risk (P<0.001). All coefficients showed a higher clustered metabolic risk with lower physical fitness, except for upper-limb strength (β=0.057; P=0.002) where the opposite association was found. Cardio-respiratory fitness (β=-0.124; P<0.001) and lower-limb strength (β=-0.076; P=0.002) were the most important longitudinal determinants. The effects of cardio-respiratory fitness were even independent of the amount of vigorous-to-moderate activity (β=-0.059; P=0.029). Among all the metabolic risk components, blood pressure seemed not well predicted by physical fitness, while waist circumference, blood lipids and insulin resistance all seemed significantly predicted by physical fitness.

CONCLUSION

Poor physical fitness in children is associated with the development of cardio-metabolic risk factors. Based on our results, this risk might be modified by improving mainly cardio-respiratory fitness and lower-limb muscular strength.

Cognitive control in preadolescent children with risk factors for metabolic syndrome

OBJECTIVE

To investigate the relationship between cognitive control and metabolic syndrome (MetS) risk factors in preadolescent children while controlling for aerobic fitness and weight status.

METHODS

Hierarchical regression analyses were conducted using aerobic fitness, demographic, and MetS risk-factor variables in a sample of 2nd- and 3rd-grade children (n = 139) who performed a modified version of a flanker task to assess cognitive control. Flanker performance was also compared between children that met no MetS risk-factor criteria (n = 70), and children who met 1 criterion or more (n = 69).

RESULTS

Regression analyses indicated that after controlling for demographic variables and fitness, HDL cholesterol exhibited an independent negative association with flanker reaction time (RT). Group comparisons further revealed that children with no risk factors demonstrated overall shorter RT than the at-risk group. In addition, at-risk children exhibited larger accuracy-interference scores (i.e., poorer performance) for the more difficult conditions of the flanker task that required the up-regulation of cognitive control to meet elevated task demands.

CONCLUSIONS

These findings are consonant with the previous literature reporting a beneficial influence of aerobic fitness on cognitive control, and reveal new evidence that children without risk factors for MetS exhibit better inhibitory control and increased cognitive flexibility than do at-risk children. In addition to aerobic fitness, these risk factors may serve as important biomarkers for understanding the potential cognitive implications of MetS risk in younger generations.

Independent association of clustered metabolic risk factors with cardiorespiratory fitness in youth aged 11-17 years

BACKGROUND

Although the prevalence of metabolic syndrome (MetS) has increased in youth, the potential independent contribution of cardiorespiratory fitness (CRF) to the clustering of metabolic risk factors has received relatively little attention.

AIM

This study evaluated associations between the clustering of metabolic risk factors and CRF in a sample of youth.

SUBJECTS AND METHODS

Height, weight, BMI, fasting glucose, insulin, HDL-cholesterol, triglycerides and blood pressures were measured in a cross-sectional sample of 924 youth (402 males, 522 females) of 11-17 years. CRF was assessed using the 20-metre shuttle run test. Physical activity (PA) was measured with a 3-day diary. Outcome variables were statistically normalized and expressed as Z-scores. A MetS risk score was computed as the mean of the Z-scores. Multiple linear regression was used to test associations between CRF and metabolic risk, adjusted for age, sex, BMI, PA and parental education.

RESULTS

CRF was inversely associated with MetS after adjustment for potential confounders. After adjusting for BMI, the relationship between CRF and metabolic risk has substantially improved.

CONCLUSION

CRF was independently associated with the clustering of metabolic risk factors in youth of 11-17 years of age.

Associations between macronutrient intake and serum lipid profile depend on body fat in European adolescents: the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study

The present study aimed to investigate the relationships between macronutrient intake and serum lipid profile in adolescents from eight European cities participating in the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) cross-sectional study (2006-7), and to assess the role of body fat-related variables in these associations. Weight, height, waist circumference, skinfold thicknesses, total cholesterol, HDL-cholesterol (HDL-C), LDL-cholesterol, TAG, apoB and apoA1 were measured in 454 adolescents (44% boys) aged 12.5-17.5 years. Macronutrient intake (g/4180 kJ per d (1000 kcal per d)) was assessed using two non-consecutive 24 h dietary recalls. Associations were evaluated by multi-level analysis and adjusted for sex, age, maternal education, centre, sum of four skinfolds, moderate-to-vigorous physical activity, sedentary behaviours and diet quality index for adolescents. Carbohydrate intake was inversely associated with HDL-C (β = - 0.189, P< 0.001). An inverse association was found between fat intake and TAG (β = - 0.319, P< 0.001). Associations between macronutrient intake and serum lipids varied according to adiposity levels, i.e. an inverse association between carbohydrate intake and HDL-C was only observed in those adolescents with a higher waist:height ratio. As serum lipids and excess body fat are the major markers of CVD, these findings should be considered when developing strategies to prevent the risk of CVD among adolescents.

Is dairy consumption associated with low cardiovascular disease risk in European adolescents? Results from the HELENA Study

OBJECTIVE

To identify those food groups best discriminating individuals at high/low cardiovascular disease (CVD) risk and to investigate the relationship between dairy consumption and CVD risk factors (individual and scores) in adolescents (12.5-17.5 years) from eight European cities participating in the cross-sectional (2006-2007) HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) project.

METHODS

Diet, waist circumference, skin-folds thickness, systolic blood pressure, insulin resistance, triglycerides, total cholesterol/high-density lipoprotein ratio and cardiorespiratory fitness (CRF) were assessed in 511 (49.9% boys) adolescents. Individual z-scores of CVD risk factors were summed to compute sex-specific clustered CVD risk scores.

RESULTS

Dairy emerged as the food group best discriminating adolescents at low/high CVD risk. In both genders, waist circumference and sum of skin-folds were inversely associated with consumption of milk and yogurt, and milk- and yogurt-based beverages, whereas a positive association was observed with CRF. Moreover, CVD risk score (β = -0.230, P = 0.001) was also inversely associated with overall dairy consumption only in girls.

DISCUSSION

Dairy consumption is associated with lower adiposity and higher CRF in these adolescents. An inverse association between CVD risk score and dairy consumption is also depicted in girls. The study adds further evidence to the scarce literature on the influence of milk and dairy products on adolescents' cardiovascular health.

Predictors of food and physical activity patterns among schoolchildren in the region of Sousse, Tunisia

AIM

To facilitate the improvement of future interventions, it's important to know the determinants of healthy behaviors. Our aim was to determine the predictors of healthy habits in a school based intervention study to promote healthy diet and physical activity among schoolchildren in the region of Sousse, Tunisia.

METHODS

It was a quasi-experimental intervention study with two groups: control and intervention group with pre-post evaluation of nutrition and physical activity intention and behavior in each group. The target population was composed with students aged 12-16 years schooled in colleges of Sousse in Tunisia. To evaluate the intervention, a sampling was used to include 2200 students who participated to the questionnaire. All the students of intervention group received a standardized program with information about healthy nutrition and physical activity. An Arabic pre-tested and auto-administered questionnaire was used to assess nutrition and physical activity intention and behavior before and after the intervention.

RESULTS

The intervention group's posttest knowledge and behavioral intention were significantly higher than the control group's posttest. No significant differences occurred in posttest attitudes between the control and intervention groups. A multivariate logistic regression models were used to identify the predictors of students' "healthy behavior".

CONCLUSION

This school based intervention improved eating and physical activity intentions and behaviors among schoolchildren. "Healthy behaviors' were determined by age, father's profession and home characteristics. This finding could direct future interventions to disadvantaged categories.

The role of dietary fat on the association between dietary amino acids and serum lipid profile in European adolescents participating in the HELENA Study

BACKGROUND/OBJECTIVES

The objective of this study was to examine the relationship between amino acid (AA) intake and serum lipid profile in European adolescents from eight European cities participating in the cross-sectional (2006-2007) HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study, and to assess whether this association was independent of total fat intake.

SUBJECTS/METHODS

Diet, skinfold thickness, triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), TC/HDL-c ratio, low-density lipoprotein cholesterol (LDL-c), apolipoprotein B (Apo B), apolipoprotein A1 (Apo A1) and Apo B/Apo A1 ratio were measured in 454 12.5- to 17.5-year-old adolescents (44% boys). Intake was assessed via two non-consecutive 24-h dietary recalls. Data on maternal education and sedentary behaviors were obtained via questionnaires. Physical activity was objectively measured by accelerometry.

RESULTS

Alanine, arginine, asparaginic acid, glycine, histidine, lysine and serine intakes were inversely associated with serum TG concentrations in both boys and girls. Intake of other AA like alanine and/or arginine was also inversely associated with serum TC, LDL-c and Apo B/Apo A1 ratio only in girls. An inverse association was observed between intakes of alanine, isoleucine, leucine, methionine, serine, tryptophan, tyrosine and valine and TC/HDL-c ratio among female adolescents. Similar results were found in males for serine and tryptophan intakes. It is noteworthy, however, that associations were no longer significant in both genders when total fat intake was considered as a confounding factor.

CONCLUSIONS

In this sample of adolescents, the association between AA intakes and serum lipid profile did not persist when dietary fat was considered. Therefore, dietary interventions and health promotion activities should focus on fat intake to improve lipid profile and potentially prevent cardiovascular disease.

Relative validity of the Children's Eating Habits Questionnaire-food frequency section among young European children: the IDEFICS Study

OBJECTIVE

To compare, specifically by age group, proxy-reported food group estimates obtained from the food frequency section of the Children's Eating Habits questionnaire (CEHQ-FFQ) against the estimates of two non-consecutive 24 h dietary recalls (24-HDR).

DESIGN

Estimates of food group intakes assessed via the forty-three-food-group CEHQ-FFQ were compared with those obtained by a computerized 24-HDR. Agreement on frequencies of intakes (equal to the number of portions per recall period) between the two instruments was examined using crude and de-attenuated Pearson's correlation coefficients, cross-classification analyses, weighted kappa statistics (κ w) and Bland-Altman analysis.

SETTING

Kindergartens/schools from eight European countries participating in the IDEFICS (Identification and prevention of Dietary- and lifestyle-induced health EFfects In Children and infantS) Study cross-sectional survey (2007-2008).

SUBJECTS

Children aged 2-9 years (n 2508, 50·4% boys).

RESULTS

The CEHQ-FFQ provided higher intake estimates for most of the food groups than the 24-HDR. De-attenuated Pearson correlation coefficients ranged from 0·01 (sweetened fruit) to 0·48 (sweetened milk) in children aged 2-<6 years (mean = 0·25) and from 0·01 (milled cereal) to 0·44 (water) in children aged 6-9 years (mean = 0·23). An average of 32% and 31% of food group intakes were assigned to the same quartile in younger and older children, respectively, and classification into extreme opposite quartiles was ≤12% for all food groups in both age groups. Mean κ w was 0·20 for 2-<6-year-olds and 0·17 for 6-9-year-olds.

CONCLUSIONS

The strength of association estimates assessed by the CEHQ-FFQ and the 24-HDR varied by food group and by age group. Observed level of agreement and CEHQ-FFQ ability to rank children according to intakes of food groups were considered to be low.

Gender specific effect of major dietary patterns on the metabolic syndrome risk in Korean pre-pubertal children

There is a lack of data on metabolic risk factors during pre-puberty, which is important for identifying the subgroups of youth, at whom early interventions should be targeted. In this study, we evaluated the prevalence of metabolic risk factors and its subsequent relations with dietary patterns in Korean pre-pubertal children through a cross-sectional sample (n = 1,008; boys = 513) of pre-pubertal children (aged 8-9 years) from a sub-study of the Korea Metabolic Syndrome Research Initiatives (KMSRI) in Seoul, Korea. Measures of anthropometry and blood pressure as well as fasting blood samples were used in the analysis. A three-day food records were collected. The metabolic syndrome was defined according to the age-adjusted National Cholesterol Education Program Adult Treatment Panel III guidelines. An added metabolic risk score was calculated for each subject by summing the quintile values of the five individual risk factors. Among the 5 risk components of metabolic syndrome, high waist circumference (WC) was the major factor (P < 0.001). A significant increasing trend of the added metabolic syndrome risk score was observed with the increase of WC (P (trend) < 0.001) among both genders. The cutoff point for high WC for pre-pubertal children was 61.3 cm for boys and 59.9 cm for girls. The prevalence of high triglyceride (TG) values was significantly higher in girls than it was in boys (P < 0.01). Girls in the highest quintile of balanced dietary pattern scores had lower TG values (P (trend) = 0.032) than did those in the lowest quintile. Moreover, girls in the highest quintile of western dietary pattern scores showed increasing trend for the added metabolic risk score (P (trend) = 0.026) compared with those in the lowest quintile. Adverse associations exist between western dietary patterns and the accumulation of metabolic risks among girls, not in boys, even during pre-puberty.

Prevalence of overweight and obesity in children and adolescents aged 2-16 years

OBJECTIVES

To estimate the prevalence of obesity and overweight in children and adolescents in our city and to investigate the associated factors.

SUBJECTS AND METHODS

A cross-sectional study of 1317 children and adolescents aged 2-16 years. Multistage probability sampling was used to select three groups of subjects: 411 aged 12 to 16 years, 504 aged 6 to 12 years, and 402 aged 2 to 6 years. Body mass index was calculated, and obesity and overweight were diagnosed using the threshold levels of the International Obesity Task Force for children and adolescents. Parents were asked about eating habits, health, social, and demographic aspects. Results are given as percentages (95% confidence interval). The relationship between obesity and overweight and the different variables was studied using multiple logistic regression. The adjusted odds ratio (OR) was calculated.

RESULTS

Among children and adolescents aged 2-16 years, 9.5% (8.0%-11.0%) were obese and 22.4% (23.3%-24.6%) were overweight. Of subjects aged 12-16 years, 8.5% (5.9%-11.2%) were obese and 20.5% (16.7%-24.3%) were overweight. In the groups aged 6-12 years and 2-6 years, rates of obesity and overweight were 11.6% (8.9% -14.3%) and 31.0% (27.0-35.0) and 8.0% (5.4%-10.6%) and 13.6% (10.3%-16.9%) respectively. Obesity or overweight was associated to age (OR 1.21; P<0.001), maternal obesity (OR 10.99; P= 0.008), a birthweight higher than 4kg (OR 2.91; p 0.002), and formula feeding (OR 1.82; P= 0.005).

CONCLUSION

Obesity and overweight in children and adolescents are highly prevalent problems in our city.

VNN1 gene expression levels and the G-137T polymorphism are associated with HDL-C levels in Mexican prepubertal children

BACKGROUND

VNN1 gene expression levels and the G-137T polymorphism have been associated with high density lipoprotein cholesterol (HDL-C) levels in Mexican American adults. We aim to evaluate the contribution of VNN1 gene expression and the G-137T variant to HDL-C levels and other metabolic traits in Mexican prepubertal children.

METHODOLOGY/PRINCIPAL FINDINGS

VNN1 mRNA expression levels were quantified in peripheral blood leukocytes from 224 unrelated Mexican-Mestizo children aged 6-8 years (107 boys and 117 girls) and were genotyped for the G-137T variant (rs4897612). To account for population stratification, a panel of 10 ancestry informative markers was analyzed. After adjustment for admixture, the TT genotype was significantly associated with lower VNN1 mRNA expression levels (P = 2.9 × 10(-5)), decreased HDL-C levels (β = -6.19, P = 0.028) and with higher body mass index (BMI) z-score (β = 0.48, P = 0.024) in the total sample. In addition, VNN1 expression showed a positive correlation with HDL-C levels (r = 0.220; P = 0.017) and a negative correlation with BMI z-score (r = -0.225; P = 0.015) only in girls.

CONCLUSION/SIGNIFICANCE

Our data suggest that VNN1 gene expression and the G-137T variant are associated with HDL-C levels in Mexican children, particularly in prepubertal girls.

Physical activity, fitness and the metabolic syndrome in rural youths from Mozambique

BACKGROUND

Except for North America and Europe, few studies have reported the association among physical activity (PA), cardiorespiratory fitness (CRF) and metabolic syndrome (MetS) in youths, especially for rural African youth.

AIM

The aims of this study were to determine the prevalence of PA levels, CRF, MetS and its indicators, and examine the association between these variables in a school-aged sample of youth from rural Mozambique.

SUBJECTS AND METHODS

The sample included 209 children and adolescents aged 7-15 years old from Calanga, a rural community in Mozambique. PA was estimated with a culturally-specific questionnaire. CRF was determined by 1-mile run test. Indicators of the MetS included fasting glucose, triglycerides, total cholesterol, blood pressure and body mass index. A continuous metabolic risk score was computed.

RESULTS

Results showed high levels of PA and CRF and a low prevalence of MetS ( < 2%) among children and adolescents from Calanga. However, there was a moderately high prevalence of elevated blood pressure (81.8%) and triglycerides (18.7%), respectively. There were no significant associations between PA, CRF and MetS.

CONCLUSION

Youths from Calanga are physically active and possess high CRF and their lifestyle may be a protective effect against MetS.

Comparisons between inverted body mass index and body mass index as proxies for body fatness and risk factors for metabolic risk and cardiorespiratory fitness in Portuguese adolescents

OBJECTIVES

To compare inverted body mass index (iBMI, cm(2) /kg) and body mass index (BMI, kg/m(2) ) as predictors of body fatness, metabolic risk, and cardiovascular fitness in adolescents.

METHODS

A cross-sectional school-based study was conducted on 445 Portuguese adolescents (252 girls and 193 boys) aged 10-17 years. Height and body mass were assessed to determine iBMI and BMI, percent body fatness was determined from skinfold measures (tricep, subscapular) using the Slaughter et al. (1988: Hum Biol 60: 709-723) regression equation and cardiorespiratory fitness (CRF) was assessed using the 20-m shuttle run test. Capillary blood sampling was used to determine: Total cholesterol, triglycerides, high, and low density lipoprotein. These were combined with measures of systolic blood pressure and waist circumference as z-scores. Metabolic risk (MRS) was constructed by summing the z-scores.

RESULTS

iBMI and BMI were both significantly related to percent body fatness, CRF and MRS (all P = 0.005 or better). BMI was not normally distributed (P = 0.0001), whereas iBMI was (P > 0.05). Regression analysis identified that iBMI and BMI, both alongside for age, were significant predictors of percent body fatness, CRF and MRS (all P = 0.005 or better). Compared with BMI, iBMI was a similar predictor of CRF, MRS and body fatness.

CONCLUSIONS

iBMI offers a biologically sound alternative to BMI to assess the effect of weight status on MRS and CRF in adolescents and allows appropriate use of parametrical statistical techniques without changing the conclusions drawn from such data.

Metabolic syndrome in a sample of the 6- to 16-year-old overweight or obese pediatric population: a comparison of two definitions

Purpose

The purpose of this study was to estimate the presence of metabolic syndrome (MS) in a group of children and adolescents with a body mass index (BMI) above the 85th percentile for their age and sex in Qazvin Province, Iran; to evaluate the relationship between obesity and metabolic abnormalities; and to compare two proposed definitions of MS.

Patients and methods

The study was conducted on 100 healthy subjects aged between 6 and 16 years (average age, 10.52 ± 2.51 years) with a high BMI for their age and sex. Fifty- eight percent of subjects were female. Physical examination including evaluation of weight, height, BMI, and blood pressure measurement was performed (“overweight” was defined as a BMI between the 85th and 95th percentiles for children of the same age and sex; “obese” was defined as a BMI over the 95th percentile for children of the same age and sex). Blood levels of glucose, insulin, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, and uric acid were measured after a 12-hour overnight fast. The authors used and compared two definitions of MS: the National Cholesterol Education Program’s Adult Treatment Panel III (NCEP ATP III) criteria and a modified definition by Weiss et al. Variables were compared using the Student’s t-test and chi-square and Mann-Whitney U tests, and agreement between the two definitions was analyzed using kappa values.

Results

The subjects had a mean BMI of 26.02 ± 4.38 and 80% had obesity. Insulin resistance was found in 81% of the study population. MS was present in ten (50%) of the overweight and 53 (66.2%) of the obese subjects using the NCEP ATP III criteria. MS was present in five (25%) of the overweight and 34 (42.5%) of the obese subjects using the definition by Weiss et al. The overall kappa value for the two definitions of MS was 0.533. There were no statistically significant differences between the two definitions of MS in participants.

Conclusion

The prevalence of MS in children and adolescents depends on the criteria chosen and their respective cutoff points. The NCEP ATP III criteria, the parameters of which include higher cutoff values for high-density lipoprotein cholesterol and triglycerides, detected the higher prevalence and therefore the NCEP ATP III criteria are able to diagnose a larger number of children and adolescents at metabolic risk.

Muscular and cardiorespiratory fitness are independently associated with metabolic risk in adolescents: the HELENA study

OBJECTIVE

To examine the independent associations of muscular and cardiorespiratory fitness with clustered metabolic risk in adolescents.

METHODS

Participants were 709 adolescents (346 boys) from 10 European centers, aged 12.5-17.5 yr, evaluated as a part of the Healthy Lifestyle in Europe by Nutrition in Adolescents cross-sectional study (HELENA-CSS). A muscular fitness score was computed using handgrip strength and standing long jump. Cardiorespiratory fitness was measured using the 20-m shuttle run test. Age- and gender-specific z-scores of waist circumference, systolic blood pressure, triglycerides, ratio total cholesterol/high-density lipoprotein cholesterol, and insulin resistance (homeostasis model assessment) were summed to create a metabolic risk score.

RESULTS

Muscular fitness was negatively associated with clustered metabolic risk independent of cardiorespiratory fitness (β = -0.249, p < 0.001). Independent of muscular fitness, an inverse association was also found between cardiorespiratory fitness and clustered metabolic risk (β = 0.264, p < 0.001). The odds ratios for having a high clustered risk (above or equal 1 standard deviation) were 5.3 [95% confidence interval (CI) = 2.6-10.6] and 4.3 (95% CI = 2.0-9.3) in the least fit quartile compared with the most fit quartile for muscular and cardiorespiratory fitness, respectively. Significant differences in metabolic risk between muscular fitness levels persisted among non-overweight (p = 0.012) and overweight participants (p = 0.011).

CONCLUSION

Muscular and cardiorespiratory fitness are independently associated with metabolic risk in adolescents. These results support current physical activity recommendations for youth, which include muscle strengthening activities in addition to aerobic exercise.

Significant associations among hemostatic parameters, adipokines, and components of the metabolic syndrome in Japanese preschool children

Development of cardiovascular diseases could originate in early childhood. However, reference values of hemostatic parameters and adipokines in preschool children remain to be explored. We measured blood levels of adipokines and parameters of the hemostatic/fibrinolytic systems in 167 healthy children aged 4 to 6 years at 9:00 to 10:30 am after a strictly enforced overnight fast. Participants with body mass index (BMI) values ≥90th percentile had significantly higher values of systolic blood pressure and heart rate, as well as blood levels of insulin, coagulation factor (F) VII, FX, protein S, leptin, and homeostasis model assessment of insulin resistance (HOMA-IR), and lower values of desacyl-ghrelin than children with BMI < 90th percentile. Circulating levels of fibrinogen and leptin increased with increased number of cardiovascular risk factors. Stepwise regression analysis identified many hematological variables to be associated with features of the metabolic syndrome. The results implicated the hemostatic/fibrinolytic system or adipokines in the insidious progression of cardiovascular diseases from an early age.

Effects on metabolic health after a 1-year-lifestyle intervention in overweight and obese children: a randomized controlled trial

Objective. To evaluate the effect of a family-based intervention on anthropometric and metabolic markers in overweight and obese children. Methods. Overweight or obese 8-12 years olds (n = 93) were randomized into intervention or control groups. The intervention group participated in a program aiming for lifestyle changes regarding food habits and physical activity. Anthropometric measures and venous blood samples were collected from all children at baseline and after 1 year. Results. BMI z-scores decreased in both groups, 0.22 (P = 0.002) and 0.23 (P = 0.003) in intervention and control group, respectively, during the 1-year study, but there was no difference in BMI between the groups at 1-year measurement (P = 0.338). After 1 year, there was a significant difference in waist circumference, waist/hip ratio, and apolipoprotein B/A1 ratio between intervention and control group. Conclusions. The intervention had limited effects on anthropometrics and metabolic markers, which emphasizes the need of preventing childhood overweight and obesity.

The metabolic syndrome and body composition in childhood cancer survivors

Purpose

Long-term survivors of childhood cancer appear to have an increased risk for the metabolic syndrome, subsequent type 2 diabetes and cardiovascular disease in adulthood compared to healthy children. The purpose of this study was to investigate the frequency of the metabolic syndrome and associated factors in childhood cancer survivors at a single center in Korea.

Methods

We performed a retrospective review of medical records of 98 childhood cancer survivors who were diagnosed and completed anticancer treatment at Samsung Medical Center, Seoul, Korea between Jan. 1996 and Dec. 2007. Parameters of metabolic syndrome were evaluated between Jan. 2008 and Dec. 2009. Clinical and biochemical findings including body fat percentage were analyzed.

Results

A total of 19 (19.4%) patients had the metabolic syndrome. The median body fat percentage was 31.5%. The body mass index and waist circumference were positively correlated with the cranial irradiation dose (r=0.38, P<0.001 and r=0.44, P<0.00, respectively). Sixty-one (62.2%) patients had at least one abnormal lipid value. The triglyceride showed significant positive correlation with the body fat percentage (r=0.26, P=0.03). The high density lipoprotein cholesterol showed significant negative correlation with the percent body fat (r=-0.26, P=0.03).

Conclusion

Childhood cancer survivors should have thorough metabolic evaluation including measurement of body fat percentage even if they are not obese. A better understanding of the determinants of the metabolic syndrome during adolescence might provide preventive interventions for improving health outcomes in adulthood.

[Obesity-related metabolic disorders in childhood and adolescence]

Obesity is the most frequent nutritional disorder in childhood and adolescence. The rise in its prevalence and severity has underlined the numerous and significant obesity-related metabolic disorders. Altered glucose metabolism, manifested as impaired glucose tolerance, appears early in severely obese children and adolescents. Obese young people with glucose intolerance are characterized by marked peripheral insulin resistance and relative beta-cell failure. Lipid deposition in muscle and the visceral compartment, and not only obesity per se, is related to increased peripheral insulin resistance, the triggering factor of the metabolic syndrome. Other elements of the metabolic syndrome, such as dyslipidaemia, and hypertension, are already present in obese youngsters and worsen with the degree of obesity. The long-term impact of obesity-related insulin resistance on cardiovascular morbidity in these patients is expected to emerge as these youngsters become young adults.

Metabolic syndrome, adipokines and ghrelin in overweight and obese schoolchildren: results of a 1-year lifestyle intervention programme

The aim of this study was to evaluate the effect of a lifestyle intervention programme (nutrition and exercise counselling) on metabolic syndrome (MS) components, adipokines (leptin, adiponectin) and ghrelin levels in overweight children. A total of 61 overweight children aged 7-9 years (≥ 85th body mass index (BMI) percentile; 27 boys/34 girls) were randomly assigned and completed a 1-year individual (IT) or group-based treatment (GT). Anthropometric and biochemical parameters were assessed at baseline, at 6 months and at 1 year. Twenty-two normal weight children (<85th BMI percentile; 7-9 years old; 13 boys/nine girls) were also evaluated at baseline. Insulin resistance (IR) was determined by the homeostasis model assessment of IR (HOMA-IR). Overweight children presented significantly higher blood pressure, triglycerides, apolipoprotein B, insulin, HOMA-IR, leptin, C-reactive protein and homocysteine levels, while apolipoprotein A-I was significantly lower. At baseline, MS was present in ten overweight children, of which only five maintained it at 1 year. Leptin and ghrelin levels were associated with IR and MS components. MS was predicted by apolipoprotein A-I, insulin and pre-puberty. The lifestyle intervention led to a significant improvement in standard deviation score of BMI, waist circumference/height ratio and lipid profile. Changes in insulin, HOMA-IR, leptin and adiponectin were not significant. Ghrelin behaved differently between IT and GT. The GT intervention seems to be more successful, with a decrease in BMI Z-score and an improvement of metabolic parameters. In conclusion, overweight children have multiple risk factors associated with MS. A lifestyle intervention programme seems to be an effective mean for reducing obesity and MS components and improving adipokines concentrations.

Ability of different measures of adiposity to identify high metabolic risk in adolescents

Introduction. This study aimed to evaluate the screening performance of different measures of adiposity: body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR) for high metabolic risk in a sample of adolescents. Methods. A cross-sectional school-based study was conducted on 517 adolescents aged 15-18, from the Azorean Islands, Portugal. We measured fasting glucose, insulin, total cholesterol (TC), HDL-cholesterol, triglycerides, and systolic blood pressure. HOMA and TC/HDL-C ratio were calculated. For each of these variables, a Z-score was computed by age and sex. A metabolic risk score (MRS) was constructed by summing the Z-scores of all individual risk factors. High risk was considered when the individual had ≥1SD of this score. Receiver-operating characteristics (ROC) were used. Results. Linear regression analyses showed that, after adjusting for age and pubertal stage, all different measures of adiposity are positively and significantly associated with MRS in both sexes, with exception of WHtR for boys. BMI, WC, and WHtR performed well in detecting high MRS, indicated by areas under the curve (AUC), with slightly greater AUC for BMI than for WC and WHtR in both sexes. Conclusion. All measures of adiposity were significantly associated with metabolic risk factors in a sample of Portuguese adolescents.

Prevalence and association between obesity and metabolic syndrome among Chinese elementary school children: a school-based survey

Background

China has experienced an increase in the prevalence of childhood overweight/obesity over the last decades. The purpose of this study was to examine the prevalence of obesity and metabolic syndrome among Chinese school children and determine if there is a significant association between childhood obesity and metabolic syndrome.

Methods

A cross-sectional study was conducted among 1844 children (938 males and 906 females) in six elementary schools at Guangzhou city from April to June 2009. The body mass index (BMI), waist circumference, blood pressure, Tanner stage, lipids, insulin and glucose levels were determined. Criteria analogous to ATPIII were used for diagnosis of metabolic syndrome in children.

Results

Among 1844 children aged 7-14 years, 205 (11.1%) were overweight, and 133 (7.2%) were obese. The prevalence of metabolic syndrome was 6.6% overall, 33.1% in obese, 20.5% in overweight and 2.3% in normal weight children. Multiple logistic regression analysis showed that BMI (3rd quartile)(OR 3.28; 95%CI 0.35-30.56), BMI (4th quartile)(OR 17.98; 95%CI 1.75-184.34), homeostasis model assessment (HOMA-IR) (2nd quartile) (OR2.36; 95% CI 0.46-12.09), HOMA-IR (3rd quartile) (OR 2.46; 95% CI 0.48-12.66), HOMA-IR (4th quartile) (OR3.87; 95% CI 0.72-20.71) were significantly associated with metabolic syndrome.

Conclusions

The current epidemic of obesity with subsequent increasing cardiovascular risk factors has constituted a threat to the health of school children in China. HOMA-IR and BMI were strong predictors of metabolic syndrome in children. Therefore, rigorous obesity prevention programs should be implemented among them.

Differences in male and female adolescents from various racial groups in the relationship between insulin resistance-associated parameters with sugar-sweetened beverage intake and physical activity levels

OBJECTIVE

To describe racial and gender differences in insulin resistance-associated parameters due to sugar-sweetened beverage (SSB) intake and physical activity (PA) levels in the adolescent population.

METHODS

Data from individuals aged 12 to 19 years from the National Health and Nutrition Examination Survey during the years 1999-2004 were analyzed. SSB intake and PA levels were evaluated in Non-Hispanic whites, Non-Hispanic blacks, and Mexican Americans. Outcome measures included measurements of insulin sensitivity, lipids, blood pressure, waist circumference, and body mass index.

RESULTS

Multivariate linear regression analyses showed that anthropometric measurements, metabolic parameters, and indices of insulin resistance differed among the racial groups. Moreover, within each of these racial groups, they differed between the sexes.

CONCLUSIONS

The differing relationships between insulin resistance-associated parameters and SSB intake and PA levels among racial groups and between the sexes illustrate the importance of race and gender in the investigation of diseases such as obesity and metabolic syndrome.

Markers of metabolic syndrome in obese children before and after 1-year lifestyle intervention program

PURPOSE

Excess weight may be related to the development of adverse cardiometabolic risk factors in children. The aim of this study was to evaluate the effect of a lifestyle intervention program (nutrition and exercise counseling) on anthropometric parameters and metabolic syndrome (MS) components in Portuguese overweight/obese children.

METHODS

A total of 83 overweight/obese children aged 7-9 years were assigned to a 1-year individual or group-based treatment (GT); 61 children (z-score BMI (zBMI): 1.93 ± 0.28; 27 boys and 34 girls) completed the program. Anthropometric and biochemical parameters were assessed at baseline, at 6 months and at 1 year.

RESULTS

The overweight/obese children, compared to normal-weight ones, presented significantly higher blood pressure, total-cholesterol, total-cholesterol/high density lipoprotein cholesterol (HDL) ratio, triglycerides, Apolipoprotein B and C-reactive protein levels, while HDL and Apolipoprotein A-I were significantly lower. At baseline, the prevalence of MS was 16.4% in overweight/obese and 0% in normal-weight children. The number of components of MS was significantly higher in children with higher zBMI. Lifestyle intervention led to a significant improvement in zBMI, waist circumference/height ratio, HDL, triglycerides, Apolipoprotein A-I, and Apolipoprotein B levels. The prevalence of MS decreased to 14.8%. The GT intervention seems to be more successful, with a significant decrease in zBMI and an increase in HDL and a lower drop-out rate.

CONCLUSIONS

Overweight/obese children have multiple risk factors associated with the MS. Lifestyle intervention, both individual and group-based treatment, led to an improvement in the degree of overweight/obesity and in MS components.

Insight into physical activity in combating the infantile metabolic syndrome

Metabolic syndrome (MetS) is increasingly reported in children, mainly in the presence of overweight/obesity. From the most recent report, up to 60% of overweight and obese children can be affected by this syndrome. MetS acquired during childhood has been shown to track into adulthood, including its clinical complications, such as type 2 diabetes and cardiovascular diseases. Among the practical preventive and therapeutic measures to be taken in children, physical activity (PA) appears to be at least as efficient as the most adequate pharmacology. The current literature suggests that exercise programs based either on aerobic-or resistance-type exercises, or a combination of these 2 types of structured activity, may promote insulin sensitivity and weaken or suppress MetS in children. Furthermore, daily-living activities such as brisk walking were found to substantially reduce the risk of MetS among children. Regardless of their weight status, PA needs to be promoted among children as early as possible.

Low muscle fitness is associated with metabolic risk in youth

PURPOSE

To examine the independent associations of muscle fitness and cardiorespiratory fitness with clustered metabolic risk in youth.

METHODS

In 2005-2006, a cohort of 9- and 15-yr-olds (N = 2818) was randomly selected from all regions of Norway. The participation rate was 89% and 74% among the 9-and 15-yr-olds, respectively. We assessed muscular strength by measuring explosive, isometric, and endurance strength. Cardiorespiratory fitness was measured directly as peak oxygen uptake during a cycle ergometry test. Risk factors included in the composite risk factor score (sum of z-scores) were systolic blood pressure, triglyceride, high-density lipoprotein cholesterol, insulin resistance, and waist circumference.

RESULTS

Muscle fitness was negatively associated with clustered metabolic risk, independent of cardiorespiratory fitness, and after adjustment for age, sex, and pubertal stage (beta = -0.112, P < 0.001). Independent of muscle fitness, an inverse association was found between cardiorespiratory fitness and clustered metabolic risk (beta = -0.337, P < 0.001). Moreover, the odds ratios for having clustered risk in the least fit quartile compared with the most fit quartile were 7.2 (95% confidence interval (CI)=4.3-12.0) and 17.3 (95% CI = 9.2-32.7) for muscle fitness and cardiorespiratory fitness, respectively.

CONCLUSIONS

Our results show that muscle fitness and cardiorespiratory fitness are independently associated with metabolic risk in youth.

Obesity and metabolic syndrome in 7-9 years-old Portuguese schoolchildren

BACKGROUND

Body fat is related to changes in lipid profile, blood pressure and metabolism of insulin and glucose, known as the metabolic syndrome (MS). The aim of this study was to estimate the prevalence of metabolic syndrome (MS) and its components among overweight and obese Portuguese schoolchildren, and to identify associated clinical and biochemical characteristics.

METHODS

A total of 82 children (14 overweight and 68 obese; 40 boys and 42 girls) aged 7-9 years, underwent anthropometric measurements. A blood sample was obtained to assess biochemical parameters. Insulin resistance (IR) was determined by the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR). MS was defined by the National Cholesterol Education Program Adult Treatment Panel III criteria modified by Cook.

RESULTS

The prevalence of MS was 15.8%. Abdominal obesity was present in all children. Frequency of elevated blood pressure, low HDL-cholesterol and elevated triglyceride concentrations were 62.6%, 13.4% and 11.0%, respectively. None of the children presented impaired fasting glucose, however hyperinsulinemia (7.3%) and IR (8.5%) were observed. The number of components of MS was higher in children with higher z-BMI (rho = 0.411; p < 0.001). MS was associated with higher leptin concentrations. No association was found with adiponectin or ghrelin levels. Leptin correlated positively with obesity, glucose metabolism, lipid profile, hepatic function and C-reactive protein, and negatively with HDL and Apolipoprotein A-I/B ratio.

CONCLUSIONS

This study shows a significant prevalence of MS among obese schoolchildren. Abdominal obesity and elevated blood pressure were the most frequent components of this syndrome. Dyslipidemia, IR and high levels of leptin were also associated with MS in this young group.

Metabolic syndrome in overweight children from the city of Botucatu - São Paulo State - Brazil: agreement among six diagnostic criteria

BACKGROUND

The metabolic syndrome has been described in children; however, a standard criterion has not been established for its diagnosis. Also, few studies have been conducted to specifically observe the possible existence of agreement among the existing diagnostic criteria. The purpose of the study is to evaluate agreement concerning prevalence rates of the metabolic syndrome diagnosed by six different criteria in overweight schoolchildren in the city of Botucatu - SP -Brazil.

METHODS

This is a cross-sectional study on 128 overweight schoolchildren. Clinical examination included anthropometry, pubertal staging evaluation, and blood pressure. Triacylglycerol, glycemia, HDL-cholesterol, insulin levels, and HOMA-IR were determined. The Kappa index, the Mann-Whitney test and the chi-square test were used for statistical analysis.

RESULTS

The prevalence of the metabolic syndrome varied from 10 to 16.5% according to different diagnostic criteria. Results were similar for boys and girls and pubertal stage. Great agreement was observed among the six different diagnostic criteria for the metabolic syndrome.

CONCLUSIONS

Different diagnostic criteria, when adopted for subjects with similar demographic characteristics, generate similar and compatible prevalence. Results suggest that it is possible to adopt any of the analyzed criteria, and the choice should be according to the components available for each situation.

Insulin resistance and metabolic syndrome in the pediatric population

The metabolic syndrome is a constellation of specific anthropometric, physiological, and biochemical abnormalities predisposing affected individuals to the development of diabetes and cardiovascular disease. The syndrome is well described in the adult literature. However, its description in the pediatric literature is more limited. Due in large part to the normal physiological changes that occur in children and adolescents with respect to growth and puberty, investigators have also struggled to establish a standard definition of the syndrome in the pediatric age group, hindering coordinated research efforts. However, whatever definition of the syndrome is used, the prevalence of the metabolic syndrome in the pediatric age group has increased worldwide. Insulin resistance is the principal metabolic abnormality that is common to the development of the metabolic syndrome in both children and adults. This review summarizes current research regarding the pathophysiology of insulin resistance and how this may contribute to specific abnormalities seen in children and adolescents with the metabolic syndrome. Specifically, insulin resistance in pediatric patients is correlated with cardiovascular risk factors such as elevated blood pressure, dyslipidemia, and type 2 diabetes mellitus, all of which are significant risk factors for adult disease. In addition, current treatment and prevention strategies, including lifestyle modifications, pharmacologic agents, and certain surgical therapies, are highlighted. The need for collaborative changes at the family, school, city, state, and national levels to address the growing prevalence of the metabolic syndrome in the pediatric age group is also reviewed.

Association of R230C ABCA1 gene variant with low HDL-C levels and abnormal HDL subclass distribution in Mexican school-aged children

BACKGROUND

The effect of ABCA1 genetic variation on HDL-C levels has been widely documented, although studies in children are scarce. We recently found a frequent non-synonymous ABCA1 variant (R230C) exclusive to populations with Native American ancestry, associated with low HDL-C levels and other metabolic traits in adults.

METHODS

We genotyped R230C variant in 1253 healthy unrelated Mexican school-aged children aged 6-15 years (595 boys and 658 girls) to seek associations with HDL-C levels and other metabolic traits. HDL subclass distribution was analyzed in a subgroup of 81 age, gender and BMI-matched children.

RESULTS

Individuals carrying the C230 allele showed a significantly lower HDL-C levels (P=2.9x10(-8)), and higher TC/HDL-C ratio, BMI, BMI z-score and percent fat mass (P=0.001, 0.049, 0.032 and 0.039, respectively). HDL size was smaller in R230C heterozygotes as compared to R230R homozygotes (P<0.05). Moreover, the proportion of HDL(2b) was lower, while the proportion of HDL(3a) and HDL(3b) particles was higher in R230C heterozygous and/or C230C homozygous individuals as compared to R230R homozygotes (P<0.05).

CONCLUSIONS

Our data suggest that the R230C ABCA1 gene variant plays an important role in HDL-C level regulation and HDL subclass distribution in healthy Mexican school-aged children.

Metabolic syndrome in obese adolescents

Childhood and adolescent obesity is highly prevalent and a relevant public health problem in Chile. Metabolic syndrome (MS), which is predictive of future cardiovascular disease and type 2 diabetes, has been associated with childhood obesity and insulin resistance. The aim of this study was to determine the prevalence of MS in a non-consultant obese adolescent population and to assess the underlying factors for the MS in these subjects. The nutritional status was evaluated for 25,102 students from 10 to 18 years of age living in Concepcin and Coronel, Chile. A total of 2,308 adolescents were found to be obese (BMI > or = 95 percentile). Metabolic syndrome was defined as the presence of at least three of the following abnormalities: waist circumference > or = 90th percentile, blood pressure > or= 90th percentile, fasting glycaemia > or = 100 mg/dL, HDL-cholesterol < or = 40 mg/dL and triglycerides > or = 110 mg/dL in a representative sample of 461 adolescents. The results obtained indicate that the prevalence of obesity was 9.2% and that MS reached 37.5%. Only 4.1% of the adolescents failed to present any of the risk factors for MS. When compared with the adolescents without MS, the estimated odd ratios (OR) for the presence of the characteristics of MS were all statistically significant, with increased waist circumference reaching an OR of 21.56. A significant difference was found between adolescents with and without MS; the parameters indicated greater insulin resistance for adolescents with MS. In conclusion, MS is highly prevalent among Chilean adolescents with obesity and its prevention beginning in childhood needs to be addressed.