Relation between visceral fat and disease risk in children and adolescents

Sexual dimorphism of adiposity and fat distribution among children and adolescents (8-18 year olds) from Poland

OBJECTIVES

The study aimed to analyze the sexual dimorphism of total body fat [BF%] and fat distribution among 8-18 year olds from Poland.

METHODS

The study included 2175 participants, divided into sex and age groups. Waist and hip circumferences, the thickness of six skinfolds, waist-to-hips ratio [WHR], the ratio of abdominal-to-suprailiac skinfolds, and the limb-to-trunk adiposity index were analyzed. Fat percentage were measured with a body composition analyzer (Tanita) with accuracy 0.1%. The Mollison's Index [MI] was used for calculating sexual dimorphism.

RESULTS

The value of MI for the WHR and its components (waist and hip circumferences) was negative (the boys were characterized by higher values of these parameters). The magnitude of the sex differences was lower in the younger age groups and the highest in the oldest groups. For adiposity [BF%], the average values were higher in females. In the younger age groups, girls had thicker skinfolds compared to boys, and this tendency was also observed in the older age groups, except for abdominal and suprailiac skinfolds. The values of the analyzed adiposity indicators also represented a tendency toward central allocation of fat tissue in boys.

CONCLUSIONS

In conclusion, sexual dimorphism of fat distribution and adiposity could be detected as early as 7 years of age. These differences can be identified using simple anthropometric methods, which are relatively cheap and easy to use, particularly in the field setting and large populations. The observation of changes in these features in children should be a recommended procedure aimed at early detection of overweight, obesity, as well as normal weight obesity or other metabolic disorders.

Sex and obesity status modify the association between vitamin D and eczema among adolescents

BACKGROUND

Epidemiologic studies have reported inconsistent associations between vitamin D and eczema. This study sought to assess whether sex and obesity status could modify the association between vitamin D and eczema.

METHODS

A cross-sectional study enrolled 763 adolescents in Kuwait. 25-hydroxyvitamin D (25(OH)D) was measured in venous blood. Current eczema was defined according to clinical history and characteristic morphology and distribution.

RESULTS

In sex-stratified analysis, decreased 25(OH)D levels were associated with increased current eczema prevalence among males (adjusted odds ratio (aOR)tertile 1 vs. tertile 3: 2.14, 95% confidence intervals (CI): 1.07-4.56), but not among females (aORtertile 1 vs. tertile 3: 1.08, 95% CI: 0.71-1.66). Further stratification by obesity status showed that lower 25(OH)D levels were associated with increased current eczema prevalence among overweight/obese males (per 10-unit decrease in 25(OH)D levels: aOR: 1.70, 95% CI: 1.17-2.46). Such an association was weaker and statistically non-significant among overweight/obese females (per 10-unit decrease in 25(OH)D levels: aOR: 1.26, 95% CI: 0.93-1.70).

CONCLUSIONS

Sex and obesity status modified the association between vitamin D levels and eczema, with an inverse association observed among overweight/obese males, but not among overweight/obese females. These results suggest that preventive and clinical management strategies could vary by sex and obesity status.

IMPACT

The current study showed that sex and obesity modify the association between vitamin D and eczema among adolescents. An inverse association between vitamin D and eczema was observed among overweight/obese males, but this association was not as pronounced among overweight/obese females. Vitamin D was not associated with eczema among underweight/normal weight males and females. The identification of effect modification by sex and obesity status add to the current scientific knowledge and further highlight the complexity of the association between vitamin D and eczema. These results may promote a more individualized approach to the future prevention and clinical management of eczema.

Association of Hepatic Steatosis with Adipose and Muscle Mass and Distribution in Children

Background: Pediatric studies have shown associations between hepatic steatosis and total body fat, visceral fat, and lean mass. However, these associations have not been assessed simultaneously, leaving their relative importance unknown. Objective: To evaluate associations between hepatic steatosis and total-body adiposity, visceral adiposity, and lean mass in children. Method: In children at risk for fatty liver, hepatic steatosis, adipose, and lean mass were estimated with magnetic resonance imaging and dual-energy X-ray absorptiometry. Results: Two hundred twenty-seven children with mean age 12.1 years had mean percent body fat of 38.9% and mean liver fat of 8.4%. Liver fat was positively associated with total-body adiposity, visceral adiposity, and lean mass (P < 0.001), and negatively associated with lean mass percentage (P < 0.001). After weight adjustment, liver fat was only positively associated with measures of central adiposity (P < 0.001). Visceral adiposity also had the strongest association with liver fat (P < 0.001). Conclusions: In children, hepatic steatosis is more strongly associated with visceral adiposity than total adiposity, and the association of lean mass is not independent of weight or fat mass. These relationships may help guide the choice of future interventions to target hepatic steatosis.

Gestational and childhood phthalate exposures and adolescent body composition: The HOME study

BACKGROUND

Early life phthalate exposures may disrupt metabolism but results from human studies are inconsistent and few have examined body composition during adolescence. We investigated associations of gestational and childhood urinary phthalate biomarker concentrations with body composition at age 12 years.

METHODS

We used data from 206 mother-child pairs in a prospective pregnancy and birth cohort enrolled in Cincinnati, OH from 2003 to 2006. We measured nine phthalate metabolites in spot urine samples collected twice from mothers during pregnancy and up to seven times from children at 1, 2, 3, 4, 5, 8, and 12 years. At age 12 years, we assessed fat and lean mass of the whole body and android and gynoid subregions, and visceral fat area with dual x-ray absorptiometry, and calculated android to gynoid %fat ratio and age- and sex-standardized fat and lean mass index z-scores. Using a multiple informant model, we estimated covariate-adjusted associations between urinary phthalate biomarker concentrations at each time period and outcomes at age 12 years. We assessed effect measure modification by child sex using stratified models.

RESULTS

Generally, urinary mono-benzyl phthalate (MBzP) concentrations were modestly associated with lower fat and lean mass. Each 10-fold increase in urinary MBzP concentrations during gestation and at ages 5 and 8 years was associated with a -0.34 (95%CI: -0.72, 0.05), -0.44 (95% CI: -0.83, -0.05), and -0.35 (95% CI: -0.71, 0.00) z-score difference in lean body mass index, respectively. Urinary monoethyl phthalate, mono-(3-carboxypropyl) phthalate, and summed di(2-ethylhexyl) phthalate metabolites were associated with greater lean mass at some exposure periods. Slightly weaker but similar patterns of association were found with other body composition measures; associations did not differ by child sex.

CONCLUSION

While most associations were weak, exposure to certain phthalates during gestation and childhood may be associated with adolescent body composition, particularly lean mass.

Trends in Abdominal Obesity and Central Adiposity Measures by Dual-Energy X-Ray Absorptiometry Among US Children: 2011-2018

OBJECTIVE

Previous studies that have reported trends on abdominal obesity among US children were usually based on anthropometric assessments. However, little is known about the recent trends in central adiposity measures by DXA and abdominal obesity since 2011-2012.

STUDY DESIGN

A serial cross-sectional analysis of US population-weighted data among children from NHANES 2011 to 2018 was conducted.

RESULTS

Between 2011-2012 and 2017-2018, there was a relatively stable trend among children aged 8-19 years in trunk fat and trunk fat percentage. During the same time periods, there were no significant changes in prevalence of abdominal obesity by waist circumference (18.6 vs. 21.1%) among those aged 2-19 years, and abdominal obesity by WHtR (34.1 vs. 36.2%) among those aged 6-19 years. However, a significant increase trend among boys aged 2-19 years was found in prevalence of abdominal obesity by waist circumference (16.1-22.7%; P = 0.004). For Mexican American youth and non-Hispanic Asian boys, there is a significant increase in mean trunk fat percentage and waist circumference.

CONCLUSION

Between 2011-2012 and 2017-2018, there have been no significant changes in central adiposity measured by DXA and prevalence of abdominal obesity among US children. Our study further supports that there is an urgent need to improve their lifestyle to reduce abdominal obesity for US children, especially for Mexican American youth and non-Hispanic Asian boys.

Breastfed and Formula-Fed Infants: Need of a Different Complementary Feeding Model?

Suboptimal nutrient quality/quantity during complementary feeding (CF) can impact negatively on infants’ healthy growth, even with adequate energy intake. CF must supplement at best human milk (HM) or formulas, which show nutritional differences. Considering this, a differentiated CF is probably advisable to correctly satisfy the different nutritional needs. To assess whether current needs at 6–24 months of age can still be met by one single CF scheme or different schemes are needed for breastfed vs. formula/cow’s milk (CM) fed infants, protein, iron and calcium intakes were assessed from daily menus using the same type and amount of solid food, leaving same amounts of HM and follow-up formula at 9 and again 18 months of age, when unmodified CM was added. Depending on the child’s age, calcium- and iron-fortified cereals or common retail foods were used. The single feeding scheme keeps protein intake low but higher than recommended, in HM-fed children while in formula/CM-fed ones, it achieves much higher protein intakes. Iron Population Recommended Intake (PRI) and calcium Adequate Intakes (AI) are met at the two ages only when a formula is used; otherwise, calcium-fortified cereals are needed. ESPGHAN statements on the futility of proposing different CF schemes according to the milk type fed do not allow to fully meet the nutritional recommendations issued by major Agencies/Organizations/Societies for all children of these age groups.

Waist-to-Height Ratio Is a Good Predictor of Metabolic Syndrome in Adolescents: A Report From the Thai National Health Examination Survey V, 2014

This study aimed to assess the performance of waist-to-height ratio (WHtR) in the prediction of metabolic syndrome and to determine the appropriate cutoff value in Thai adolescents. Demographic data, blood pressure, fasting blood glucose, and lipid profile were obtained from the Thai National Health Examination Survey V database. The performances of WHtR, waist circumference, body mass index (BMI), and BMI z-score were analyzed by the receiver operating characteristics. Among 2644 adolescents, metabolic syndrome was identified in 4.27%. The areas under the receiver operating characteristic curves of WHtR, waist circumference, BMI, and BMI z-score were comparable (0.924-0.960). Performance of WHtR was more constant across age groups compared with other parameters. Using the cutoff value of WHtR at 0.5 resulted in the sensitivity and specificity of 98.5%/83.4% and 88.9%/86.0% in males and females, respectively. In conclusion, the cutoff value of WHtR at 0.5 provided good sensitivity and specificity for identifying metabolic syndrome in both genders. However, the other clinical risk factors or more definite scores should be considered when further assessment.

Development of Visceral and Subcutaneous-Abdominal Adipose Tissue in Breastfed Infants during First Year of Lactation

This study aimed to investigate relationships between infant abdominal visceral and subcutaneous adiposity and human milk (HM) components and maternal body composition (BC) during first year of lactation. Subcutaneous-abdominal depth (SAD), subcutaneous-abdominal fat area (SFA), visceral depth (VD) and preperitoneal fat area of 20 breastfed infants were assessed at 2, 5, 9 and 12 months using ultrasound. Maternal BC was determined with bioimpedance spectroscopy. HM macronutrients and bioactive components concentrations and infant 24-h milk intake were measured and calculated daily intakes (CDI) determined. Maternal adiposity associated with infant SFA (negatively at 2, 5, 12, positively at 9 months, all overall p < 0.05). 24-h milk intake positively associated with infant SAD (p = 0.007) and VD (p = 0.013). CDI of total protein (p = 0.013), total carbohydrates (p = 0.004) and lactose (p = 0.013) positively associated with SFA. Lactoferrin concentration associated with infant VD (negatively at 2, 12, positively at 5, 9 months, overall p = 0.003). CDI of HM components and maternal adiposity have differential effects on development of infant visceral and subcutaneous abdominal adiposity. Maintaining healthy maternal BC and continuing breastfeeding to 12 months and beyond may facilitate favourable BC development reducing risk of obesity.

Visceral fat reduction and increase of intracellular fluid in weight loss participants on antihypertension medication

Objectives

Complex physiological interactions between hypertension and obesity contribute to and perpetuate a heightened morbidity and mortality. With the prevalence of both hypertension and obesity reaching epidemic proportions, we asked whether antihypertensive medications affect the ability of participants to achieve the same level of body composition improvements as other participants in a comprehensive weight loss program focused on reduction of visceral adipose tissue.

Methods

Data was analyzed from 2200 subjects completing a commercially available, expert supervised weight loss program including ~6 weeks of a proprietary, nutritionally complete, very low-calorie diet (VLCD) followed by a ~3-week structured transition back to a normal dietary intake. Overall, 33% of the subjects reported taking at least one prescription antihypertensive medication.

Results

Our data show participants in both groups (± antihypertensive drugs) achieved clinically relevant and statistically significant improvements in standard measures of weight loss and endpoints directly related to inflammation and hypertension.

Conclusion

A nonpharmacologic, nonsurgical VLCD-based weight loss and metabolic health program is capable of producing clinically meaningful improvements in body composition and physiological endpoints, including those linked to hypertension, cardiovascular disease and inflammation, and is as equally effective for adults taking prescription antihypertensives as it is for those participants who are not.

An Overview of the Role of Adipokines in Cardiometabolic Diseases

Obesity as an independent risk factor for cardiovascular diseases (CVDs) leads to an increase in morbidity, mortality, and a shortening of life span. The changes in heart structure and function as well as metabolic profile are caused by obese people, including those free of metabolic disorders. Obesity alters heart function structure and affects lipid and glucose metabolism, blood pressure, and increase inflammatory cytokines. Adipokines, specific cytokines of adipocytes, are involved in the progression of obesity and the associated co-morbidities. In the current study, we review the scientific evidence on the effects of obesity on CVDs, focusing on the changes in adipokines. Several adipokines have anti-inflammatory and cardioprotective effects comprising omentin, apelin, adiponectin, and secreted frizzled-related protein (Sfrp-5). Other adipokines have pro-inflammatory impacts on the cardiovascular system and obesity including leptin, tumor necrosis factor (TNF), retinol-binding protein4 (RBP-4), visfatin, resistin, and osteopontin. We found that obesity is associated with multiple CVDs, but can only occur in unhealthy metabolic patients. However, more studies should be designed to clarify the association between obesity, adipokine changes, and the occurrence of CVDs.

Resolution of Metabolic syndrome with reduction of visceral adipose tissue in a 47 year old patient with Type 2 Diabetes Mellitus

BACKGROUND AND AIMS

Metabolic syndrome (MetS), defined as a cluster of metabolic abnormalities including visceral adiposity, insulin resistance, hypertension, and dyslipidemia, now affects more than a third of adults in the United States highlighting the need for effective complementary approaches to current treatments.

METHODS

We present a case report of a 47-year-old man with a history of MetS and poorly controlled Type 2 Diabetes Mellitus (T2D) who completed a 20Lighter program (20L) including a very low calorie diet (VLCD). At the time of enrollment his BMI was 32.7, HbA1c was 9.6%, and prescription medication history included lisinopril, lovastatin, and metformin, glimepiride, and combination sitagliptin/metformin.

RESULTS

Fifteen weeks after beginning 20L (6 weeks after program completion) marked reduction of weight, visceral adipose tissue and normalization of HbA1C was seen, and all medications were withdrawn.

CONCLUSIONS

While longer follow-up is required, this case report shows that a comprehensive program including a relatively short period of nutritionally complete VLCD, followed by gradual return to moderate dietary lifestyle is capable of producing clinically significant improvements in health and quality of life in individuals with MetS and poorly controlled T2D.

Prevalence of abdominal obesity in non-obese adolescents: a North Indian adolescent study

Context Childhood obesity is defined based on body mass index (BMI) criteria. Asian adults have more abdominal adiposity as compared to Western people for an equivalent BMI. Similarly, children who are non-obese/overweight by BMI criteria may have abdominal obesity. It is important to identify and target this population to reduce future cardiovascular risk. Objective To evaluate and inter-relate the prevalence of obesity subtypes (generalized and abdominal) in school going adolescents. Methods A randomized cross-sectional community based study was conducted, which was carried out in 13 schools of Chandigarh, a North Indian city. 10,037 school going adolescents of age 10-18 years were evaluated. Results The prevalence of overweight and generalized obesity in present study was 9.3 and 4.9% respectively. Generalized obesity was observed in 4.2% of males and 5.7% of females (p-Value = 0.001). The abdominal obesity was noted in 5.4% of children and its prevalence increased progressively with age. The prevalence was highest in 16-18 years age-group (7.6%, p<0.001). 39.3% of abdominally obese subjects were not obese by BMI criteria, while prevalence of abdominal obesity in nonobese adolescents was 2.24%. It was more prevalent in females (3.7%) than males (3%, p=0.025). Prevalence of obesity was 7.9 and 1.8% in private and government schools respectively (p<0.001). Conclusions Abdominal obesity is more prevalent than generalized obesity and shows increasing trend with age. Interestingly, over one third of centrally obese adolescents are not obese by BMI criteria. This underlines the importance of waist circumference measurement in addition to BMI while assessing obesity.

Hepatic fat is a stronger correlate of key clinical and molecular abnormalities than visceral and abdominal subcutaneous fat in youth

INTRODUCTION

Body fat distribution is strongly associated with cardiometabolic disease (CMD), but the relative importance of hepatic fat as an underlying driver remains unclear. Here, we applied a systems biology approach to compare the clinical and molecular subnetworks that correlate with hepatic fat, visceral fat, and abdominal subcutaneous fat distribution.

RESEARCH DESIGN AND METHODS

This was a cross-sectional sub-study of 283 children/adolescents (7-19 years) from the Yale Pediatric NAFLD Cohort. Untargeted, high-resolution metabolomics (HRM) was performed on plasma and combined with existing clinical variables including hepatic and abdominal fat measured by MRI. Integrative network analysis was coupled with pathway enrichment analysis and multivariable linear regression (MLR) to examine which metabolites and clinical variables associated with each fat depot.

RESULTS

The data divided into four communities of correlated variables (|r|>0.15, p<0.05) after integrative network analysis. In the largest community, hepatic fat was associated with eight clinical biomarkers, including measures of insulin resistance and dyslipidemia, and 878 metabolite features that were enriched predominantly in amino acid (AA) and lipid pathways in pathway enrichment analysis (p<0.05). Key metabolites associated with hepatic fat included branched-chain AAs (valine and isoleucine/leucine), aromatic AAs (tyrosine and tryptophan), serine, glycine, alanine, and pyruvate, as well as several acylcarnitines and glycerophospholipids (all q<0.05 in MLR adjusted for covariates). The other communities detected in integrative network analysis consisted of abdominal visceral, superficial subcutaneous, and deep subcutaneous fats, but no clinical variables, fewer metabolite features (280, 312, and 74, respectively), and limited findings in pathway analysis.

CONCLUSIONS

These data-driven findings show a stronger association of hepatic fat with key CMD risk factors compared with abdominal fats. The molecular network identified using HRM that associated with hepatic fat provides insight into potential mechanisms underlying the hepatic fat-insulin resistance interface in youth.

Maternal gestational diabetes and infant feeding, nutrition and growth: a systematic review and meta-analysis

Gestational diabetes mellitus (GDM) is a major health problem, with increased risks of obesity and diabetes in offspring. However, little is known about the effect of GDM on infant feeding, nutrition and growth, and whether these factors play a role in mediating these risks. We systematically reviewed evidence for the effect of GDM on infant feeding, nutrition and growth. We searched MEDLINE, Web-of-Science, Embase, CINAHL and CENTRAL for studies that reported outcomes in infants <2 years who were and were not exposed to GDM. Studies of pre-gestational diabetes were excluded. Meta-analysis was performed for three epochs (1–6, 7–12, 13–24 months), using inverse-variance, fixed-effects methods. Primary outcomes were energy intake (kJ) and BMI (kg/m2). Twenty-five studies and 308 455 infants were included. Infants exposed to GDM, compared with those not exposed, had similar BMI at age 1–6 months (standardised mean difference (SMD) = 0·01, 95 % CI −0·04, 0·06; P = 0·69) and 7–12 months (SMD = 0·04, 95 % CI −0·01, 0·10; P = 0·09), reduced length at 1–6 and 7–12 months, increased whole-body fat at 1–6 months, higher rates of formula supplementation in hospital, shorter duration of breast-feeding and decreased rates of continued breast-feeding at 12 months. Breast milk of women with GDM had lower protein content. There was no association between GDM and infant weight and skinfold thickness. No data were available for nutritional intake and outcomes at 13–24 months. Low- or very low-quality evidence suggests GDM is not associated with altered BMI in infancy, but is associated with increased fat mass, high rates of formula use and decreased duration of breast-feeding.

Correlates of body fat and waist circumference in children from São Caetano do Sul, Brazil

The purpose of this study was to examine potential correlates of body fat (BF) and waist circumference (WC) in children. The sample included 328 children (169 boys) aged 9-11 years. BF (%) was measured using a bioelectrical impedance scale. WC measurements were made on exposed skin at the end of a normal expiration using a non-elastic anthropometric tape. Moderate-to-vigorous physical activity (MVPA) and sedentary behavior were measured using accelerometers. Participants with complete individual, family and home, and school environmental data were included in the analysis. Children averaged 21.3% in boys and 25.8% in girls for BF and 68.0 cm in boys and 67.2 cm in girls for WC. There was higher BF among girls (p<0.001), but no significant sex differences with respect to WC. In boys, breakfast consumption, bad sleep quality, and MVPA were associated with BF. Among girls, the only variables associated with BF were breakfast consumption and bad sleep quantity. Bad sleep quality and MVPA were associated with WC in boys. Among girls, WC was associated with breakfast consumption and bad sleep quantity. We identified correlates of BF and WC in children; however, few correlates were common for both BF and WC, and for both boys and girls.

Association of physical activity with adiposity in preschoolers using different clinical adiposity measures: a cross-sectional study

Background

More research is needed about the association between physical activity (PA), sedentary behaviour (SB), and adiposity in preschoolers, particularly using more direct clinical measures of adiposity. Therefore, the main objective of this study was to investigate the association between objectively measured PA and different clinical adiposity measures in a large sample of preschoolers.

Methods

Four hundred sixty-three predominantly normal-weight (77%) 2–6-year-old preschool children participated in the Swiss Preschoolers’ Health Study (SPLASHY). Physical activity was measured using accelerometers and was analyzed using 15-s (uni-axial) epoch length using validated cut-offs. Adiposity measures included body mass index (BMI), the sum of four skinfolds, and waist circumference (WC). Multilevel linear regression modeling, adjusted for age, sex and wear time, was used to assess the association between PA and SB with BMI, WC, and skinfold thickness.

Results

Total PA and different PA intensities were positively and SB was inversely associated with BMI in the total sample and in the normal-weight children (p < 0.05). Total PA was inversely associated with skinfold thickness in overweight and obese children (p < 0.05), while there was only a weak association for vigorous PA (p > 0.05). Moderate and moderate-to-vigorous PA were positively, and SB was negatively associated with WC in the total sample and in the normal-weight children (p < 0.05). Additional adjustment for potential sociocultural and biological confounding variables attenuated some of the results.

Conclusions

In this very young and predominantly normal-weight population, PA is positively related to BMI and WC, but this relationship is not observed in overweight and obese children. In this latter population, PA is inversely, and SB is positively related to skinfold thickness. Skinfold thickness could represent a useful and simple clinical measure of body fat in preschoolers. The role of vigorous PA in the prevention of early childhood obesity should be further investigated in future studies.

Trial registration

ISRCTN ISRCTN41045021. Retrospectively registered 06 May 2014.

A critical review of the role of milk and other dairy products in the development of obesity in children and adolescents

Existing reviews suggest that milk and other dairy products do not play a role in the development of obesity in childhood, but they do make an important contribution to children’s nutrient intake. It is thus curious that public health advice on the consumption of dairy products for children is often perceived as unclear. The present review aimed to provide an overview of the totality of the evidence on the association between milk and other dairy products, and obesity and indicators of adiposity, in children. Our search identified forty-three cross-sectional studies, thirty-one longitudinal cohort studies and twenty randomised controlled trials. We found that milk and other dairy products are consistently found to be not associated, or inversely associated, with obesity and indicators of adiposity in children. Adjustment for energy intake tended to change inverse associations to neutral. Also, we found little evidence to suggest that the relationship varied by type of milk or dairy product, or age of the children, although there was a dearth of evidence for young children. Only nine of the ninety-four studies found a positive association between milk and other dairy products and body fatness. There may be some plausible mechanisms underlying the effect of milk and other dairy products on adiposity that influence energy and fat balance, possibly through fat absorption, appetite or metabolic activity of gut microbiota. In conclusion, there is little evidence to support a concern to limit the consumption of milk and other dairy products for children on the grounds that they may promote obesity.

Estimation of visceral fat in 9- to 13-year-old girls using dual-energy X-ray absorptiometry (DXA) and anthropometry

OBJECTIVES

Accumulation of visceral fat (VF) in children increases the risk of cardiovascular disease and type 2 diabetes, and measurement of VF in children using computed tomography and magnetic resonance imaging (MRI) is expensive. Dual-energy X-ray absorptiometry (DXA) may provide a low-cost alternative. This study aims to determine if DXA VF estimates can accurately estimate VF in young girls, determine if adding anthropometry would improve the estimate and determine if other DXA fat measures, with and without anthropometry, could be used to estimate VF in young girls.

METHODS

Visceral fat was measured at lumbar intervertebral sites (L1-L2, L2-L3, L3-L4 and L4-L5) using 3.0T MRI on 32 young girls (mean age 11.3 ± 1.3 years). VF was estimated using the GE CoreScan application. Measurement of DXA android and total body fat was performed. Weight, height and waist circumference (WC) measurements were also obtained.

RESULTS

Waist circumference and body mass index were both strongly correlated with MRI, although WC was the best anthropometric covariate. Per cent fat (%fat) variables had the strongest correlation and did best in regression models. DXA %VF (GE CoreScan) and DXA android %fat and total body %fat accounted for 65% to 74% of the variation in MRI VF.

CONCLUSION

Waist circumference predicted MRI VF almost as well as DXA estimates in this population, and a combination of WC and DXA fat improves the predictability of VF. DXA VF estimate was improved by the addition of WC; however, DXA android %fat with WC was better at predicting MRI VF.

Hepatic steatosis is highly prevalent across the paediatric age spectrum, including in pre-school age children

BACKGROUND

The prevalence of non-alcoholic fatty liver disease (NAFLD) in children is 8% in the general population, and 34% in the context of obesity. There is a paucity of data on the prevalence of hepatic steatosis in healthy children in Ontario.

AIMS

To determine the prevalence of hepatic steatosis using abdominal computed tomography (CT) scans in a cohort of previously healthy children across the paediatric age spectrum in Ontario, Canada, and to determine any association between measures of abdominal adiposity and hepatic steatosis.

METHODS

Retrospective review of the SickKids Trauma Database from 2004-2015. Previously healthy children ages 1-17 years having undergone an abdominal CT scan as a part of routine trauma assessment were included, and those with an intra-abdominal injury excluded. Steatosis was defined as a difference between liver and spleen attenuation ≤-25HU. The percentage of the total area occupied by abdominal subcutaneous adipose and visceral adipose tissue was measured. Anthropometrics and baseline demographics were collected.

RESULTS

A total of 503 (51% male) children with mean (±SD) age 9.5 ± 4.5 years and weight z-score of 0.37 ± 1.05 were studied. Seventy-seven (15%, 95% CI [12%-18%]) had hepatic steatosis; no differences found between sexes or across age quartiles. The abdominal subcutaneous adipose tissue area was greater in those with hepatic steatosis compared to those without (32% [22-42] vs 24% [17-36], P = 0.003). The visceral adipose tissue area was significantly greater in older children ≥9.8 years with hepatic steatosis (7.7% [5.1-10] vs 6.6% (4.9-8.5), P = 0.04).

CONCLUSION

Hepatic steatosis was highly prevalent in previously healthy children in Ontario, including children of pre-school age. We found an association between hepatic steatosis and abdominal subcutaneous adipose tissue, and in older children with visceral adipose tissue.

The Associations between Adiposity, Cognitive Function, and Achievement in Children

Although obesity has been related to measures of academic achievement and cognition in children, the influence of fat distribution, specifically visceral adiposity, on select aspects of achievement and cognitive function remains poorly characterized among preadolescent children.

PURPOSE

The aim of this study was to evaluate the relation of adiposity, particularly visceral adipose tissue (VAT), on achievement and cognitive function among children.

METHODS

Children with obesity (ages 8-9 yr old, N = 55, 35 females) completed cognitive and academic tests. Normal weight children (N = 55, 35 females) were matched to this group on demographic characteristics and aerobic fitness. Covariate analyses included age, Brief Intellectual Ability, socioeconomic status, and fat-free V˙O2 (V˙O2 peak adjusted for lean mass; mL·kg lean·min). Adiposity (i.e., whole body percent fat, subcutaneous abdominal adipose tissue, and VAT) was assessed using dual-energy x-ray absorptiometry.

RESULTS

The results of this study revealed that, relative to their normal weight counterparts, children with obesity had significantly lower performance on tests of reading and math. Analyses revealed that among children with obesity, %Fat and subcutaneous abdominal adipose tissue were not related to cognitive abilities. However, higher VAT was associated with poorer intellectual abilities (Ps ≤ 0.04) and cognitive performance (i.e., thinking ability and cognitive efficiency, Ps ≤ 0.04). However, among normal weight children, VAT was positively associated with intellectual abilities and cognitive efficiency.

CONCLUSION

In conclusion, the results suggest that VAT was selectively and negatively related with cognition among children with obesity. Along with the dangerous metabolic nature of VAT, its detrimental relationship with obese children's intellectual and cognitive functioning is concerning.

Risk Factors for Obesity and Overfat among Primary School Children in Mashonaland West Province, Zimbabwe

Associated childhood obesity risk factors are not well established in developing countries such as Zimbabwe and this information is essential for tailored intervention development. This study aimed to identify prominent risk factors for overweight/obese and overfat/obese among primary school children of Mashonaland West Province in Zimbabwe. A school-based cross-sectional study was conducted using multi-stage random cluster sampling approach (30 × 30). Bivariate and multivariable logistic regression was employed and identified the risk factors for overweight/obese and overfat/obese. A total of 974 participants were enrolled in the study. Prominent significant risk factors of overweight/obese after multivariable adjustment were higher socio-economic households; parental diabetes status; and living in Makonde, Zvimba, Sanyati or Mhondoro-Ngezi district as opposed to Hurungwe district. Risk factors for overfat/obese that remained statically significant were children in urban areas (aOR = 3.19, 95% CI: 2.18-4.66, p = 0.000), being one child in a household, and parents who have diabetes mellitus. Living in Makonde, Sanyati, and Zvimba district remained associated with overfat/obese compared to Hurungwe district. This study has identified prominent proximal determinants of overweight/obese and overfat/obese among primary school children in Zimbabwe, to better assist policy guidance. Aggressive education on good nutrition activities should be tailored and targeted to most affected urban areas within high-risk districts.

Impact of Early Infant Growth, Duration of Breastfeeding and Maternal Factors on Total Body Fat Mass and Visceral Fat at 3 and 6 Months of Age

BACKGROUND

Accelerated gain in fat mass in the first months of life is considered to be a risk factor for adult diseases, given the tracking of infancy fat mass into adulthood. Our objective was to assess the influence of early growth, type of feeding and maternal variables on fat mass in early life.

METHODS

In 300 healthy term infants, we longitudinally measured fat mass percentage (FM%) by air-displacement-plethysmography at 1, 3, and 6 months and abdominal visceral and subcutaneous fat measured by ultrasound at 3 and 6 months.

RESULTS

Both gain in FM% and weight-for-length in the first 3 months were positively associated with FM% at 6 months of age and visceral fat at 3 months of age. Gain in FM% and weight-for-length between 3 and 6 months were both positively associated with visceral fat at 6 months. Breastfeeding duration associated positively with subcutaneous fat but not with visceral fat at 3 and 6 months. Maternal characteristics did not associate with FM% or visceral fat at 3 or 6 months.

CONCLUSION

Higher gain in FM% or in weight-for-length in the first postnatal months leads not only to higher FM% but also more to accumulation of visceral fat. Exclusive breastfeeding appears to promote subcutaneous but not visceral fat in the first 6 months.

Metabolic syndrome's risk factors and its association with nutritional status in schoolchildren

The metabolic risk factors (RF) to the diagnosis of metabolic syndrome (MetS) have been evidenced at early ages, including children. The aim of the present study was to identify the prevalence of RF to the diagnosis of MetS and its association with nutritional status of schoolchildren from 6 to 10 years old. A cross-sectional study was carried out in 505 students of municipal schools in Macae, Brazil, conducted from 2013 to 2014. The RF evaluated were: blood pressure (mm Hg), triglycerides (mmol/L), HDL-cholesterol (mmol/L) fasting glucose (mmol/L) and waist circumference (cm). At least one RF was present in 61% (n = 308) of the sample. By nutritional status, there was higher prevalence of RF in overweight/obese schoolchildren compared to those with normal weight, except in the concentration of HDL-c. The prevalence of one, two and three RF (MetS) were 34.7% (n = 175), 21.0% (n = 106) and 5.3% (n = 27), respectively. Two RF were more present in overweight (28.2% 95%CI 19.0; 39.0) and obese (41.5% 95%CI 31.4; 52.1) compared to normal weight children (13.5% 95%CI 9.9; 17.8). Three or more RF were more frequent among obese (25.5% 95%CI 17.0; 35.5) in relation to overweight (2.4% 95%CI 0.2; 8.2) and normal weight children (0.3% 95%CI 0; 1.7). The data indicate high prevalence of RF and its relationship with the magnitude of body weight excess. Therefore, the identification and early treatment of these RF might minimize the risk of MetS and related diseases.

Neck Circumference-Height Ratio as a Predictor of Sleep Related Breathing Disorder in Children and Adults

STUDY OBJECTIVES

While neck circumference (NC) is a useful predictor of obstructive sleep apnea (OSA) in adults, childhood OSA is difficult to predict clinically. We utilized the neck circumference-height ratio (NHR) to normalize NC in growing children. Our study aimed to determine if (1) NC is a reproducible clinical measurement; (2) NHR predicts OSA in children; (3) this metric translates to adults.

METHODS

For this retrospective study, paired NC measurements (from clinic and sleep laboratory) in 100 consecutive adult subjects were used to confirm inter-observer reproducibility. Polysomnographic (PSG) and anthropometric data from children aged 5-18 years presenting consecutively between July 2007 and February 2012 was obtained. Children with genetic syndromes, severe neurological disorders, craniofacial abnormalities, tracheostomy, past adenotonsillectomy, in-hospital PSG or sleep efficiency < 80% were excluded. Data were analyzed using χ(2) test and logistic and linear regression models. These analyses were also applied to 99 adult patients with similar exclusion criteria.

RESULTS

Adult NC measurement had inter-observer correlation of 0.85 (N = 100). Among children, after correcting for BMI-Z scores, NHR conferred additional predictive value, in both logistic regression and linear models, for both apnea-hypopnea index (AHI) > 2 and > 5 (N = 507). In children, for NHR > 0.25, the odds ratio of AHI > 2 was 3.47. In adults, for NHR > 0.25, the odds ratio of AHI > 5 was 18.

CONCLUSIONS

NHR can be included as a simple screening tool for OSA in children and adults, which along with other predictors, may improve the ability of clinicians to triage children and adults at risk for OSA for further evaluation with PSG.

Dexa Body Composition Assessment in 10-11 Year Healthy Children

Introduction

Obesity is a growing health problem associated with metabolic derangements and cardiovascular disease. Accumulating evidence links the accumulation of visceral adipose tissue (VAT) to these obesity related health risks in adults. Childhood obesity is associated with a lifetime risk of cardiovascular disease and poses a serious challenge to future health care. In children, there is much less data on the prevalence and gender differences of visceral obesity than in adults. This study aims to provide reference values for VAT in children 10–11 years of age.

Methods

In a cross-sectional study performed in the north western part of theNetherlands, healthy children of 10–11 years of age, were recruited from primary schools. Anthropometric data consisting of height, weight, waist circumference (WC) and BMI were measured. Body composition was measured using DXA, providing measures for bone mineral content, total fat mass (TFM), lean body mass (LBM) and VAT.

Results

217 children were eligible for this study. Girls appeared to have a greater TFM (31.4% vs 27.5% of total body weight (TBW); P < .01) but lower VAT (0.3% vs 0.5% of TBW;P < .01) than boys, whereas boys had higher LBM (65.4% vs 69.3% TBW;P < .01). Median VAT area (cm²) was 41.1 for boys and 22.4 for girls (P < .01). Moderate to strong correlations were found for WC and BMI with VAT (boys: r = .664 and r = .630; Girls r = .699 and r = .546 respectively all P < .001).

Discussion

This study shows gender specific differences in VAT percentiles in healthy non-obese 10–11 year old children as measured by DXA that may serve as reference values in children. Independent of BMI and WC, girls tend to have more TFM but less VAT and LBM than boys.

Association of hypertriglyceridemic-waist phenotype with liver enzymes and cardiometabolic risk factors in adolescents: the CASPIAN-III study

OBJECTIVE

This study aims to investigate the role of metabolic syndrome (MetS) and the hypertriglyceridemic-waist (HW) phenotype in determining cardiometabolic risk factors and elevated liver enzymes in a national sample of Iranian pediatric population.

METHOD

This nationwide study was conducted in the framework of the third survey of a surveillance program. Students, aged 10-18 years, were recruited from 27 provinces in Iran. The prevalence of cardiometabolic risk factors was compared in students with and without HW and MetS. The association of HW with different cardiometabolic risk factors was determined.

RESULTS

The mean age of studied population was 14.73±2.41 years. Prevalence of HW and MetS was 3.3% and 4%, respectively. Sixty-nine (71.1%) participants with HW had MetS. The prevalence of obesity, elevated systolic blood pressure, hypercholesterolemia, and elevated alanine aminotransaminase (ALT) was significantly higher in subjects with HW phenotype and MetS than in their peers (p<0.05). A significant association was observed between HW and elevated levels of cholesterol and ALT, as well as between obesity and low HDL-C (p<0.05).

CONCLUSIONS

The current findings serve as complementary evidence to previous studies, which have been mainly conducted among adults, suggesting that the HW phenotype is associated with cardiometabolic risk factors, especially with elevated cholesterol and ALT. The authors propose that, in primary care settings and in large epidemiological studies, the measurement of all MetS components can be replaced by studying HW as a screening tool for identifying children at high risk for cardiometabolic disorders.

Fat Imaging via Magnetic Resonance Imaging (MRI) in Young Children (Ages 1-4 Years) without Sedation

Introduction

This pilot study developed techniques to perform Magnetic Resonance Imaging (MRI) of specific fat deposition in 18 children (age 18 months to 4 years).

Methods

The children engaged in a series of practice tests to become acclimated to the scanner noises, reduce claustrophobia, and rehearse holding still for a set time. The practice tests assessed if the child could remain still for two minutes while watching a video, first while lying on a blanket, second, on the blanket with headphones, and third, in the mock scanner. The children who passed the three practice tests were then scanned with a 3T Siemens Skyra magnet. Abdominal fat distribution (region of interest (ROI) from the top of the ileac crest to the bottom of the ribcage) volume was measured using 2-point DIXON technique. This region was chosen to give an indication of the body composition around the liver.

Results

Twelve out of eighteen participants successfully completed the actual MRI scan. Chi-squared test showed no significant difference between male and female pass-fail rates. The median age of completed scans was 36 months, whereas the median age for children unable to complete a scan was 28 months. The average total trunk fat was 240.9±85.2mL and the average total VAT was 37.7±25.9mLand liver fat was not quantifiable due to physiological motion. Several strategies (modeling, videos, and incentives) were identified to improve pediatric imaging in different age ranges.

Conclusion

Using an age-specific and tailored protocol, we were able to successfully use MRI for fat imaging in a majority of young children. Development of such protocols enables researchers to better understand the etiology of fat deposition in young children, which can be used to aid in the prevention and treatment of adiposity.

Development of waist circumference percentiles for Japanese children and an examination of their screening utility for childhood metabolic syndrome: a population-based cross-sectional study

BACKGROUND

In Japan, waist circumference (WC) percentiles to screen for childhood metabolic syndrome (MetS) are unavailable. The objectives of this study were to develop WC and WC-to-height ratio (WC/Ht) percentile curves by age and sex for Japanese children, and to test their utility in screening for MetS in children with obesity who are otherwise healthy.

METHODS

The WC and WC/Ht percentiles were developed using the LMS method of summarizing growth standards, which monitors changing skewness (L), medians (M), and coefficients of variation (S) in childhood distributions. A representative dataset was used, which consisted of 3,634 boys and 3,536 girls aged 4.5-12.75 years in Shizuoka prefecture, Japan, between 2010 and 2012. Children who were obese (355 boys and 230 girls) aged 6-12 years from Osaka prefecture, Japan, were screened for childhood MetS using the new percentiles and the International Diabetes Federation's (IDF's) definition of MetS.

RESULTS

The number of participants with certain metabolic abnormalities (high systolic and diastolic blood pressure, and a high level of triglycerides) was significantly higher in boys aged 10-12 years, with a WC ≥ 90th percentile, than among those with a WC < 90th percentile. None of the participants with a WC < 90th percentile exhibited two or more metabolic abnormalities, regardless of their age or sex. Among the participants aged 10-12 years, 11.4 % of boys and 4.4 % of girls with a WC ≥ 90th percentile were diagnosed with MetS.

CONCLUSIONS

The new percentiles may have a certain level of potential to screen Japanese children for childhood MetS in accordance with the IDF definition.

Reliability tests and guidelines for B-mode ultrasound assessment of central adiposity

INTRODUCTION

Ultrasound represents a validated and relatively inexpensive diagnostic device for assessing central adiposity; however, widespread adoption has been impeded by the lack of reliable standard operating procedures.

PURPOSE

To examine the reliability of, and describe guidelines for, ultrasound-derived recording of intra-abdominal fat thickness (IAT) and maximal preperitoneal fat thickness (PFT).

METHODS

Ultrasound scans were obtained from 20 adults (50% female, 26 ± 7 years, 24·5 kg/m(2) ) on three different mornings. IAT was assessed 2 cm above the umbilicus (transverse plane) measuring from linea alba to: (i) anterior aorta, (ii) posterior aorta and (iii) anterior aspect of the vertebral column. PFT was measured from linea alba to visceral peritoneum in (i) sagittal and (ii) transverse planes, immediately over and inferior to the xiphi-sternum, respectively.

RESULTS

For IAT, the criterion intraclass correlation coefficient (ICC) of 0·75 was exceeded for measurements to anterior aorta (0·95), posterior aorta (0·94) and vertebra (0·96). The reliability coefficient expressed as a percentage of the mean (RC%) was lowest (better) for measurement to vertebrae (9·8%). For PFT, mean thickness was comparable for sagittal (1·74 cm) and transverse (1·76 cm) planes; ICC values were also comparable for both planes (0·98 vs. 0·98, respectively), as were RC% (7·5% vs. 7·1%, respectively).

CONCLUSIONS

IAT assessments to the vertebra were marginally more reliable than those to other structures. While PFT assessments were equally reliable for both measurements planes, precise probe placement was easier for the sagittal plane. Based on these findings, guidelines for the reliable measurement of central adiposity using ultrasound are presented.

Prospective associations of eating behaviors with weight gain in infants

OBJECTIVE

To examine whether maternal reports of infant eating behaviors are stable over time and whether eating behaviors are prospectively associated with weight gain.

METHODS

In an ongoing study of infant growth, weight and length were measured at 2 weeks, 3 months, and 5 months of age. Food responsiveness (FR), satiety responsiveness (SR), enjoyment of feeding (EF), and slow eating (SE) were assessed with the Baby Eating Behavior Questionnaire. Repeated measures ANOVA was used to examine changes in eating behaviors from 2 weeks to 5 months. Simple Pearson correlations examined associations among eating behaviors across time and associations of eating behaviors with subsequent change in weight-for-length z-scores.

RESULTS

Among 31 infants studied from 2 weeks to 3 months, FR and SR remained consistent (P < 0.05), and among 21 infants studied from 3 to 5 months, FR, EF, and SE were consistent (P < 0.01). Infants ate more quickly (P < 0.01) and tended to have greater SR with age (P = 0.09). Only SE at 3 months was associated with subsequent gain in weight-for-length (P < 0.05).

CONCLUSIONS

Consistent with previous research, SE was predictive of weight gain during infancy. Given that eating behaviors were largely consistent after 3 months of age, it may be important to encourage the development of healthy eating behaviors during early infancy.

Best single-slice location to measure visceral adipose tissue on paediatric CT scans and the relationship between anthropometric measurements, gender and VAT volume in children

OBJECTIVE

Visceral adipose tissue (VAT) is a significant risk factor for obesity-related metabolic diseases. This study investigates (1) the best single CT slice location for predicting total abdominal VAT volume in paediatrics and (2) the relationship between waist circumference (WC), sagittal diameter (SD), gender and VAT volume.

METHODS

A random sample of 130 paediatric abdomen CT scans, stratified according to age and gender, was collected. Three readers measured VAT area at each intervertebral level between T12 and S1 using ImageJ analysis (National Institute of Health, Bethesda, MD) software by thresholding -190 to -30 HU and manually segmenting VAT. Single-slice VAT measurements were correlated with total VAT volume to identify the most representative slice. WC and SD were measured at L3-L4 and L4-L5 slices, respectively. Regression analysis was used to evaluate WC, SD and gender as VAT volume predictors.

RESULTS

Interviewer and intraviewer reliability were excellent (intraclass correlation coefficient = 0.99). Although VAT measured at multiple slices correlated strongly with abdominal VAT, only one slice in females at L2-L3 and two slices in males at L1-L2 and L5-S1 were strongly correlated across all age groups. Linear regression analysis showed that WC was strongly correlated with VAT volume (beta = 0.970, p < 0.001).

CONCLUSION

Single-slice VAT measurements are highly reproducible. Measurements performed at L2-L3 in females and L1-L2 or L5-S1 in males were most representative of VAT. WC is indicative of VAT.

ADVANCES IN KNOWLEDGE

VAT should be measured at L2-L3 in female children and at either L1-L2 or L5-S1 in males. WC is a strong indicator of VAT in children.

Fitness is a determinant of the metabolic response to endurance training in adolescents at risk of type 2 diabetes mellitus

OBJECTIVE

The purpose of this prospective cohort study was to determine whether changes in cardiorespiratory fitness are associated with the metabolic response to endurance training in adolescents at risk of type 2 diabetes mellitus (T2DM).

METHODS

Seventy-three overweight and obese adolescents completed a 6-month endurance exercise intervention. Total fat mass, trunk fat mass, visceral adipose tissue, and liver fat were assessed with dual energy X-ray absorptiometry and magnetic resonance imaging spectroscopy.

RESULTS

The change in cardiorespiratory fitness with training was independently associated with reductions in BMI z-score (β = -0.09; P = 0.006), total fat mass (β = -1.40; P = 0.007), trunk fat mass (β = -0.70; P = 0.01), and liver fat (β = -1.80; P = 0.053). Adolescents within the highest tertile of change in fitness were 4.67 (95% CI: 1.15-13.73; P = 0.03), 11.90 (95% CI: 2.37-59.77; P = 0.002), and 6.21 (95% CI: 1.14-33.99; P = 0.035) times more likely to experience decreases in body weight, BMI, and liver fat compared with adolescents in the lowest tertile.

CONCLUSIONS

The changes in adiposity and hepatic triglyceride content in response to endurance training are significantly related to the increase in cardiorespiratory fitness in adolescents at risk of T2DM.

[Measurements of location of body fat distribution: an assessment of colinearity with body mass, adiposity and stature in female adolescents]

OBJECTIVE

: To verify the correlation between body fat location measurements with the body mass index (BMI), body fat percentage (BF%) and height, according to the nutritional status in female adolescents.

METHODS

: A controlled cross-sectional study was carried out with 113 adolescents (G1: 38 with normal weight, but with high body fat level, G2: 40 with normal weight and G3: 35 overweight) from public schools in Viçosa-MG, Brazil. The following measures were assessed: weight, height, waist circumference (WC), umbilical circumference (UC), hip circumference (HC), thigh circumference, waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), waist-to-thigh ratio (WTR), conicity index (CI), sagittal abdominal diameter (SAD), coronal diameter (CD), central (CS) and peripheral skinfolds (PS). The BF% was assessed by tetrapolar electric bioimpedance.

RESULTS

: The increase in central fat, represented by WC, UC, WHtR, SAD, CD and CS, and the increase in peripheral fat indicated by HC and thigh circumference were proportional to the increase in BMI and BF%. WC and especially the UC showed the strongest correlations with adiposity. Weak correlation between WHR, WTR, CI and CS/PS with adiposity were observed. The height showed correlation with almost all the fat location measures, being fair or weak with waist measurements.

CONCLUSIONS

: The results indicate colinearity between body mass and total adiposity with central and peripheral adipose tissue. We recommend the use of UC for assessing nutritional status of adolescents, as it showed the highest capacity to predict adiposity in each group, and also showed fair or weak correlation with height.

Association between obesity and high blood pressure among Lithuanian adolescents: a cross-sectional study

BACKGROUND

Most epidemiological studies have shown that the prevalence of high blood pressure (BP) has significantly increased among children and adolescents in various countries of the world. The aim of this study was to examine the associations between overweight, obesity, abdominal obesity and prehypertension and hypertension among Lithuanian adolescents aged 12-15 years.

METHODS

The subjects with increased BP (≥90th percentile) were screened on two separate occasions. Data on the body mass index (BMI), waist circumference (WC), and BP were analysed in 7,457 adolescents aged 12-15 years. Adjusted odds ratios (aORs) with 95% confidence intervals (CI) for the associations were estimated using multivariate logistic regression models.

RESULTS

After two screenings, the study participants were categorised as prehypertensive (12.8%), hypertensive (22.2%), and normotensive (65%). The overall prevalence of overweight, obesity, and abdominal obesity (if WC was in the ≥75th percentile) were 12.1%, 2.4%, and 9%, respectively. After adjusting for age and sex, significant associations were found between overweight and obesity and high BP, namely, prehypertension (overweight: aOR = 2.62; 95% CI 2.13-3.23; obesity: aOR = 4.81; 95% CI 3.08-7.52) and hypertension (overweight: aOR = 3.56; 95% CI 3.02-4.19; obesity: aOR = 6.64; 95% CI 4.65-9.49). Prehypertension was found to be significantly associated with WC in the 75th- < 90th percentiles (aOR = 3.16; 95% CI 2.43-4.10) and WC in the ≥90th percentile (aOR = 4.08; 95% CI 2.35-7.10). For hypertension, significant associations were detected with WC in the 75th- < 90th percentiles (aOR = 3.92; 95% CI 3.18-4.82) and WC in the ≥90th percentile (aOR = 7.41; 95% CI 4.97-11.05).

CONCLUSIONS

Overweight, obesity, and abdominal obesity were associated with prehypertension and hypertension.

Endocrine check-up in adolescents and indications for referral: A guide for health care providers

The American Academy of Pediatrics recommends that young people between the ages of 11 and 21 years should be seen annually by their pediatricians, since annual checkups can be an important opportunity for health evaluation and anticipatory guidance. Parents of infants and young children are accustomed to regularly visiting a pediatrician for their child's checkups. Unfortunately, when children reach the teen years, these annual checkups may decrease in frequency. In routine check-ups and medical office visits, particular attention should be paid to the possibility of a developmental or endocrine disorder. Early diagnosis and treatment may prevent medical complications in adulthood and foster age-appropriate development. Our purpose is to acquaint readers with the concept, based on current scientific understanding, that some endocrine disorders may be associated with a wide range of deleterious health consequences including an increased risk of hypertension and hyperlipidemia, increased risk of coronary artery disease, type 2 diabetes, significant anxiety and lack of self-esteem. Understanding the milestones and developmental stages of adolescence is essential for pediatricians and all other health providers who care for adolescents. Treating adolescents involves knowledge of a variety of medical, social and legal information; in addition, close working relationships must be established within the adolescent's network to create an effective care system. In summary, we underline the importance of a periodic endocrine checkup in adolescents in order to identify endocrine problems early and develop an approach to treatment for those patients who need help during this time. Indications for endocrine referral for professional and other healthcare providers are also included. These lists are clearly not intended to be comprehensive, but will hopefully serve as a guide for specific clinical circumstances.

Age and sex-specific relationships between phthalate exposures and obesity in Chinese children at puberty

OBJECTIVE

To examine the age and sex-specific associations of urine levels of six mono-phthalates with body size and fat distribution in Chinese children at puberty.

MATERIALS AND METHODS

Four hundred and ninety-three school-aged children (247 boys, 246 girls) were recruited. Obesity related anthropometric indices were measured and body fat proportion (BF%) was calculated. Spot urine samples were collected and phthalate monoesters were detected by an API 2000 electrospray triple quadrupole mass spectrometer (ESI-MS/MS). Associations between phthalate exposure and overweight/obesity measures and their trends were examined by multiple linear regression and Logistic regression analyses, respectively.

RESULTS

Di-2-ethylhexyl phthalate (DEHP) metabolites and monobutyl phthalate (MBP) were found to be the most detectable chemicals. In 8-10 years (yrs) group, concentrations of MEHP and MBP were significantly higher in girls than those in boys. However, concentrations of all phthalate monoesters, except for MEP and MEHP, in 11-13 yrs boys were significantly higher than those in girls. After adjusting for confounders including puberty onset, urinary concentrations of MBP and sum of low molecular-weight phthalate metabolites (∑LMP) were positively associated with boys' obesity in a concentration-effect manner, while concentrations of MEHP, MEHHP and sum of DEHP metabolites (∑MEHP) were negatively associated with girls' obesity. Associations between phthalate exposure levels and BMI z-score changes were age- and sex-specific in school-age children.

CONCLUSION

There are age and sex-specific concentration-effect associations between phthalate exposure and fat distribution in Chinese children. Urinary phthalate levels in 11-13 yrs boys were about 30 percent higher than those in girls, and ∑MEHP levels in younger boys (<10 yrs) were significantly higher than those in elder boys (>10 yrs). Associations were positive for MBP and ∑LMP with both BMI z-score and fat distribution in boys >10 years of age, and negative for ∑MEHP with fat distribution in girls <10 years of age.

Anthropometric measures of abdominal adiposity for the identification of cardiometabolic risk factors in adolescents

Sagittal abdominal diameter (SAD) was obtained in 65 adolescents referred for assessment of cardiometabolic risk. We found that SAD was associated with cardiometabolic risk factors independent of BMI in males, but that SAD was not superior to BMI or other measures of abdominal adiposity for the detection of metabolic syndrome.

A five year longitudinal study investigating the prevalence of childhood obesity: comparison of BMI and waist circumference

OBJECTIVE

The purpose of this study was to examine the prevalence of obesity over time in the same individuals comparing body mass index (BMI), waist circumference (WC) and waist to height ratio (WHtR).

STUDY DESIGN

Five year longitudinal repeated measures study (2005-2010). Children were aged 11-12 (Y7) years at baseline and measurements were repeated at age 13-14 (Y9) years and 15-16 (Y11) years.

METHODS

WC and BMI measurements were carried out by the same person over the five years and raw values were expressed as standard deviation scores (sBMI and sWC) against the growth reference used for British children.

RESULTS

Mean sWC measurements were higher than mean sBMI measurements for both sexes and at all assessment occasions and sWC measurements were consistently high in girls compared to boys. Y7 sWC = 0.792 [95% confidence interval (CI) 0.675-0.908], Y9 sWC = 0.818 (95%CI 0.709-0.928), Y11 sWC = 0.943 (95%CI 0.827-1.06) for boys; Y7 sWC = 0.843 (0.697-0.989), Y9 sWC = 1.52 (95%CI 1.38-0.67), Y11 sWC = 1.89 (95%CI 1.79-2.04) for girls. Y7 sBMI = 0.445 (95%CI 0.315-0.575), Y9 sBMI = 0.314 (95%CI 0.189-0.438), Y11 sBMI = 0.196 (95%CI 0.054-0.337) for boys; Y7 sBMI = 0.353 (0.227-0.479), Y9 sBMI = 0.343 (95%CI 0.208-0.478), Y11 sBMI = 0.256 (95%CI 0.102-0.409) for girls. The estimated prevalence of obesity defined by BMI decreased in boys (18%, 12% and 10% in Y 7, 9 and 11 respectively) and girls (14%, 15% and 11% in Y 7, 9 and 11). In contrast, the prevalence estimated by WC increased sharply (boys; 13%, 19% and 23%; girls, 20%, 46% and 60%).

CONCLUSION

Central adiposity, measured by WC is increasing alongside a stabilization in BMI. Children appear to be getting fatter and the additional adiposity is being stored centrally which is not detected by BMI. These substantial increases in WC are a serious concern, especially in girls.

Liver fat has a stronger association with risk factors for type 2 diabetes in African-American compared with Hispanic adolescents

CONTEXT

Although overweight and obese African-Americans (AAs) have less visceral adipose tissue (VAT) and liver fat (LF) than Hispanics, they have a similar risk for type 2 diabetes.

OBJECTIVE

We examined ethnic differences in the association between VAT and LF with risk factors for type 2 diabetes to help explain this paradox.

DESIGN

We conducted a cross-sectional study in an academic pediatric care facility.

SUBJECTS

Subjects were overweight and obese AA (n = 131; 15.5 ± 3.3 years old) and Hispanic adolescents (n = 227; 14.7 ± 3.0 years old).

MAIN OUTCOME MEASURES

Outcome measures included insulin sensitivity (SI), acute insulin response (AIR), and disposition index (DI) by frequently sampled i.v. glucose tolerance test and minimal modeling.

RESULTS

LF, not VAT, was inversely associated with SI, and the effect of high LF compared with low was more pronounced in AAs (P(interaction) < .05). In Hispanics, high LF was associated with a 24% lower SI (P < .01) and a 31% increase in AIR (P < .01) and was not associated with DI (P = .35). In AAs, high LF was associated with a 49% lower SI (P < .001), was not associated with an increase in AIR (P = .25), and was associated with a 42% lower DI (P < .01), indicating failure of compensatory insulin secretion/clearance in response to insulin resistance. Prediabetes changed the relationship between high/low LF and DI in Hispanics (P(interaction) = .002) but not AAs such that prediabetic Hispanics with high LF had a 43% lower DI (P = .03) with no difference in those without prediabetes (P = .06).

CONCLUSIONS

LF has a stronger effect on SI compared with VAT. Our results suggest that the impact of high LF on poor β-cell compensation is more pronounced in AAs. In Hispanics, the combination of high LF and prediabetes contributes to poor β-cell compensation.

Calculating cardiac risk in obese adolescents before and after onset of lifestyle intervention

Prevalence and severity of obesity in adolescents is increasing worldwide. The obesity-associated cardiovascular risk factors (CRF) determine cardiac risk as demonstrated by longitudinal studies. Fat distribution and not overall fat mass determines the cardiac risk, since intra-abdominal adipose tissue is especially related to CRFs. Besides classical CRFs such as hypertension, dyslipidemia and impaired glucose metabolism, a proinflammatory and prothrombotic state in obesity is associated with cardiac risk. Adipocytokines such as adiponectin are related to cardiac risk and may present useful predictors of cardiac mortalities in future. Measurement of the carotid intima-media thickness is a new promising noninvasive marker for early cardiovascular changes including atherosclerosis. The therapy of choice to prevent cardiac events in obesity is lifestyle intervention of obese adolescents. However, in clinical practice, the weight loss in lifestyle interventions is only moderate and drug treatment of CRFs is seldom performed.

Optimal waist-to-height ratio values for cardiometabolic risk screening in an ethnically diverse sample of South African urban and rural school boys and girls

Background

The proposed waist-to-height ratio (WHtR) cut-off of 0.5 is less optimal for cardiometabolic risk screening in children in many settings. The purpose of this study was to determine the optimal WHtR for children from South Africa, and investigate variations by gender, ethnicity and residence in the achieved value.

Methods

Metabolic syndrome (MetS) components were measured in 1272 randomly selected learners, aged 10–16 years, comprising of 446 black Africans, 696 mixed-ancestry and 130 Caucasians. The Youden’s index and the closest-top-left (CTL) point approaches were used to derive WHtR cut-offs for diagnosing any two MetS components, excluding the waist circumference.

Results

The two approaches yielded similar cut-off in girls, 0.465 (sensitivity 50.0, specificity 69.5), but two different values in boys, 0.455 (42.9, 88.4) and 0.425 (60.3, 67.7) based on the Youden’s index and the CTL point, respectively. Furthermore, WHtR cut-off values derived differed substantially amongst the regions and ethnic groups investigated, whereby the highest cut-off was observed in semi-rural and white children, respectively, Youden’s index0.505 (31.6, 87.1) and CTL point 0.475 (44.4, 75.9).

Conclusion

The WHtR cut-off of 0.5 is less accurate for screening cardiovascular risk in South African children. The optimal value in this setting is likely gender and ethnicity-specific and sensitive to urbanization.

[Estimated glucose disposal rate in patients under 18 years of age with type 1 diabetes mellitus and overweight or obesity]

OBJECTIVE

To assess the estimated glucose disposal rate (eGDR), insulin dose, and lipoprotein profile in children with type 1 diabetes mellitus (T1DM) and overweight or obesity as compared to children with T1DM and normal weight.

METHODS

A total of 115 patients (aged 5-16 years) with T1DM on intensive insulin therapy were recruited. The following parameters were measured: weight, height, body mass index, waist and hip circumference, insulin dose, eGDR, glycosylated hemoglobin, blood pressure, and lipoprotein profile. Results were stratified by sex and age.

RESULTS

No significant differences were found in eGDR between children with normal weight, overweight, and obesity. However, obese children older than 11 years had lower eGDR values (9.3±1.3 vs 10.1±0.8 mg kg(-1)min(-1); p<0.01). Insulin dose was higher in overweight and obese children, especially in IU/m2/day (37.7 vs 36.1 vs. 29.4 respectively; p<0.01). Obese children had higher low-density lipoprotein cholesterol levels than children with overweight and normal weight (106.5 vs 91.7 vs 91.5mg/dL respectively; p<0.01). No correlation was found between waist circumference and the different markers of insulin resistance.

CONCLUSIONS

Values of eGDR values were lower in obese children with T1DM older than 11 years, and this may therefore be considered a marker of insulin resistance. Insulin dose was higher in diabetic patients with overweight or obesity, specially in IU/m2/day. Obese children with T1DM had a lipoprotein profile of cardiovascular risk.

Physical activity intensity, sedentary time, and body composition in preschoolers

BACKGROUND

Detailed associations between physical activity (PA) subcomponents, sedentary time, and body composition in preschoolers remain unclear.

OBJECTIVE

We examined the magnitude of associations between objectively measured PA subcomponents and sedentary time with body composition in 4-y-old children.

DESIGN

We conducted a cross-sectional study in 398 preschool children recruited from the Southampton Women's Survey. PA was measured by using accelerometry, and body composition was measured by using dual-energy X-ray absorptiometry. Associations between light physical activity, moderate physical activity (MPA), vigorous physical activity (VPA), and moderate-to-vigorous physical activity (MVPA) intensity; sedentary time; and body composition were analyzed by using repeated-measures linear regression with adjustment for age, sex, birth weight, maternal education, maternal BMI, smoking during pregnancy, and sleep duration. Sedentary time and PA were also mutually adjusted for one another to determine whether they were independently related to adiposity.

RESULTS

VPA was the only intensity of PA to exhibit strong inverse associations with both total adiposity [P < 0.001 for percentage of body fat and fat mass index (FMI)] and abdominal adiposity (P = 0.002 for trunk FMI). MVPA was inversely associated with total adiposity (P = 0.018 for percentage of body fat; P = 0.022 for FMI) but only because of the contribution of VPA, because MPA was unrelated to fatness (P ≥ 0.077). No associations were shown between the time spent sedentary and body composition (P ≥ 0.11).

CONCLUSIONS

In preschoolers, the time spent in VPA is strongly and independently associated with lower adiposity. In contrast, the time spent sedentary and in low-to-moderate-intensity PA was unrelated to adiposity. These results indicate that efforts to challenge pediatric obesity may benefit from prioritizing VPA.

The hypertriglyceridemic waist, waist-to-height ratio, and cardiometabolic risk

OBJECTIVE

To investigate whether the hypertriglyceridemic waist (HW) phenotype and waist-to-height ratio (WHTR) are associated with cardiometabolic disorders in children and adolescents.

STUDY DESIGN

This was a cross-sectional design study. Anthropometry, biochemical variables, and cardiorespiratory fitness were assessed in 234 participants (122 girls) aged 10-19 years from Bedfordshire, United Kingdom. The HW phenotype was defined as a waist circumference ≥90(th) percentile for age and sex, and triglyceride concentrations ≥1.24 mmol/L, and a high WHTR defined as >0.5. ANCOVA and logistic regression were used in the analysis.

RESULT

In participants with the HW phenotype, the odds of having high cardiorespiratory fitness (mL/kg/min) were lower (0.045; 95% CI 0.01, 0.42), and the odds of having low high-density lipoprotein cholesterol (4.41; 1.50, 12.91), impaired fasting glucose (3.37; 1.06, 10.72), and ≥1 (4.78; 1.32, 17.29) and ≥2 risk factors (7.16; 2.38, 21.54) were higher than those without the phenotype. Those with a high WHTR had higher odds of having low high-density lipoprotein cholesterol (2.57; 1.11, 5.95), high diastolic blood pressure (3.21; 1.25, 8.25), and ≥2 risk factors (5.57; 2.05, 15.17) than those with normal WHTR.

CONCLUSION

The HW phenotype may be a better simple marker than WHTR for identifying children and adolescents at risk for cardiometabolic disorders.