Validation of an anthropometric equation and bioelectrical impedance analysis (BIA) technique to measure body composition of children in India using D2O dilution method

Bioelectrical impedance analysis for assessment of body composition in infants and young children-A systematic literature review

Bioelectrical impedance analysis (BIA) is an easy to use, portable tool, but the accuracy of the technique in infants and young children (<24 months) remains unclear. A systematic literature review was conducted to identify studies that have developed and validated BIA equations in this age group. MEDLINE, Scopus, EMBASE, and CENTRAL were searched for relevant literature published up until June 30, 2020, using terms related to bioelectrical impedance, body composition, and paediatrics. Two reviewers independently screened studies for eligibility, resulting in 15 studies that had developed and/or validated equations. Forty-six equations were developed and 34 validations were conducted. Most equations were developed in young infants (≤6 months), whereas only seven were developed among older infants and children (6-24 months). Most studies were identified as having a high risk of bias, and only a few included predominantly healthy children born at term. Using the best available evidence, BIA appears to predict body composition at least as well as other body composition tools; however, among younger infants BIA may provide little benefit over anthropometry-based prediction equations. Currently, none of the available equations can be recommended for use in research or in clinical practice.

Physical Activity and the Home Environment of Pre-School-Aged Children in Urban Bangladesh

Physical activity (PA) is a key determinant of health and development, yet few studies have examined PA levels and risk factors for low PA among young children in low- and middle-income countries. This study aimed to describe the PA and sedentary (SED) behavior levels of preschool-aged children in Dhaka, Bangladesh, and to estimate the associations between potential risk factors in the home built environment and moderate to vigorous PA (MVPA). In a sample of preschool-aged children (n = 65) in Dhaka, PA and SED behavior were measured for 7 days using ActiGraph GT3X-BT accelerometers. Characteristics of the home built environment, socioeconomic factors, and anthropometry were also measured. Linear mixed-effects models were used to estimate multivariable-adjusted associations between characteristics of the home environment and MVPA. Preschool-aged children spent a mean (±standard deviation) 421 ± 48 and 82 ± 23 min per day sedentary and in MVPA, respectively. There were no statistically significant associations between factors in the home built environment (indoor area, presence of an open stairwell, and presence of gross motor activity facilitating items) and MVPA. These findings suggest that the studied characteristics of the home built environment may not significantly influence the MVPA observed among preschool-aged children in Dhaka. Future research should focus on other structural and behavioral factors that facilitate PA among young children in dense urban settings.

Supplementation with Fortified Lipid-Based and Blended Complementary Foods has Variable Impact on Body Composition Among Rural Bangladeshi Children: A Cluster-Randomized Controlled Trial

BACKGROUND

Complementary food supplementation enhances linear growth and may affect body composition in children.

OBJECTIVE

We aimed to determine the effect of complementary food supplements provided from the age of 6 to 18 mo on fat-free mass (FFM) and fat mass (FM) gain among children in rural Bangladesh.

METHODS

In an unblinded, cluster-randomized, controlled trial we tested the effects of 4 complementary food supplements for 1 y [chickpea, rice lentil, Plumpy'doz, and wheat-soy-blend++ (WSB++)] compared with no supplements on linear growth. Body composition was estimated using weight-length-based, age- and sex-specific equations at 6, 9, 12, 15, and 18 mo and postintervention aged 24 mo. Generalized estimating equations (GEEs) were applied to estimate the effect of each complementary food on mean FFM and FM from 9 to 18 and 24 mo compared with the control, adjusting for baseline measures. Sex interactions were also explored.

RESULTS

In total, 3592 (65.9% of enrolled) children completed all anthropometric assessments. Estimated FFM and FM (mean ± SD) were 5.3 ± 0.6 kg and 1.4 ± 0.4 kg, respectively, at the age of 6 mo. Mean ± SE FFM and FM from 9 to 18 mo were 75.4 ± 14.0 g and 32.9 ± 7.1 g, and 61.0 ± 16.6 g and 30.0 ± 8.4 g, higher with Plumpy'doz and chickpea foods, respectively, than the control (P < 0.001). Estimated FFM was 41.5 ± 16.6 g higher in rice-lentil-fed versus control (P < 0.05) children. WSB++ had no impact on FFM or FM. A group-sex interaction (P < 0.1) was apparent with Plumpy'doz and rice-lentil foods, with girls involved in the intervention having higher estimated FFM and FM than control girls compared with no significant effect in boys. At 24 mo, FFM and FM remained higher only in girls eating Plumpy'doz compared with the controls (P < 0.01).

CONCLUSIONS

In this randomized trial, supplementation effected small shifts in apparent body composition in rural Bangladeshi children. Where seen, FFM increments were twice that of FM, in proportion to these compartments, and more pronounced in girls. FFM increased in line with reported improvements in length. This trial was registered at clinicaltrials.gov as NCT01562379.

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

Study Objectives:

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

Methods:

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

Results:

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

Conclusions:

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

Total body water and fat-free mass: evaluation of equations based on bioelectrical impedance analysis in infants and young children in India

The association of early postnatal growth with diseases in adults such as hypertension, type 2 diabetes and CHD has generated interest in studying postnatal growth. Bioelectrical impedance analysis (BIA) is a useful measure to estimate total body water (TBW) and fat-free mass (FFM). We evaluated three published equations (Fjeld et al. (Pediatr Res (1990) 27, 98-102), Bocage (MSc Thesis (1988) University of West Indies) and Kushner et al. (Am J Clin Nutr (1992) 56, 835-839) to measure TBW and derived FFM based on BIA, using 2H2O dilution as a reference method for suitability in infants in India. In a cross-sectional study in seventy-eight apparently healthy infants aged 6-24 months from the urban poor attending an immunisation clinic at a hospital in Kolkata, we measured their length to the nearest 0.1 cm, weight to the nearest 10 g, resistance at 50 kHz using BIA and TBW using 2H2O dilution. TBW was derived using three published BIA-based equations and compared with TBW using 2H2O dilution. Based on the BIA equations of Fjeld et al., Bocage and Kushner et al., the mean TBW values were 2.46 % (P < 0.001), 4.62 % (P < 0.001) and 9.50 % (P < 0.001) lower than the reference 2H2O method, respectively. All three published BIA-based equations consistently underestimated the TBW and FFM and appeared inadequate for studying infants in India. The equation described by Fjeld et al. gave the smallest deviation from the reference method and may be used for field studies. New equations based on population-specific data are desirable for a more precise measure of TBW.

Evaluation of equations for fat-free mass based on anthropometry in infants and young children in South Asia

Rapid postnatal growth in low-birth weight infants increases the risk of hypertension, CHD and type 2 diabetes in adult life. To provide validated tools to study the growth in South Asian infants, we evaluated two published equations to measure total body water (TBW) and fat-free mass (FFM) based on anthropometry in 6- to 24-month-old infants, using 2H2O dilution. In a method-comparison study in seventy-eight infants aged 6-24 months (forty-two girls and thirty-six boys) from the urban poor attending an immunisation clinic of a hospital in Kolkata, we measured their length to the nearest 0.1 cm, weight to the nearest 10 g and TBW using 2H2O dilution. The calculated TBW in kg (TBWkg) and FFM in kg (FFMkg) using two equations based on the length and weight were each compared with TBWkg and FFMkg calculated from 2H2O dilution. The mean FFMkg were 7.31 (sd 1.11), 7.13 (SD 1.08) and 7.26 (SD 1.13) by the 2H2O dilution method, and the anthropometry equations of Mellits and Cheek (AN-1) and Morgenstern et al. (AN-2), respectively. The mean of the paired difference in FFMkg was 0.18 (SEM 0.06) and 0.04 (SEM 0.07) between 2H2O, and AN-1 and AN-2, respectively. There is a good agreement for FFM derived by AN-2 with 2H2O dilution. The former is 1% lower than that obtained from the reference method (P=0.28). The AN-2 equation is useful for evaluating FFM in infants in India.

Impact of ethnicity upon body composition assessment in Sri Lankan Australian children

OBJECTIVES

Obesity is a disease with excess body fat where health is adversely affected. Therefore it is prudent to make the diagnosis of obesity based on the measure of percentage body fat. Body composition of a group of Australian children of Sri Lankan origin were studied to evaluate the applicability of some bedside techniques in the measurement of percentage body fat.

METHODS

Height (H) and weight (W) was measured and BMI (W/H(2)) calculated. Bioelectrical impedance analysis (BIA) was measured using tetra polar technique with an 800 microA current of 50 Hz frequency. Total body water was used as a reference method and was determined by deuterium dilution and fat free mass and hence fat mass (FM) derived using age and gender specific constants. Percentage FM was estimated using four predictive equations, which used BIA and anthropometric measurements.

RESULTS

Twenty-seven boys and 15 girls were studied with mean ages being 9.1 years and 9.6 years, respectively. Girls had a significantly higher FM compared to boys. The mean percentage FM of boys (22.9 +/- 8.7%) was higher than the limit for obesity and for girls (29.0 +/- 6.0%) it was just below the cut-off. BMI was comparatively low. All but BIA equation in boys under estimated the percentage FM. The impedance index and weight showed a strong association with total body water (r(2)= 0.96, P < 0.001). Except for BIA in boys all other techniques under diagnosed obesity.

CONCLUSIONS

Sri Lankan Australian children appear to have a high percentage of fat with a low BMI and some of the available indirect techniques are not helpful in the assessment of body composition. Therefore ethnic and/or population specific predictive equations have to be developed for the assessment of body composition, especially in a multicultural society using indirect methods such as BIA or anthropometry.

Empirically derived new equations for calculating body fat percentage based on skinfold thickness and midarm circumference in preschool Indian children

We wanted to develop and apply new equations based on skinfold and midarm measurements for estimating %fat in preschool children suitable for field use. Prediction equations were developed on preschool-aged urban boys (n = 100) and girls (n = 84). Skinfolds at four sites and midarm measurements were regressed on %fat derived from equations based on height and weight and from bioelectrical impedance analysis (BIA; resistance at 50 kHz). These equations were applied: 1) to 12 children in whom the %fat was determined using D2O dilution, and 2) to 50 children in whom their %fat was derived using height-weight and BIA equations. The 95% limits of agreement (mean +/- 2 SD) for %fat derived by anthropometry and by new equations were within 1.7% in boys (r = 0.85; P < 0.001) and girls (r = 0.90; P < 0.001) and by BIA and new equations were within 1.5% in boys (r = 0.82; P < 0.001) and 2% in girls (r = 0.88; P < 0.001). For %fat measured by D2O dilution and new equations, 95% limits of agreement was within 1.3% (r = 0.98; P < 0.001). In 50 children 95% limits of agreement between anthropometry and new equations were within 1.8% in boys (r = 0.88; P < 0.001) and 1.4% in girls (r = 0.92; P < 0.001) and between BIA and new equations were within 1% in boys (r = 0.91; P < 0.001) and 1.5% in girls (r = 0.89; P < 0.001). The new equations for measuring %fat based on midarm circumference and skinfold measurements are rapid and accurate for South Asian children and should be useful for prediction of body composition and nutritional survey in field studies.

Lean body mass in preschool aged urban children in India: gender difference

OBJECTIVE

To estimate lean body mass (LBM) in preschool aged boys and girls in India and explore gender difference.

DESIGN

Crossectional.

SETTING

Immunization clinic of a charitable Government General Hospital in Kolkata, India.

SUBJECTS

Two-hundred and forty-five children (147 boys and 98 girls) aged 1-5 y from among the urban poor were admitted in the study between July 1999 and December 2000. Children with acute or chronic illness or congenital malformation were excluded.

METHOD

Length/height to the nearest 0.1 cm, weight to the nearest 10 g and total body resistance using multifrequency bioelectrical (Xitron 4000B) impedance analyzer (BIA) at 50 kHz were measured. Their nutritional status was compared with National Center for Health Statistics (NCHS) median data and lean body mass (LBM) was calculated using anthropometry and BIA equations. The groups were compared using analysis of variance and multiple linear regression.

RESULTS

Girls were more stunted (P<0.001) and underweight (P<0.047), while the degree of wasting was similar. Mean LBM percentage was higher in boys compared with girls by anthropometry (P<0.001) and BIA (P<0.005), which persisted after adjusting for age. With increasing age, LBM percentage declined in girls (P<0.02) in contrast to reference girls, in whom it increased. In boys LBM percentage increased with age as is in reference boys.

CONCLUSIONS

In addition to the girls being more stunted and underweight, LBM% decreased in girls with increasing age but steadily increased in boys, suggesting hidden deprivation of female children.