Validation of Simple Epidemiological or Clinical Methods for the Measurement of Body Composition in Young Children

Objective:

The present study aimed to determine the validity of simple epidemiological and clinical methods for the assessment of body fatness in preschool children.

Methods:

In 89 children (42 boys, 47 girls; mean age 4.1 SD 1.3y) measures of body fatness were made using total body water (TBW), dual energy x-ray absorptiometry (DXA), air displacement plethysmography (BODPOD) and skinfold thickness. Methods were compared by Bland–Altman analysis using TBW as the reference method, and by paired comparisons and rank order correlations.

Findings:

Bias for DXA was +1.8% body fat percentage units (limits of agreement +15.5% to −11.9%), bias for BODPOD was −3.5% (limits of agreement +18.9% to −5.9%) and bias for skinfolds using the Slaughter equations was −6.5% (limits of agreement +10.0% to −23.1%). Significant rank order correlations with TBW measures of fatness were obtained for DXA estimates of fatness (r=0.54, P=0.01), but not for estimates of fat by skinfold thickness (r=0.20, P=0.2) or BODPOD (r=0.25, P=0.1). Differences between both DXA and BODPOD and the reference TBW estimates of body fatness were not significant (P=0.06 and P=0.1 respectively); however, the difference in estimated body fatness between skinfold thickness and TBW was significant (P<0.001).

Conclusion:

Estimates of body fatness in preschool children were inaccurate at the level of the individual child using all the methods, but DXA might provide unbiased estimates and a means of making relative assessments of body fatness.     

Influence of sports on development of 10 and 11-year-old boys. I. Body composition, anthropometry and creatinine excretion

We compared body composition (measured by total-body water determination), skinfolds, body circumferences and diameters and the muscle arm area of 10 to 11-year-old boys (n = 21) at the beginning and the end of a 9-months training period (track-and field athletics) with data obtained in 12 control subjects of corresponding ages. Urinary creatinine excretion was measured as a parameter of muscle mass at the end of the training period. Boys engaged in training gained (mean: + 2,6 kg) significantly less (p less than 0,05) weight than controls (mean: + 3,9 kg). Fat-free mass (FFM) as percentage of weight significantly increased in boys engaged in training (mean: + 1,8%; p less than 0,005) at the expense of fat whereas in controls (mean: + 0,6%; p: n.s.) there was no significant change. Decreasing skinfold thickness in boys engaged in training indicated reduction of subcutaneous fat. In controls, subcutaneous fat increased at the trunk and decreased at the periphery. Regression analysis indicated that changes of triceps skinfold thickness did not reflect changes in body fat content (r = 0.30; p: n.s.). A significant relation was established between changes of the subcapular skinfold thickness (r = 0,46; p less than 0,005) and of the sum of 5 skinfolds on the one hand (r = 0,51; p less than 0,005) and the changes of body fat content on the other hand. High standard deviations from the regression lines, however, indicated that accurate prediction of changes in body fat content was not possible in an individual subject.(ABSTRACT TRUNCATED AT 250 WORDS)     

Correlations between high level sport-climbing and the development of adolescents

Over the last years concerns have been raised about the health effects particularly on young climbers due to the observation of short stature with low body weight and body fat in sports climbers. The aim of this study was to investigate anthropometric and hormonal data for climbers of the German Junior national team. 16 climbers were compared with 14-age matched nonclimbers with respect to several anthropometric variables, leptin level, and climbing characteristics. Height, weight and body mass index (BMI) standard deviation scores (SDS) for boys were not significantly different from the controls, whereas girls had significantly lower SDS-values for weight and BMI. In comparison with the control group boys and girls had a lower skinfold thickness. The leptin values were lower than the calculated leptin levels but only reached significance for the girls. The young athletes of the GJNT were neither of short stature nor thin when compared with a physically active control group. The low body fat in boys and girls was within expected limits. The lower leptin levels might be attributed to a decrease in total body fat.     

Body fat ratios in urban Chinese children

OBJECTIVE: As obesity has been increasing in China, the present study examined the body composition of children to assess their fatness. STUDY DESIGN: A total of 532 healthy schoolchildren who lived in central Beijing were examined. Skinfold thicknesses, hip and waist circumferences, and body fat percentage were measured, as well as height and weight. RESULTS: The prevalence of overweight (Body Mass Index (BMI) >or= 95% for age and sex of Chinese children) was 27.7% in boys and 14.2% in girls (chi-squared; P = 0.0001). The percentages of body fat (BF%), waist/hip ratios and skinfold thicknesses ratios (subscapular/triceps) in overweight children were significantly higher than those in non-overweight children (Mann-Whitney U-test). The BF% of non-overweight boys was significantly higher than that of non-overweight girls. CONCLUSION: Urban Chinese overweight children have high BF% with adverse fat distribution. They may have high risk of atherogeniety. Boys in the non-overweight category may have higher fat accumulation than predicted by BMI. The establishment of an intervention program for childhood obesity is strongly recommended.     

Body composition in neonates: relationship between measured and derived anthropometry with dual-energy X-ray absorptiometry measurements

This study examined the relationship between measured and derived anthropometric measurements with dual-energy X-ray absorptiometry measured lean and fat mass at 3.0 +/- 2.8 (SD) days in 120 neonates with birth weights appropriate (AGA; n=74), large (LGA; n=30); or small (SGA, n=16) for gestational age. Anthropometric measurements, including total body weight and length, and regional measurements, including circumferences of head, chest, abdomen, midarm, and midthigh and dynamic skinfold thickness (15 and 60 s) at tricep, subscapular, suprailiac, and midthigh, were performed. Derived anthropometry included muscle and fat areas, and ratios were calculated from direct measurements. The skinfold thickness measurements between 15 and 60 s were highly correlated (r=0.973-0.996, p <0.001 for all comparisons). Strong correlations existed within the four circumferences of trunk and extremities, the four skinfolds, and the ratios of weight to length and its higher powers. Weight and length accounted for >97% of the variance of lean mass in AGA and SGA infants and 46% of the variance in LGA infants and for 80, 82, and 84% of the variance of fat mass in SGA, AGA, and LGA infants, respectively, whereas midarm:head circumference ratio and arm muscle and fat areas are the most important derived anthropometry in the prediction for body composition. They independently accounted for up to 16.5 and 10.2%, respectively, of the variance in body composition depending on the state of in utero growth. Thus, total body weight and length and some selected regional and derived anthropometry accounted for the vast majority of the variance of body composition.     

The relationship between different subcutaneous adipose tissue layers, fat mass and leptin in obese children and adolescents

We studied the relationships of subcutaneous adipose tissue layers (SAT-layers), body fat mass (FM) and waist-to-hip ratio (WHR) with leptin in obese children and adolescents. Twenty-nine obese children and adolescents (12 boys: age: 11.3 +/- 3.7 yr; body mass index [BMI]: 28.5 +/- 4) and 17 girls (age: 12.2 +/- 2.2 yr; BMI: 29.8 +/- 4.7) (mean +/- SD) were studied. FM was estimated by bioelectrical impedance. SAT-layers were determined at 15 different body sites from 1-neck to 15-calf by the Lipometer optical device. Leptin and insulin were determined by RIA. Maturity was associated with a greater thickness of certain SAT-layers from the upper body and with a lower thickness of SAT-layers from the abdominal region and lower extremities. Significant correlations were found for all estimates of adiposity and leptin (all p<0.001). Waist and hip circumferences were not correlated to leptin after adjustment for FM. SAT-layers from the upper body were significantly and positively correlated to leptin. Multiple regression analysis revealed FM as a main contributor to the variation in leptin (R2=0.53, p<0.0001). FM together with SAT-layers 5-front chest and 13-rear thigh explained 72% of the variation in leptin (p<0.0001). In a body fat distribution model, hip circumference together with SAT-layers 4-upper back and 2-triceps explained 75% of the variation in leptin (p< 0.0001). The results suggest that SAT-layers and their topography are main determinants for leptin in obese children and adolescents. Maturity in obese children is associated with higher values of upper body SAT-layers and lower values of abdominal and lower extremities SAT-layers. Whether leptin is under the control of certain subcutaneous adipose tissue depots from the upper body remains to be elucidated by longitudinal studies.     

Birth weight and body fat distribution in adolescent girls

OBJECTIVE: To examine the association between birth weight and body fat distribution in a group of adolescent girls. DESIGN: A total of 216 white girls who were born in Southampton had their heights, weights, waist and hip circumferences, and skinfold thicknesses measured when they were aged between 14 and 16 years. RESULTS: The girls who were smallest at birth, but who were fattest at time of measurement were the most centrally obese. In girls whose body mass index was above the median (21 kg/m2), the subscapular to triceps skinfold ratio rose by 9% for every kilogram decrease in birth weight. Among overweight girls, with a body mass index over 25, the ratio rose by 27% for every kilogram decrease in birth weight. CONCLUSION: In adolescent girls, the tendency to store fat on the trunk rather than the limbs, seems to be programmed by growth in fetal life, and is most evident in those who are overweight.     

Effect of growth hormone on height, weight, and body composition in Prader-Willi syndrome

AIMS: To evaluate the effect of the administration of growth hormone on stature, body weight, and body composition in children aged between 4 and 10 years with Prader-Willi syndrome. METHODS: Height, weight, and skinfold thickness were recorded in 25 children using standard anthropometric techniques at recruitment, and six months later, shortly before the start of daily subcutaneous injections of growth hormone. Body composition was assessed via a measurement of total body water using stable isotopes. Measurements were repeated at the end of the six months of growth hormone administration. Measurements of height, weight, and skinfold thickness were expressed as standard deviation scores (SDSs). RESULTS: There was a significant reduction in the percentage of body fat after growth hormone treatment; height velocity doubled during treatment; body weight did not change significantly when expressed as an SDS. Skinfold thickness at both the triceps and subscapular site decreased in absolute terms and when expressed as an SDS. CONCLUSIONS: These results indicate sufficient potential benefit to justify a more prolonged trial of growth hormone treatment and an exploration of different dosage regimens in children with Prader-Willi syndrome.     

A critique of the expression of paediatric body composition data.

There is increasing interest in body composition in paediatric research, as distinct from growth and nutritional status, as almost all diseases have adverse effects on either fatness or the fat-free mass. However, the approaches used to assess growth and nutritional status are not appropriate for separate evaluations of body fatness and lean mass. Traditional measurements such as body mass index and skinfold thickness do not measure fat in accurate quantitative terms. Various techniques have been used in recent years which divide body weight into fat mass and fat-free mass; however, the data tend not to be appropriately expressed. Body fatness is generally expressed as a percentage of weight, while fat-free mass typically remains unadjusted for size. A more appropriate approach is to normalise both body fatness and fat-free mass for height. This recommendation is relevant both to studies comparing patients with controls and to the expression of new reference data on body composition which are needed to allow informative comparisons. The same approach is appropriate for the classification of childhood obesity.     

A critique of the expression of paediatric body composition data

There is increasing interest in body composition in paediatric research, as distinct from growth and nutritional status, as almost all diseases have adverse effects on either fatness or the fat-free mass. However, the approaches used to assess growth and nutritional status are not appropriate for separate evaluations of body fatness and lean mass. Traditional measurements such as body mass index and skinfold thickness do not measure fat in accurate quantitative terms. Various techniques have been used in recent years which divide body weight into fat mass and fat-free mass; however, the data tend not to be appropriately expressed. Body fatness is generally expressed as a percentage of weight, while fat-free mass typically remains unadjusted for size. A more appropriate approach is to normalise both body fatness and fat-free mass for height. This recommendation is relevant both to studies comparing patients with controls and to the expression of new reference data on body composition which are needed to allow informative comparisons. The same approach is appropriate for the classification of childhood obesity.     

Gender differences in newborn subcutaneous fat distribution

The pattern and distribution of subcutaneous fat in term and preterm newborns has been assessed by skinfold thicknesses (ST), describing gender and gestational age variations. Weight, length and ST (triceps, biceps, subscapular and suprailiac) were measured in 4634 neonates (2445 males and 2189 females) aged from 32 to 41 gestational weeks. Central to total skinfold ratio (CTS), (suprailiac + subscapular)/sum of 4 ST, was calculated. Males were heavier and longer than females. The sum of 4 ST and CTS was higher in females at every gestational age (with significant differences from 35 weeks) and also the sum of 4 ST per kg body weight (P<0.05 from 32–33 weeks). Throughout the gestational period, ST increased significantly (P<0.0001) but CTS did not show variations, neither in males nor in females. Conclusion: term and preterm females have a more centralised pattern and more amount of subcutaneous fat than males. Central to total skinfold ratio must be considered as an index of centripetal fat store which is independant of gestational age.Abbreviations BS biceps skinfold thickness - CTS central to total skinfold ratio - DXA dual energy X-ray absorptiometry - FFM fat-free mass - FM fat mass - SBS subscapular skinfold thickness - SPS suprailiac skinfold thickness - ST skinfold thickness - ST the sum of the four skinfolds (biceps, triceps, subscapular and suprailiac) - TS triceps skinfold thickness     

Longitudinal growth data of development of weight, height, skinfold thickness, head-, chest- and abdominal circumferences in healthy children (author's transl)

From 1974--1977 anthropometric investigations were performed in 173 healthy infants during the first year of life. Weight, height, skinfold thickness, head-, chest-, and abdominal circumferences had been measured as parameters for growth. Birth weight increased ceased threefold on 12th month in males only. There is no difference in the increase of height in males and females. Width of skinfold thickness increases rapidly until month 5, except abdominal skinfold. A radual decrease follows thereafter. The difference in decreasing velocity of skinfold thickness indicates changes in distribution of subcutaneous fat tissue during infancy. Growth of head-, chest-, and abdominal circumferences of males are similar to that of females.     

Preliminary data on the association between waist circumference and insulin resistance in children without a previous diagnosis

The aim of the present work was to study the association between different anthropometric parameters and insulin resistance (IR) in Spanish schoolchildren without a previous diagnosis. A total of 443 Spanish schoolchildren (9–11 years of age) were studied in this cross-sectional study. The anthropometric measurements collected were weight, height, body circumferences and skinfolds. Body mass index (BMI), waist/hip ratio, percentage body fat and fat-free body mass were determined. Overnight-fasted blood lipids, insulin and glucose levels were analysed, and estimation of IR, taking into account the homeostasis model assessment (HOMA), was calculated. The children with IR had higher serum triglycerides and insulin levels, were heavier and taller, and had a higher BMI, a larger waist circumference, a larger hip circumference, a larger waist/hip ratio and thicker bicipital and tricipital skinfolds than those who did not have IR. Age, sex, BMI and waist circumference explained 32.0% of the variance in the HOMA values; only sex, triglycerides and waist circumference independently influenced this variable. A 1-cm increase in waist circumference was associated with approximately a 3.8% increase in the mean HOMA value. The children with a waist circumference of over the p90 for their age and sex were at greater risk of showing IR as measured by the HOMA: odds ratio = 6.94 (2.01–23.91; P < 0.001). In conclusion, according to these results, waist circumference is the best anthropometric parameter associated with IR in children, and those with a waist circumference of over the p90 for their age and sex would appear to be at particular risk.     

Moderate–vigorous physical activity and body fatness in Chinese urban school children

Background: The exact relation between moderate-vigorous physical activity (MVPA) and body fatness in children has yet to be fully defined. This study examined the relationship between MVPA and body fatness in Chinese urban school children aged 9-11 years, in an 8 month longitudinal study. Methods: Two hundred and ten children (aged 9-11 years; 97 boys and 113 girls) were recruited from two public primary schools in the Beijing urban area. The baseline and the 8 month follow-up percent body fat (fat%), fat mass (FM), body mass index (BMI), waist size, hip size and the waist : hip ratio were investigated as measures of body fatness. Habitual MVPA level (activity-related energy expenditure, AEE) was measured using a validated self-report questionnaire recall. Results: Nine-year-old girls who were in the top quartile for MVPA had significantly lower fat% than other girls at the same age (P < 0.05); 10-11-years girls who were in the top quartile for MVPA had significantly less increase in all of the indices of body fatness (P < 0.05). There was no difference in fat% between the highly physically active (top quartile for MVPA) and less active 9-11 year boys in both cross-sectional and longitudinal statistical analyses. Conclusions: Highly physically active girls had lower fat% and less increase in body fatness. In light of world trends showing increasing childhood obesity, this study supports the hypothesis that MVPA might be effective in fighting excess body fat gain in Chinese school-age girls.     

Epidemiology of whole body,peripheral, and central adiposity in adolescents from a Brazilian state capital

The aim of this study was to associate the epidemiology of whole body, peripheral, and central adiposity with sociodemographic characteristics, health-related behaviors, and biological maturation of adolescents from a Brazilian state capital. A cross-sectional school-based study was conducted in Florianopolis, Santa Catarina, Brazil with 818 adolescents aged 14 to 18 years, and 61.8% female. The peripheral adiposity was assessed by the triceps skinfold thickness and the central adiposity by the subscapular skinfold thickness, using cutoff greater than or equal to percentile 90 of the Centers for Disease Control and Prevention reference curve. Adolescents with high whole body adiposity were those showing skinfold thickness values above the reference percentile. Logistic regression analysis was applied using multivariable model. The prevalence of high whole body, peripheral, and central adiposity was 8.0%, 8.7%, and 10.3% for boys and 3.8%, 6.3%, and 11.1% for girls, respectively. Factors associated with this outcome in boys were overweight/obesity and low aerobic fitness (p < 0.05). Besides these factors, girls were also associated with excessive body fat, low paternal schooling, and puberty status (p < 0.05). Physical activity, sedentary behavior, and eating habits were not associated with this outcome. It was concluded that the main predictors of high body adiposity were overweight and low aerobic fitness in both sexes and low parental schooling and puberty status in females.     

Truncal adiposity is present at birth and in early childhood in South Indian children

OBJECTIVES: Muscle-thin but adipose ('thin-fat') body composition of south Asian adults contributes to their high risk of type 2 diabetes. Studies in Pune, India showed that this phenotype is present at birth. We aimed to determine if south Indian babies have a 'thin-fat' phenotype and if this persists in childhood. DESIGN: Prospective cohort study. SETTING: Holdsworth Memorial Hospital, Mysore, India. SUBJECTS: Children (n = 663) whose mothers were recruited from the antenatal clinics. METHODS: Weight, length, head, mid-upper-arm, abdominal circumferences; triceps and subscapular skinfolds were measured at birth, one and four years, and compared with white Caucasian babies born in Southampton, UK (birth), and UK and Dutch growth standards (one and four years). RESULTS: Mysore babies were lighter (2983 g vs 3472 g; -1.10 SD, CI -1.16, -1.02) and smaller in all body measurements than UK neonates (P < 0.001). The deficit was greatest for mid-upper-arm (-1.07 SD), head (-0.89 SD) and abdominal circumferences (-0.73 SD), and least for length (-0.25 SD) and subscapular skinfold thickness (-0.19 SD). Predictors of skinfold thickness were maternal body mass index (P < 0.001) and socio-economic status (P = 0.05). At four years, subscapular skinfold thickness was larger than UK (+0.18 SD, CI +0.11, +0.25; P < 0.001) and Dutch standards (+0.61 SD, CI +0.51, +0.71; P < 0.001), despite all other body measurements remaining smaller. Predictors of 4-year skinfold thickness were neonatal skinfold thickness (P = 0.001) and maternal insulin concentrations (P = 0.05). CONCLUSIONS: Mysore newborns have a 'thin-fat' phenotype. This may reflect the action of genes and/or the 'maternal environment'. The phenotype persists in childhood, and may be the forerunner of a diabetogenic adult phenotype.     

Correlates of adiponectin and the leptin/adiponectin ratio in obese and non-obese children

Adiponectin is an adipocyte secreted protein that has been reported to increase fatty acid oxidation and improve insulin sensitivity. Our aim was to study the relationship between adiponectin and leptin, body fat, insulin and lipoproteins in obese compared to non-obese children matched for age and gender. Adiponectin serum concentrations were significantly lower in the obese compared to the non-obese children (9.1+/-3.7 vs 17.1+/-12.3 microg/ml, p <0.05), in contrast to serum leptin concentrations which were greater in the obese compared to the non-obese subjects (31.8+/-11.1 vs 8.2+/-5.7 ng/ml, p <0.001). When considered as a single group to assess adiponectin concentrations over a spectrum of body size, adiponectin values correlated inversely with body weight (r = -0.33, p <0.05) and BMI (r = -0.35, p <0.05). Adiponectin values correlated directly with HDL-C (r = 0.47, p <0.005), but not with total cholesterol, IGF-I, or leptin binding activity. Since leptin and adiponectin change inversely in relation to BMI, the leptin/adiponectin (L/A) ratio was determined as a potential index relating adiposity to the development of complications of obesity. The L/A ratio was eight-fold greater in the obese compared to the non-obese children, and correlated more strongly with BMI (r = 0.779, p <0.0001) and with HDL-C (r = -0.53, p <0.001), than did adiponectin alone. The L/A ratio also correlated significantly with triceps skinfold thickness (TSF) (r = 0.77, p <0.001) and percent body fat (r = 0.79, p <0.0001) in non-obese children. These data suggest that adiponectin concentrations are already differentially regulated in childhood obesity. The index of increased leptin concentration corrected by reduced adiponectin values (L/A ratio) merits investigation as a marker for morbidities associated with childhood obesity.     

Effect of growth hormone on height,weight, and body composition in Prader-Willi syndrome

AIMS—To evaluate the effect of the administration of growth hormone on stature, body weight, and body composition in children aged between 4 and 10 years with Prader-Willi syndrome.
METHODS—Height, weight, and skinfold thickness were recorded in 25 children using standard anthropometric techniques at recruitment, and six months later, shortly before the start of daily subcutaneous injections of growth hormone. Body composition was assessed via a measurement of total body water using stable isotopes. Measurements were repeated at the end of the six months of growth hormone administration. Measurements of height, weight, and skinfold thickness were expressed as standard deviation scores (SDSs).
RESULTS—There was a significant reduction in the percentage of body fat after growth hormone treatment; height velocity doubled during treatment; body weight did not change significantly when expressed as an SDS. Skinfold thickness at both the triceps and subscapular site decreased in absolute terms and when expressed as an SDS.
CONCLUSIONS—These results indicate sufficient potential benefit to justify a more prolonged trial of growth hormone treatment and an exploration of different dosage regimens in children with Prader-Willi syndrome.

     

Total energy expenditure and body composition in early infancy.

In adults greater energy expenditure, primarily on physical activity, is associated with greater leanness. Such an association has proved more difficult to demonstrate in infants, partly due to the difficulty of measuring fatness and free living energy expenditure in this age group. Stable isotope techniques now make such investigations more viable. OBJECTIVE: The relationship between body composition and energy expenditure was investigated in 12 week infants. METHODS: Total energy expenditure and fat mass were estimated using the doubly labelled water technique. SUBJECTS: 92 normal healthy infants. RESULTS: Fat mass was correlated with both triceps and subscapular skinfold thicknesses (p < 0.001). After controlling for body size, age was a significant predictor of fat mass (p = 0.003), whereas total energy expenditure was not (p = 0.463). CONCLUSIONS: The cross sectional link between activity level and fatness in young infants, reported previously, does not persist when energy expenditure is considered.     

Serum leptin levels during childhood and adolescence: relationship with age, sex, adiposity and puberty

We studied serum leptin levels in 189 healthy children to evaluate related factors during childhood and adolescence. Leptin correlated with body mass index (BMI), triceps skinfold thickness (p<0.001) and body weight (p<0.01). Obese children and girls had higher leptin levels than non-obese children and boys, respectively (p<0.001). In girls, leptin correlated positively with age, skinfold thickness and BMI (p<0.001). In boys, leptin correlated negatively with age (p<0.001) and positively with skinfold thickness (p<0.05). Prepubertal boys had higher leptin levels than prepubertal girls and pubertal boys (p<0.05). Pubertal girls had higher leptin levels than prepubertal girls and pubertal boys (p<0.001). Leptin levels in girls were higher at Tanner stages 4 and 5 than at stage 1 (p<0.001). In conclusion, serum leptin levels are related with adiposity, have obviously age-related gender differences during childhood and adolescence, and may be involved in the maturation of reproductive capacity.