Waist circumference and waist-to-height ratio are better predictors of cardiovascular disease risk factors in children than body mass index

Waist circumference, waist-to-height ratio and conicity index to evaluate android fat excess in Brazilian children

OBJECTIVE

To evaluate the ability of anthropometric measurements to identify excess android fat and to propose cut-off points for excess central adiposity in children, according to age and sex.

DESIGN

A cross-sectional study with children from a municipality of Minas Gerais, Brazil. Receiver-operating characteristic curve analyses were performed to evaluate waist circumference (WC), waist-to-height ratio (WHtR) and conicity index (C-index) in estimating excess android fat by dual energy X-ray absorptiometry (DXA).

SETTING

Viçosa, Minas Gerais, Brazil.

SUBJECTS

Children aged 4-9 years (n 788).

RESULTS

Overweight prevalence was 29·1 % and android fat percentage was higher among girls. All central fat measurements were able to discriminate excess android fat in the age groups evaluated, especially WC and WHtR, with cut-off points showing good sensitivity and specificity overall.

CONCLUSIONS

Because these methods are easy to obtain and inexpensive, it is possible to use WC, WHtR and C-index in population surveys to evaluate central obesity. The proposed cut-off points showed satisfactory values of sensitivity and specificity and can be used in epidemiological studies.

Food intake and high-sensitivity C-reactive protein levels in adolescents

BACKGROUND AND AIMS

Diet comprises factors with anti and pro-inflammatory potential that can contribute to modulate obesity-induced inflammation. We aimed to assess the association between food intake and high-sensitivity C-reactive protein (hsCRP) levels in adolescents.

METHODS AND RESULTS

A cross-sectional analysis of 991 adolescents aged 13 years old was conducted as part of the EPITeen cohort, Porto, Portugal. Food intake was assessed by a food frequency questionnaire and thirteen food groups were defined. Anthropometric assessment was performed and serum hsCRP was measured in a fasting blood sample. hsCRP concentrations above the 75th percentile were considered high. Logistic regression was fitted to estimate the association between the intake frequency of the food groups and hsCRP, stratified by BMI and adjusted for sex, parental education and total energy intake. Median (25-75th percentiles) hsCRP concentrations increased with increasing values of BMI [normal weight: 0.20 (0.10-0.50); overweight: 0.40 (0.20-0.80); obese: 1.10 (0.40-2.15) mg/l, p < 0.001]. After adjustment for sex, parental education and total energy intake, no statistically significant associations were found amongst normal weight and overweight participants. However, among obese individuals, having as reference the first frequency category (<1 per day), a higher frequency of vegetables/legumes intake showed a decreased odds of high hsCRP levels (OR: 0.10, 95%CI 0.03-0.38, 1-3 per day; and OR: 0.14, 95%CI 0.04-0.52, >3 per day).

CONCLUSION

Among participants with obesity-induced higher hsCRP levels, a higher frequency of vegetable/legume intake was inversely related to hsCRP.

Correlates of elevated blood pressure in healthy children: a systematic review

The prevalence of hypertension in children is increasing globally. Addressing this will require a robust understanding of associated risk factors. To this end, we conducted a systematic review to identify correlates of elevated blood pressure (BP) in children. Literature searches were conducted using pre-defined search terms from three academic databases. The abstract and full text of identified studies were screened for eligibility by two independent reviewers. A total of 100 studies were included in this systematic review. An assessment tool was first used to assess study quality; a narrative synthesis was then performed. We found a broad range of physiological, social and behavioural factors associated with elevated BP in children. The most common correlate observed was adiposity, suggesting that childhood obesity may be implicated in the increased prevalence of hypertension observed in children. However, the broad range of other factors identified underscores the multi-factorial aetiology of hypertension. Data from a broad range of studies showed that the correlates of hypertension in children are multi-factorial. Therefore, approaches aimed at preventing hypertension must in turn be multi-factorial to ensure that the burden of hypertension in childhood is addressed.

Waist circumference percentile curves as a screening tool to predict cardiovascular risk factors and metabolic syndrome risk in Brazilian children

The goals of this study were to develop reference values for waist circumference (WC) in Brazilian children between 6-10 years old and to evaluate the WC performance in predicting cardiovascular risk factors and metabolic syndrome (MetS) in children. This is a population-based epidemiological cross-sectional study, in which 1,397 children participated, with a 6-10 years old probability sampling and from public and private schools in the city of Uberaba, Minas Gerais State, Brazil. WC was measured at the waist narrowest point (WC1) and at the umbilicus level (WC2). Blood samples and blood pressure were collected to determine the MetS diagnosis. There was a significant effect of age (p = 0.001), anatomical point (WC1 vs. WC2, p = 0.001) and sex-anatomical point interaction (p = 0.016) for WC. Smoothed sex- and age-specific 5th, 10th, 25th, 50th, 75th, 90th and 95th percentile curves of WC1 and WC2 were designed by the LMS method. WC was accurate to predict MetS, for all ages [area under the ROC curve (AUC) > 0.79 and p < 0.05], regardless of sex. This study presented percentile curves for WC at two anatomical points in a representative sample of Brazilian children. Furthermore, WC was shown to be a strong predictor of cardiovascular risk factors and MetS in children.

Waist-to-height ratio, body mass index, and cardiovascular risk profile in children with chronic kidney disease

BACKGROUND

Cardiovascular (CV) risk is high in children with chronic kidney disease (CKD), and further compounded in those who are overweight. Children with CKD have a unique body habitus not accurately assessed by body mass index (BMI). Waist-to-height ratio (WHr), a better predictor of CV risk in populations with short stature, has not been investigated in children with CKD.

METHODS

Analysis of 1723 visits of 593 participants enrolled in the Chronic Kidney Disease in Children (CKiD) study was conducted. CKiD participants had BMI and WHr measured and classified as follows: (1) lean (WHr ≤ 0.49, BMI < 85th percentile); (2) WHr-overweight (WHr > 0.49, BMI < 85th percentile); (3) BMI-overweight (WHr ≤ 0.49, BMI ≥ 85th percentile); or (4) overweight by both BMI and WHr. Left ventricular mass index (LVMI), fasting lipids, fibroblast growth factor 23 (FGF23), blood pressure, and glucose were measured as markers of CV risk. Linear mixed-effects regression was used to evaluate differences in CV markers between overweight and lean groups.

RESULTS

Participants were 12.2 years old, 60% male, and 17% African-American. Approximately 15% were overweight by WHr but not by BMI. Overweight status by WHr-only or both WHr and BMI was associated with lower high-density lipoprotein (HDL) and higher LVMI, triglycerides, and non-HDL cholesterol compared to lean. CV markers of participants overweight by BMI-only were similar to those of lean children.

CONCLUSIONS

WHr-adiposity is associated with an adverse CV risk profile in children with CKD. A significant proportion of children with central adiposity are missed by BMI. WHr should be utilized as a screening tool for CV risk in this population.

Waist-to-height ratio remains an accurate and practical way of identifying cardiometabolic risks in children and adolescents

AIM

We evaluated how effectively the waist-to-height ratio (WHtR) identified cardiometabolic risk (CMR) in children and adolescents, compared with the tri-ponderal mass index, percentage of body fat and other obesity indexes.

METHODS

Eligible subjects were recruited from three metropolitan regions of China from May 2013 to June 2014. Subjects with at least three of the following abnormalities - hypertension, dyslipidemia, elevated fasting blood glucose and central obesity - were defined as CMR1 and children with at least two were defined as CMR2. The area under the curve (AUC) of the receiver operating characteristic curve was used to compare how effectively obesity indexes predicted CMR.

RESULTS

We recruited 3556 subjects aged 7-18 years. All five obesity indexes showed good, comparable performances in identifying CMR and the AUCs ranged from 0.89 to 0.90 for CMR1 and 0.83 to 0.85 for CMR2. The cut-off of 0.467 for WHtR achieved a sensitivity of 0.91 and specificity of 0.80 for predicting CMR1, with the best cut-offs being 0.463 for boys and 0.469 for girls.

CONCLUSION

The WHtR was a superior and practical screening tool for detecting CMR in this paediatric population, as it provided comparable accuracy to other methods and just required a simple calculation.

Association of anthropometric measures and cardio-metabolic risk factors in normal-weight children and adolescents: the CASPIAN-V study

BACKGROUND

The present study aims to explore the association of anthropometric indices and cardio-metabolic risk factors in normal-weight children and adolescents.

METHODS

This cross-sectional nationwide study was conducted in 2015 among 4200 Iranian school students aged 7-18 years. They were selected using a multi-stage cluster random sampling method. Anthropometric indices and cardio-metabolic risk factors including fasting blood glucose (FBG), lipid profile and blood pressure (BP) were measured using standard protocols.

RESULTS

The response rate was 91.5%. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) had a significant positive correlation with waist circumference (WC), hip circumference (HC) and body mass index (BMI) in boys and girls. HDL-C had a significant inverse correlation with WC, HC and BMI in boys. For each unit increase in WC, HC and BMI, the risk of elevated DBP significantly increased by 2%, 1% and 11%, respectively. Likewise, for each unit increase in WC, HC and BMI, the risk of elevated BP significantly raised by 2%, 1% and 10%, respectively. For each unit increase in WC, the risk of metabolic syndrome increased by 7%.

CONCLUSIONS

Anthropometric indices are considered an easy, non-invasive tool for the prediction of cardio-metabolic risk factors in normal-weight children and adolescents.

Using Anthropometric Indicator to Identify Hypertension in Adolescents: A Study in Sarawak, Malaysia

This cross-sectional study was conducted to determine the predictive power of anthropometric indicators and recommend cutoff points to discriminate hypertension among adolescents in Sarawak, Malaysia. A total of 2461 respondents aged 12-17 years participated in this study with mean age of 14.5±1.50 years. All anthropometric indicators had significant area under the ROC curve, with body mass index (BMI) and waist circumference (WC) ranging from 0.7 to 0.8. The best anthropometric indicators for predicting hypertension for boys were WC, BMI, and waist-to-height ratio (WHtR). For girls, BMI was the best indicators followed by WHtR and WC. The recommended BMI cutoff point for boys was 20 kg/m² and 20.7 kg/m² for girls. For WC, the recommended cutoff point was 67.1 cm for boys and 68.2 cm for girls. BMI and WC indicators were recommended to be used at the school setting where the measurement can easily be conducted.

Chest width, waist circumference, and thigh circumference are predictors of dementia

OBJECTIVE

Few studies have investigated the relationship between specific body measures and dementia.

METHODS

Three-dimensional anthropometric body surface scanning data containing 38 body measures were collected from 6831 participants from the health examination department of a medical center in Taiwan during 2000 to 2008, and 236 dementia cases were identified during the 10-year follow-up. A multiple Cox regression analysis was performed.

RESULTS

Specific body measures, namely chest width (hazard ratio [HR] = 0.90; 95% confidence interval [CI] = 0.83-0.98), and right thigh circumference (HR = 0.93; 95% CI = 0.90-0.96), were protective predictors to dementia occurrence. Waist circumference (HR = 1.03; 95% CI = 1.02-1.05) was a risk factor in dementia occurrence. Among the combinations, dementia risk was higher in participants with a larger waist circumference and a smaller right thigh circumference, with the highest HR of 2.49 (95% CI = 1.54-4.03).

CONCLUSION

The body measures provide clues for future applications and scientific merits in both clinical and preventive medicine.

The association of neck circumference with risk of metabolic syndrome and its components in adults: A systematic review and meta-analysis

BACKGROUND & AIMS

Several prior studies suggested that neck circumference (NC) is a reliable diagnostic tool for risk of metabolic syndrome (MetS) and its features. However, not all studies support this view. Therefore, we aimed to perform a meta-analysis to summarize the association between NC with MetS and its components in adult populations.

METHODS AND RESULTS

PubMed/Medline, Web of Knowledge, and Scopus electronic databases were searched until May 31, 2017 to find relevant English-language papers. We included studies that examined the association of NC with risk of MetS, or at minimum, one of its components as outcomes. Of 2628 publications identified, 19 papers met selection criteria. We found no association between NC and MetS (odd ratio (OR): 0.73; 95% CI: 0.003, 1.47). However, there was a positive association between NC and waist circumference (WC) (r = 0.85; 95%: 0.75, 0.95; I²: 98.2%; p = 0.0001), BMI: (r:0.88; 95% CI: 0.74, 0.91, I²:97.3%), triglycerides (TG) (OR: 1.87; 95% CI: 1.60, 2.19; I²:58.4%; p = 0.03), TC (r:0.14; 95%CI: 0.05, 0.23, I²:94.1%), LDL-C (r: 0.18; 95%CI: 0.07, 0.29, I²:94.3%), hypertension (OR: 1.94; 95% CI:1.43, 2.64, I²:87.3%), systolic (r: 0.21, 95%CI: 0.19, 0.23; I²:67.1%) and diastolic blood pressures (r: 0.20, 95%CI: 0.16, 0.23; I²:79.7%), low HDL-C (r:-0.21; 95% CI: -0.26, -0.15, I² = 92.5%), as well as fasting blood sugar (FBS) concentrations (r: 0.20, 95%CI: 0.16, 0.24; I²:88.1%).

CONCLUSION

Subjects with higher NC were at approximately two-fold higher risk for hypertriglyceridemia compared to those with lower NC. We found positive associations between NC, WC, BMI, hypertension, FBS, TC, LDL-C, SBP, DBP, and low HDL-C concentrations. However, heterogeneity was considerably high. Therefore, the findings should be taken with caution. Future studies using longitudinal designs are needed to further understand the association between NC and features of MetS.

Dyslipidemia and Fatty Liver Disease in Overweight and Obese Children

Introduction

Obesity is a worldwide concern. It is associated with morbidity such as dyslipidemia and liver disease. Childhood obesity has dramatically increased, particularly in the Gulf region. We aim to assess the prevalence of dyslipidemia and fatty liver disease (FLD) in overweight and obese children and analyze the association between different anthropometric measures with dyslipidemia and fatty liver disease.

Methods

A descriptive, cross-sectional study conducted on children referred with obesity. BMI percentiles were plotted and standardized waist circumference (WC) was generated. Family history of metabolic syndrome was recorded. Fasting lipid, liver transaminases, and ultrasound scans (US) for those with elevated enzymes were performed. Descriptive statistics were used for quantitative parameters.

Results

216 participants were recruited. Mean ± SD age was 10.58 ± 2.996 years. 55.3% had dyslipidemia; 11.7% had high cholesterol, 28.6% high triglyceride, 32.7% high LDL, and 18.0% low HDL. 51 (84%) had either elevated transaminases. All had liver US, and 43 had FLD. WC was strongly associated with dyslipidemia and FLD (P=0.04  and  0.003).

Conclusion

Dyslipidemia is common in overweight, obese children. FLD is prevalent in those with elevated liver transaminases. WC is an easy tool that can be utilized to screen for dyslipidemia and FLD in overweight and obese children.

Anthropometric features as predictors of atherogenic dyslipidemia and cardiovascular risk in a large population of school-aged children

BACKGROUND

Autopsy studies reveal that atherosclerosis lesions can be found as early as two years of age. To slow the development of this early pathology, obesity and dyslipidemia prevention should start from childhood making it urgent to explore new ways to evaluate dyslipidemia risk in children that can be applied widely, such as the non-invasive anthropometric evaluation.

OBJECTIVE

Assess the metabolic profile of a pediatric population at a specific age to describe the association between anthropometric and biochemical cardiovascular disease risk factors; and evaluate selected anthropometric variables as potential predictors for dyslipidemic cardiovascular risk.

DESIGN AND METHODS

Anthropometric features, bioimpedance parameters and fasting clinical profile were assessed in Lisbon and the Tagus Valley region pre-pubertal nine-year-old children (n = 1.496) from 2009-2013 in a descriptive, cross-sectional study. Anthropometric variables predictive power was evaluated through regression analysis.

RESULTS

At least one abnormal lipid parameter was found in 65% of "normal weight", 73% of "overweight" and 81% of "obese" children according to the International Obesity Task Force (IOTF) standards. Dyslipidemia was present in 67.8% of children. Waist-hip ratio (WHR) explained 0.4% of total cholesterol (TC) variance. Waist circumference (WC) explained 2.8% of apolipoprotein (APO) A1 variance. Waist-circumference-to-height-ratio (WHtR) explained 2.7%, 2.8% and 1.9% of low-density lipoprotein cholesterol (LDL-c), APO B, and N_HDL-c variance, respectively. Children with abnormally high WHR levels had an increase in risk of 4.49, 3.40 and 5.30 times, respectively, for developing cardiovascular disease risk factors measured as high-risk levels of TC, LDL-c and non-HDL-c (N_HDL-c) (p<0.05). Only 29.9% of "normal weight" children had no anthropometric, bioimpedance or biochemical parameters associated with CV risk.

CONCLUSION

A large proportion of school age children have at least one lipid profile abnormality. BMI, zBMI, calf circumference (CC), hip circumference (HC), WC, and WHR are directly associated with dyslipidemia, whereas HC and calf circumference (CC) adjusted to WC, and mid-upper arm circumference (MUAC), are all inversely associated with dyslipidemia. Selected anthropometric variables are likely to help predict increased odds of having CV risk factors.

Building healthy communities: A comprehensive school health program to prevent obesity in elementary schools

Obesity among children is highly prevalent and can lead to risk factors for chronic disease in adulthood. Key organizations have called on schools to play a larger role by increasing children's physical activity and nutrition by adopting an overall culture of health. This study examined the impact of a socioecological theory driven school-wide nutrition and physical activity intervention on 5th graders' central adiposity and obesity level. In 2015-2016, in the Midwest region of U.S., four treatment and two control schools, including 628 (377 treatment) 5th grade children participated in an eight-month intervention. Children in the treatment schools participated in a comprehensive healthy school transformation program consisting of six components. Waist-to-Height Ratio (WHtR) and Body Mass Index (BMI) was calculated and used as the measure of obesity. ANCOVA revealed a significant difference in WHtR among treatment and control groups at time two (T2) F_MI(1,6148.14) = 4.43, p = .035, R² = 0.64, R²_Treament = 0.01, with no significant differences based on age, sex, and race. Additionally, the ANCOVA for BMI revealed a marginally significant lower BMI among the treatment than comparison group students F_MI(1, 614) = 3.575, p = .059, R² = 0.01 (M_diff = -0.23, 95%CI upper boundary: -0.03). The healthy school intervention led to significant differences in obesity levels, regardless of age, sex, or race, across the 8-month program between 5th grade children in treatment and non-treatment schools. This supports the ability of schoolwide programs to significantly and positively impact student health and chronic disease prevention.

Anthropometric measures as fitness indicators in primary school children: The Health Oriented Pedagogical Project (HOPP)

Aims: As children’s fitness continues to decline, frequent and systematic monitoring of fitness is important. Easy-to-use and low-cost methods with acceptable accuracy are essential in screening situations. This study aimed to investigate how the measurements of body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WHtR) relate to selected measurements of fitness in children. Methods: A total of 1731 children from grades 1 to 6 were selected who had a complete set of height, body mass, running performance, handgrip strength and muscle mass measurements. A composite fitness score was established from the sum of sex- and age-specific z-scores for the variables running performance, handgrip strength and muscle mass. This fitness z-score was compared to z-scores and quartiles of BMI, WC and WHtR using analysis of variance, linear regression and receiver operator characteristic analysis. Results: The regression analysis showed that z-scores for BMI, WC and WHtR all were linearly related to the composite fitness score, with WHtR having the highest R2 at 0.80. The correct classification of fit and unfit was relatively high for all three measurements. WHtR had the best prediction of fitness of the three with an area under the curve of 0.92 ( p < 0.001). Conclusions: BMI, WC and WHtR were all found to be feasible measurements, but WHtR had a higher precision in its classification into fit and unfit in this population.

Comparison of Hypertension Prediction Analysis Using Waist Measurement and Body Mass Index by Age Group

Objectives

The purpose of this study was to evaluate hypertension with simple anthropometry data related to obesity in Korean adults and identify whether age specific waist circumference (WC) may be a useful screening tool for determining hypertension.

Methods

Subjects (n = 571) were classified into 3 groups by age; young (18-39 years), middle aged (40-64 years), and old aged (≥ 65 years). Correlations between demographic and anthropometric parameters and hypertension were performed using Spearman correlation analysis. Logistic regression analysis and ROC (receiver operating characteristics) curves were also analyzed for correlations with hypertension.

Results

Spearman correlation analyses, age, gender, WC, and body mass index were positively correlated with hypertension. When logistic regression analysis was performed, increased age and increased WC was associated with a higher incidence of hypertension, although gender and body mass index were not significantly related to hypertension. In ROC analysis of WC for hypertension demonstrated that patients in the old age group showed higher WC cutoff value than patients in the young and middle aged groups.

Conclusion

The findings of this study demonstrate that WC may be a useful predictor of hypertension incidence among demographic and anthropometric factors in Korean adults. In addition, WC in the young population was more sensitive to the incidence of hypertension than in the elderly population.

Tobacco Smoke Exposure Association With Lipid Profiles and Adiposity Among U.S. Adolescents

PURPOSE

We investigated the association between tobacco smoke exposure (TSE) as measured by serum cotinine and lipoprotein cholesterols and adiposity in adolescents.

METHODS

We performed a secondary analysis of 1999-2012 National Health and Nutrition Examination Survey data including participants 12-19 years old. We examined TSE: unexposed (<.05 ng/mL), passively exposed (.05-2.99 ng/mL), and actively exposed (≥3 ng/mL); lipid profiles: total cholesterol, high-density lipoprotein cholesterol (HDL-C), non-HDL-C, low-density lipoprotein cholesterol (LDL-C), and triglycerides; and adiposity: body mass index z-score (BMIZ), waist circumference (WC), and waist-to-height ratio (WHtR). Covariates were age, sex, race/ethnicity, income, diet, and physical activity. Multiple regression models were used to assess the association between TSE and lipid profile variables separately, and then TSE and adiposity measures separately, adjusting for covariates. We performed logistic regression to examine the association of TSE with body mass index and WHtR classifications.

RESULTS

Of the 11,550 participants, 41.7% were unexposed to tobacco smoke, 40.5% were passively exposed, and 17.8% were actively exposed. Compared with unexposed, participants with active TSE had lower total cholesterol, lower HDL-C, and higher triglycerides; higher BMIZ, higher WC, and higher WHtR; participants with passive TSE had lower HDL-C, higher total cholesterol, and higher LDL-C; higher BMIZ, higher WC, and higher WHtR. Participants actively exposed were at increased odds of being obese or WHtR ≥.65, and those passively exposed were at increased odds of being overweight, obese, or WHtR ≥.65.

CONCLUSIONS

Active TSE and passive TSE are differentially associated with factors within the lipid profile and adiposity, independent of covariates. TSE prevention efforts should start as early as childhood and continue throughout adolescence and adulthood.

Interventions to prevent global childhood overweight and obesity: a systematic review

In view of the prevalence, health consequences, and costs of childhood obesity, there has been substantial interest in identifying effective interventions to prevent excess weight gain in young people. In this systematic review, we expand on previous reviews of obesity prevention interventions by including recent studies (until May 23, 2017) from all parts of the world. We searched MEDLINE, Embase, CINAHL Plus, Web of Science, CAB Abstracts, and PAIS Index and included randomised controlled trials, quasi-experimental studies, or natural experiments with: (1) a control group; (2) minimum follow-up of 12 months for community-based and home-based interventions or 6 months for school-based and preschool-based interventions; and (3) a primary outcome of BMI, BMI Z score, BMI percentile, body fat percentage, skinfold thickness, waist circumference, or prevalence of overweight or obesity. School-based interventions with combined diet and physical activity components and a home element (n=41) had greatest effectiveness; evidence in support of the effect of preschool-based (n=6), community-based (n=7), and home-based (n=2) interventions was limited by a paucity of studies and heterogeneity in study design. The effectiveness of school-based interventions that combined diet and physical activity components suggests that they hold promise for childhood obesity prevention worldwide. More research with rigorous evaluation and consistent reporting is needed in non-school settings and in combinations of settings.

Current data in Greek children indicate decreasing trends of obesity in the transition from childhood to adolescence; results from the National Action for Children's Health (EYZHN) program

Introduction

The aim of the study is to present the most recent estimates of obesity (total and central) prevalence in Greek children and associated risk factors.

Methods

Population data are derived from a yearly, school-based health survey polled in 2015 on 336,014 (51% boys) children aged 4 to 17 years old from almost 40% of all schools of primary and secondary education in Greece. Anthropometric and physical fitness measurements were obtained by trained investigators. Dietary habits, physical activity status, sedentary activities and sleeping hours were assessed through self-completed questionnaires. The gender and age-specific Body Mass Index (BMI) cut-off points were used in order to define BMI groups.

Results

The prevalence of overweight and obesity in the whole population was 22.2% and 9.0% in boys and 21.6% and 7.5% in girls, respectively. Obesity presented decreasing trends in the transition from childhood to adolescence. Central obesity was diagnosed in 95.3% and 93.5% of the simple obese boys and girls, respectively, in almost two to three of overweight children (68.6% of boys and 64.3% of girls), and in 12% of normal weight children. Age, physical fitness, low adherence to Mediterranean diet, insufficient sleeping hours, inadequate physical activity levels and increased screen time were all associated with higher odds of total and central obesity.

Conclusions

Serious and urgent actions need to be taken from public health policy makers in order not only to prevent a further increase in obesity rates but, more important, to treat obesity and/or the obesity associated co-morbidities.

Fully automated segmentation and quantification of visceral and subcutaneous fat at abdominal CT: application to a longitudinal adult screening cohort

OBJECTIVE

To investigate a fully automated CT-based adiposity tool, applying it to a longitudinal adult screening cohort.

METHODS

A validated automated adipose tissue segmentation algorithm was applied to non-contrast abdominal CT scans in 8852 consecutive asymptomatic adults (mean age, 57.1 years; 3926 M/4926 F) undergoing colonography screening. The tool was also applied to follow-up CT scans in a subset of 1584 individuals undergoing longitudinal surveillance (mean interval, 5.6 years). Visceral and subcutaneous adipose tissue (VAT and SAT) volumes were segmented at levels T12-L5. Primary adipose results are reported herein for the L1 level as mean cross-sectional area. CT-based adipose measurements at initial CT and change over time were analyzed.

RESULTS

Mean VAT values were significantly higher in males (205.8 ± 107.5 vs 108.1 ± 82.4 cm²; p < 0.001), whereas mean SAT values were significantly higher in females (171.3 ± 111.3 vs 124.3 ± 79.7 cm²; p < 0.001). The VAT/SAT ratio at L1 was three times higher in males (1.8 ± 0.7 vs 0.6 ± 0.4; p < 0.001). At longitudinal follow-up CT, mean VAT/SAT ratio change was positive in males, but negative in females. Among the 502 individuals where the VAT/SAT ratio increased at follow-up CT, 333 (66.3%) were males. Half of patients (49.6%; 786/1585) showed an interval increase in both VAT and SAT at follow-up CT.

CONCLUSION

This robust, fully automated CT adiposity tool allows for both individualized and population-based assessment of visceral and subcutaneous abdominal fat. Such data could be automatically derived at abdominal CT regardless of the study indication, potentially allowing for opportunistic cardiovascular risk stratification. Advances in knowledge: The CT-based adiposity tool described herein allows for fully automated measurement of visceral and subcutaneous abdominal fat, which can be used for assessing cardiovascular risk, metabolic syndrome, and for change over time.

Comparison of Body Composition Metrics for United States Air Force Airmen

Background

The United States Air Force currently uses AFI 36-2905 for cardiovascular fitness standards and evaluation. Regarding its fitness test, the Air Force considers waist circumference (WC) twice as important as push-ups or sit-ups. Because of this weighting, one assumes that the Air Force considers WC relatively correlated with overall fitness or at least cardiovascular fitness. To our knowledge, the Air Force has not considered on a large scale how body mass index (BMI), height-to-weight ratio (H-W), or waist-to-height ratio (WHtR) compares with WC with respect to its fitness test.

Methods

Using a 5.38 million record database from the Air Force Fitness Management System, we evaluated how WC, BMI, WHtR, and H-W correlate with fitness as assessed by the 1.5-mile run in addition to total fitness, which incorporates the 1.5-mile run time, number of push-ups and sit-ups. As this previously collected data were anonymous to us, this study fell under the definition of exempt status and approved by the institutional review board overseeing Joint Base San Antonio. For each waist metric, we performed a simple ordinary least squares regression to ascertain the correlation between that particular metric and either run time or total fitness; when incorporating more than one explanatory variable or covariate (to control for age and/or sex), we performed multiple ordinary least squares regressions. Due to the large database size and to mitigate against a type I error, we used an alpha of 0.001 for all statistical hypothesis tests.

Findings

Approximately 18% of the 5.38 million records belonged to women. With respect to sex differences, males appeared noticeably faster and performed more push-ups on average than females. The number of sit-ups completed was more comparable, with males having a slight advantage. Males also appeared to have larger WC, BMI, H-W, and WHtR measurements. We compared the ordinary least squares results between WC, H-W, WHtR, and BMI and ranked them by R2. Models varied in R2 from 1% to 46% depending on the covariates in the model, with sex having a greater effect than age. Whether individually or adjusting for age and sex, WHtR performed better than the other body composition variables with an average rank score of 1.1 and a median improvement of approximately 4% to the current Air Force metric of WC.

Discussion

From our findings, we present a 20-point WHtR scoring system for the Air Force to use in lieu of its traditional usage of WC. We used this assessment chart to score all Airmen in our database and compared the results to their current scores on the abdominal circumference portion of the test with respect to predicting run time, after accounting for sex, age, and number of push-ups and sit-ups. The R2 value improved from 40.3 to 43.6, a relative improvement of approximately 8%, a fairly significant effect given the database consisted of over 5 million records. Future studies should investigate the longitudinal effect of varying waist metrics over time on run time or total fitness performance.

FTO genotype, dietary protein intake, and body weight in a multiethnic population of young adults: a cross-sectional study

BACKGROUND

Variation in the fat mass and obesity-associated gene (FTO) has been associated with susceptibility to obesity, but the association appears to be modified by diet. We investigated whether dietary protein intake modifies the association between FTO variant rs1558902 and body mass index (BMI) and waist circumference in young adults (n = 1491) from the cross-sectional Toronto Nutrigenomics and Health Study.

RESULTS

Lifestyle, genetic, anthropometric, and biochemical data were collected and diet was assessed using a Toronto-modified Willett Food Frequency Questionnaire. General linear models stratified by ethnicity and adjusted for age, sex, and total energy intake were used to examine the association between FTO genotypes and measures of body weight, and whether protein intake modified any of the associations. East Asians who were homozygous for the rs1558902 risk allele (A) had a greater BMI (p = 0.004) and waist circumference (p = 0.03) than T allele carriers. This association was not observed in individuals of Caucasian or South Asian ancestry. Among East Asians, a significant FTO-protein interaction was observed for BMI (p = 0.01) and waist circumference (p = 0.007). Those with low protein intake (≤ 18% total energy intake) who were homozygous for the rs1558902 risk allele (A) had significantly higher BMI (p <  0.0001) and waist circumference (p = 0.0006) compared to carriers of the T allele. These associations were absent in the high protein intake group (> 18% total energy intake). Compared to Caucasians and South Asians, East Asians consumed a significantly higher ratio of animal-to-plant protein (p <  0.05).

CONCLUSIONS

These findings suggest that high dietary protein intake may protect against the effects of risk variants in the FTO gene on BMI and waist circumference.

Wrist circumference is associated with increased systolic blood pressure in children with overweight/obesity

Wrist circumference is a clinical marker for insulin-resistance in overweight/obese children and adolescents. Insulin resistance is considered a major determinant of increased vascular resistance and hypertension. The aim of the study was to investigate the association between wrist circumference and systolic (S) and diastolic (D) blood pressure (BP) in a population of overweight/obese children and adolescents. A population of 1133 overweight/obese children and adolescents (n = 1133) were consecutively enrolled. Multivariate regression analyses were used to investigate the influence of independent variables on the variance of BP. The prevalence of hypertension was 21.74% in males and 28.95% in females (p = 0.048). The results showed that SBP was significantly associated with wrist circumference in both genders (p < 0.0001 for both comparisons). We found no association between DBP and wrist circumference in either gender. Wrist circumference accounted for 17% of the total variance of SBP in males and 14% in females. Wrist circumference, a marker of insulin resistance, is associated with increased SBP in overweight/obese children and adolescents, suggesting a role of insulin resistance in the pathogenesis and development of hypertension.

The association between a body shape index and cardiovascular risk in overweight and obese children and adolescents

A Body Shape Index (ABSI) and normalized hip circumference (Hip Index, HI) have been recently shown to be strong risk factors for mortality and for cardiovascular disease in adults. We conducted an observational cross-sectional study to evaluate the relationship between ABSI, HI and cardiometabolic risk factors and obesity-related comorbidities in overweight and obese children and adolescents aged 2–18 years. We performed multivariate linear and logistic regression analyses with BMI, ABSI, and HI age and sex normalized z scores as predictors to examine the association with cardiometabolic risk markers (systolic and diastolic blood pressure, fasting glucose and insulin, total cholesterol and its components, transaminases, fat mass % detected by bioelectrical impedance analysis) and obesity-related conditions (including hepatic steatosis and metabolic syndrome). We recruited 217 patients (114 males), mean age 11.3 years. Multivariate linear regression showed a significant association of ABSI z score with 10 out of 15 risk markers expressed as continuous variables, while BMI z score showed a significant correlation with 9 and HI only with 1. In multivariate logistic regression to predict occurrence of obesity-related conditions and above-threshold values of risk factors, BMI z score was significantly correlated to 7 out of 12, ABSI to 5, and HI to 1. Overall, ABSI is an independent anthropometric index that was significantly associated with cardiometabolic risk markers in a pediatric population affected by overweight and obesity.

High body mass index in children with sickle cell disease: a retrospective single-centre audit

OBJECTIVE

To assess the prevalence of high body mass index (BMI) in children with sickle cell disease and assess correlation between BMI and disease severity.

DESIGN

Retrospective chart review followed by statistical analysis.

SETTING

A single tertiary paediatric clinic in inner city London.

PATIENTS

All patients with sickle cell disease, including homozygous haemoglobin (HbSS) and compound heterozygous Hb (HbSC), age 2-18 years receiving clinical care at the centre, were included in the study.

INTERVENTIONS

Height and weight measurements, steady-state laboratory blood tests, hospital admission rates, adjunct therapy such as hydroxycarbamide or blood transfusions and obstructive sleep apnoea (OSA) data were obtained from the hospital electronic patient records.

MAIN OUTCOME MEASURES

To study the prevalence of high BMI and to identify any correlation between BMI and disease severity.

RESULTS

385 patients were included. 64 children (17%) were overweight or obese, of which a significantly higher number of children with HbSC were obese or overweight (23 out of 91, 25%) compared with those with HbSS (36 out of 273, 13%), p≤0.001. No correlation was found between high BMI and presence of OSA, and markers of disease severity such as admission rates, fetal haemoglobin or lactate dehydrogenase levels.

CONCLUSIONS

High BMI did not correlate with disease severity in this cohort of patients with sickle cell disease. Obesity was more prevalent in females and those with HbSC. Further prospective studies are needed to determine long-term effects of BMI in disease severity and outcome.

Neck circumference and its association with cardiometabolic risk factors: a systematic review and meta-analysis

BACKGROUND

Recently, neck circumference (NC) has been used to predict the risk of cardiometabolic factors. This study aimed to perform a systematic review and meta-analysis to examine: (i) the sensitivity (SE) and specificity (SP) of NC to predict cardiometabolic risk factors and (ii) the association between NC and the risk of cardiometabolic parameters.

METHODS

A systematic search was conducted through PubMed/Medline, Institute of Scientific Information, and Scopus, until 2017 based on the search terms of metabolic syndrome (MetS) and cardio metabolic risk factors. Random-effect model was used to perform a meta-analysis and estimate the pooled SE, SP and correlation coefficient (CC).

RESULTS

A total of 41 full texts were selected for systematic review. The pooled SE of greater NC to predict MetS was 65% (95% CI 58, 72) and 77% (95% CI 55, 99) in adult and children, respectively. Additionally, the pooled SP was 66% (95% CI 60, 72) and 66% (95% CI 48, 84) in adult and children, respectively. According to the results of meta-analysis in adults, NC had a positive and significant correlation with fasting blood sugar (FBS) (CC: 0.16, 95% CI 0.13, 0.20), HOMA-IR (0.38, 95% CI 0.25, 0.50), total cholesterol (TC) (0.07 95% CI 0.02, 0.12), triglyceride (TG) concentrations (0.23, 95% CI 0.19, 0.28) and low density lipoprotein cholesterol (LDL-C) (0.14, 95% CI 0.07, 0.22). Among children, NC was positively associated with FBS (CC: 0.12, 95% CI 0.07, 0.16), TG (CC: 0.21, 95% CI 0.17, 0.25), and TC concentrations (CC: 0.07, 95% CI 0.02, 0.12). However, it was not significant for LDL-C.

CONCLUSION

NC has a good predictive value to identify some cardiometabolic risk factors. There was a positive association between high NC and most cardiometabolic risk factors. However due to high heterogeneity, findings should be declared with caution.

Comparing measures of general and abdominal adiposity as predictors of blood pressure in college students

OBJECTIVE

To compare anthropometric measures of body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), and sagittal abdominal diameter (SAD) as predictors of blood pressure in college students.

PARTICIPANTS

Students (N = 116) were recruited from November 2012 to May 2014 at an urban university and rural community colleges.

METHODS

Students underwent a brief physical examination during which anthropometric measures were obtained and blood pressure was measured. Covariates were measured using self-reported questionnaires. Hierarchical multiple linear regressions were used for the data analysis.

RESULTS

All anthropometric measures were predictive of systolic (SBP) and diastolic blood pressure (DBP). WC was the strongest predictor of SBP (β = .582, p < .01) explaining an additional 3-4% of the variance than BMI, WHtR, or SAD. The measures were similar in predicting DBP. WC predicted SBP independent of BMI.

CONCLUSIONS

Clinicians should consider using WC to assess the risk for hypertension in college students.

Associations between general and central obesity and hypertension among children: The Childhood Obesity Study in China Mega-Cities

In this study, we examined the associations of general and central obesity and hypertension among Chinese children. Data was collected from 1626 children aged 7-16 years and their parents in four mega-cities across China. Mixed effect models examined associations of general and central obesity with hypertension, and between body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), systolic blood pressure (SBP) and diastolic blood pressure (DBP). The prevalence of general obesity, central obesity, and hypertension among the children was 11.1%, 19.7%, and 9.0%, respectively. More boys had general and central obesity than girls (15.2% vs. 6.9%; 27.4% vs. 11.7%, respectively; both P < 0.0001). Sex difference in hypertension rate was not statistically significant (9.3% in boys vs. 8.8% in girls, P = 0.7341). Both SBP and DBP were positively associated with BMI, WC, and WHtR, regardless of sex and region. General obesity (OR = 5.94, 95% confidence interval [CI]: 3.69-9.55) and central obesity (OR = 3.45, 95% CI: 2.27-5.23) were strongly associated with hypertension. The prevalence of general obesity, central obesity, and hypertension was high among Chinese children in the four mega-cities across China. Children's BMI, WC, and WHtR were positively associated with their SBP and DBP. Obese children were 3-6 times more likely to have hypertension.

Carbohydrate Taste Sensitivity Is Associated with Starch Intake and Waist Circumference in Adults

Background: Recent studies have proposed that humans may perceive complex carbohydrates and that sensitivity to simple carbohydrates is independent of sensitivity to complex carbohydrates. Variation in oral complex carbohydrate sensitivity may influence food consumption.Objective: This study aimed to investigate the associations between oral complex carbohydrate sensitivity, anthropometry, and dietary intake in adults.Methods: We assessed oral sensitivity to complex carbohydrates (maltodextrin and oligofructose) by measuring detection thresholds (DTs) and suprathreshold intensity perceptions (STs) for 34 participants, including 16 men (mean ± SEM age : 26.2 ± 0.4 y; range: 24-30 y) and 18 women (age: 29.4 ± 2.1 y; range: 24-55 y). We also measured height, weight, and waist circumference (WC) and participants completed a 4-d food diary and a food-frequency questionnaire.Results: Measurements of oral sensitivity to complex carbohydrates were significantly correlated with WC and dietary energy and starch intakes (DT: r = -0.38, P < 0.05; ST: r = 0.36-0.48, P < 0.05). When participants were grouped into tertiles, there were significant differences in WC and total energy or starch intakes for those who were more sensitive or experienced high intensity compared with those who were less sensitive or experienced low intensity. Being more sensitive or experiencing high intensity was associated with greater energy (7968-8954 kJ/d) and starch (29.1-29.8% of energy) intakes and a greater WC (88.2-91.4 cm) than was being less sensitive or experiencing low intensity (6693-7747 kJ/d, 20.9-22.2% of energy, and 75.5-80.5 cm, respectively).Conclusion: Complex carbohydrate sensing is associated with WC and consumption of complex carbohydrates and energy in adults. This trial was registered at anzctr.org.au as ACTRN12616001356459.

Caregiver feeding practices and weight status among African American adolescents: The Jackson Heart KIDS Pilot Study

Adolescence is a stage in the life course during which youth become more autonomous in their health behaviors. Overweight and obesity during this developmental period are associated with short- and long-term physical and emotional morbidity, and African American youth are at pronounced risk for these health outcomes. The style of parenting employed by caregivers influences health behaviors in children, though the persistence of this influence into adolescence is not clear. This study examined associations among caregiver feeding practices, body mass index z-score (zBMI), and waist circumference (WC) in a cohort of 212 African American adolescents (50.5% girls; Mage=15.16years). Participants were children and grandchildren of individuals enrolled in the Jackson Heart Study, a prospective epidemiologic evaluation of cardiovascular disease among African Americans based in Jackson, Mississippi. Youth zBMI and WC were primary outcomes, and caregivers completed the Child Feeding Questionnaire, an assessment of attitudes, beliefs, and practices related to obesity proneness. Regression analyses revealed that while controlling caregiver feeding practices were associated with zBMI and WC, perceived responsibility for the type and amount of food provided to adolescents was not related to weight status. Among younger adolescents, more oversight of their eating practices was related to higher zBMI. Similarly, boys whose intake of unhealthy foods was restricted were more likely to have higher zBMI and WC. Results suggest that caregiver feeding practices continue to be associated with weight status during adolescence, and underscore the importance of culturally and developmentally appropriate prevention and intervention efforts targeting overweight and obesity.

Recent Trends in Body Mass Index and Waist Circumference among Children and Adolescents in Shandong China

BACKGROUND

The present study examined the recent trends in body mass index (BMI) and waist circumference (WC), and the prevalence of general and abdominal obesity among children and adolescents in Shandong, China.

METHODS

Data for this study were obtained from two cross-sectional surveys of schoolchildren carried out in 2010 and 2014 in Shandong Province, China. A total of 72 755 students aged 7-18 years were included in this study. The BMI cutoff points recommended by the International Obesity Task Force were used to define overweight and general obesity. Abdominal obesity was defined as waist-to-height ratio (WHtR) ≥ 0.5. Both BMI and WHtR were used to define three types of obesity as follows: general obesity only, abdominal obesity only and combined obesity.

RESULTS

For both boys and girls, an increasing trend in BMI and WC was observed between 2010 and 2014 (p < 0.01), WC has increased faster than BMI. The sum of the prevalence of the three types of obesity increased from 16.63% (boys) and 8.13% (girls) in 2010 to 20.37% (boys) and 11.61% (girls) in 2014 (p < 0.01).

CONCLUSION

WC and abdominal obesity increased faster than BMI and general obesity among children and adolescents between 2010 and 2014. This study also suggested that distinguishing the types of obesity and examining the prevalence of various types of obesity are useful in practice.

Waist-to-height ratio and sedentary lifestyle as predictors of metabolic syndrome in children in Ecuador

OBJECTIVE

To determine the predictors and prevalence of metabolic syndrome (MS) and the presence of vascular inflammation in apparently-normal children (10-15 years) of both sexes in Guayaquil, Ecuador.

STUDY DESIGN AND METHODS

We included 395 apparently-healthy students from a middle-income school in a cross-sectional survey. Informed consent was obtained from students and parents. Anthropometric measurements including blood pressure (BP), body mass index (BMI) and waist-to-height ratio (WHtR), and blood tests were recorded. Vascular inflammation parameters were assessed. Percentiles of the different parameters were used, and MS was defined according to National Cholesterol Education Program Adult Treatment Panel III criteria (NCEP-ATPIII). Waist circumference>P 75, blood pressure>P 90, glucose>100mg/dl, triglycerides>100mg/dl, HDL<45mg/dl. If 3 of the 5 criteria were present, this was considered MS.

RESULTS

The mean age was 12 years (186 boys, 209 girls). The overall prevalence of MS was 9.37% (6.33% in girls, 3.04% in boys). Sustained hypertension was detected in 6.6% of children and pre-hypertension in 7.1%. Obesity was found in 1.8% of subjects, and overweight in 15.2%. Triglycerides has a RR 2.34 (1.97-2.76); HOMA index has a RR 1.97(1.62-2.40); HDL cholesterol has a RR 1.84(1.58-2.13); Insulin level has a RR 1.53(1.40-1.67) and interleukin 6 has RR 1.83(1.20-2.79). Serum glucose, total cholesterol and LDL-Cholesterol had no association with the metabolic syndrome. HDL-Cholesterol<45mg/dl and triglyceride>100mg/dl were present in 70% of subjects with MS. The WHtR threshold≥0.5 was 100% sensitive in both sexes (67% specificity in boys and 69% in girls). There were significant associations between the WHtR and pre-hypertension and sedentary lifestyle (P<0.001 and P<0.003 respectively). A WHtR value of ≥0.50 indicated a 2.2-fold increased risk of MS compared with normal WHtR, and normal weight.

CONCLUSIONS

A WHtR≥0.5 was 100% sensitive in detecting MS in 10-15 year-old boys and girls in the normal or overweight range of the BMI. This assessment is a simple and practical tool for use in population-based studies of cardiovascular risk. When combined with pre-hypertension and a sedentary lifestyle, the WHtR is highly sensitive in predicting MS.

The Prevalence of Overfat Adults and Children in the US

The overfat condition is defined as excess body fat sufficient to impair health. The problem exists in most overweight and obese individuals and can also occur in those who are normal-weight and non-obese, often due to excess abdominal fat. Despite previous indications that the prevalence overweight and obesity is leveling, these conditions are currently at their highest levels in US history. Our review estimated the number of overfat Americans at 91% for adults and 69% for children. The primary purpose of this review was to build upon previous estimations of overfat prevalence in developed countries by using new data from the Centers for Disease Control and Prevention to estimate the overfat prevalence in American adults (≥20 years) and children (2-19 years), and to expand the definition of overfat as excess body fat associated with at least one additional risk factor of impaired cardiometabolic or physical health. The secondary goals are to highlight the role of dietary sugar as a primary cause of the overfat pandemic and mention new data showing the increased prevalence of exercise that parallels the rising prevalence of overfat to further emphasize the secondary role exercise may play in fat loss. Current public health guidelines to address the overfat pandemic may require more emphasis on reducing the consumption of refined carbohydrates, including added sugars.

Validation of surrogate markers for metabolic syndrome and cardiometabolic risk factor clustering in children and adolescents: A nationwide population-based study

Prevalence of metabolic syndrome (MetS) in children is increasing and identifying the risk factors for MetS during childhood is an important first step to prevent chronic diseases later in life. The aim of the present study was to evaluate the prevalence of MetS and cardiometabolic risk factor (CMRF) clustering among Korean children and adolescents and to validate the associated anthropometric and laboratory surrogate markers. We used data from the 2011–2014 Korean National Health and Nutrition Examination Survey. In total, data for 2,935 subjects (1539 boys, 52.6%) aged 10–19 years were assessed. MetS was defined by central obesity plus any two or more of CMRFs such as abdominal obesity, hypertension, hyperglycemia, hypertriglyceridemia, and decreased high density lipoprotein cholesterol (HDL-C) using the International Diabetes Federation criteria for children and adolescents. The presence of two or more CMRFs was classified as CMRF clustering. The prevalence of MetS and CMRF clustering in this group was found to be 1.8% and 8.9%, respectively. The receiver operating characteristic analysis of MetS and CMRF clustering, and the area under the curve (95% confidence interval) of surrogate markers revealed that the waist circumference to height ratio [0.960 (95% CI 0.959–0.960), cut-off 0.491] showed the highest predictability for MetS whereas triglyceride to HDL-C ratio [0.891 (95% CI 0.891–0.892), cut-off 2.63] showed the highest predictability for CMRF clustering. Long-term follow-up is needed for further validation.

Sleep Duration and Adiposity in Early Childhood: Evidence for Bidirectional Associations from the Born in Bradford Study

Study Objectives:

To examine independent associations of sleep duration with total and abdominal adiposity, and the bidirectionality of these associations, in a young biethnic sample of children from a disadvantaged location.

Methods:

Child sleep duration (h/day) was parent-reported by questionnaire and indices of total (body weight, body mass index, percent body fat (%BF), sum of skinfolds) and abdominal adiposity (waist circumference) were measured using standard anthropometric procedures at approximately 12, 18, 24, and 36 months of age in 1,338 children (58% South Asian; 42% White). Mixed effects models were used to quantify independent associations (expressed as standardised β-coefficients (95% confidence interval (CI)) of sleep duration with adiposity indices using data from all four time-points. Factors considered for adjustment in models included basic demographics, pregnancy and birth characteristics, and lifestyle behaviours.

Results:

With the exception of the sum of skinfolds, sleep duration was inversely and independently associated with indices of total and abdominal adiposity in South Asian children. For example, one standard deviation (SD) higher sleep duration was associated with reduced %BF by -0.029 (95% CI: −0.053, −0.0043) SDs. Higher adiposity was also independently associated with shorter sleep duration in South Asian children (for example, %BF: β = -0.10 (-0.16, -0.028) SDs). There were no significant associations in White children.

Conclusions:

Associations between sleep duration and adiposity are bidirectional and independent among South Asian children from a disadvantaged location. The results highlight the importance of considering adiposity as both a determinant of decreased sleep and a potential consequence.

Relationship Between Adherence to Individual Goals Within the 5-2-1-0 Guidelines for Obesity Prevention and Number of PACER Laps in Adolescents

BACKGROUND

The purpose of this study was to evaluate the relationship between adolescents' adherence to the 5-2-1-0 goals and the number of completed Progressive Cardiovascular Endurance Run (PACER) laps.

METHODS

Participants included 1792 students aged 10 to 16 years who were randomly selected across 9 data collection periods between 2012 and 2014. The Survey of Physical Activity and Nutrition was used to measure time spent in physical activity and sedentary behavior, and dietary intake and the dependent variable was the number of PACER laps achieved. The Kruskal-Wallis test and pairwise post hoc comparisons were conducted.

RESULTS

Only 0.95% (N = 17) participants met all 4 goals outlined within the 5-2-1-0 guidelines. Whereas 10.04% met 3 (N = 180), 41.63% met 2 (N = 746), 34.99% met 1 (N = 627), and 12.39% did not meet any goals (N = 222). Pairwise comparisons indicated there were significant differences: between groups not meeting any of the 5-2-1-0 goals and other groups (meeting one goal [p = .000], 2 goals [p = .000], 3 goals [p = .000], and all 4 [p = .008]).

CONCLUSIONS

The positive relationship between PACER laps and adherence to the 5-2-1-0 goals suggests targeted and sequential behavioral changes may have positive implications on adolescents' cardiovascular fitness and body mass index.

The associations of body composition and anthropometric measures with carotid intima-media thickness in obese and non-obese schoolchildren: A possible predictor for cardiovascular diseases

Background

Increased carotid intima-media thickness is one of the predictors of future cardiovascular diseases. However, it is still unknown which body composition parameter or anthropometric measure is the best predictor for carotid intima-media thickness change among children and young adolescents.

Objective

To investigate the associations of body composition and anthropometric measures with carotid intima-media thickness among a group of obese and normal bodyweight schoolchildren.

Methods

A total of 125 schoolchildren (10–15 years) were recruited from four public schools in Amman, Jordan. Of them, 60 (29 boys and 31 girls) were normal bodyweight students and 65 (35 boys and 30 girls) were obese students. Anthropometric measures, fat mass and fat-free mass were determined. Carotid intima-media thickness of the common artery was measured using high-resolution B-mode ultrasound.

Results

Compared to normal bodyweight students, obese participants exhibited greater carotid intima-media thickness (mm) (0.45 ± 0.10 vs. 0.38 ± 0.08, p = 0.002) and fat-free mass (kg) (48.01 ± 11.39 vs. 32.65 ±7.65, p < 0.001). Pearson’s correlation coefficient and linear regression analysis revealed significant associations ( p≤0.05) between mean carotid intima-media thickness and body mass index, waist circumference, hip circumference, waist-to-hip ratio, fat mass and fat-free mass. Stepwise linear regression analysis revealed that waist circumference was the only measure that was statistically significant ( p ≤ 0.05) with mean carotid intima-media thickness (r2 = 0.129, p = 0.002).

Conclusions

Obesity is related to greater carotid intima-media thickness and other cardiovascular risk factors among schoolchildren. Waist circumference is more sensitive in predicting increased carotid intima-media thickness than other body composition or anthropometric measures. Waist circumference measurement in the analysis of future studies assessing the cardiovascular risk among obese children is warranted.

Neck circumference and clustered cardiovascular risk factors in children and adolescents: cross-sectional study

OBJECTIVE

Early detection of cardiovascular disease (CVD) risk factors, such as obesity, is crucial to prevent adverse long-term effects on individuals' health. Therefore, the aims were: (1) to explore the robustness of neck circumference (NC) as a predictor of CVD and examine its association with numerous anthropometric and body composition indices and (2) to release sex and age-specific NC cut-off values to classify youths as overweight/obese.

DESIGN

Cross-sectional study.

SETTING

23 primary schools and 17 secondary schools from Spain.

PARTICIPANTS

2198 students (1060 girls), grades 1-4 and 7-10.

MEASURES

Pubertal development, anthropometric and body composition indices, systolic and diastolic blood pressure (SBP and DBP, respectively), cardiorespiratory fitness, blood sampling triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), glucose and inflammatory markers. Homoeostasis model assessment (HOMA-IR) and cluster of CVD risk factors were calculated.

RESULTS

NC was negatively associated with maximum oxygen consumption (R2=0.231, P<0.001 for boys; R2=0.018, P<0.001 for girls) and adiponectin (R2=0.049, P<0.001 for boys; R2=0.036, P<0.001 for girls); and positively associated with SBP, DBP, TC/HDL-c, TG, HOMA, complement factors C-3 and C-4, leptin and clustered CVD risk factor in both sexes (R2 from 0.035 to 0.353, P<0.01 for boys; R2 from 0.024 to 0.215, P<0.001 for girls). Moreover, NC was positively associated with serum C reactive protein and LDL-c only in boys (R2 from 0.013 to 0.055, P<0.05).

CONCLUSION

NC is a simple, low-cost and practical screening tool of excess of upper body obesity and CVD risk factors in children and adolescents. Paediatricians can easily use it as a screening tool for overweight/obesity in children and adolescents. For this purpose, sex and age-specific thresholds to classify children and adolescents as normal weight or overweight/obese are provided.

Cumulative Risk Exposure and Waist Circumference in Preschool-Aged Children: the Mediating Role of Television and Moderating Role of Sex

BACKGROUND

Children exposed to multiple stressors are more likely to be overweight, but little is known about the mechanisms explaining this association.

PURPOSE

This cross-sectional study examined whether children exposed to multiple stressors had higher waist circumference, and whether this association was mediated through children's television time.

METHODS

Participants were 319 parent-child dyads. Children were 2-5 years old and had at least one overweight parent (BMI ≥ 25 kg/m2). Data were collected at baseline of a larger childhood obesity prevention study and included information on psychosocial stressors (e.g., parenting stress), demographic stressors (e.g., low income), children's television time, and children's waist circumference. Two cumulative risk scores were created by summing stressors in each domain (demographic and psychosocial). Mediation and moderated mediation analyses were conducted.

RESULTS

Indirect effects of both cumulative risk scores on waist circumference through television time were not significant; however, moderated mediation analyses found significant moderation by gender. The indirect effects of both risk scores on waist circumference through television time were significant and positive for girls, but near-zero for boys.

CONCLUSIONS

Reducing television time should be explored as a strategy for buffering against the negative health effects of exposure to multiple stressors among girls. Longitudinal and intervention research is needed to confirm these results and to identify mediating factors between cumulative risk and body weight among boys.

Association between adiposity indicators, metabolic parameters and inflammatory markers in a sample of female adolescents

OBJECTIVE

The aim of this study was to investigate the association between total and abdominal adiposity with metabolic parameters and inflammatory markers, in female adolescents.

SUBJECTS AND METHODS

The sample consisted of 53 adolescents aged 13 to 17 years from a public school in Curitiba, Brazil. The adiposity indicators studied were body mass index (BMI), waist circumference (WC), trunk fat mass (TKFM), total fat mass (TFM) and body fat percentage (BF%) measured by dual-energy X-ray absorptiometry. The metabolic and inflammatory parameters studied were systolic blood pressure (SBP), diastolic blood pressure (DBP), glucose, insulin, homeostasis model assessment index for insulin resistance (HOMA-IR), lipids, C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), leptin, adiponectin and resistin.

RESULTS

Eighty percent of WC variation, 87% of TKFM and TFM, and 73% of BF% were predicted by BMI variation. There was a significant positive correlation between all indicators of adiposity with SBP, DBP, insulin, HOMA-IR, CRP and leptin. Triglycerides were positively correlated with BMI and WC, and adiponectin correlated negatively with BMI. TNF-α, IL-6, glucose, total cholesterol, and high- and low-density lipoprotein cholesterol did not correlate to the studied variables.

CONCLUSION

BMI showed a significant association with most of the parameters studied, and WC was slightly better than BMI to predict insulin resistance in this specific population.

Overfat Adults and Children in Developed Countries: The Public Health Importance of Identifying Excess Body Fat

The global overfat pandemic is a serious public health crisis that places a substantial burden on economic resources in developed countries. The term overfat refers to the presence of excess body fat that can impair health, even for normal weight non-obese individuals. Excess body fat is associated with cardiometabolic dysfunction, a clinical situation that can progressively worsen, potentially leading to various common disease risk factors, chronic diseases, increased morbidity and mortality, and reduced quality of life. The prevalence of overfat populations in 30 of the world’s most developed countries is substantially higher than recent global estimations, with the largest growth due to a relatively recent increased number of people with excess abdominal fat. Abdominal overfat is the most unhealthful form of this condition, so it is concerning that average waist circumference measures, generally indicative of abdominal overfat, have increased. Despite a leveling off appearance of being overweight and/or obese in some developed countries, the overfat pandemic continues to grow.

Body Mass Index in the Early Years in Relation to Motor Coordination at the Age of 5⁻7 Years

Physical activity (PA) and body mass index (BMI) are consistently associated with motor coordination (MC) in children. However, we know very little how BMI in early childhood associates with MC later in childhood. This study investigated associations between BMI in early childhood and BMI, PA, and MC in middle childhood. Children aged 5 to 7 years (n = 64, 32 girls) were measured for MC using Körperkoordinationstest für Kinder (KTK) and for moderate-to-vigorous PA (MVPA) using triaxial accelerometers. Prevailing body weight and height were measured, and information on weight and height in early years was based on parental report of child health care report cards. Age-adjusted BMIz scores were calculated on the basis of international growth curve references. Associations and the explained variability of MC were investigated by Pearson correlations and a hierarchical multiple regression analysis. Age and MVPA were found to be significantly associated with MC at middle childhood, in general. BMIz at middle childhood and at ages 4 and 5 years inversely explained 12% (p < 0.05), 6% (p > 0.05), and 7% (p > 0.05) of the variation in MC in girls after adjusting for covariates, respectively. In boys, BMIz scores did not show any trend of association with MC. This study suggests sex-specific mechanisms in the interplay between BMI and motor development in childhood.

Waist circumference shows the highest predictive value for metabolic syndrome, and waist-to-hip ratio for its components, in Spanish adolescents

Both waist circumference (WC) and waist-to-hip ratio (WHR) have been proposed as predictors of metabolic syndrome (MetS) in adolescents, but no consensus has been reached to date. This study hypothesizes that WC provides a greater predictive value for MetS in Spanish adolescents than WHR. A cross-sectional study was performed on 1001 adolescents (13.2 ± 1.2 years) randomly recruited from schools in southeast Spain. Anthropometric measures were correlated with the components of MetS (triglycerides, glucose, blood pressure, and high-density lipoprotein cholesterol) as well as inflammation markers (interleukin-6 and tumor necrosis factor-alpha , C-reactive protein, and ceruloplasmin). Receiver-operator curves were created to determine the predictive value of these variables for MetS. Boys had higher values of all anthropometric parameters compared with girls, but the prevalence of MetS was significantly higher in girls. WHR was the only parameter that correlated significantly with all biochemical and inflammatory variables in boys. In girls, WHR, body mass index, waist-to-height ratio, WC, and body fat percentage correlated only with plasma insulin levels, systolic and diastolic pressures, and ceruloplasmin. In both groups, all anthropometric measures were able to predict MetS (area under the curve > 0.94). In particular, WC was able to predict MetS with area under the curve = 1.00. However, WHR was able to predict a higher number of components of MetS. WHR was the anthropometric index that showed the highest predictive value for MetS components, whereas WC was the one that best predicted the MetS among the population of adolescents studied. These findings justify the need to incorporate WHR and WC determinations into daily clinical practice to predict the MetS.

Body Mass Disorders in Healthy Short Children and in Children with Growth Hormone Deficiency

The aim of the study was to determine the degree of adiposity and the incidence of body mass disorders, including abdominal obesity, in healthy short children and children with growth hormone deficiency. The study included 134 short children (height < 10th percentile) aged 7-15. In this cohort there were 63 (31 boys and 32 girls) children without diagnosed hormonal disorders and 71 patients (35 boys and 36 girls) with growth hormone deficiency. Basic somatic features were assessed and the study participants were categorized according to the percentage of body fat (%FAT), body mass index (BMI), and waist-to-height ratio (WHtR). We found that there were no significant differences in %FAT and the incidence of body weight disorders depending on gender or diagnosis. %FAT deficit was observed in 12-21% of the participants and underweight in almost every fourth child. Overweight involved 3-14% of the participants and obesity was diagnosed in isolated cases (0-3%); both were considerably lower compared to the estimates based on %FAT. Using the cut-off points of WHtR, abdominal adiposity was observed in 3-15% of the participants. In conclusion, quite a large number of short children (between 25 and 50%) are characterized by abnormal body fat or body mass index values. The results indicate a limited usefulness of BMI in evaluating the incidence of overweight and obesity in children characterized by a height deficit.