Predicting body composition from anthropometry in pre-adolescent children

Adiposity and body fat distribution based on skinfold thicknesses and body circumferences in Czech preschool children, secular changes

Background

The long-standing widespread prevalence of obesity includes issues of its evaluation. Nutritional status may be assessed using various tools and methods; among others simple anthropometric measurements are well established. Widely used body mass index (BMI), presents an obstacle of needing to calculate a standard deviation score (SD) for correct use in the child population. As BMI overlooks body composition, it is necessary to evaluate fat and muscle mass with different methods. Established skinfolds and circumferences are used in many variations and equations to accomplish that goal; however, the parameters used in these methods also undergo secular changes. Furthermore, secular changes have been documented in fat mass distribution. The aim of the study is to assess secular changes of skinfolds thickness and body circumferences and evaluate their validity for use in clinical practice and population research.

Methods and sample

Our database consisted of a recent (2016-2022) sample with 594 participants (298 males) and a reference sample (from 1990) with 2,910 participants (1,207 males). Both cohorts comprised Czech preschool children, aged 4.00 to 6.99 years. With standard methodology, anthropometric parameters were obtained for 13 skinfolds and eight circumferences, by trained staff. The equations of Slaughter, Durnin and Deurenberg were correspondingly calculated. Statistical evaluation was conducted in the R programming language, using Welch's test, Cohen's d and the Bland-Altman method.

Results

Our study found significant increases in skinfold thickness on the abdomen, chest I. and forearm, with high clinical relevance (p ≥ 0.01; d = range from 0.20 to 0.70). Contrastingly, apart from the abdominal area, a decrease of circumferences was observed. The body fat percentage estimation equations were tested for bias in the recent sample in the context of bioimpedance analysis with the Bland-Altman method. All equations are suitable for application in clinical use.

Discussion

Documented secular changes in fat mass distribution are only part of a contemporary accelerating trend of obesity prevalence. Our findings support the trend of a decline of circumferences and rise of skinfold thickness in corresponding areas, especially on the limbs, that is evidenced by the trend of latent obesity. The results of the study show the need to complement established diagnostic procedures in childhood obesitology with abdominal and midthigh circumferences and optionally even the maximal circumference of the forearm. These circumferences should always be measured alongside the skinfold thickness of the region. Only in this way can the overall adiposity of an individual with regard to secular changes, including the detection of latent obesity, be objectively evaluated.

Differences in physical activity, sedentary time, and anthropometric variables among children and adolescents: The TUBON project

BACKGROUND

Although physical inactivity may lead to increasing obesity prevalence, research on anthropometric variables changes based on physical activity (PA) in children and adolescents is limited. PA decreases with age, while sedentary behavior increases. The study aimed to examine differences in objectively measured sedentary time, light-intensity physical activity (LPA), and moderate-to-vigorous intensity physical activity (MVPA) between children and adolescents, and the differences in the percentiles of anthropometric variables between physically active and inactive groups according to World Health Organization PA recommendations.

METHODS

A total of 759 participants aged 6-17 years (boys, n=358; girls, n=401) were included in the study. The ActiGraph wGT3x-BT accelerometer was used to measure sedentary time, LPA, and MVPA. Height, weight, waist circumference (WC), triceps skinfold thickness (T-SFT), and medial-calf skinfold thickness (M-SFT) were measured. Body fat percentage (BF%) and body mass index (BMI) were calculated, and the percentiles of anthropometric variables were categorized.

RESULTS

The findings showed that children had less sedentary time and a higher LPA than adolescents for both genders (p<0.05). Children had a higher MVPA than adolescents in girls (p<0.05), but the difference was insignificant in boys (p>0.05). In boys, physically active children were in lower percentiles for T-SFT and BF% than those who did not (p<0.05). In boys, adolescents who were physically inactive were in higher percentiles for BMI, T-SFT, M-SFT, and BF% (p<0.05). In addition, in girls, adolescents who were physically active were in lower percentiles of BMI, M-SFT, and BF%, whereas children who were physically active were in lower percentiles of M-SFT and BF% (p<0.05).

CONCLUSION

Sedentary time increases while PA decreases with age. Children and adolescents who met the WHO PA recommendation had lower percentiles of anthropometric variables, indicating the importance of PA in preventing obesity in these age groups.

Correlations of Anthropometric Measurements With Body Fat Percentage, Fat Mass, and Fat Mass Index in School-Age Children

BACKGROUND

Childhood obesity is a growing public health issue globally, including in India. Anthropometric measures such as body mass index (BMI), waist circumference, and skinfold thickness are commonly used to estimate body fat percentage (BF%), but their correlations with fat mass (FM) and fat mass index (FMI) are less emphasized. This study aimed to explore the relationships between anthropometric measurements and body fat indicators (BF%, FM, and FMI) in school-age children and obtain prediction equations for FM and FMI.

METHODS

This observational cross-sectional study included 250 children (125 boys, 125 girls) aged six to 15 years. Anthropometric measures (BMI, waist circumference, skinfold thickness, etc.) and body composition (via bioelectrical impedance analysis) were collected. Pearson's correlation and multiple regression analyses were used to assess the relationships between anthropometric measurements and body fat indicators and to develop prediction models.

RESULTS

BMI, waist circumference, and triceps skinfold thickness showed strong correlations with FM (r = 0.74, r = 0.73, r = 0.61, respectively) and FMI (Pearson's correlation coefficient (r) = 0.76, r = 0.64, r = 0.57, respectively), while the waist-to-height ratio (r = 0.08) and the arm-to-height ratio (r = 0.12) were poorly correlated with BF%. Our prediction equations for FM and FMI provided better predictive values (R² = 0.75 and 0.69, respectively) than BF% (coefficient of determination (R2) = 0.35).

CONCLUSION

FM and FMI showed stronger correlations with anthropometric measurements than BF%. The waist-to-height ratio and the arm-to-height ratio had small correlations with all three body fat indicators. The prediction equation for FM and FMI outperformed the one for BF%, underscoring their potential utility in assessing adiposity in school-age children.

Leptin resistance in children with in utero exposure to maternal obesity and gestational diabetes

BACKGROUND

Leptin resistance occurs with obesity, but it is unknown if individuals at risk for obesity develop leptin resistance prior to obesity.

OBJECTIVE

Investigate whether leptin resistance is independent of weight status in children at risk for obesity due to intrauterine exposure to maternal obesity or gestational diabetes mellitus (GDM).

METHODS

Mother-child dyads (N = 179) were grouped by maternal pregnancy weight and GDM status: (1) normal weight, no GDM; (2) overweight/obesity, no GDM; (3) overweight/obesity with GDM. Children (4-10 years) were further stratified by current body mass index (BMI) <85th or ≥85th percentile. Leptin resistance of children and mothers was calculated as fasting leptin/fat mass index. Two-way ANOVA was used to assess whether leptin concentrations and leptin resistance differed by current weight status or in utero exposure group, after adjusting for race, sex and Tanner stage.

RESULTS

Children with a BMI ≥85th percentile had more leptin resistance than those with a BMI <85th percentile (p < 0.001), but leptin resistance did not differ by in utero exposure. Similarly, leptin resistance in women was associated with weight status and not prior GDM.

CONCLUSIONS

Results suggest that leptin concentrations are associated with obesity but not risk for obesity based on in utero exposure to maternal obesity or GDM.

Effect of resistance training and high-intensity interval training on metabolic parameters and serum level of Sirtuin1 in postmenopausal women with metabolic syndrome: a randomized controlled trial

BACKGROUND

The present study analyzes the influence of resistance training (RT) and high-intensity interval training (HIIT) on metabolic indices and serum levels of Sirtuin1 (SIRT1) in postmenopausal women who suffer from the metabolic syndrome (MetS).

METHODS

45 postmenopausal women aged 45-65 years with MetS were divided into two intervention groups (RT and HIIT) and one control group, each consisting of 15 people. The RT group performed resistance training for both the upper and lower body, while the HIIT group completed 3 min(min) of high-intensity training at 80-90% of their maximum heart rate (HRmax), followed by moderate walking for 3 min at 55-65% of HRmax. These sessions were conducted for a duration of eight weeks and three times a week, with the samples being collected at the baseline and at the end of the treatment, i.e., week 8.

RESULTS

The results showed that weight, waist circumference, body mass index, fat mass, low-density lipoprotein, triglyceride, cholesterol, fasting blood sugar (FBS), hemoglobin A1c (HbA1C), systolic and diastolic blood pressure decreased, and SIRT1 increased significantly in both training groups. Systolic blood pressure, cholesterol, HbA1C, and FBS decreased more in the HIIT group. Skeletal muscle mass and 1-repetition maximum (1-RM) increased more in the RT group.

CONCLUSIONS

RT and HIIT serve as one of the most effective strategies for therapeutically treating patients with metabolic syndrome.

TRIAL REGISTRATION

IRCT, IRCT20221120056548N1. Registered 23 November 2022 - Retrospectively registered.

Associations Among Physical Activity, Adiposity, and Insulin Resistance in Children Exposed In Utero to Maternal Obesity With and Without Gestational Diabetes

PURPOSE

Investigate whether obesity risk and current weight status are independently associated with physical activity (PA) and whether PA is associated with adiposity and insulin resistance (homeostatic model assessment of insulin resistance) among children with high versus low obesity risk based on in utero exposure to maternal overweight/obesity with gestational diabetes mellitus (GDM; high risk) or without GDM (overweight/obesity; high risk) or maternal normal weight without GDM (low risk).

METHOD

Secondary analysis of data from children born to women with overweight/obesity and GDM, overweight/obesity without GDM, or normal weight without GDM. PA was assessed with accelerometry, percentage of body fat derived from anthropometrics, and homeostatic model assessment of insulin resistance calculated from glucose and insulin.

RESULTS

Among 4- to 10-year-old children (N = 163), analyses of covariance showed that children with a current BMI ≥85th percentile had less vigorous PA than those with BMI <85th percentile, but in utero exposure was not an independent predictor of PA. In linear regression modeling, moderate to vigorous PA was inversely associated with percentage of body fat and homeostatic model assessment of insulin resistance independent of age, Tanner stage, and accelerometer wear time, with stronger associations in high-risk groups.

CONCLUSIONS

Children's PA is related to current weight status but not underlying risk for obesity but may be especially important to reduce obesity and insulin resistance in high-risk children.

Effect of Exercise and Detraining on Signs of Puberty and Selected Inflammatory Markers in Girls with Precocious Puberty

PURPOSE

We examined the effects of aerobic exercise and detraining on adiponectin, resistin, tumor necrosis factor alpha (TNF-α), white blood cell, and pubertal signs (uterine length, ovarian volume, luteinizing hormone [LH], and follicle-stimulating hormone [FSH]) in girls with central precocious puberty (CPP).

METHODS

Thirty girls with CPP (7-9 yr old) were randomly divided into CPP and CPP + Exercise (EX) groups. Fifteen healthy age-matched girls without precocious puberty participated for comparison with CPP. Subjects in the CPP + EX group attended 12 wk of aerobic exercise protocol three sessions a week. In the baseline, after completing the exercise protocol and after 4 wk of detraining, all the parameters were measured. In the CPP and healthy groups, all the parameters were measured in all three stages. To measure adiponectin, resistin, and TNF-α, the ELISA method was used. LH and FSH were measured by electrochemiluminescence immunoassay. White blood cell counts were analyzed by an automated blood cell counter. Repeated-measures ANOVA was used to analyze the results.

RESULTS

CPP girls have lower adiponectin ( P = 0.01) and higher TNF-α levels ( P = 0.001) than healthy girls. In the CPP + EX group, after 12 wk, body weight and fat mass decreased, and adiponectin increased significantly ( P = 0.02). Resistin ( P = 0.02), TNF-α ( P = 0.02), neutrophils ( P = 0.01), and signs of puberty significantly ( P < 0.05) decreased. After detraining, no significant change was observed except TNF-α, which increased significantly ( P = 0.03). In the CPP group, no significant change was observed in any of the parameters; only LH ( P = 0.0001) and uterine length and ovarian volume ( P = 0.003, P = 0.001) decreased after 12 and 16 wk, respectively.

CONCLUSIONS

Aerobic exercise can have a positive effect on the state of inflammation and pubertal signs. Positive effects remain after 4 wk of detraining.

Prediction of fat mass from anthropometry at ages 7 to 9 years in Samoans: a cross-sectional study in the Ola Tuputupua'e cohort

BACKGROUND/OBJECTIVE

With increasing obesity prevalence in children globally, accurate and practical methods for quantifying body fat are critical for effective monitoring and prevention, particularly in high-risk settings. No population is at higher risk of obesity than Pacific Islanders, including children living in the independent nation of Samoa. We developed and validated sex-specific prediction models for fat mass in Samoan children.

SUBJECTS/METHODS

Dual X-ray absorptiometry (DXA) assessments of fat mass and weight, height, circumferences, and skinfolds were obtained from 356 children aged 7-9 years old in the Ola Tuputupua'e "Growing Up" study. Sex-specific models were developed from a randomly selected model development sample (n = 118 females, n = 120 males) using generalized linear regressions. In a validation sample (n = 59 females; n = 59 males), Lin's concordance and Bland-Altman limits-of-agreement (LoA) of DXA-derived and predicted fat mass from this study and other published models were examined to assess precision and accuracy.

RESULTS

Models to predict fat mass in kilograms were: e^[(-0.0034355 * Age8 - 0.0059041 * Age9 + 1.660441 * ln (Weight (kg))-0.0087281 * Height (cm) + 0.1393258 * ln[Suprailiac (mm)] - 2.661793)] for females and e^[-0.0409724 * Age8 - 0.0549923 * Age9 + 336.8575 * [Weight (kg)]-2 - 22.34261 * ln (Weight (kg)) [Weight (kg)]-1 + 0.0108696 * Abdominal (cm) + 6.811015 * Subscapular (mm)-2 - 8.642559 * ln (Subscapular (mm)) Subscapular (mm)-2 - 1.663095 * Tricep (mm)-1 + 3.849035]for males, where Age8 = Age9 = 0 for children at age 7 years, Age8 = 1 and Age9 = 0 at 8 years, Age8 = 0 and Age9 = 1 at 9 years. Models showed high predictive ability, with substantial concordance (ρC > 0.96), and agreement between DXA-derived and model-predicted fat mass (LoA female = -0.235, 95% CI:-2.924-2.453; male = -0.202, 95% CI:-1.977-1.572). Only one of four existing models, developed in a non-Samoan sample, accurately predicted fat mass among Samoan children.

CONCLUSIONS

We developed models that predicted fat mass in Samoans aged 7-9 years old with greater precision and accuracy than the majority of existing models that were tested. Monitoring adiposity in children with these models may inform future obesity prevention and interventions.

Breakfast Quality and Insulin Resistance in Spanish Schoolchildren: A Cross-Sectional Study

Background: Breakfast has traditionally been considered one of the most important meals of the day; however, there is little evidence for the influence of breakfast quality and insulin resistance (IR). This study aimed to assess the quality of breakfast in a group of schoolchildren, and its association with IR. Methods: A cross-sectional study with 852 children (8−13 years) was carried out. Fasting plasma glucose, insulin and anthropometric parameters were measured. A three-day dietary record was used to assess their diet and to calculate the Breakfast Quality Index (BQI). The sample was divided into tertiles according to the BQI (tertile 3: better breakfast quality). The homeostatic model was used to assess insulin resistance (HOMA-IR), and IR was defined as HOMA-IR > 3.16. Results: The prevalence of IR was 5.2%. The mean BQI score was 4.50 ± 1.25, and boys had lower scores than girls. Children in the BQI tertile 3 had a better global diet quality. In boys, being in the BQI tertile 3 was associated with a lower risk of IR (OR [95% CI]: 0.10 [0.01−0.77], p < 0.05). Conclusions: A higher-quality breakfast was associated with better overall diet quality and a lower risk of IR, especially in boys.

Influence of malnutrition and body composition on the gross motor function of children with cerebral palsy in Kano, Nigeria: a cross-sectional study

Background

Malnutrition is common among children with cerebral palsy (CWCP); however, its impact on gross motor function (GMF) is not adequately reported. The study evaluated the influence of malnutrition and body composition on GMF.

Methods

In the cross-sectional survey, CWCP were recruited using purposive sampling from three selected secondary and tertiary hospitals in Kano, Nigeria. Sociodemographic variables were recorded on a data capture form. Anthropometric variables were measured using standard procedures. Percent (%) body fat, malnutrition, and GMF were assessed using skinfold thickness, screening tool for the assessment of malnutrition in pediatrics, and GMF classification system (GMFCS), respectively. The data was analyzed with one-way ANOVA, chi-square, and logistic regression using SPSS version 20 at p < 0.05.

Results

The 146 CWCP have mean age of 4.70 ± 2.46 years. About 95 (65.1%) are malnourished. Those with GMFCS V had lower %body fat and higher malnutrition than children with GMFCS II and I, respectively (p < 0.05). Malnutrition has no significant influence on GMF (B = 0.984, OR = 2.676; 95% CI = 0.965–7.423, p > 0.05). %body fat (B = −0.192, OR = 0.826; 95% CI = 0.687–0.992, p < 0.05), type of CP (OR = 12.106; 95% CI = 3.771–38.866, p < 0.005), child’s position in the family (OR = 1.639; 95% CI = 1.162–2.312, p < 0.05), and mothers’ education (B = −2.815, OR = 0.060; 95% CI = 0.012–0.309, p < 0.005) all predicted GMF.

Conclusions

Majority of the CWCP in this study are malnourished. But malnutrition did not however significantly predict GMF, meaning that though malnutrition could impair children’s physical growth and motor development, it however did not have significant influence on their motor function. Hence, CWCP undergoing rehabilitation may not likely experience significant decrease in their motor function due to inadequate nutrition. Decrease in body fat, type of CP, low level of mothers’ education, and child occupying 4th or more position in the family have negative influence on GMF. It was recommended that physiotherapists should routinely assess for malnutrition in CWCP. Prompt nutritional intervention may prevent considerable lose of body fat and augment the gains of physical rehabilitation by providing appropriate nutrition to support muscle growth and the supply of adequate energy for participation in physical exercise. Adequate caregiver education is important for ensuring satisfactory nutrition for CWCP.

Epigenetic Age Acceleration in Mothers and Offspring 4-10 Years after a Pregnancy Complicated by Gestational Diabetes and Obesity

A known association exists between exposure to gestational diabetes mellitus (GDM) and epigenetic age acceleration (EAA) in GDM-exposed offspring compared to those without GDM exposure. This association has not been assessed previously in mothers with pregnancies complicated by GDM. A total of 137 mother-child dyads with an index pregnancy 4−10 years before study enrollment were included. Clinical data and whole blood samples were collected and quantified to obtain DNA methylation (DNAm) estimates using the Illumina MethylEPIC 850K array in mothers and offspring. DNAm age and age acceleration were evaluated using the Horvath and Hannum clocks. Multivariable linear regression models were performed to determine the association between EAA and leptin, high-density lipoprotein cholesterol (HDL-C), fasting glucose, fasting insulin, and HOMA-IR. Mothers with a GDM and non-GDM pregnancy had strong correlations between chronological age and DNAm age (r > 0.70). Offspring of GDM mothers had moderate to strong correlations, whereas offspring of non-GDM mothers had moderate correlations between chronological age and DNAm age. Association analyses revealed a significant association between EAA and fasting insulin in offspring (FDR < 0.05), while HDL-C was the only metabolic marker significantly associated with EAA in mothers (FDR < 0.05). Mothers in the GDM group had a higher predicted epigenetic age and age acceleration than mothers in the non-GDM group. The association between EAA with elevated fasting insulin in offspring and elevated HDL-C in mothers suggests possible biomarkers that can better elucidate the effects of exposure to a GDM pregnancy and future cardiometabolic outcomes.

Comparison of Several Prediction Equations Using Skinfold Thickness for Estimating Percentage Body Fat vs. Body Fat Percentage Determined by BIA in 6-8-Year-Old South African Children: The BC-IT Study

Body composition measurement is useful for assessing percentage body fat (%BF) and medical diagnosis, monitoring disease progression and response to treatment, and is essential in assessing nutritional status, especially in children. However, finding accurate and precise techniques remains a challenge. The study compares %BF determined by bioelectrical impedance analysis (BIA) and calculated from available prediction equations based on skinfolds in young South African children. A cross-sectional study performed on 202 children (83 boys and 119 girls) aged 6-8 years. Height and weight, triceps and subscapular skinfolds were determined according to standard procedures. %BF was determined with BIA and three relevant available equations. SPSS analyzed the data using paired samples tests, linear regression, and Bland-Altman plots. Significant paired mean differences were found for BIA and Slaughter (t₂₀₁ = 33.896, p < 0.001), Wickramasinghe (t₂₀₁ = 4.217, p < 0.001), and Dezenberg (t₂₀₁ = 19.910, p < 0.001). For all of the equations, the standards for evaluating prediction errors (SEE) were above 5. The Bland-Altman plots show relatively large positive and negative deviations from the mean difference lines and trends of systematic under- and over-estimation of %BF across the %BF spectrum. All three equations demonstrated a smaller %BF than the %BF measured by BIA, but the difference was smallest with the Wickramasinghe equation. In comparison, a poor SEE was found in the three %BF predicted equations and %BF derived from BIA. As such, an age-specific %BF equation incorporating criterion methods of deuterium dilution techniques or 'gold-standard' methods is needed to refute these findings. However, in the absence of developed %BF equations or 'gold-standard' methods, the available prediction equations are still desirable.

Association of Healthy Eating Index-2015 and Dietary Approaches to Stop Hypertension Patterns with Insulin Resistance in Schoolchildren

Background: Diet quality patterns are associated with a lower incidence of insulin resistance (IR) in adults. The aim of this study was to investigate the association between two diet quality indices and IR in schoolchildren and to identify the best diet quality index associated with a lower risk of IR. Methods: A total of 854 schoolchildren (8−13 years) were included in a cross-sectional study, who completed a three-day dietary record to assess their diet. Fasting plasma glucose and insulin were also measured, and anthropometric data were collected. Healthy Eating Index-2015 (HEI-2015), Dietary Approaches to Stop Hypertension (DASH), and adjusted DASH (aDASH) were calculated as diet quality indices. The homeostasis model assessment of insulin resistance (HOMA-IR) was used, and IR was defined as HOMA-IR > 3.16. Results: The prevalence of IR was 5.5%, and it was higher in girls. The mean HEI-2015 and DASH scores were 59.3 and 23.4, respectively, and boys scored lower in both indices. In girls, having a HEI-2015 score above the 33rd percentile was associated with a lower risk of IR (odds ratio [95% CI]: 0.43 [0.19−0.96], p = 0.020). Conclusion: Greater adherence to a healthy dietary pattern, as assessed by a higher HEI-2015 score, was associated with a lower risk of IR in schoolchildren, especially in girls.

Mother-child cardiometabolic health 4-10 years after pregnancy complicated by obesity with and without gestational diabetes

Objective

Obesity in pregnancy and gestational diabetes (GDM) increase cardiometabolic disease risk but are difficult to disentangle. This study aimed to test the hypothesis that 4-10 years after a pregnancy complicated by overweight/obesity and GDM (OB-GDM), women and children would have greater adiposity and poorer cardiometabolic health than those with overweight/obesity (OB) or normal weight (NW) and no GDM during the index pregnancy.

Methods

In this cross-sectional study, mother-child dyads were stratified into three groups based on maternal health status during pregnancy (OB-GDM = 67; OB = 76; NW = 76). Weight, height, waist and hip circumferences, and blood pressure were measured, along with fasting glucose, insulin, HbA1c, lipids, adipokines, and cytokines.

Results

Women in the OB and OB-GDM groups had greater current adiposity and poorer cardiometabolic health outcomes than those in the NW group (p < 0.05). After adjusting for current adiposity, women in the OB-GDM group had higher HbA1c, glucose, HOMA-IR and triglycerides than NW and OB groups (p < 0.05). Among children, adiposity was greater in the OB-GDM versus NW group (p < 0.05), but other indices of cardiometabolic health did not differ.

Conclusions

Poor cardiometabolic health in women with prior GDM is independent of current adiposity. Although greater adiposity among children exposed to GDM is evident at 4-10 years, differences in cardiometabolic health may not emerge until later.

Equations based on anthropometric measurements for adipose tissue, body fat, or body density prediction in children and adolescents: a scoping review

PURPOSE

Assessing the body composition of children and adolescents is important to monitor their health status. Anthropometric measurements are feasible and less-expensive than other techniques for body composition assessment. This study aimed to systematically map anthropometric equations to predict adipose tissue, body fat, or density in children and adolescents, and to analyze methodological aspects of the development of anthropometric equations using skinfolds.

METHODS

A scoping review was carried out following the PRISMA-ScR criteria. The search was carried out in eight databases. The methodological structure protocol of this scoping review was retrospectively registered in the Open Science Framework ( https://osf.io/35uhc/ ).

RESULTS

We included 78 reports and 593 anthropometric equations. The samples consisted of healthy individuals, people with different diseases or disabilities, and athletes from different sports. Dual-energy X-ray absorptiometry (DXA) was the reference method most commonly used in developing equations. Triceps and subscapular skinfolds were the anthropometric measurements most frequently used as predictors in the equations. Age, stage of sexual maturation, and peak height velocity were used as complementary variables in the equations.

CONCLUSION

Our scoping review identified equations proposed for children and adolescents with a great diversity of characteristics. In many of the reports, important methodological aspects were not addressed, a factor that may be associated with equation bias.

LEVEL IV

Evidence obtained from multiple time series analysis such as case studies. (NB: dramatic results in uncontrolled trials might also be regarded as this type of evidence).

Lipodystrophy for the Diabetologist-What to Look For

PURPOSE OF REVIEW

Genetic or acquired lipodystrophies are characterized by selective loss of body fat along with predisposition towards metabolic complications of insulin resistance, such as diabetes mellitus, hypertriglyceridemia, hepatic steatosis, polycystic ovarian syndrome, and acanthosis nigricans. In this review, we discuss the various subtypes and when to suspect and how to diagnose lipodystrophy.

RECENT FINDINGS

The four major subtypes are autosomal recessive, congenital generalized lipodystrophy (CGL); acquired generalized lipodystrophy (AGL), mostly an autoimmune disorder; autosomal dominant or recessive familial partial lipodystrophy (FPLD); and acquired partial lipodystrophy (APL), an autoimmune disorder. Diagnosis of lipodystrophy is mainly based upon physical examination findings of loss of body fat and can be supported by body composition analysis by skinfold measurements, dual-energy x-ray absorptiometry, and whole-body magnetic resonance imaging. Confirmatory genetic testing is helpful in the proband and at-risk family members with suspected genetic lipodystrophies. The treatment is directed towards the specific comorbidities and metabolic complications, and there is no treatment to reverse body fat loss. Metreleptin should be considered as the first-line therapy for metabolic complications in patients with generalized lipodystrophy and for prevention of comorbidities in children. Metformin and insulin therapy are the best options for treating hyperglycemia and fibrates and/or fish oil for hypertriglyceridemia. Lipodystrophy should be suspected in lean and muscular subjects presenting with diabetes mellitus, hypertriglyceridemia, non-alcoholic fatty liver disease, polycystic ovarian syndrome, or amenorrhea. Diabetologists should be aware of lipodystrophies and consider genetic varieties as an important subtype of monogenic diabetes.

No sustained effects of an intervention to prevent excessive GWG on offspring fat and lean mass at 54 weeks: Yet a greater head circumference persists

BACKGROUND

LIFT (Lifestyle Intervention for Two) trial found that intervening in women with overweight and obesity through promoting healthy diet and physical activity to control gestational weight gain (GWG) resulted in neonates with greater weight, lean mass and head circumference and similar fat mass at birth. Whether these neonate outcomes are sustained at 1-year was the focus of this investigation.

METHODS

Measures included body composition by PEA POD air displacement plethysmography (ADP) and Echo Infant quantitative magnetic resonance (QMR) and head circumference at birth (n = 169), 14 (n = 136) and 54 weeks (n = 137). Differences in fat and lean mass between lifestyle intervention (LI) and Usual care (UC) groups were examined using ANCOVA adjusting for maternal age and BMI, GWG, offspring sex and age.

RESULTS

Compared to UC, LI infants had similar weight (112 ± 131 g; P = .40), fat mass (14 ± 80 g; P = .86), lean mass (100 ± 63 g; P = .12) at 14 weeks and similar weight (168 ± 183 g; P = .36), fat mass (148 ± 124 g; P = .24), lean mass (117 ± 92 g; P = .21) at 54 weeks. Head circumference was greater in LI at 54 weeks (0.46 ± 2.1 cm P = .03).

CONCLUSIONS

Greater lean mass observed at birth in LI offspring was not sustained at 14 and 54 weeks, whereas the greater head circumference in LI offspring persisted at 54 weeks.

Evaluating body composition in infancy and childhood: A comparison between 4C, QMR, DXA, and ADP

BACKGROUND

Accurate and precise methods to measure of body composition in infancy and childhood are needed.

OBJECTIVES

This study evaluated differences and precision of three methods when compared with the four-compartment (4C) model for estimating fat mass (FM).

METHODS

FM of children (age 14 days to 6 years of age, N = 346) was obtained using quantitative nuclear magnetic resonance (QMR, EchoMRI-AH), air-displacement plethysmography (ADP, PeaPod, less than or equal to 8 kg, BodPod age 6 years or older), and dual-energy X-ray absorptiometry (DXA, Hologic QDR). The 4C model was computed. Correlation, concordance, and Bland-Altman analyses were performed.

RESULTS

In infants, PeaPod had high individual FM accuracy, whereas DXA had high group FM accuracy compared with 4C. In children, DXA had high group and individual FM accuracies compared with 4C. QMR underestimated group FM in infants and children (300 and 510 g, respectively). The instrument FM precision was best for QMR (10 g) followed by BodPod (34 g), PeaPod (38 g), and DXA (45 g).

CONCLUSIONS

In infants, PeaPod was the best method to estimate individual FM whereas DXA was best to estimate group FM. In children, DXA was best to estimate individual and group FM. QMR had the highest instrument precision.

Less physical activity and more varied and disrupted sleep is associated with a less favorable metabolic profile in adolescents

Background

Sleep and physical activity are modifiable behaviors that play an important role in preventing overweight, obesity, and metabolic health problems. Studies of the association between concurrent objective measures of sleep, physical activity, and metabolic risk factors among adolescents are limited.

Objective

The aim of the study was to examine the association between metabolic risk factors and objectively measured school day physical activity and sleep duration, quality, onset, and variability in adolescents.

Materials and methods

We measured one school week of free-living sleep and physical activity with wrist actigraphy in 252 adolescents (146 girls), aged 15.8±0.3 years. Metabolic risk factors included body mass index, waist circumference, total body and trunk fat percentage, resting blood pressure, and fasting glucose and insulin levels. Multiple linear regression adjusted for sex, parental education, and day length was used to assess associations between metabolic risk factors and sleep and activity parameters.

Results

On average, participants went to bed at 00:22±0.88 hours and slept 6.2±0.7 hours/night, with 0.83±0.36 hours of awakenings/night. However, night-to-night variability in sleep duration was considerable (mean ± interquartile range) 0.75±0.55 hours) and bedtime (0.64±0.53 hours) respectively. Neither average sleep duration nor mean bedtime was associated with any metabolic risk factors. However, greater night-to-night variability in sleep duration and bedtime was associated with higher total body and trunk fat percentage, and less physical activity was associated with higher trunk fat percentage and insulin levels.

Conclusion

Greater nightly variation in sleep duration and in bedtime and less physical activity were associated with a less favorable metabolic profile in adolescents. These findings support the idea that, along with an adequate amount of physical activity, a regular sleep schedule is important for the metabolic health of adolescents.

Utility of published skinfold thickness equations for prediction of body composition in very young New Zealand children

Measurement of body composition is increasingly important in research and clinical settings but is difficult in very young children. Bioelectrical impedance analysis (BIA) and air displacement plethysmography (ADP) are well-established but require specialist equipment so are not always feasible. Our aim was to determine if anthropometry and skinfold thickness measurements can be used as a substitute for BIA or ADP for assessing body composition in very young New Zealand children. We used three multi-ethnic cohorts: 217 children at a mean age of 24·2 months with skinfold and BIA measurements; seventy-nine infants at a mean age of 20·9 weeks and seventy-three infants at a mean age of 16·2 weeks, both with skinfold and ADP measurements. We used Bland-Altman plots to compare fat and fat-free mass calculated using all potentially relevant equations with measurements using BIA or ADP. We also calculated the proportion of children in the same tertile for measured fat or fat-free mass and tertiles (i) calculated using each equation, (ii) each absolute skinfold, and (iii) sum of skinfold thicknesses. We found that even for the best equation for each cohort, the 95 % limits of agreement with standard measures were wide (25-200 % of the mean) and the proportion of children whose standard measures fell in the same tertile as the skinfold estimates was ≤69 %. We conclude that none of the available published skinfold thickness equations provides good prediction of body composition in multi-ethnic cohorts of very young New Zealand children with different birth history and growth patterns.

The role of age, sex, anthropometry, and body composition as determinants of physical fitness in nonobese children aged 6-12

Purpose

The determinants of physical fitness in children have been given limited attention. In particular, the relative role of chronological age, sex, anthropometry, and body composition in physical fitness of children has been barely investigated. This cross-sectional study investigated determinants of physical fitness using a set of predictive variables including, in addition to chronological age and sex, a large panel of anthropometric measurements as well as body composition. The study was carried out in a convenience sample of children aged 6–12 participating in a summer camp.

Methods

One-hundred-ninety-three children (128 males) fulfilled all requirements and entered analysis. Health-related physical fitness components (speed, muscular power and balance) were explored by means of field tests, namely the 30-m dash test for running speed, the standing long jump and the seated chest pass test for lower limbs and upper body muscular power, respectively, and the flamingo balance test for static balance. Determinants of physical fitness were investigated by regression analysis using chronological age, sex, anthropometry, and body composition in a hierarchical approach. To minimize the expected effect of collinearity in predictor variables, an original statistical approach using Random Forests analysis was adopted.

Results

Age predicted 45.2%, 43.6%, 35.6% and 25.6%; and sex 9.5%, 10.7%, 6.3% and 2.0% of variance in the 30-m dash, seated chest pass, standing long jump, and flamingo balance test, respectively. Anthropometry and body composition explained a limited or no percentage of variance. The adjusted R² (root mean square error) was 0.61 (0.31 s), 0.45 (0.32 m), 0.58 (0.15 m) and 0.41 (0.75 logs) for the 30-m dash, seated chest pass, standing long jump, and flamingo balance test, respectively making these models useful when physical fitness tests are not feasible.

Conclusions

We highlighted the respective role of chronological age, sex, anthropometry, and body composition in physical fitness of children in the wide age range 6–12 years. Data confirm and expand on previous literature by showing with a strictly conservative statistical approach that chronological age is a main determinant of physical fitness of both boys and girls, sex playing a limited role. The role of anthropometry was even less important, and no role was found for body composition. These findings should be considered when planning/implementing motor development or physical education programs.

Cardiometabolic evaluation of small for gestational age children: protective effect of breast milk

Introduction

Introduction: human growth is the result of an interaction between genetic, hormonal, nutritional, and environmental factors. It is not yet fully understood what is predominant and decisive in determining an individual's weight and height. Objective: the aim of this study was to evaluate the cardiometabolic profile of exclusively breastfed children born small for gestational age (SGA). Methods: this is a prospective cohort study of children born at term who were classified as SGA, and as appropiate for gestational age (AGA), who were followed up to pre-school age. Anthropometric measures and body composition parameters were obtained. Breastfeeding duration was calculated in days, and achievement of catch up of weight was considered an increase in Z-score ≥ 0.67. The cardiometabolic profile was evaluated in the first month of life and repeated at pre-school age. At pre-school age, fasting blood glucose, insulin, HOMA-IR, and blood pressure were measured. Results: twenty SGA and 12 AGA children were studied. The mean duration of exclusive breastfeeding (EBF) was 180 days in both groups. Of SGA children, 85 % had recovery anthropometric parameters for age within the first six months, with a speed of weight gain significantly higher than the that of AGAs (p < 0.001). SGAs continued to be thinner and smaller than AGAs at pre-school age. There was no diagnosis of overweight or obesity in the studied sample, and no differences were foun between groups in laboratory tests. Conclusion: these findings suggest that EBF may confer protection until pre-school age in children born SGA, who are considered at higher risk for chronic non-communicable diseases.

Docosahexaenoic and Arachidonic Acid Supplementation of Toddlers Born Preterm Does Not Affect Short-Term Growth or Adiposity

BACKGROUND

Dietary DHA intake among US toddlers is low. Healthy physical growth is an important objective for the clinical care of children born preterm.

OBJECTIVES

The aim of the trial was to examine the effects of supplementing toddlers born preterm with DHA and arachidonic acid (AA) for 180 d on growth and adiposity.

METHODS

Omega Tots, a randomized placebo-controlled trial, was conducted between April 2012 and March 2017. Children born at <35 wk gestation who were 10-16 mo in corrected age were assigned to receive daily oral supplements of DHA and AA (200 mg each, "DHA + AA") or corn oil (placebo) for 180 d. Prespecified secondary outcomes included weight, length, head circumference, mid-upper arm circumference, triceps and subscapular skinfolds, BMI, and their respective z scores, and body fat percentage, which were measured at baseline and trial completion. Mixed-effects regression was used to compare the change in outcomes between the DHA + AA and placebo groups, controlling for baseline values.

RESULTS

Among 377 children included in the analysis (median corrected age = 15.7 mo, 48.3% female), 348 (92.3%) had growth or adiposity data at baseline and trial end. No statistically significant differences between the DHA + AA and placebo groups in growth or adiposity outcomes were observed. For instance, the change in weight-for-age z scores was 0.1 for the DHA + AA group and 0.0 for the placebo group (effect size = 0.01, P = 0.99). However, post-hoc subgroup analyses revealed a statistically significant interaction between treatment group and sex, suggesting somewhat slower linear growth for females assigned to the DHA + AA group compared with the placebo group.

CONCLUSIONS

Among toddlers born preterm, daily supplementation with DHA + AA for 180 d resulted in no short-term differences in growth or adiposity compared with placebo. If DHA supplementation is implemented after the first year of life, it can be expected to have no effect on short-term growth or adiposity. This trial is registered with clinicaltrials.gov as NCT02199808.

The relationship between Cormic Index and uterine contractions' pattern in the active phase of the first stage of labour

Uterine contractions are indicators of labour progress. The relationship between anthropometric indices and types of childbirth has been investigated. One of these indices is referred to as the Cormic Index, which provides an estimation of the sitting height and leg length. This cross-sectional study was performed to determine the relationship between the Cormic Index and the uterine contractions' pattern in the active phase of the first stage of labour. The standing and sitting heights of 150 pregnant women were measured to calculate the Cormic Index. Then, two Cardiotocographic traces were recorded during the 3 to 5 and 6 to 8 centimetres' dilations, by which the uterine contractions' pattern were determined. The mean Cormic Index was 51.84 ± 2.62. The results indicated that the Cormic Index had a positive linear correlation with MTIME (frequency of contractions) in the first monitoring episode and SDTIME (regularity of contractions) in the first and the second monitoring episode, which was significant (p < .05). However, there was no significant correlation between the Cormic Index and F:R ratio (shape of contractions) in both monitoring episodes. With the rise of the mother's Cormic Index, the frequency of contractions in the acceleration phase, and also their regularity in the acceleration phase and the phase of the maximum slope, were decreased during the active phase of labour.IMPACT STATEMENTWhat is already known on this subject? Uterine Contraction as an indicator of labour progress enforces cervical dilation. If uterine activity is analysed through electronic methods, one could assess labour outcome through some patterns of the contractions. Anthropometry provides a quick determination of the body proportions. The Cormic Index provides an estimation of the upper and lower body length. Several studies have investigated the relationship between the anthropometric indices and the types of childbirth. Despite the various approaches available, there is no objective means of precisely distinguishing the fact that whether labour can be successful in effecting vaginal delivery or not and diagnosis of dystocia still relies on the trial of labour.What do the results of this study add? The results of this study add to the growing body of research on the progression of labour that Cormic Index has a positive linear correlation with the frequency of contractions in acceleration phase, and with the regularity of contractions in the acceleration phase and the phase of maximum slope.What are the implications of these findings for clinical practice and/or further research? The results can help professionals to evaluate the progress of labour based on the type of uterine contractions in the latent phase or the early active phase of labour using the Cormic Index.

Regional Body Fat Changes and Metabolic Complications in Children With Dunnigan Lipodystrophy-Causing LMNA Variants

CONTEXT

Familial partial lipodystrophy, Dunnigan variety (FPLD2) is a rare autosomal-dominant disorder due to heterozygous missense lamin A/C (LMNA) mutations. Subjects with FPLD2 gradually lose fat from the upper and lower extremities but gain fat in the face and neck around puberty. However, the precise onset of body fat changes and metabolic complications during childhood remains unknown.

OBJECTIVE

To compare metabolic parameters and regional body fat in children with FPLD2 with the sex- and age-matched controls from the National Health and Nutrition Examination Survey (NHANES) 2005 to 2010.

METHODS

We measured fasting serum triglycerides, glucose, and skinfold thicknesses in all children (aged 1 to 18 years) harboring FPLD2-causing LMNA mutations and determined regional body fat by dual-energy X-ray absorptiometry in those aged ≥8 years.

RESULTS

Thirty-two affected females and 14 males participated. The lower limb fat in all affected females, except one, was below or equal to the first percentile and in two affected males was below the fifth percentile for NHANES. One female subject with FPLD2 followed from age 6 to 16 years revealed marked loss of extremity fat much before thelarche. Serum triglycerides were higher in females with FPLD2 aged 7 to 18 years compared with controls (median 208 vs 70 mg/dL; P < 0.0001) and showed inverse correlation with extremity skinfolds. Serum triglycerides in males with FPLD2 were not significantly different than controls.

CONCLUSIONS

The onset of fat loss from the extremities, especially in girls with FPLD2, occurs well before the onset of puberty. High serum triglycerides are seen in young females with FPLD2 with severe loss of fat from the extremities.

Anthropometric multicompartmental model to predict body composition In Brazilian girls

BACKGROUND

Anthropometric models remain appropriate alternatives to estimate body composition of peripubertal populations. However, these traditional models do not consider other body components that undergo major changes during peripubertal growth spurt, with restrictions to a multicompartimental approach as a quantitative growth. DXA has great potential to determine pediatric body composition in more than one component (3-C), but has limited use in field settings. Thus, the aim of this study was to propose and validate an anthropometric model for simultaneous estimation of lean soft tissue (LST), bone mineral content (BMC) and fat mass (FM) in healthy girls, from a multivariate approach of densitometric technique, as the criterion method.

METHODS

A sample of 84 Brazilian girls (7-17 years) was defined by chronological age and maturity offset. Whole total and regional DXA body scan were performed and, the components were defined (LST, BMC and FM) and considered as dependent variables. Twenty-one anthropometric measures were recorded as independent variables. From a multivariate regression, an anthropometric multicompartmental model was obtained.

RESULTS

It was possible to predict DXA body components with only four predictive measurements: body weight (BW); supra-iliac skinfold (SiSk); horizontal abdominal skinfold (HaSk) and contracted arm circumference (CaCi) with high coefficients of determination and low estimation errors (LST = 0.6662657 BW - 0. 2157279 SiSk - 0.2069373 HaSk + 0.3411678 CaCi - 1.8504187; BMC = 0.0222185 BW - 0.1001097 SiSk - 0.0064539 HaSk - 0.0084785 CaCi + 0.3733974 and FM = 0.3645630 BW + 0.1000325 SiSk - 0.2888978 HaSk - 0.4752146 CaCi + 2.8461916). The cross-validation was confirmed through the sum of squares of residuals (PRESS) method, presenting accurate coefficients (Q2PRESS from 0.81 to 0.93) and reduced error reliability (SPRESS from 0.01 to 0.30).

CONCLUSIONS

When sophisticated instruments are not available, this model provides valid estimates of multicompartmental body composition of girls in healthy Brazilian pediatric populations.

Parent and child care provider partnerships: Protocol for the Healthy Me, Healthy We (HMHW) cluster randomized control trial

BACKGROUND

Formation of diet and physical activity habits begins during early childhood. However, many preschool-aged children in the United States do not achieve recommendations for a nutritious diet or active lifestyle. Two important spheres of influence, home and child care, could ensure that children receive consistent health messages. Innovative approaches that engage both parents and child care providers in a substantial way are needed. Social marketing, a promising approach for health promotion targeting children, uses principles that recognize the need to engage multiple stakeholders and to emphasize benefits and overcome barriers associated with behavior change. Yet, application of social marketing principles in interventions for preschool-age children is limited.

METHODS

Healthy Me, Healthy We (HMHW) is 2-arm, cluster randomized controlled trial to evaluate the effect of a 8-month social marketing campaign on the diet and physical activity behaviors of preschool children (3-4years old), their parents, and child care providers. The campaign is delivered by the child care center and includes branded classroom and at-home activities and materials. Primary outcomes are children's diet quality (assessed with Healthy Eating Index scores) and minutes of non-sedentary activity (measured via accelerometers). Secondary outcomes assess children's body mass index, nutrition and physical activity practices at the child care center and at home, and health behaviors of child care providers and parents.

CONCLUSION

HMHW is an innovative approach to promoting healthy eating and physical activity in preschool children. The campaign targets children during a key developmental period and leverages a partnership between providers and parents to affect behavior change.

Equations based on anthropometry to predict body fat measured by absorptiometry in schoolchildren and adolescents

OBJECTIVE

To develop and validate equations to estimate the percentage of body fat of children and adolescents from Mexico using anthropometric measurements.

METHODS

A cross-sectional study was carried out with 601 children and adolescents from Mexico aged 5-19 years. The participants were randomly divided into the following two groups: the development sample (n=398) and the validation sample (n=203). The validity of previously published equations (e.g., Slaughter) was also assessed. The percentage of body fat was estimated by dual-energy X-ray absorptiometry. The anthropometric measurements included height, sitting height, weight, waist and arm circumferences, skinfolds (triceps, biceps, subscapular, supra-iliac, and calf), and elbow and bitrochanteric breadth. Linear regression models were estimated with the percentage of body fat as the dependent variable and the anthropometric measurements as the independent variables.

RESULTS

Equations were created based on combinations of six to nine anthropometric variables and had coefficients of determination (r²) equal to or higher than 92.4% for boys and 85.8% for girls. In the validation sample, the developed equations had high r² values (≥85.6% in boys and ≥78.1% in girls) in all age groups, low standard errors (SE≤3.05% in boys and ≤3.52% in girls), and the intercepts were not different from the origin (p>0.050). Using the previously published equations, the coefficients of determination were lower, and/or the intercepts were different from the origin.

CONCLUSIONS

The equations developed in this study can be used to assess the percentage of body fat of Mexican schoolchildren and adolescents, as they demonstrate greater validity and lower error compared with previously published equations.

Neck Circumference to Assess Obesity in Preschool Children

OBJECTIVE

Limited information is available about the use of neck circumference (NC) to assess obesity in preschool children. This study aims to provide NC percentiles and determine the cut-off levels of NC as a measure to assess obesity in preschool children.

METHODS

The data were obtained from the Anthropometry of Turkish Children aged 0-6 years (ATCA-06) study database. A total of 21 family health centers were chosen and children aged 2-6 years old from all socioeconomic levels were randomly selected from the lists of district midwives; 1766 children (874 male and 892 female; 88.3% of sample size) were included in the study. The smoothed centile curves of NC were constructed by the LMS method. Receiver operating characteristic (ROC) analysis was performed to calculate cut-off points for NC using body mass index ≥95^th percentile.

RESULTS

Mean NC was greater in males than females. Cut-off values for obesity were found to be statistically significant in both genders other than 3 years old boys. The NC percentiles of Turkish preschool children were slightly greater than those of other European preschool children in both genders. This difference disappeared around the adiposity rebound period. The 97th percentile values for Turkish preschool children continue to be greater in both genders.

CONCLUSION

NC may be useful to define obesity in preschool children. Since ethnic and various other factors may have a role in incidence of obesity, local reference data are important in assessment of obesity.

Is questionnaire-based sitting time inaccurate and can it be improved? A cross-sectional investigation using accelerometer-based sitting time

OBJECTIVES

To investigate the differences between a questionnaire-based and accelerometer-based sitting time, and develop a model for improving the accuracy of questionnaire-based sitting time for predicting accelerometer-based sitting time.

METHODS

183 workers in a cross-sectional study reported sitting time per day using a single question during the measurement period, and wore 2 Actigraph GT3X+ accelerometers on the thigh and trunk for 1-4 working days to determine their actual sitting time per day using the validated Acti4 software. Least squares regression models were fitted with questionnaire-based siting time and other self-reported predictors to predict accelerometer-based sitting time.

RESULTS

Questionnaire-based and accelerometer-based average sitting times were ≈272 and ≈476 min/day, respectively. A low Pearson correlation (r=0.32), high mean bias (204.1 min) and wide limits of agreement (549.8 to -139.7 min) between questionnaire-based and accelerometer-based sitting time were found. The prediction model based on questionnaire-based sitting explained 10% of the variance in accelerometer-based sitting time. Inclusion of 9 self-reported predictors in the model increased the explained variance to 41%, with 10% optimism using a resampling bootstrap validation. Based on a split validation analysis, the developed prediction model on ≈75% of the workers (n=132) reduced the mean and the SD of the difference between questionnaire-based and accelerometer-based sitting time by 64% and 42%, respectively, in the remaining 25% of the workers.

CONCLUSIONS

This study indicates that questionnaire-based sitting time has low validity and that a prediction model can be one solution to materially improve the precision of questionnaire-based sitting time.

Comparison of Eight Equations That Predict Percent Body Fat Using Skinfolds in American Youth

BACKGROUND

Skinfolds are often used in equations to predict percent body fat (PBF) in youth. Although there are numerous such equations published, there is limited information to help researchers determine which equation to use for their sample.

METHODS

Using data from the 1999-2006 National Health and Nutrition Examination Surveys (NHANES), we compared eight published equations for prediction of PBF. These published equations all included triceps and/or subscapular skinfold measurements. We examined the PBF equations in a nationally representative sample of American youth that was matched by age, sex, and race/ethnicity to the original equation development population and a full sample of 8- to 18-year-olds. We compared the equation-predicted PBF to the dual-emission X-ray absorptiometry (DXA)-measured PBF. The adjusted R(2), root mean square error (RMSE), and mean signed difference (MSD) were compared. The MSDs were used to examine accuracy and differential bias by age, sex, and race/ethnicity.

RESULTS

When applied to the full range of 8- 18-year-old youth, the R(2) values ranged from 0.495 to 0.738. The MSD between predicted and DXA-measured PBF indicated high average accuracy (MSD between -1.0 and 1.0) for only three equations (Bray subscapular equation and Dezenberg equations [with and without race/ethnicity]). The majority of the equations showed differential bias by sex, race/ethnicity, weight status, or age.

CONCLUSIONS

These findings indicate that investigators should use caution in the selection of an equation to predict PBF in youth given that results may vary systematically in important subgroups.

Anthropometric predictors of body fat in a large population of 9-year-old school-aged children

Objective

To develop and cross‐validate predictive models for percentage body fat (%BF) from anthropometric measurements [including BMI z‐score (zBMI) and calf circumference (CC)] excluding skinfold thickness.

Methods

A descriptive study was carried out in 3,084 pre‐pubertal children. Regression models and neural network were developed with %BF measured by Bioelectrical Impedance Analysis (BIA) as the dependent variables and age, sex and anthropometric measurements as independent predictors.

Results

All %BF grade predictive models presented a good global accuracy (≥91.3%) for obesity discrimination. Both overfat/obese and obese prediction models presented respectively good sensitivity (78.6% and 71.0%), specificity (98.0% and 99.2%) and reliability for positive or negative test results (≥82% and ≥96%). For boys, the order of parameters, by relative weight in the predictive model, was zBMI, height, waist‐circumference‐to‐height‐ratio (WHtR) squared variable (_Q), age, weight, CC_Q and hip circumference (HC)_Q (adjusted r² = 0.847 and RMSE = 2.852); for girls it was zBMI, WHtR_Q, height, age, HC_Q and CC_Q (adjusted r² = 0.872 and RMSE = 2.171).

Conclusion

%BF can be graded and predicted with relative accuracy from anthropometric measurements excluding skinfold thickness. Fitness and cross‐validation results showed that our multivariable regression model performed better in this population than did some previously published models.

Fat-free mass prediction equations for bioelectric impedance analysis compared to dual energy X-ray absorptiometry in obese adolescents: a validation study

Background

In clinical practice, patient friendly methods to assess body composition in obese adolescents are needed. Therefore, the bioelectrical impedance analysis (BIA) related fat-free mass (FFM) prediction equations (FFM-BIA) were evaluated in obese adolescents (age 11–18 years) compared to FFM measured by dual-energy x-ray absorptiometry (FFM-DXA) and a new population specific FFM-BIA equation is developed.

Methods

After an overnight fast, the subjects attended the outpatient clinic. After measuring height and weight, a full body scan by dual-energy x-ray absorptiometry (DXA) and a BIA measurement was performed. Thirteen predictive FFM-BIA equations based on weight, height, age, resistance, reactance and/or impedance were systematically selected and compared to FFM-DXA. Accuracy of FFM-BIA equations was evaluated by the percentage adolescents predicted within 5 % of FFM-DXA measured, the mean percentage difference between predicted and measured values (bias) and the Root Mean Squared prediction Error (RMSE). Multiple linear regression was conducted to develop a new BIA equation.

Results

Validation was based on 103 adolescents (60 % girls), age 14.5 (sd1.7) years, weight 94.1 (sd15.6) kg and FFM-DXA of 56.1 (sd9.8) kg. The percentage accurate estimations varied between equations from 0 to 68 %; bias ranged from −29.3 to +36.3 % and RMSE ranged from 2.8 to 12.4 kg. An alternative prediction equation was developed: FFM = 0.527 * H(cm)²/Imp + 0.306 * weight - 1.862 (R² = 0.92, SEE = 2.85 kg). Percentage accurate prediction was 76 %.

Conclusions

Compared to DXA, the Gray equation underestimated the FFM with 0.4 kg (55.7 ± 8.3), had an RMSE of 3.2 kg, 63 % accurate prediction and the smallest bias of (−0.1 %). When split by sex, the Gray equation had the narrowest range in accurate predictions, bias, and RMSE. For the assessment of FFM with BIA, the Gray-FFM equation appears to be the most accurate, but 63 % is still not at an acceptable accuracy level for obese adolescents. The new equation appears to be appropriate but await further validation. DXA measurement remains the method of choice for FFM in obese adolescents.

Trial registration

Netherlands Trial Register (ISRCTN27626398).

Growth failure associated with early neglect: pilot comparison of neglected US children and international adoptees

The long-lasting impact of different neglectful environments on growth in children is not well studied. Three groups of children, 3-10 years old, were recruited (n=60): previously institutionalized international adoptees living in stable home environments for at least 2 years (IA; n=15), children with a history of neglect born in the USA (USN; n=17), and controls (n=28). Children underwent physical examination, anthropometry, and collection of serum for growth parameters. Mean height standard deviation scores (SDS) were different (p<0.05). Age-adjusted head circumference (HC) was significantly smaller (p<0.05) in IAs. Insulin growth factor (IGF-1), a marker of growth hormone action, was higher in US neglected children. IGF-1 adjusted for age and weight SDS were different (p<0.05) between control and US neglect groups. The degree of growth failure in height and HC in IAs was more severe than neglected US children. These findings may reflect differences between the impact of chronic and intermittent deprivation on the growth hormone system.

The four-compartment model of body composition in obese Chilean schoolchildren, by pubertal stage: comparison with simpler models

OBJECTIVES

We assessed the agreement of body fat and fat-free mass measured by simpler methods against the four-compartment model (4C).

METHODS

In 60 obese schoolchildren (body mass index ≥95th percentile) between the ages of 8 and 13 y who were recruited from one school in Chile, multicompartmental body composition was estimated with the use of isotopic dilution, plethysmography (BodPod), radiographic absorptiometry (DEXA), and anthropometric equations. These results were compared to those of the 4C model, which is considered the gold standard.

RESULTS

For body fat, the 4C model showed the best agreement with DEXA for boys in Tanner stages I and II (r = 0.971) and with isotopic dilution for boys in Tanner stages III and IV (r = 0.984). The best agreement in girls occurred with isotopic dilution, regardless of pubertal stage (r = 0.948 for Tanner stages I and II; r = 0.978 for Tanner stages III and IV). Both isotopic dilution and the Huang, Ellis, and Deurenberg anthropometric equations underestimated body fat in boys; by contrast, DEXA, BodPod, and the Slaughter equation overestimated body fat in boys. All of the equations underestimated body fat in girls. For fat-free mass in both boys and girls, the 4C model showed the best agreement with isotopic dilution, regardless of pubertal stage. The Huang equation showed the best agreement for boys (r = 0.730 for Tanner stages I and II; r = 0.695 for Tanner stages III and IV) and for girls in Tanner stages I and II (r = 0.884). The Ellis equation had the best agreement for girls in Tanner stages III and IV (r = 0.917).

CONCLUSIONS

For obese Chilean children of both sexes, isotopic dilution and DEXA were the two-compartment methods that had the best agreement with the gold-standard 4C model for both body fat and fat-free mass; these were followed by the Huang and Ellis anthropometric equations.

Percent body fat prediction equations for 8- to 17-year-old American children

BACKGROUND

Percent body fat equations are usually developed in specific populations and have low generalizability.

OBJECTIVES

To use a nationally representative sample of the American youth population (8-17 years old) from the 1999-2004 National Health and Nutrition Examination Survey data to develop gender-specific percent body fat equations.

METHODS

Percent body fat equations were developed for girls and boys using information on weight, height, waist circumference, triceps skin-folds, age, race/ethnicity and menses status compared to dual-emission X-ray absorptiometry. Terms were selected using forward and backward selection in regression models in a 2/3 development sample and were cross-validated in the remaining sample. Final coefficients were estimated in the full sample.

RESULTS

Final equations included ten terms in girls and eight terms in boys including interactions with age and race/ethnicity. In the cross-validation sample, the adjusted R2 was 0.818 and the root mean squared error was 2.758 in girls. Comparable estimates in boys were 0.893 and 2.525. Systematic bias was not detected in the estimates by race/ethnicity or by body mass index categories.

CONCLUSION

Gender-specific percent body fat equations were developed in youth with a strong potential for generalizability and utilization by other investigators studying adiposity-related issues in youth.

Growing Right Onto Wellness (GROW): a family-centered, community-based obesity prevention randomized controlled trial for preschool child-parent pairs

Growing Right Onto Wellness (GROW) is a randomized controlled trial that tests the efficacy of a family-centered, community-based, behavioral intervention to prevent childhood obesity among preschool-aged children. Focusing on parent-child pairs, GROW utilizes a multi-level framework, which accounts for macro (i.e., built-environment) and micro (i.e., genetics) level systems that contribute to the childhood obesity epidemic. Six hundred parent-child pairs will be randomized to a 3-year healthy lifestyle intervention or a 3-year school readiness program. Eligible children are enrolled between ages 3 and 5, are from minority communities, and are not obese. The principal site for the GROW intervention is local community recreation centers and libraries. The primary outcome is childhood body mass index (BMI) trajectory at the end of the three-year study period. In addition to other anthropometric measurements, mediators and moderators of growth are considered, including genetics, accelerometry, and diet recall. GROW is a staged intensity intervention, consisting of intensive, maintenance, and sustainability phases. Throughout the study, parents build skills in nutrition, physical activity, and parenting, concurrently forming new social networks. Participants are taught goal-setting, self-monitoring, and problem solving techniques to facilitate sustainable behavior change. The GROW curriculum uses low health literacy communication and social media to communicate key health messages. The control arm is administered to both control and intervention participants. By conducting this trial in public community centers, and by implementing a family-centered approach to sustainable healthy childhood growth, we aim to develop an exportable community-based intervention to address the expanding public health crisis of pediatric obesity.

A PRISMA-driven systematic review of predictive equations for assessing fat and fat-free mass in healthy children and adolescents using multicomponent molecular models as the reference method

Simple methods to assess both fat (FM) and fat-free mass (FFM) are required in paediatric populations. Several bioelectrical impedance instruments (BIAs) and anthropometric equations have been developed using different criterion methods (multicomponent models) for assessing FM and FFM. Through childhood, FFM density increases while FFM hydration decreases until reaching adult values. Therefore, multicomponent models should be used as the gold standard method for developing simple techniques because two-compartment models (2C model) rely on the assumed adult values of FFM density and hydration (1.1 g/cm(3) and 73.2%, respectively). This study will review BIA and/or anthropometric-based equations for assessing body composition in paediatric populations. We reviewed English language articles from MEDLINE (1985-2012) with the selection of predictive equations developed for assessing FM and FFM using three-compartment (3C) and 4C models as criterion. Search terms included children, adolescent, childhood, adolescence, 4C model, 3C model, multicomponent model, equation, prediction, DXA, BIA, resistance, anthropometry, skinfold, FM, and FFM. A total of 14 studies (33 equations) were selected with the majority developed using DXA as the criterion method with a limited number of studies providing cross-validation results. Overall, the selected equations are useful for epidemiological studies, but some concerns still arise on an individual basis.

The multicomponent anthropometric model for assessing body composition in a male pediatric population: a simultaneous prediction of fat mass, bone mineral content, and lean soft tissue

The aim of this study was to propose and cross-validate an anthropometric model for the simultaneous estimation of fat mass (FM), bone mineral content (BMC), and lean soft tissue (LST) using DXA as the reference method. A total of 408 boys (8-18 years) were included in this sample. Whole-body FM, BMC, and LST were measured by DXA and considered as dependent variables. Independent variables included thirty-two anthropometrics measurements and maturity offset determined by the Mirwald equation. From a multivariate regression model ((n)Y(m) = (n)x(r + 1)(r + 1)β(m) + (n)ε(m)), a matrix analysis was performed resulting in a multicomponent anthropometric model. The cross-validation was executed through the sum of squares of residuals (PRESS) method. Five anthropometric variables predicted simultaneously FM, BMC, and LST. Cross-validation parameters indicated that the new model is accurate with high R(PRESS)(2) values ranging from 0.94 to 0.98 and standard error of estimate ranging from 0.01 to 0.09. The newly proposed model represents an alternative to accurately assess the body composition in male pediatric ages.

Klinische Methoden

Die Anamnese kranker Kinder ist überwiegend eine Fremdanamnese der Mutter, des Vaters oder einer Pflegeperson. Mit dem Älterwerden und besonders in der Pubertät wächst der Anspruch des kindlichen Patienten, das Gespräch selbst zu gestalten.

Anthropometric estimates of total and regional body fat in children aged 6-17 years

AIM

To develop prediction equations for total and regional (trunk, abdominal, arms and legs) body fat using surface anthropometric measures in children aged 6-17 years.

METHODS

This was a cross-sectional correlation study of 70 Caucasian children aged 6-17 years recruited from a larger randomly sampled population-based study. The independent variables included age, mass, height, body mass index, waist and hip girth, and skinfold thicknesses at eight sites. Subscapular/triceps skinfold ratio was also calculated and entered as an independent variable. The dependent variables were total body percentage fat, and fat mass for total body, trunk, abdominal region of interest, arms and legs measured using dual-energy X-ray absorptiometry (DXA). Partial least squares regression was used to determine the best predictive equation for fat percentage or fat mass in each body region in each sex.

RESULTS

Sex-specific prediction equations were developed with high coefficients of determination (r(2)), ranging from 0.869 to 0.936 in boys and from 0.900 to 0.979 in girls, absolute bias was low, and limits of agreement were narrow.

CONCLUSION

Equations were developed, which were able to predict total and regional body fat of Caucasian children aged 6-17 years using surface anthropometric measurements with high predictive accuracy.

Caucasian children's fat mass: routine anthropometry v. air-displacement plethysmography

The present paper will use fat mass percentage (FM%) obtained via BOD POD® air-displacement plethysmography (FMADP%) to examine the relative validity of (1) anthropometric measurements/indices and (2) of FM% assessed with equations (FMeq%) based on skinfold thickness and bioelectrical impedance (BIA). In 480 Belgian children (aged 5–11 years) weight, height, skinfold thickness (triceps and subscapular), body circumferences (mid-upper arm, waist and hip), foot-to-foot BIA (Tanita®) and FMADP% were measured. Anthropometric measurements and calculated indices were compared with FMADP%. Next, published equations were used to calculate FMeq% using impedance (equations of Tanita®, Tyrrell, Shaefer and Deurenberg) or skinfold thickness (equations of Slaughter, Goran, Dezenberg and Deurenberg). Both indices and equations performed better in girls than in boys. For both sexes, the sum of skinfold thicknesses resulted in the highest correlation with FMADP%, followed by triceps skinfold, arm fat area and subscapular skinfold. In general, comparing FMeq% with FMADP% indicated mostly an age and sex effect, and an increasing underestimation but less dispersion with increasing FM%. The Tanita® impedance equation and the Deurenberg skinfold equation performed the best, although none of the used equations were interchangeable with FMADP%. In conclusion, the sum of triceps and subscapular skinfold thickness is recommended as marker of FM% in the absence of specialised technologies. Nevertheless, the higher workload, cost and survey management of an immobile device like the BOD POD® remains justified.

Predicting Total Body Fat from Anthropometry in Latino Children

OBJECTIVE

To develop prediction equations for total body fat specific to Latino children, using demographic and anthropometric measures.

RESEARCH METHODS AND PROCEDURES

Ninety-six Latino children (7 to 13 years old) were studied. Two-thirds of the sample was randomized into the equation development group; the remainder served as the cross-validation group. Total body fat was measured by DXA. Measures included weight, height, waist and hip circumferences, and skinfolds (suprailiac, triceps, abdomen, subscapula, thigh, and calf).

RESULTS

The previously published equation from Dezenberg et al. did not accurately predict total body fat in Latino children. However, newly developed equations with either body weight alone (intercept +/- SE = 1.78 +/- 1.53 kg, p > 0.05; slope +/- SE = 0.90 +/- 0.07, p > 0.05 against slope = 1.0; R(2) = 0.86), weight plus age and gender (intercept +/- SE = 2.28 +/- 1.20 kg, p > 0.05; slope +/- SE = 0.91 +/- 0.05, p > 0.05; against slope = 1.0; R(2) = 0.92), or weight plus height, gender, Tanner stage, and abdominal skinfold (intercept +/- SE = 1.47 +/- 1.01 kg, p > 0.05; slope +/- SE = 0.93 +/- 0.04, p > 0.05; against slope = 1.0, R(2) = 0.97) predicted total body fat without bias.

DISCUSSION

Unique prediction equations of total body fat may be needed for Latino children. Weight, as the single most significant predictor, can be used easily to estimate total body fat in the absence of any additional measures. Including age and gender with weight produces an equally stable prediction equation with increasing precision. Using a combination of demographic and anthropometric measures, we were able to capture 97% of the variance in measured total body fat.

O uso das curvas de crescimento da Organização Mundial da Saúde em crianças e adolescentes que vivem em regiões de altitude moderada

OBJETIVO: Determinar a aplicabilidade do uso das curvas de crescimento da Organização Mundial da Saúde (OMS) em escolares que vivem em regiões de altitude moderada. MÉTODOS: Estudo transversal cuja população foi constituída por uma amostra probabilística estratificada com 955 crianças e adolescentes de seis a 12 anos, sendo 473 meninos e 482 meninas que frequentavam escolas públicas da área urbana da Região de Arequipa (Peru). As variáveis avaliadas envolveram medidas de massa corpórea (kg) e estatura (m) e índice de massa corporal. Para as comparações, utilizou-se o escore Z e o teste t para medidas pareadas. RESULTADOS: Os meninos apresentaram valores similares de massa corpórea quando comparados com a referência. No entanto, as meninas mostraram valores superiores à referência nas idades de seis, sete e dez anos (p<0,001). No caso da estatura e do índice de massa corporal, houve diferenças (p<0,001) entre a referência e os escolares de moderada altitude em todas as idades e em ambos os sexos, com estatura inferior à referência e, consequentemente, maior índice de massa corporal, sendo o escore Z para os meninos: 1,0 (seis anos), 0,69 (sete anos), 0,50 (oito anos), 1,20 (nove anos), 0,75 (dez anos) 0,41 (11 anos) e 0,82 (12 anos); para as meninas, 0,36 (seis anos), 0,53 (sete e oito anos), 0,48 (nove anos), 0,89 (dez anos), 0,55 (11 anos) e 0,43 (12 anos). CONCLUSÕES: O índice de massa corporal não deve ser aplicado a crianças e adolescentes de moderada altitude devido ao retardo no crescimento linear, o que compromete o resultado final deste índice.

Estimating total body fat using a skinfold prediction equation in Brazilian children

BACKGROUND

The double burden of obesity and underweight is increasing in developing countries and simple methods for the assessment of fat mass in children are needed.

AIM

To develop and validate a new anthropometric predication equation for assessment of fat mass in children.

SUBJECTS AND METHODS

Body composition was assessed in 145 children aged 9.8 ± 1.3 (SD) years from São Paulo, Brazil using dual energy X-ray absorptiometry (DEXA) and skinfold measurements. The study sample was divided into development and validation sub-sets to develop a new prediction equation for FM (PE).

RESULTS

Using multiple linear regression analyses, the best equation for predicting FM (R(2) = 0.77) included body weight, triceps skinfold, height, gender and age as independent variables. When cross-validated, the new PE was valid in this sample (R(2) = 0.80), while previously published equations were not.

CONCLUSION

The PE was more valid for Brazilian children that existing equations, but further studies are needed to assess the validity of this PE in other populations.