High Discrepancy in Abdominal Obesity Prevalence According to Different Waist Circumference Cut-Offs and Measurement Methods in Children: Need for Age-Risk-Weighted Standardized Cut-Offs?

Association between Gut Microbiota and Inflammation: Mediation Analysis Using Waist Circumference

Chronic low-grade inflammation (CLI) is implicated in the development of multiple metabolic diseases. The gut microbiota (GM) activates different signaling pathways and induces phenotypic changes, offering an exciting opportunity to treat CLI. We evaluated the mediation of waist circumference on the association of GM with serum cytokines. In this cross-sectional study of 331 children, we measured 5 gut bacterial species, namely, Lactobacillus (L.) casei, L. paracasei, L. reuteri, Staphylococcus (S.) aureus, and Akkermansia (A.) muciniphila, as well as anthropometry, serum cytokines, and other covariates. We evaluated adjusted regression models, path analysis, and structural equation modeling to obtain path coefficients (PCs) for direct, indirect (waist circumference-mediated), and total effects. We found that L. paracasei was directly associated with lower interleukin-10 (IL-10) levels (PC = -173.5 pg/mL). We also observed indirect associations between S. aureus with lower adiponectin levels (PC = -0.1 µg/mL and -0.09 µg/mL). Finally, A. muciniphila was indirectly associated with higher adiponectin levels (PC = 0.1 µg/mL). Our findings suggest the importance of considering the GM composition and waist circumference when evaluating inflammatory-related factors, providing a basis for future research to identify potential strategies to intervene in inflammatory processes and prevent metabolic diseases in childhood. [Figure: see text].

Relationship of body mass index to percent body fat determined by deuterium isotopic dilution and impedancemetry among Tunisian schoolchildren

Objectives

This study aims to evaluate the relation of body mass index (BMI) to fat mass among children by two techniques impedancemetry and deuterium oxide dilution (D2O).

Methods

This study was carried out in 156 schoolchildren aged between 8 and 11 years. The children received interrogation specifying lifestyle and food habits. Body composition was determined using the impedancemetry and D2O technique.

Results

The results showed a difference between the percentage of obese and overweight children according to BMIZ classification (30.1%), bioelectrical impedance method (14.7%) and D2O technique (42.9%). Despite the difference between the last two classifications, we found a significant correlation between body fat percentages determined by impedancemetry and D2O technique (r = 0.695, p<0.01). Bioelectrical impedance analysis underestimated %BF by 78.02% in overall children, by 70.05% in boys and by 84.73% in girls compared to D2O technique.

Conclusion

This study has demonstrated that the percentage of overweight and obesity varied according the methods used. Further development of body composition methods is needed in children for the real determination of the obesity prevalence and therefore a better monitoring of this public health problem.

Waist circumference percentiles for Hispanic-American children and comparison with other international references

INTRODUCTION

Waist circumference (WC) constitutes an indirect measurement of central obesity in children and adolescents.

OBJECTIVE

To provide percentiles of WC for Hispanic-American children and adolescents, and compare them with other international references.

MATERIALS AND METHODS

The sample comprised 13 289 healthy children between 6 and 18 years coming from public schools of middle and low socioeconomic levels in different parts of Argentina, Cuba, Spain, Mexico, and Venezuela. The LMS method to calculate WC percentiles was applied. Sex and age differences were assessed using Student's t test and ANOVA (SPSS v.21.0). Comparisons were established with references from the United States, Colombia, India, China, Australia, Kuwait, Germany, Tunisia, Greece, and Portugal.

RESULTS

WC increases with age in both sexes. Boys show higher WC in P3, P50, and P97. Comparison of 50th and 90th percentiles among populations from diverse sociocultural and geographical contexts shows high variability, not all justified by the measurement method.

DISCUSSION AND CONCLUSIONS

Specific WC percentiles for sex and age, and P90 cut-off points are provided; these values are potentially useful to assess central obesity in Hispanic-American adolescent children.

Haptoglobin Phenotypes Are Associated with the Postload Glucose and Insulin Levels in Pediatric Obesity

PURPOSE

Haptoglobin (Hp) is a protein involved in the acute-phase reaction of inflammation. Humans have three major phenotypes (Hp1-1, Hp1-2, and Hp2-2). Several studies have shown altered Hp regulation in adults with obesity and metabolic alterations. The Hp2-2 phenotype is associated with a high cardiovascular risk. Our aim was to investigate if Hp levels and the Hp2-2 phenotype are associated with glucose metabolism in pediatric obesity.

METHODS

We retrospectively studied 192 participants (92 males and 100 females), aged 4-18 years. Clinical and biochemical data were collected. The Hp phenotype (Hp1-1, Hp1-2, and Hp2-2) was identified through Western immunoblot.

RESULTS

Subjects carrying Hp1-1, Hp1-2, and Hp2-2 phenotypes were 13.6, 50.8, and 35.6%, respectively. Hp serum, fasting glucose, and insulin levels, as well as HOMA-IR, were similar among groups. Postload glucose and insulin levels (as insulin AUC) were progressively higher from the Hp1-1 to Hp2-2 phenotype.

CONCLUSION

To our knowledge, this is the first study on Hp phenotypes conducted in a pediatric population with obesity. We showed that the presence of Hp2 allele is associated with a worse response of glucose load in terms of both glucose and insulin levels. Thus, the Hp2-2 phenotype could predispose in pediatrics, at the same degree of obesity, to a worse glycemic and insulinemic compensation.

Waist circumference as high blood pressure predictor in school age children

Childhood hypertension is becoming more common with the increasing numbers of child obesity, which has encouraged new studies to identify a good anthropometric marker for high blood pressure levels. The objective this study was to identify the best anthropometric predictor of risk of hypertension in children between 8-10 years of age. The Children were evaluated for socioeconomic status and their blood pressure (BP), weight, height, waist circumference (WC) and percentage of body fat (PBF) were measured. The study included 445 children, of which 50.1% were females. The prevalence of obesity defined by body mass index (BMI) was 14.6%. Increased BP was found in 3.4% and 2.2% of the children, considering the pre-hypertension and hypertension classifications respectively. The arithmetic mean of BP value correlated significantly with BMI, WC and PBF. After height control, the correlations that were maintained significant were between WC and systolic blood pressure (SBP) and between WC and diastolic blood pressure (DBP). The variable with the highest predictive power of the occurrence of hypertension was WC. The results indicate that, in this population of children between 8 and 10 years old, WC is a measurement of higher value in predicting increased BP.

Low Diagnostic Accuracy of Body Mass Index-Based and Waist Circumference-Based References of Childhood Overweight and Obesity in Identifying Overfat among Chinese Children and Adolescents

This study aimed to investigate the diagnostic accuracy of body mass index- (BMI-) based and waist circumference- (WC-) based references for childhood overweight and obesity in screening overfat individuals among 2134 Chinese children and adolescents. In this study, overfat status was defined as over 25% body fat for boys and over 30% for girls. Childhood obesity or overweight was defined by four BMI-based references and two WC-based references. All BMI-based references for obesity showed low sensitivity (SE) (0.128–0.473) but high specificity (SP) (0.971–0.998) in detecting overfat individuals in the current population. SE values increased from 0.493 to 0.881 when BMI- and WC-based references for overweight were used to detect overfat individuals. All references for overweight showed high SP rates (0.816–0.966). To improve diagnostic accuracy for childhood obesity, further studies may define a cut-off value for childhood obesity specific for a local population and ethnicity by using health-related overfat data.

A Novel Indicator Of Lipid Accumulation Product Associated With Metabolic Syndrome In Chinese Children And Adolescents

BACKGROUND

The lipid accumulation product (LAP) is a powerful marker for predicting metabolic syndrome (MS) in adults. The present study aimed to propose a novel indicator, the children's lipid accumulation product (CLAP), and to assess its association with MS among Chinese children and adolescents.

METHODS

A total of 683 Chinese children aged 8-15 years were recruited using a stratified cluster sampling method in this cross-sectional study. The presence of MS was defined according to the NCEP-ATP III criteria. The effects of BMI, WHtR and the CLAP for predicting MS were compared using logistic regression models and receiver operating characteristic (ROC) curves.

RESULTS

The prevalence of MS was 5.1% (6.6% and 3.5% among boys and girls, respectively). Overall obesity (based on BMI), abdominal obesity (based on WHtR) and CLAP≥P75 were significantly associated with an increased risk of MS (ORs (95% CIs) were 143.79 (18.78-1101.22), 86.83 (27.19-277.27), 150.75 (20.11-1130.19), respectively). The area under the ROC curve (AUC) for the CLAP was higher than that for BMI and WHtR for predicting MS, with AUC (95% CI) values of 0.944 (0.913-0.975), 0.895 (0.864-0.927), and 0.928 (0.903-0.953), respectively.

CONCLUSION

The children's lipid accumulation product (CLAP) was an effective indicator associated with MS in Chinese children and adolescents and was better than BMI and WHtR for predicting MS.

Longitudinal association between obesity and periodontal diseases among secondary school students in Hong Kong: a prospective cohort study

Background

There is no consensus opinion regarding the association between obesity and periodontal diseases among children and adolescents in the literature.

Methods

A prospective observational cohort study was conducted in a Hong Kong cohort at age 12, 15 and 18. CPI and various obesity indices including BMI, WC, WHR, WHtR, and TRSKF were recorded during each wave of data collection. Information on socioeconomic status and oral health behaviors were collected through self-completed questionnaires.

Results

Two hundred and eighty-two (male: 122 and female: 160) participants completed all three rounds of data collection. Prevalence of overweight/obesity was 27.0, 19.1, and 14.2% at 12, 15, and 18 years, respectively. 19.9% participants had healthy periodontal conditions at age 12. While the percentage dropped to 10.3% at 15 years and 5.7% at 18 years. The proportion of 15-year-old adolescents who brushed teeth more than twice a day was significantly higher among participants belonging to the lower BMI, WC, WHR, and WHtR category (P < 0.05). The fully adjusted model revealed that participants with lower BMI at age 15 had higher probability of having more than 50% index teeth free from periodontal diseases at age 18 (OR: 2.78; 95% CI: 1.16, 6.64; P = 0.022).

Conclusions

Although higher BMI at 15 years was associated with more extensive periodontal inflammation at age 18, this was believed to be an indirect association confounded by the poor oral health care among overweight/obese individuals. Oral health promotions should be directed to improve periodontal conditions of overweight/obese secondary school students.

Assessing the relationship between smoking and abdominal obesity in a National Survey of Adolescents in Brazil

Abdominal obesity is even a stronger risk factor than overall obesity for noncommunicable chronic diseases. We examined the association between smoking and abdominal obesity among adolescents. Analyses were based on 38,813 subjects aged 15-17 years from the Study of Cardiovascular Risks in Adolescents (ERICA), a Brazilian school-based national survey. Abdominal obesity was defined considering waist circumference (WC) percentiles. Statistical analyses, stratified by sex, considered the sample complex design. Poisson regression with robust variance was used to estimate smoker-to-nonsmoker abdominal obesity prevalence ratio (PR), adjusting by sociodemographic and lifestyle variables. Higher prevalence of abdominal obesity was observed among adolescents who consumed >1 cigarettes/day, comparing to nonsmokers: considering WC >80th percentile, adjusted-PR for boys was 1.27 [95%CI:1.05,1.52] and, for girls, 1.09 [95%CI:1.00,1.19]; using the 90th percentile, adjusted-PR were 2.24 [95%CI:1.70,2.94] and 1.27 [95%CI:1.12,1.46], respectively for male and female adolescents. Our findings suggest a positive association between cigarette consumption and the prevalence of abdominal obesity, for both boys and girls. Although other studies had found this association in adults, our study contributes to this discussion by assessing it in adolescents using a nationwide representative sample of medium and large municipalities.

The role of diet in multiple sclerosis: A review

Multiple sclerosis (MS) is a multifactorial, inflammatory, and neurodegenerative disease of the central nervous system, where environmental factors interact with genetic susceptibility. The role of diet on MS has not been comprehensively elucidated; therefore, through an extensive search of relevant literature, this review reports the most significant evidence regarding nutrition as a possible co-factor influencing the inflammatory cascade by acting on both its molecular pathways and gut microbiota. Since nutritional status and dietary habits in MS patients have not been extensively reported, the lack of a scientific-based consensus on dietary recommendation in MS could encourage many patients to experiment alternative dietetic regimens, increasing the risk of malnutrition. This work investigates the health implications of an unbalanced diet in MS, and collects recent findings on nutrients of great interest among MS patients and physicians. The aim of this review is to elucidate the role of an accurate nutritional counseling in MS to move toward a multidisciplinary management of the disease and to encourage future studies demonstrating the role of a healthy diet on the onset and course of MS.

Comparisons of Waist Circumference Measurements at Five Different Anatomical Sites in Chinese Children

This study compared the waist circumference (WC) measurements of Chinese children at different sites to determine the relationship between WC measurements and body fat. WC was measured at five sites in 255 subjects aged 9-19 years: immediately below the lowest rib (WC1), at the narrowest waist (WC2), the midpoint between the lowest rib and the iliac crest (WC3), 1 cm above the umbilicus (WC4), and immediately above the iliac crest (WC5). Body fat mass (FM), body fat percentage (% BF), body fat mass in the trunk (FM in the trunk), and fat percentage in the trunk (% BF in the trunk) were determined by dual-energy X-ray absorptiometry. The WCs were then compared through ANOVA with repeated measurement. The relationship of WC of each site with FM, % BF, FM in the trunk, and % BF in the trunk was examined through partial correlation. The WCs exhibited the following pattern: WC2 < WC1 < WC3 < WC4 < WC5 (p < 0.001) in males and WC2 < WC1 < WC4, WC3 < WC5 (p < 0.001) in females. The measured WCs were strongly correlated with FM, % BF, FM in the trunk, and % BF in the trunk. The WC measurements at five commonly used sites among Chinese children are different from one another. Results indicate that standardizing the anatomic point for the WC measurements is necessary.