Waist circumference measurement site does not affect relationships with visceral adiposity and cardiometabolic risk factors in children

Association between bisphenol A exposure and cardiometabolic outcomes: A longitudinal approach

Increased cardiometabolic risk is associated with abnormalities in blood biomarkers profile and adiposity measurements. Some substances found in the food matrix and the environment, called endocrine-disrupting chemicals, may impair cardiometabolic health in the early and later stages of life. Bisphenol A (BPA) is a food contaminant that migrates from food contact materials and may act as an endocrine disruptor, negatively affecting human health. The present work aims to longitudinally assess the association between BPA exposure and cardiometabolic outcomes, considering data from Portuguese population-based birth cohort Generation XXI. Blood insulin (0.06stdβ; 95 %CI:0.03,0.09) and insulin resistance (0.05stdβ; 95 %CI:0.02,0.08) presented a significant longitudinal association with BPA daily exposure after adjustment for important variables and energy. The same findings were observed for fat mass (0.03stdβ; 95 %CI 0.01,0.06) and waist circumference (0.06stdβ; 95 %CI:0.04,0.08). For z-BMI, a significant cross-sectional (0.03stdβ; 95 %CI:0.01,0.04) and longitudinal (0.02stdβ; 95 %CI:0.00,0.04) association was found. This was the first study assessing the association between BPA exposure and health outcomes from childhood to adolescence. We found an association between BPA exposure and increased blood insulin level, insulin resistance, fat mass percentage, waist circumference and z-BMI. Our results point to the need to reduce exposure to BPA in the early stages of life.

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].

Acculturation and Health Status in the Children's Healthy Living Program in the Pacific Region

Acculturation/enculturation has been found to impact childhood health and obesity status. The objective of this study is to use cross-sectional data to examine the association between proxies of adult/caregiver acculturation/enculturation and child health status (Body Mass Index [BMI], waist circumference [WC], and acanthosis nigricans [AN]) in the U.S.-Affiliated Pacific Islands (USAPI), Alaska, and Hawai'i. Study participants were from the Children's Healthy Living (CHL) Program, an environmental intervention trial and obesity prevalence survey. Anthropometric data from 2-8 year olds and parent/caregiver questionnaires were used in this analysis. The results of this study (n = 4121) saw that those parents/caregivers who identified as traditional had children who were protected against overweight/obesity (OWOB) status and WC > 75th percentile (compared to the integrated culture identity) when adjusted for significant variables from the descriptive analysis. AN did not have a significant association with cultural classification. Future interventions in the USAPI, Alaska, and Hawai'i may want to focus efforts on parents/caregivers who associated with an integrated cultural group as an opportunity to improve health and reduce child OWOB prevalence.

The benefits of nurturant-involved parenting for children's internalizing symptoms and cardiometabolic health in high-risk contexts

Despite evidence that nurturant-involved parenting is linked with children's social, psychological, and physiological development, less is known about the specific contexts in which nurturant-involved parenting is most beneficial for children's mental and physical health. The present study examined how associations between nurturant-involved parenting and children's internalizing symptoms and cardiometabolic risk varied as a function of children's stress and discrimination. Participants included 165 Black and Latinx children (Mage = 11.5 years) and their guardians. Children reported on their ongoing stress, experiences of discrimination, and internalizing symptoms (depression and anxiety). Guardians provided information about their nurturant-involved parenting practices. Children's cardiometabolic risk was assessed as a composite reflecting a high level of systolic or diastolic blood pressure, waist circumference, HbA1c, triglycerides, and low HDL cholesterol. Regression analyses indicated that among youth who reported high levels of stress and discrimination, nurturant-involved parenting was negatively associated with cardiometabolic risk. Although children's stress and discrimination were significantly associated with their internalizing symptoms, neither stress nor discrimination moderated the relation between nurturant-involved parenting and internalizing symptoms. Results highlight the significant role that parents play in shaping children's health, particularly among youth experiencing high levels of stress and discrimination.

Predictive ability of anthropometric indices in identifying metabolic syndrome among US adolescents 10 to 19 years old: Analysis from the National Health and Nutrition Examination Survey 2011 to 2018 data set

OBJECTIVE

The aim of this study was to identify the best anthropometric indices for predicting metabolic syndrome in US adolescents.

METHODS

A cross-sectional study analyzed data of adolescents ages 10 to 19 y using the National Health and Nutrition Examination Survey 2011 to 2018 data. The receiver operating characteristic areas under the curve (AUCs) of waist circumference z score, body roundness index, body mass index, and A Body Shape Index in identifying predicting metabolic syndrome were assessed. Furthermore, sensitivity, specificity, positive predictive value, negative predictive value, and positive and negative likelihood ratios of all anthropometric indices were calculated.

RESULTS

A total of 5496 adolescents were included in the analysis. Waist circumference z score had an AUC of 0.90 (95% CI, 0.89-0.91), sensitivity of 95.0% (95% CI, 89.4-98.1), and specificity of 74.8% (95% CI, 73.6, 76.0). Body roundness index had an AUC of 0.88 (95% CI, 0.87-0.89), sensitivity of 96.7% (95% CI, 91.7-99.1), and specificity of 75.2% (95% CI, 74.1-76.4). Body mass index z score had an AUC of 0.83 (95% CI, 0.81-0.85), sensitivity of 97.5% (95% CI, 92.9-99.5), and specificity of 68.2% (95% CI, 66.9-69.4). A Body Shape Index had an AUC of 0.59 (95% CI, 0.56-0.61), sensitivity of 75.0% (95% CI, 66.3-82.5), and specificity of 50.9% (95% CI, 49.5-52.2).

CONCLUSIONS

Our study found waist circumference z score and body roundness index were the best predictors of predicting metabolic syndrome compared with body mass index z score and A Body Shape Index in both boys and girls. We recommend that future studies develop global cutoff points for these anthropometric indices and examine their performance in a multi-country setting.

Influence of Waist Circumference Measurement Site on Visceral Fat and Metabolic Risk in Youth

Although the rate of childhood obesity seems to have plateaued in recent years, the prevalence of obesity among children and adolescents remains high. Childhood obesity is a major public health concern as overweight and obese youth suffer from many co-morbid conditions once considered exclusive to adults. It is now well demonstrated that abdominal obesity as measured by waist circumference (WC) is an independent risk factor for cardiovascular disease and metabolic dysfunction in youth. Despite the strong associations between WC and cardiometabolic risk factors, there is no consensus regarding the optimal WC measurement sites to assess abdominal obesity and obesity-related health risk in children and adolescents. Currently, the WC measurement site that provides the best reflections of visceral fat and the best correlations with cardiometabolic risk factors is unclear. The purpose of this review is to explore whether WC measurement sites influence the relationships between WC, visceral fat, and cardiometabolic risk factors in children and adolescents.

A comparison of the effects of cinnamon, ginger, and metformin consumption on metabolic health, anthropometric indices, and sexual hormone levels in women with poly cystic ovary syndrome: A randomized double-blinded placebo-controlled clinical trial

BACKGROUND/OBJECTIVES

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder in women that can alter blood glucose, lipid profile and sexual hormonal level. Therefore, the evaluation of potential therapeutic agents in this population is important. The aim of the study was to determine the effects of cinnamon, ginger, and metformin intake on improvement of sex hormones level, metabolic health (lipid profiles, insulin level and fasting blood glucose) and anthropometric indices (weight, body mass index (BMI), etc.) in women with PCOS.

METHODS

A total of 100 women with PCOS were randomly assigned to one of the following four groups: cinnamon (500 mg of cinnamon, 3 × day), ginger (500 mg of ginger, 3 × day), metformin (500 mg of metformin 3 × day) or placebo. However, 17 participants were excluded for various reasons and consequently, 83 participants were considered for analysis. Sexual hormones, anthropometrics, glycemic and lipid markers were evaluated before and after the 8-week intervention.

RESULTS

Weight and BMI decreased significantly in all intervention groups. The consumption of metformin and cinnamon significantly decreased insulin resistance (HOMA-IR) in comparison to the placebo and ginger groups (P < 0.05). Moreover, a significant decrease in FSH (follicle-stimulating hormone) and LH (Luteinizing hormone) levels were observed in the ginger compared to the placebo group. While metformin and cinnamon significantly lowered testosterone levels (P < 0.05), none of the groups experienced a significant change in DHEA (dehydroepiandrosterone).

CONCLUSION

Our findings suggest that in women with PCOS, cinnamon supplementation causes similar reductions in insulin resistance and testosterone level to that of metformin. Ginger supplementation decreased FSH and LH, hormonal effects not seen following metformin consumption. Overall, cinnamon and ginger supplementations may potentially be used as alternative treatment in women with PCOS.

CLINICAL TRIAL REGISTRATION

[https://www.irct.ir/trial/28548], identifier [IRCT20171227038105N1].

The most effective exercise to prevent obesity: A longitudinal study of 33,731 Taiwan biobank participants

Regular physical exercise is recommended to reduce the risk of obesity. However, it remains unclear which activities are more effective in preventing obesity. In this study, five obesity indices and lifestyle factors of 33,731 Taiwan Biobank adults were measured/collected twice with a mean time interval of 4.06 years. A linear mixed effects model was fitted to assess the associations of exercises with obesity indices, in which a random intercept term was used to account for individual differences. The five obesity indices included body mass index (BMI), body fat percentage (BFP), waist circumference (WC), hip circumference (HC), and waist-hip ratio (WHR). Among 23 exercises, jogging and yoga were consistently the most effective choices across all five obesity indices. One more weekly hour to jog was associated with a 0.093 kg/m2 decrease in BMI (p = 4.2E-20), a 0.297% decrease in BFP (p = 3.8E-36), a 0.398 cm decrease in WC (p = 1.6E-21), and a 2.9E-3 decrease in WHR (p = 1.3E-17). One more weekly hour to perform yoga was associated with a 0.225 cm decrease in HC (p = 6.4E-14). Jogging is an exercise for the entire body. Arms swing, waist turn, legs and feet run, and shoulders and abdomen are also involved in this act. By contrast, many yoga poses use muscles around the hips and pelvis, and therefore yoga is the most effective exercise to reduce HC.

The relationship between metabolic syndrome and bone mineral density in adolescents: analysis of the National Health and Nutrition Examination Survey

OBJECTIVES

The purpose of this study was to observe the relationship between metabolic syndrome (MetS) and height (Ht) adjusted Z-scores for areal bone mineral density (aBMD) in adolescents.

METHODS

A retrospective study was conducted on the United States adolescents aged 12-17 years. Data were extracted from the National Health and Nutrition Examination Survey (NHANES) 2011-2012, 2013-2014 and 2015-2016 cycles. Ht adjusted Z-scores for aBMD were calculated.

RESULTS

A total of 969 adolescents (493 boys and 476 girls), aged 14.5 ± 1.7 years were enrolled in this study. After control for age, gender, race, 25-hydroxyvitamin D [25(OH)D], and lean body mass index (LBMI) Z-score, adolescents with MetS had significantly lower levels of total body (less head) aBMD Ht-Z-adjusted Z-score than adolescents with one, two components of MetS and without component of MetS (p<0.05) and significantly lower levels of lumbar spine aBMD Ht-Z-adjusted Z-score than adolescents with one component of MetS and without component of MetS (p<0.05). There were significantly negative associations between total body (less head) aBMD Ht-Z-adjusted Z-score and waist circumference (WC) (β=-0.027, p<0.001, R²=0.057) and homeostasis model assessment insulin resistance (HOMA-IR) (β=-0.225, p<0.001, R²=0.016). There were significantly negative associations between lumbar spine aBMD Ht-Z-adjusted Z-score and WC (β=-0.039, p<0.001, R²=0.058) and HOMA-IR (β=-0.251, p<0.001, R²=0.008).

CONCLUSIONS

The present study demonstrates that MetS may have a negative effect on bone mineral density in adolescents. Abdominal obesity and insulin resistance play a major role on the decline of aBMD in adolescents.

Sex-Heterogeneity on the Association between Dietary Patterns at 4 Years of Age with Adiposity and Cardiometabolic Risk Factors at 10 Years of Age

To evaluate the association of dietary patterns (DP) at 4 years with adiposity and cardiometabolic risk factors at 10 years, considering sex-heterogeneity. This prospective analysis included 3823 children enrolled in the population-based birth cohort, Generation XXI (Porto-Portugal, 2005-2006). Diet at 4 years was assessed by FFQ, with three DP being identified: high in energy-dense foods (EDF), intermediate in snacks (snacking), and healthier (reference). BMI at 10 years was considered as the Z-score according to the WHO. Other adiposity indicators-fat mass percentage (FM%), fat mass index (FMI), and waist-to-height ratio (WHtR)-were converted to z-scores using the sample's sex-specific means and standard deviations, as were the cardiometabolic risk factors (systolic and diastolic blood pressure, lipid profile, and insulin resistance). The associations of DP at 4 years with later adiposity or cardiometabolic factors were estimated by linear regression or by multinomial logistic regression models. In fully adjusted models, the EDF DP was significantly positively associated with the BMI (EDF vs. healthier: β = 0.139; 95% CI: 0.031, 0.246, P-interaction = 0.042) and obesity (OR = 2.68; 95% CI 1.55, 4.63, P-interaction = 0.005) only in girls, among whom, it increased insulin (β = 0.165; 95% CI: 0.020, 0.311) and HOMA-IR (β = 0.159; 95% CI: 0.013, 0.306) at 10 years. An EDF DP at 4 years is associated with later adiposity, insulin, and HOMA-IR in girls.

Associations of five obesity metrics with epigenetic age acceleration: Evidence from 2,474 Taiwan Biobank participants

OBJECTIVE

Obesity is associated with epigenetic age acceleration (EAA), resulting in an increased risk of many age-related disorders. However, most studies have focused on the relationship of EAA with BMI. Whether any other obesity metric is more relevant to EAA remains unknown.

METHODS

Here, the methylation ages of 2,474 Taiwan Biobank (TWB) participants were calculated according to Levine's phenotypic age (PhenoAge) and Lu's GrimAge. Residuals from regressing methylation age on chronological age were used to quantify PhenoEAA and GrimEAA. Five obesity metrics were evaluated, namely BMI, body fat percentage, waist circumference, hip circumference, and waist-hip ratio. Sex-stratified EAA was regressed on each of the five obesity metrics.

RESULTS

For male individuals, an increase of one SD in waist-hip ratio (0.06) was associated with a 0.602-year PhenoEAA (p = 6.3E-6) and a 0.481-year GrimEAA (p = 1.2E-8). For female individuals, every SD increase in BMI (3.7 kg/m² ) was associated with a 0.600-year PhenoEAA (p = 3.3E-5) and a 0.305-year GrimEAA (p = 3.1E-5).

CONCLUSIONS

"Abdominal obesity" and "general obesity" are significantly associated with male and female EAA, respectively. The prevention of abdominal obesity and general obesity is associated with a lower risk of EAA in men and women, respectively.

Evaluation of the relationship between serum ferritin and insulin resistance and visceral adiposity index (VAI) in women with polycystic ovary syndrome

PURPOSE

There is a relationship between polycystic ovary syndrome (PCOS) and adipose tissue dysfunction (ADD), but this relationship is not clear. It has been recently shown that iron accumulation in adipose tissue is among the causes of adipose tissue dysfunction. Data on adipose tissue dysfunction in women with PCOS are insufficient. In this study, we aimed to evaluate the relationship between serum ferritin levels (iron accumulation biomarker) and visceral adiposity index (an indicator of adipose tissue dysfunction).

METHODS

The study is a case-control study. Women with diagnosed PCOS with 2003 Rotterdam Diagnostic Criteria (n = 40) were compared with non-PCOS group (n = 40). In this study, the cholesterol ratios, the homeostatic model evaluation index for insulin resistance (HOMA-IR) and the quantitative insulin sensitivity control index were calculated using biochemical parameters, and the visceral adiposity index (VAI) and the lipid accumulation product (LAP) were calculated using both anthropometric and biochemical parameters. In this study, insulin resistance was evaluated by HOMA-IR and adipose tissue dysfunction was evaluated by VAI index.

RESULTS

According to the results of this study, women with PCOS have a worse metabolic status than women without PCOS. However, this has been shown only in overweight and obese women, not in women with normal weight.

CONCLUSION

As a result, the presence of obesity in women with PCOS exacerbates metabolic status.

LEVEL OF EVIDENCE

Level V, cross-sectional descriptive study.

Population-based waist circumference reference values in Japanese children (0-6 years): comparisons with Dutch, Swedish and Turkish preschool children

BACKGROUND

During 1978-1981 the Japanese Standards Association conducted a national survey to collect 64 distinct body measurements for Japanese children and adults. During 1978-1981, the prevalence of childhood obesity was relatively low yet the population was well nourished in Japanese children. The aim of this study is to construct waist circumference and waist circumference to stature ratio reference centile curves for Japanese preschool children.

METHODS

We utilized 1978-1981 national survey data on body sizes. There are 4937 boys and 4758 girls age 0-6 years for waist circumference measurements. Waist circumference was measured at the level of the umbilicus. Using LMS method, centile curves were constructed for waist circumference and waist circumference to stature ratio. These reference values were compared with those of Dutch, Swedish and Turkish children.

RESULTS

Centile reference curves were made for clinical and epidemiological use. Japanese children had smaller waist circumference centile values as compared to waist circumference measured at the midpoint of the lowest rib cage and the iliac crest of Dutch, Swedish and Turkish children. However, Japanese children had comparable waist circumference to stature ratio centile values to those of Dutch and Turkish children.

CONCLUSIONS

This study presents the first age-, sex-, and ethnicity-specific reference values for waist circumference and waist circumference to stature ratio in Japanese preschool children.

Waist Circumference Is Not Associated with Impaired Fasting Blood Glucose in a Sample of Mexican Children and Teenagers: Results from a State Screening Program

A high waist circumference (WC) is used as a risk factor for impaired fasting blood glucose (IFG) in adults. This association is less studied in children and teenagers. The purpose of this study was to analyze the association between having a high WC and IFG by sex and age in a sample of Mexican children and teenagers. We analyzed the data of 12979 participants aged 5 to 17 years to calculate percentile references for uncorrected WC, corrected for height (WC/HT) and by height squared (WC/HT2) with quantile regression. A subsample of 2309 participants with fasting blood glucose samples (FBG), WC, WC/HT and WC/HT2 values was analyzed with logistic regression. A high WC, WC/HT, and WC/HT2 were considered at the sex- and age-specific 90th percentile from the subsample. The IFG was considered as FBG ≥100 mg/dL. Having a high WC, WC/HT, nor WC/HT2 was not significantly associated with IFG for either sex and age group (all p > 0.05). A high WC, either on its uncorrected or corrected for height values, was not an important assessment for predicting IFG in a sample of Mexican children and teenagers. This study provides percentile reference values specific for sex and age.

10-Year Changes in Adiposity in Cameroon School-Age Children: Evidence for Increasing Central Adiposity and Higher Adiposity Levels in Tallest-for-Age Children

OBJECTIVE

To examine changes in measures of adiposity and determine the prevalence of excess adiposity in relation to height in school children between 2010 and 2020.

METHODS

5-12-year-old urban school-age children participated in two cross-sectional surveys in 2010 (n = 1274) and 2020 (n = 1550). Standard procedures were used for anthropometric measurements. Changes in BMI, waist circumference (WC), and waist-to-height ratio (WHtR) and the corresponding proportions of children with excess adiposity were analyzed and adjusted for design variables (class and school type) and age. Children were classified according to quartiles of height z-score and prevalence of excess adiposity estimated across each quartile.

RESULTS

There was a 2.4% and 3.3% increase in adjusted mean BMI and WC, respectively, between 2010 and 2020. The prevalence of central overweight/obesity (WC) and WHtR ≥ 0.5 increased by 7.3% (X ² = 27.151, p < 0.001) and 5.3% (X ² = 26.117, p < 0.001), respectively, between the two surveys except BMI overweight/obesity. The odds of excess adiposity significantly increased in 2020 for central overweight/obesity (WC) (OR 2.8, 95% CI 2.0-3.6) and WHtR ≥ 0.5 (OR 1.8, 95% CI 1.3-2.4) and not for BMI overweight/obesity (OR 1.3, 95% CI 0.8-1.7). The prevalence of BMI overweight/obesity significantly increased from 33% in 2010 to 51.5% in 2020 in the fourth quartile of height z-score (X ² = 19.198, p < 0.001). Similarly, the prevalence of central overweight/obesity (WC) significantly increased from 23.5% in 2010 to 42.4% in 2020 in the fourth quartile of height z-score (X ² = 18.733, p < 0.001).

CONCLUSION

Central overweight/obesity has increased more than BMI overweight/obesity over the last decade. Children with a higher height-for-age tend to accumulate more adiposity. Objective monitoring of adiposity levels and height of children is needed in future to identify groups for targeted intervention and prevention of chronic diseases.

Physical Activity Levels of Chilean Children in a National School Intervention Programme. A Quasi-Experimental Study

Background. Recess is a great opportunity to interrupt sedentary behaviour and increase moderate-to-vigorous physical activity (MVPA) in schoolchildren. This quasi-experimental study aimed to compare the levels of physical activity (PA) during the school day of children in a school intervention programme vs. those in a control group, and to determine compliance with MVPA recommendations. Methods. A sample of 154 schoolchildren (6–12 years old) was obtained from several schools (70 with the intervention and 84 controls). This programme was structured with a duration of 90 min/session and performed three times/week. PA levels were recorded with triaxial accelerometers during the school day: during recess, during a PA session or physical education session (PE), and during lunchtime. No pre-intervention evaluation was performed. Results. The MVPA of the control group was higher than that of the intervention group during the first recess (p < 0.001). None of the groups complied with the recommendations for steps during the PA or PE sessions. During the PA session, sedentary time was lower and MVPA was higher, in the intervention group than in the control group. Fifty percent of the children from the intervention group complied with the MVPA recommendations, vs. 22.7% of those in the control group. Conclusions. The schoolchildren in the intervention group performed more MVPA than those in the control group. Future interventions could include other periods, such as recess and lunchtime, which are opportunities for improving the MVPA levels of schoolchildren.

Comparison of abdominal visceral adipose tissue measurements in adolescents between magnetic resonance imaging and dual-energy X-ray absorptiometry

Excess abdominal visceral adipose tissue (VAT) is associated with cardiometabolic risk factors in adolescents. VAT is mainly measured using Magnetic Resonance Imaging (MRI), yet dual-energy x-ray absorptiometry (DXA) is more affordable and available. The purpose was to compare adolescent VAT values obtained by MRI and DXA. A sample of 330 adolescents 10-16 years of age were recruited (52.3% female, 58.5% White). Abdominal VAT was measured using a General Electric (GE) Discovery MRI scanner with imaging software. A whole-body DXA (GE iDXA) scan was performed, and software calculated VAT within the android region. Wilcoxon signed-rank t-tests were used to determine differences between VAT values, within sex, race (White, African American, and Other race), and BMI categories (normal weight, overweight, and obese). VAT values from MRI and DXA were significantly correlated (r = 0.78, p < 0.001). Average VAT from MRI (0.54 ± 0.43 kg) was significantly higher than VAT from DXA (0.33 ± 0.39 kg) in the overall sample (p < 0.001) and within all subgroups (p < 0.001). All standardized values between the two measurements fell within ±1.96 standard deviations, and differences between the methods were not associated with level of VAT. In this sample, DXA values were correlated with MRI values, but DXA consistently underestimated VAT compared with MRI.

30-year cross-sectional trends in waist-to-height ratio in Australian school age children; 1985 to 2015

AIM

To report 30-year changes in the proportion of children with abdominal obesity measured by waist-to-height ratio (WHtR) ≥ 0.5.

METHODS

Secondary analysis of WHtR ≥ 0.5 data on Australian children age 7 to 15 years from five national cross-sectional population surveys conducted in 1985, 1995, 2007, 2012 and 2015. Changes in the proportions of children with a WHtR ≥ 0.5 across survey years, by age and sex were assessed using chi-squared tests.

RESULTS

Between 1985 and 2012, the proportion of children with WHtR ≥ 0.5 increased from 8.6% [95%CI: 8.0, 9.2] to 25.1% [95%CI: 23.5, 26.7]. An increase of ~5% each decade was observed between 1985 and 2007, and a 6.6% increase was observed between 2007 and 2012. Overall, there was a non-significant decrease in the proportion of children with WHtR ≥ 0.5 between 2012 (25.1% [95%CI: 23.5, 26.7] and 2015 (23.3% [95%CI: 21.6, 25.2].

CONCLUSION

Abdominal obesity has increased over the last 30 years in Australian children. In 2015, one in five children had WHtR ≥ 0.5, a marker of cardiometabolic risk in children. Our finding highlights the importance of including WHtR as a routine measurement in primary health care and population health surveys. This information is needed to guide policy and practice to manage long-term cardiovascular risk in children.

A prospective study on changes in body composition and fat percentage during the first year of cancer treatment in children

BACKGROUNDS/OBJECTIVES

Cancer treatment may lead to significant body composition changes and affect growth and disease outcomes in pediatric cancer patients. This prospective study aimed to evaluate short- and long-term body compositions changes focused on body fat during the first year of cancer treatment in children.

SUBJECTS/METHODS

A prospective study was conducted in 30 pediatric cancer patients (19 hematologic malignancies and 11 solid tumors) and 30 age- and sex-matched healthy controls. Anthropometric measurements and body composition analysis using whole body dual energy X-ray absorptiometry were performed at baseline and 1, 6, and 12 month(s) of cancer treatment. Kruskal-Wallis tests, Wilcoxon paired t tests, and generalized estimation equation (GEE) were applied for statistical analysis.

RESULTS

At baseline, no differences in weight, height, body mass index, abdominal circumferences, body fat, and fat-free mass were observed between 30 controls and 30 pediatric cancer patients. Total fat mass (P < 0.001) and body fat percentage (P = 0.002) increased significantly during the first month, but no changes were observed from 1 to 12 months; however, no changes in the total mass were observed during the first year of cancer treatment. Meanwhile, the total fat-free mass decreased during the first month (P = 0.008) and recovered between 6 and 12 months of follow-up (P < 0.001). According to GEE analysis, there was a significant upward trend in body fat percentage during the first year, especially the first month, of cancer treatment in children with hematologic malignancies, but not in those with solid tumors.

CONCLUSIONS

Our results indicate that cancer treatment is related to significant body composition changes and rapid body fat gain, particularly during the first month after initiating cancer treatment, in children with hematologic malignancies. Therefore, individualized dietary strategies to prevent excessive fat gain are needed in pediatric cancer patients for better outcomes.

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.

Longitudinal associations of android and gynoid fat mass on cardiovascular disease risk factors in normal weight and overweight boys during puberty

OBJECTIVES

The aim of this longitudinal study was to assess associations between android and gynoid fat distribution and different cardiovascular disease risk factors in normal weight as well as overweight/obese boys during the pubertal period.

METHODS

In total, 146 boys (baseline age 11.9 ±0.6 years) were recruited for a 2-year longitudinal study. Total body fat percentage and android-gynoid fat distribution were measured using DXA. In addition, waist and hip circumference was measured and body mass index (BMI) was calculated. Total cholesterol, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, triglycerides, insulin and glucose were measured, and homeostatic model assessment-insulin resistance (HOMA-IR) was calculated. Tanner stage and physical activity were assessed as covariates.

RESULTS

Overweight subjects had worse values for most of the measured blood parameters (P <0.05). Higher android, gynoid fat mass (FM), and android/gynoid FM ratio were longitudinally associated with higher insulin and HOMA-IR values in both normal weight and overweight boys (P <0.05). In addition, higher android FM and gynoid FM were associated with worse values in HDL cholesterol, LDL cholesterol, and triglycerides in overweight boys (P <0.05).

CONCLUSIONS

Our results suggest that higher android as well as gynoid fat have a strong impact on cardiovascular disease risk factors in both normal weight and overweight boys during the pubertal period. It can be suggested that measurement of fat distribution as android and gynoid fat is important for the assessment of the development or burden of metabolic diseases in boys with different weight statuses.

Less Waste on Waist Measurements: Determination of Optimal Waist Circumference Measurement Site to Predict Visceral Adipose Tissue in Postmenopausal Women with Obesity

With obesity being a leading cause of preventable death, it is vital to understand how best to identify individuals with greater risk of metabolic disease, especially those with high visceral adipose tissue (VAT). This study aimed to determine whether three commonly used waist circumference (WC) measurement sites could provide accurate estimations of VAT, as determined by magnetic resonance imaging (MRI), which is a gold standard for measuring VAT, in postmenopausal women with obesity. VAT volume was measured by MRI of the total abdomen in 97 women aged 57.7 ± 0.4 years (mean ± SEM), mean body mass index 34.5 ± 0.2 kg/m². WC was measured at the midpoint between the lowest rib and the iliac crest (WC_mid), the narrowest point of the torso (WC_narrow), and at the level of the umbilicus (WC_umbilicus). WC differed significantly according to measurement site, with WC_narrow (102.1 ± 0.7 cm) < WC_mid (108.3 ± 0.7 cm) < WC_umbilicus (115.7 ± 0.8 cm) (p < 0.001). WC_mid, WC_narrow and WC_umbilicus were all significantly correlated with VAT, as measured by MRI (r = 0.581, 0.563 and 0.390, respectively; p < 0.001 for all), but the relationships between WC_mid or WC_narrow and VAT determined by MRI were stronger than for WC_umbilicus. Measurement of either WC_mid or WC_narrow provides valid estimates of VAT in postmenopausal women with obesity, with WC_narrow being favoured in light of its greater ease and speed of measurement in this population.

Association between dietary patterns and adiposity from 4 to 7 years of age

OBJECTIVE

The present study aimed to evaluate the association of 4-year-old children's dietary patterns with adiposity at 7 years, according to child's sex, using a conceptual model.

DESIGN

Prospective cohort study. Diet was assessed using an FFQ. Age- and sex-specific BMI standard deviation scores (Z-scores) were defined according to the WHO. Fat mass percentage (FM%), fat mass index (FMI) and waist-to-height ratio (WHtR) were also considered, converted into Z-scores using sex-specific means and standard deviations of the current sample. Dietary patterns were identified by latent class analysis and their association with adiposity was estimated by linear regression models.

SETTING

Population-based birth cohort Generation XXI (Porto, Portugal, 2005-2006).

SUBJECTS

Children (n 3473) evaluated at both 4 and 7 years of age.

RESULTS

Three dietary patterns were identified: high in energy-dense foods (EDF); low in foods typically consumed at main meals and intermediate in snacks (Snacking); and higher in vegetables and fish and lower in EDF (Healthier, reference). The EDF dietary pattern at 4 years of age was positively associated with later BMI only in girls (β=0·075, 95 % CI 0·009, 0·140, P-interaction=0·046). The EDF dietary pattern was also associated with other adiposity indicators only in girls (FMI: β=0·071, 95 % CI 0·000, 0·142; WHtR: β=0·094, 95 % CI 0·023, 0·164). Snacking was not significantly associated with any marker of adiposity in either girls or boys.

CONCLUSIONS

Although dietary patterns and adiposity persisted across the two ages in both sexes, EDF at 4 years of age increased adiposity at 7 years of age only in girls.

Intra-abdominal and subcutaneous abdominal fat as predictors of cardiometabolic risk in a sample of Mexican children

BACKGROUND/OBJECTIVE

Few studies in Latin American paediatric populations have differentiated fat deposits in specific areas, such as intra-abdominal fat (IAF) and subcutaneous abdominal fat (SAF). Research in diverse populations is needed, as patterns of fat accumulation vary by ethnicity. The aim of this study was to determine whether IAF and/or SAF are related to cardiometabolic risk factors, independent of total body fat (TBF), in a group of Mexican schoolchildren.

SUBJECTS/METHODS

A cross-sectional study was conducted in Mexico City with 94 children aged between 5 and 11 years. IAF and SAF were assessed by magnetic resonance using two different estimation methods: (a) at the midpoint of lumbar vertebras 4 and 5 (L4-L5) and (b) the sum of the areas of four slices (L1-L2, L2-L3, L3-L4 and L4-L5, which will be referred to as 'total' IAF and SAF). TBF was measured by dual-energy X-ray absorptiometry. The following cardiometabolic risk factors were assessed: total cholesterol, low-density lipoprotein-cholesterol, triglycerides, glucose, insulin, high-density lipoprotein-cholesterol, blood pressure, insulin resistance, number of risk factors and metabolic syndrome score.

RESULTS

After adjusting for sex, age and TBF, total SAF was related to the number of cardiometabolic risk factors and metabolic syndrome score. Although IAF at L4-L5 was also related to the number of cardiometabolic risk factors, there was evidence of collinearity with TBF.

CONCLUSIONS

In this sample of Mexican schoolchildren, TBF and SAF, but not IAF, were associated with higher cardiometabolic risk.

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.

Índice de massa corpórea e perímetro da cintura são bons indicadores para classificação do estado nutricional de crianças

Resumo O estudo objetivou investigar a relação do índice de massa corpórea (IMC), do perímetro da cintura (PC) e da razão cintura/estatura (RCE) com a soma de dobras cutâneas em crianças de 7-10 anos de uma escola pública de São Paulo (SP). Foram tomadas as medidas estatura, peso, PC e dobras tricipital, bicipital, subescapular e suprailíaca, e calculados a soma de dobras cutâneas, o IMC e a RCE. Para a comparação de métodos utilizou-se a estratégia de Bland e Altman com valores transformados em z. Pela análise dos limites de concordância e seus respectivos intervalos de confiança, encontrou-se evidência de boa concordância, principalmente entre IMC e PC com a soma de dobras cutâneas, observando-se estreitos limites de concordância e diferenças menores que 1 desvio-padrão (dp). A RCE apresentou limites de concordância de amplitude moderada, de -1,02 a +0,64 dp (meninos) e -0,74 a +1,12 dp (meninas), e seu desempenho não foi melhor que o do PC isolado, cujos limites de concordância inferior e superior foram de -0,91 a +0,58 dp (meninos) e de -0,56 a +0,89 dp (meninas). Os resultados apoiam o uso de indicadores antropométricos para classificação do estado nutricional, especialmente IMC e PC, considerando que ambos são semelhantes ao classificar crianças segundo a gordura corporal e apresentam vantagens como facilidade de obtenção e baixo custo.

Association between a school-based intervention and adiposity outcomes in adolescents: The Italian "EAT" project

OBJECTIVE

To evaluate whether a school-based multicomponent educational program could improve adiposity measures in middle-school adolescents.

METHODS

A non-randomized controlled pilot study was conducted in six state middle schools (487 adolescents, 11-15 years) in townships in an urban area around Milan, three schools (n = 262 adolescents) being assigned to the intervention group and three schools (n = 225 adolescents) to the control group. The two-school-year intervention included changes in the school environment (alternative healthy vending machines, educational posters) and individual reinforcement tools (school lessons, textbook, text messages, pedometers, re-usable water bottles). The main outcome measure was change in BMI z-score. The secondary outcomes were changes in waist-to-height ratio (WHtR) and behavioral habits.

RESULTS

The intervention was associated with a significant difference in BMI z-score (-0.18 ± 0.03, P<0.01) and in WHtR (-0.04 ± 0.002, P < 0.001), after controlling for baseline covariates. Subgroup analysis showed the maximum association between the intervention and the difference in BMI z-score for girls with overweight/obesity. Physical activity increased and consumption of sugar-sweetened beverages and high-energy snacks decreased in adolescents after the intervention.

CONCLUSIONS

A school-based multicomponent intervention conducted at both environmental and individual levels may be effective for reducing adiposity measures mainly in adolescents with overweight/obesity.

The EPIC Kids Study: a randomized family-focused YMCA-based intervention to prevent type 2 diabetes in at-risk youth

Background

It is well established that behavioral lifestyle interventions resulting in modest weight reduction in adults can prevent or delay type 2 diabetes mellitus; however in children, successful weight management interventions are rarely found outside of controlled clinical settings. The lack of effective community-based programs is a barrier to reducing obesity prevalence and diabetes risk in children. The objective of our study is to develop and test a group-randomized family-centered community-based type 2 diabetes prevention intervention targeting at-risk children, 9- to 12-years-old.

Methods/Design

Using participatory methods, the adult-focused YMCA Diabetes Prevention Program was adapted for families, creating a novel lifestyle behavior change program focused on healthy eating, physical activity, and a supportive home environment. The program will be tested in sixty 9- to 12-year-old children at risk of diabetes and sixty parents over 12 consecutive weeks with two intervention formats randomized by location: a face-to-face instructor-led program, or a hybrid program with alternating face-to-face and mobile technology-delivered content. Anthropometric, behavioral, psychosocial and physiological outcomes will be assessed at baseline, post-intervention (12 weeks), and follow-up (24 weeks). Secondary outcomes are participant acceptability, feasibility, and adherence. The RE-AIM framework (reach, efficacy, adoption, implementation, and maintenance) will guide intervention implementation and evaluation. Changes at 12 weeks will be assessed using a paired t-test combining both delivery formats. Exploratory models using linear regression analysis will estimate the magnitude of the difference between the face-to-face and hybrid format. The sample size of 60 children, informed by a previous YMCA intervention in which −4.3 % change in overweight (SE = 1.1) was observed over 6 months, will give us 80 % power to detect an effect size of this magnitude, assuming a one-sided test at alpha = 0.05.

Discussion

The proposed study capitalizes on a partnership with the YMCA, a popular and widespread community organization, and uses mobile technologies to extend program reach while potentially reducing burden associated with weekly attendance. The long-term goal is to create a scalable, replicable, and sustainable pediatric “diabesity” prevention program that overcomes existing barriers to the translation of efficacious interventions into effective community programs.

Trial registration

ClinicalTrials.gov, NCT02421198 on April 15, 2015

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.

Metformin treatment to reduce central adiposity after prenatal growth restraint: a placebo-controlled pilot study in prepubertal children

BACKGROUND

Children born small-for-gestational-age (SGA) who experience rapid postnatal catch-up in weight are at risk for central adiposity and hyperinsulinemia.

OBJECTIVES

To study the effects of prepubertal metformin intervention over 24 months on the body composition and endocrine-metabolic profile of catch-up SGA children.

METHODS

Double-blind, placebo-controlled, pilot study including 23 post-catch-up non-obese prepubertal SGA children [age, 7.7 yr; body mass index standard deviation score (BMI SDS) >50th and <97th centile for age] with increased visceral fat [by magnetic resonance imaging (MRI) and insulin-like growth factor-I (IGF-I) both p > 75th for age]. Patients were randomized to receive either placebo or metformin (425 mg/d) for 24 months. Clinical, biochemical [IGF-I, glucose, insulin, lipids, androgens, sex-hormone-binding globulin (SHBG) and high-molecular-weight (HMW)-adiponectin] and imaging [body composition (absorptiometry and MRI; carotid intima-media thickness (ultrasonography)] variables were assessed at baseline, and at 6, 12, and 24 months.

RESULTS

After 24 months, metformin-treated children were leaner, had higher SHBG levels, and less total and abdominal fat than placebo-treated children (all p ≤ 0.05). Longitudinal analyses showed that metformin had a significant effect on anthropometric (weight, BMI, and waist) and biochemical variables [glucose, homeostasis model assessment-insulin resistance (HOMA-IR), and triglycerides] (all p ≤ 0.05); and in total and abdominal fat (p = 0.01 and p = 0.02).

CONCLUSIONS

Prepubertal intervention with metformin reduces central adiposity and improves insulin sensitivity in non-obese catch-up SGA children.

Waist:height ratio, waist circumference and metabolic syndrome abnormalities in Colombian schooled adolescents: a multivariate analysis considering located adiposity

Very few large studies in Latin America have evaluated the association between waist:height ratio (W-HtR) and cardiometabolic risk in children and adolescents. Further, multivariable analyses verifying the independence of located subcutaneous fat have not been conducted so far. The aim of this study was to evaluate the associations of W-HtR and waist circumference (WC) with metabolic syndrome abnormalities and high LDL-cholesterol levels in schooled adolescents before and after adjusting for trunk skinfolds and BMI. The sample consisted of 831 boys and 841 girls aged 10–17 years. Biochemical, blood pressure and anthropometrical variables were measured. Age- and sex-specific quartiles of W-HtR and WC were used in Poisson regression models to evaluate the associations. High WC values (highest quartilev. quartiles 1–3) were associated with high TAG levels in both sexes (prevalence ratio, boys: 2·57 (95 % CI 1·91, 3·44); girls: 1·92 (95 % CI 1·49, 2·47);P<0·05), and with high blood pressure specifically in female adolescents (3·07 (95 % CI 1·58, 5·98);P<0·05), independently of trunk skinfolds or BMI (P<0·05). Associations of high WC with high fasting glucose (boys), low HDL-cholesterol and having at least two abnormalities did not remain significant in most of the adjustments for trunk skinfolds or BMI (P>0·05). High W-HtR (highest quartilev. quartiles 1–3) was only independently associated with high TAG in female adolescents (1·99 (95 % CI 1·55, 2·56);P<0·05). In conclusion, WC showed better association with cardiometabolic risk than W-HtR in the children of this study. This observation does not support W-HtR as a relevant adiposity marker for cardiovascular and metabolic risk in adolescence.

Visceral adipose tissue measured by DXA correlates with measurement by CT and is associated with cardiometabolic risk factors in children

BACKGROUND

Visceral adipose tissue (VAT) generally demonstrates a stronger relationship with cardiometabolic risk factors than total body fat or subcutaneous adipose tissue.

OBJECTIVES

The purpose of this study was to compare VAT estimated in children by total volume dual-energy X-ray absorptiometry (DXA) with a gold standard measurement, single slice (L4-L5) computed tomography (CT).

METHODS

A total of 329 (152 females, 177 males) children ages 6-18 years (mean age 12.3 ± 3.6) and with average body mass index percentile of 54.9% (3-99%) had their VAT estimated by both CT and DXA. Linear association between methods was measured using Pearson's correlation. Multiple linear regressions compared the associations between cardiometabolic risk factors and both CT-VAT and DXA-VAT, respectively.

RESULTS

In children, DXA-VAT was correlated significantly with CT-VAT, with a stronger relationship in overweight and obese children. Multiple regression analysis showed that both estimates of VAT were significantly associated with lipids and insulin sensitivity, measured by euglycaemic-hyperinsulinaemic clamp. Additionally, DXA-VAT was associated with diastolic blood pressure, homeostasis model of insulin resistance and fasting insulin, but CT-VAT was not.

CONCLUSION

In children, total volume DXA-VAT and single slice CT-VAT are significantly correlated and each demonstrates similar associations with cardiometabolic risk factors. This suggests that DXA is a useful and valid method for estimation of VAT in children.

[Anthropometric indices to identify metabolic syndrome and hypertriglyceridemic waist phenotype: a comparison between the three stages of adolescence]

OBJECTIVE:

To determine the prevalence of metabolic syndrome (MS) and the hypertriglyceridemic waist phenotype (HW) in a representative adolescent sample; as well as to establish which anthropometric indicator better identifies MS and HW, according to gender and adolescent age.

METHODS:

This cross sectional study had the participation of 800 adolescents (414 girls) from 10-19 years old. Anthropometric indicators (body mass index, waist perimeter, waist/stature ratio, waist/hip ratio, and central/peripheral skinfolds) were determined by standard protocols. For diagnosis of MS, the criteria proposed by de Ferranti et al. (2004) were used. HW was defined by the simultaneous presence of increased waist perimeter (>75th percentile for age and sex) and high triglycerides (>100 mg/dL). The ability of anthropometric indicators was evaluated by Receiver Operating Characteristic curve.

RESULTS:

The prevalence of MS was identical to HW (6.4%), without differences between genders and the adolescence phases. The waist perimeter showed higher area under the curve for the diagnosis of MS, except for boys with 17-19 years old, for whom the waist/stature ratio exhibited better performance. For diagnosing HW, waist perimeter also showed higher area under the curve, except for boys in initial and final phases, in which the waist/stature ratio obtained larger area under the curve. The central/peripheral skinfolds had the lowest area under the curve for the presence of both MS and HW phenotype.

CONCLUSIONS:

The waist perimeter and the waist/stature showed a better performance to identify MS and HW in both genders and in all three phases of adolescence.

Centile curves and reference values for height, body mass, body mass index and waist circumference of Peruvian children and adolescents

This study aimed to provide height, body mass, BMI and waist circumference (WC) growth centile charts for school-children, aged 4-17 years, from central Peru, and to compare Peruvian data with North-American and Argentinean references. The sample consisted of 8753 children and adolescents (4130 boys and 4623 girls) aged 4 to 17 years, from four Peruvian cities: Barranco, La Merced, San Ramón and Junín. Height, body mass and WC were measured according to standardized techniques. Centile curves for height, body mass, BMI and WC were obtained separately for boys and girls using the LMS method. Student t-tests were used to compare mean values. Overall boys have higher median heights than girls, and the 50th percentile for body mass increases curvilinearly from 4 years of age onwards. In boys, the BMI and WC 50th percentiles increase linearly and in girls, the increase presents a curvilinear pattern. Peruvian children are shorter, lighter and have higher BMI than their counterparts in the U.S. and Argentina; in contrast, age and sex-specific WC values are lower. Height, body mass and WC of Peruvian children increased with age and variability was higher at older ages. The growth patterns for height, body mass, BMI and WC among Peruvian children were similar to those observed in North-American and Argentinean peers.

In Nonobese Girls, Waist Circumference as a Predictor of Insulin Resistance Is Comparable to MRI Fat Measures and Superior to BMI

OBJECTIVE

The aim of this study was to investigate the degree to which waist circumference (WC), body mass index (BMI), and magnetic resonance imaging (MRI)-measured abdominal fat deposition predict insulin resistance (IR) in nonobese girls of diverse racial and ethnic backgrounds.

METHODS

Fifty-seven nonobese girls (12 African-American, 16 Hispanic White, and 29 non-Hispanic White girls) aged 11-14 years were assessed for WC, MRI hepatic proton density fat fraction, visceral and subcutaneous adipose tissue volume, BMI Z-score, fasting insulin, homeostasis model of assessment (HOMA)-IR, adiponectin, leptin, sex hormone-binding globulin, high-density lipoprotein cholesterol, and triglycerides.

RESULTS

Univariate and multivariate analyses adjusted for race and ethnicity indicated that only WC and visceral adipose tissue volume were independent predictors of fasting insulin and HOMA-IR, while hepatic proton density fat fraction, BMI Z-score, and subcutaneous adipose tissue volume were dependent predictors. Hispanic White girls showed significantly higher mean fasting insulin and HOMA-IR and lower sex hormone-binding globulin than non-Hispanic White girls (p < 0.01).

CONCLUSIONS

In nonobese girls of diverse racial and ethnic backgrounds, WC, particularly when adjusted for race or ethnicity, is an independent predictor of IR comparable to MRI-derived measurements of fat and superior to the BMI Z-score.

High waist circumference is associated with elevated blood pressure in non-Hispanic White but not Hispanic children in a cohort of pre-adolescent children

BACKGROUND

Hispanics comprise the most rapidly growing demographic in the US, but little is known about the cardiometabolic risk factors in Hispanic children. This study examined the association of high waist circumference (WC) and elevated blood pressure by race/ethnicity in a cohort of 9 to 13 year olds in New Haven, CT (n = 824).

METHODS

WC, overweight status and blood pressure were measured in 2009, with follow-up in 2011.

RESULTS

Logistic regression revealed that Hispanic children had increased likelihood of elevated blood pressure at follow-up. High baseline WC was associated with increased likelihood of elevated blood pressure for non-Hispanic White but not Hispanic or non-Hispanic Black pre-adolescents, controlling for baseline age, gender, overweight, and blood pressure.

CONCLUSION

Potential racial/ethnic differences in the association between high WC and elevated blood pressure may impact identification of children at risk for elevated blood pressure, especially among Hispanics.

Relationship of anthropometric indices to abdominal and total body fat in youth: sex and race differences

OBJECTIVE

To determine the influence of sex and race on relationships between anthropometry (body mass index [BMI], waist circumference [WC], waist-to-height ratio [W/Ht]) and adiposity (fat mass [FM], abdominal subcutaneous [SAT] and visceral adipose tissue [VAT]) in African American and white youth.

METHODS

The sample included 382 youth 5-18 years of age. FM and abdominal adiposity were assessed using dual energy X-ray absorptiometry and magnetic resonance imaging. Regression was used to examine sex and race effects in the relationship between independent (BMI, WC, and W/Ht) and dependent (FM, SAT and VAT) variables.

RESULTS

BMI and WC were highly related to adiposity while W/Ht was moderately related. The association of BMI with FM and SAT was independent of sex and race, while the relationships of WC and W/Ht with FM and SAT were influenced by both sex and race. In contrast, the association between BMI and VAT was influenced by sex and race, while the relationships of WC and W/Ht with VAT were not.

CONCLUSIONS

WC and W/Ht have similar relationships with adiposity; however, WC presented stronger relationships. BMI is a predictor of overall adiposity but sex and race play a role in its relationship with VAT.

Whole body fat: content and distribution

Obesity and its co-morbidities, including type II diabetes, insulin resistance and cardiovascular diseases, have become one of the biggest health issues of present times. The impact of obesity goes well beyond the individual and is so far-reaching that, if it continues unabated, it will cause havoc with the economies of most countries. In order to be able to fully understand the relationship between increased adiposity (obesity) and its co-morbidity, it has been necessary to develop proper methodology to accurately and reproducibly determine both body fat content and distribution, including ectopic fat depots. Magnetic Resonance Imaging (MRI) and Spectroscopy (MRS) have recently emerged as the gold-standard for accomplishing this task. Here, we will review the use of different MRI techniques currently being used to determine body fat content and distribution. We also discuss the pros and cons of MRS to determine ectopic fat depots in liver, muscle, pancreas and heart and compare these to emerging MRI techniques currently being put forward to create ectopic fat maps. Finally, we will discuss how MRI/MRS techniques are helping in changing the perception of what is healthy and what is normal and desirable body-fat content and distribution.

Anthropometric indices as measures of body fat assessed by DXA in relation to cardiovascular risk factors in children and adolescents: NHANES 1999-2004

OBJECTIVE

Anthropometrics are commonly used indices of total and central adiposity. No study has compared anthropometric measurements to dual-energy X-ray absorptiometry (DXA) measurements as correlates of cardiovascular risks in a nationally representative sample of youth. We aimed to evaluate the validity of anthropometrics compared to DXA-assessed adiposity in relation to cardiovascular risks in youth aged 8-19 years.

METHODS

Data were from the National Health and Nutrition Examination Survey 1999-2004 (n=7013). We examined the correlations between anthropometric and DXA measures of adiposity (i.e., body mass index (BMI) versus percent fat mass (%FM) and fat mass index, and waist circumference (WC) and waist-to-height ratio (WHtR) versus percent trunk fat mass (%TFM)) with nine cardiovascular risks, stratified by sex and age, or race-ethnicity.

RESULTS

Anthropometric and DXA adiposity measures were significantly correlated with insulin (r: 0.48 to 0.66), C-reactive protein (r: 0.47 to 0.58), triglycerides (r: 0.15 to 0.41), high-density lipoprotein cholesterol (HDL-C, r: -0.44 to -0.22), systolic blood pressure (SBP, r: 0.10 to 0.31), low-density lipoprotein cholesterol (r: 0.09 to 0.30), total cholesterol (TC, r: 0.01 to 0.29) and glucose (r: 0.05 to 0.20). Only in all youth, BMI was more strongly correlated with SBP (0.22 vs. 0.12, P<0.0001) and HDL-C (-0.34 vs. -0.25, P<0.0001) than %FM; WC but not WHtR was more strongly correlated with HDL-C (-0.37 vs. -0.30, P<0.0001) but less strongly associated with TC (0.12 vs. 0.21, P<0.0001) than %TFM.

CONCLUSIONS

DXA adiposity measures do not produce stronger associations with cardiovascular risk factors in youth than BMI or WC.