Validation of total body water analysis by bioelectrical impedance analysis with deuterium dilution in (pre)school children

Overview of BMI and Other Ways of Measuring and Screening for Obesity in Pediatric Patients

Despite a long history of advances in measuring body size and composition, body mass index (BMI) has remained the most commonly used clinical measure. We explore the advantages and disadvantages of using BMI and other measures to estimate adipose tissue, recognizing that no measure of body size or adiposity has fulfilled the goal of differentiating health from disease. BMI and waist circumference remain widely-used clinical screening measures for appropriate risk stratification as it relates to obesity.

The Effects of a Preconception Lifestyle Intervention on Childhood Cardiometabolic Health—Follow-Up of a Randomized Controlled Trial

Maternal obesity is associated with adverse metabolic outcomes in her offspring, from the earliest stages of development leading to obesity and poorer cardiometabolic health in her offspring. We investigated whether an effective preconception lifestyle intervention in obese women affected cardiometabolic health of their offspring. We randomly allocated 577 infertile women with obesity to a 6-month lifestyle intervention, or to prompt infertility management. Of the 305 eligible children, despite intensive efforts, 17 in the intervention and 29 in the control group were available for follow-up at age 3–6 years. We compared the child’s Body Mass Index (BMI) Z score, waist and hip circumference, body-fat percentage, blood pressure Z scores, pulse wave velocity and serum lipids, glucose and insulin concentrations. Between the intervention and control groups, the mean (±SD) offspring BMI Z score (0.69 (±1.17) vs. 0.62 (±1.04)) and systolic and diastolic blood pressure Z scores (0.45 (±0.65) vs. 0.54 (±0.57); 0.91 (±0.66) vs. 0.96 (±0.57)) were similar, although elevated compared to the norm population. We also did not detect any differences between the groups in the other outcomes. In this study, we could not detect effects of a preconception lifestyle intervention in obese infertile women on the cardiometabolic health of their offspring. Low follow-up rates, perhaps due to the children’s age or the subject matter, combined with selection bias abating contrast in periconceptional weight between participating mothers, hampered the detection of potential effects. Future studies that account for these factors are needed to confirm whether a preconception lifestyle intervention may improve the cardiometabolic health of children of obese mothers.

Causative Mechanisms of Childhood and Adolescent Obesity Leading to Adult Cardiometabolic Disease: A Literature Review

The past few decades have shown a worrisome increase in the prevalence of obesity and its related illnesses. This increasing burden has a noteworthy impact on overall worldwide mortality and morbidity, with significant economic implications as well. The same trend is apparent regarding pediatric obesity. This is a particularly concerning aspect when considering the well-established link between cardiovascular disease and obesity, and the fact that childhood obesity frequently leads to adult obesity. Moreover, most obese adults have a history of excess weight starting in childhood. In addition, given the cumulative character of both time and severity of exposure to obesity as a risk factor for associated diseases, the repercussions of obesity prevalence and related morbidity could be exponential in time. The purpose of this review is to outline key aspects regarding the current knowledge on childhood and adolescent obesity as a cardiometabolic risk factor, as well as the most common etiological pathways involved in the development of weight excess and associated cardiovascular and metabolic diseases.

The effects of a preschool-based intervention for Early Childhood Education and Care teachers in promoting healthy eating and physical activity in young children: A cluster randomised controlled trial

The need for excess weight gain prevention in disadvantaged young children is widely recognised. Early Childhood Education and Care teachers are potential key actors in early interventions to prevent overweight and obesity. This study examines the effects of a preschool-based intervention for teachers in promoting healthy eating and physical activity in young children. A cluster randomised controlled trial was conducted at 41 preschools in a deprived area of Amsterdam, The Netherlands. The intervention consisted of 2 programmes that were applied in succession: A Healthy Start and PLAYgrounds for TODdlers. The study period was 9 months. Primary outcomes were assessed via questionnaires and included teachers' knowledge, attitude, food/activity-related practices, and level of confidence in promoting healthy behaviours. Secondary outcomes in this study were teachers' and children's BMI (z-score), body composition, dietary intake and physical activity level. Intention-to-treat analyses were performed using linear mixed models. In total, 115 teachers and 249 children (mean age 3.0 (0.2) years) were included. A positive effect on teachers' knowledge about the Dutch dietary guidelines was found after the programme A Healthy Start (difference = 1.38; 1-sided 95% CL = 0.29; p = 0.02). This effect was not sustained at 9 months (difference = 0.34; 1-sided 95% CL = -0.76; p = 0.31). The overall intervention had a positive effect on 3 of the 5 attitude statements regarding a healthy lifestyle (difference ranged from 0.34 to 0.55) and on the practice scale Activity-related-Modelling (difference = 0.16; 1-sided 95% CL = 0.06; p = 0.01). No intervention effects were observed on food-related practice scales and the level of confidence in promoting healthy behaviours. At this stage, no effects were seen on teachers' and children's BMI (z-score). This study contributes to the professional development of Early Childhood Education and Care teachers and addresses the call for interventions to prevent overweight/obesity and to minimise health inequalities in young children.

New bioelectrical impedance analysis equations for children and adolescents based on the deuterium dilution technique

BACKGROUND AND AIMS

Body composition in childhood is not only a marker of the prevalence of obesity, but it can also be used to assess associated metabolic complications. Bioelectrical impedance analysis (BIA) shows promise as an easy to use, rapid, and non-invasive tool to evaluate body composition. The objectives of this study were to: (a) develop BIA prediction equations to estimate total body water (TBW) and fat-free mass (FFM) in European children and early adolescents and to validate the analysis with the deuterium dilution as the reference technique and (b) compare our results with previously published paediatric BIA equations.

METHODS

The cohort included 266 healthy children and adolescents between 7 and 14 years of age, 46% girls, in five European countries: Bosnia and Herzegovina, Latvia, Montenegro, North Macedonia, and Portugal. TBW and FFM were the target variables in the developed regression models. For model development, the dataset was randomly split into training and test sets, in 70:30 ratio, respectively. Model tuning was performed with 10-fold cross-validation that confirmed the unbiased estimate of its performance. The final regression models were retrained on the whole dataset.

RESULTS

Cross-validated regression models were developed using resistance index, weight, and sex as the optimal predictors. The new prediction equations explained 87% variability in both TBW and FFM. Limits of agreement between BIA and reference values, were within ±17% of the mean, (-3.4, 3.7) and (-4.5, 4.8) kg for TBW and FFM, respectively. BIA FFM and TBW estimates were within one standard deviation for approximately 83% of the children. BIA prediction equations underestimated TBW and FFM by 0.2 kg and 0.1 kg respectively with no proportional bias and comparable accuracy among different BMI-for-age subgroups. Comparison with predictive equations from published studies revealed varying discrepancy rates with the deuterium dilution measurements, with only two being equivalent to the equations developed in this study.

CONCLUSIONS

The small difference between deuterium dilution and BIA measurements validated by Bland-Altman analysis, supports the application of BIA for epidemiological studies in European children using the developed equations.

Preconception Lifestyle and Cardiovascular Health in the Offspring of Overweight and Obese Women

Women’s lifestyle has important implications for the development and health of their offspring. Yet little is known about the association between women’s preconception dietary intake and physical activity with cardiovascular health of the offspring. We therefore examined this association in a group of Dutch women with overweight or obesity (BMI ≥ 29 kg/m²) and infertility, who participated in a 6-month randomized preconception lifestyle intervention trial, and their offspring (n = 46). Preconception dietary intake and physical activity were assessed during the 6-month intervention using a food frequency questionnaire and the Short QUestionnaire to ASsess Health-enhancing physical activity (SQUASH), respectively. Offspring cardiovascular health (i.e., BMI, waist:height ratio, systolic and diastolic blood pressure, fat and fat free mass, and pulse wave velocity) was measured at age 3–6 years. Multivariable linear regression analyses were used to examine the associations between preconception lifestyle and offspring cardiovascular health. Higher preconception vegetable intake (per 10 g/day) was associated with lower offspring diastolic blood pressure (Z-score: −0.05 (−0.08; −0.01); p = 0.007) and higher preconception fruit intake (per 10 g/day) was associated with lower offspring pulse wave velocity (−0.05 m/s (−0.10; −0.01); p = 0.03). Against our expectations, higher preconception intake of sugary drinks was associated with a higher offspring fat free mass (0.54 kg (0.01; 1.07); p = 0.045). To conclude, preconception dietary intake is associated with offspring health.

The effects of intrauterine insemination and single embryo transfer or modified natural cycle in vitro fertilization on offspring's health-Follow-up of a randomized clinical trial

OBJECTIVE

Does ovarian hyperstimulation and/or the in vitro procedure of assisted reproduction affect neurodevelopmental and physical health of the offspring?

STUDY DESIGN

Infertile couples were randomly allocated to intrauterine insemination with controlled ovarian hyperstimulation (IUI-COH), modified natural cycle in vitro fertilization (IVF-MNC) or single embryo transfer IVF (IVF-SET). We compared neurodevelopmental and physical health in childhood (4-7 years). We used age-appropriate questionnaires to assess behavioral problems (Child Behavior Check List (CBCL)) and executive functioning (Behavior Rating Inventory of Executive Function (BRIEF)). We measured body mass index Z-score, waist- and hip-circumference, body fat percentage, blood pressure Z-scores, pulse wave velocity, glucose, insulin, insulin resistance, total cholesterol, high- and low-density lipoprotein cholesterol, triglycerides, and high sensitivity c-reactive protein. We compared groups by analysis of variance.

RESULTS

We examined 191 (57%) of the 333 children born in the study at a mean age of 5.5 years (range 4.0-7.6 years). We found no statistically significant differences between randomization groups in children's neurodevelopmental or physical health indices (all p-values > 0.05). Comparing the outcomes between actual method of conception, including a naturally conceived group, also did not show statistically significant differences.

CONCLUSIONS

Although this follow-up study was not powered on childhood outcomes and limited power due to attrition may have hampered detection of subtle effects, we found no indications of differences in neurodevelopmental and physical health between ovarian hyperstimulation and/or the in vitro procedure of assisted reproduction. Future trials should be powered on child outcomes, and aim to optimize follow-up rates to provide answers that are more definitive.

Factors affecting body composition in preterm infants: Assessment techniques and nutritional interventions

Limited research has been conducted that elucidates the growth and body composition of preterm infants. It is known that these infants do not necessarily achieve extra-utero growth rates and body composition similar to those of their term counterparts. Preterm infants, who have difficulty in achieving these growth rates, could suffer from growth failure. These infants display an increased intra-abdominal adiposity and abnormal body composition when they achieve catch-up growth. These factors affect the quality of weight gain, as these infants are not only shorter and lighter than term infants, they also have more fat mass (FM) and less fat-free mass (FFM), resulting in a higher total fat percentage. This could cause metabolic syndrome and cardiovascular problems to develop later in a preterm infant's life. The methods used to determine body composition in preterm infants should be simple, quick, non-invasive and inexpensive. Available literature was reviewed and the Dauncey anthropometric model, which includes skinfold thickness at two primary sites and nine body dimensions, is considered in this review the best method to accurately determine body composition in preterm infants, especially in resource-poor countries. It is imperative to accurately assess the quality of growth and body composition of this fragile population in order to determine whether currently prescribed nutritional interventions are beneficial to the overall nutritional status and quality of life-in the short- and long-term-of the preterm infant, and to enable timely implementation of appropriate interventions, if required.

A preschool-based intervention for Early Childhood Education and Care (ECEC) teachers in promoting healthy eating and physical activity in toddlers: study protocol of the cluster randomized controlled trial PreSchool@HealthyWeight

BACKGROUND

Interventions to prevent overweight and obesity in toddlers are needed to minimize health inequalities, especially in migration and lower socio-economic groups. Preschools are identified as important environments for interventions to prevent overweight and obesity. Early Childhood Education and Care (ECEC) teachers in preschools are potential key actors in promoting healthy eating and physical activity. This paper describes the research design of a Dutch preschool-based intervention for ECEC teachers in promoting healthy eating and physical activity in toddlers.

METHODS

PreSchool@HealthyWeight concerns a cluster randomized controlled trial on preschools in Amsterdam Nieuw-West, Netherlands. This city district is characterised by inhabitants with a migration background and low socio-economic status. Forty-one preschools, with 115 ECEC teachers and 249 toddlers/parents, were randomly allocated to an intervention or control group. An intervention for teachers will be carried out on intervention locations and consists of modified versions of 2 existing programs: 'A Healthy Start' and 'PLAYgrounds'. In 'A Healthy Start', ECEC teachers learn to provide a healthy and active environment for toddlers. The 'PLAYgrounds for Toddlers' program, coaches ECEC teachers to stimulate physical activity in the playgrounds of preschools. PreSchool@HealthyWeight aims to evaluate the effectiveness of the intervention after 9 months. Primary outcomes are the teachers' knowledge, attitude and practices concerning healthy eating and physical activity, and consequently the level of confidence of ECEC teachers in promoting healthy eating and physical activity in toddlers. Secondary outcomes include the Body Mass Index, body composition, dietary intake and physical activity level of teachers and toddlers. In addition, the activating role of ECEC teachers and the physical activity of toddlers on the playgrounds will be evaluated. Lastly, the knowledge, attitude and practices of parents concerning healthy eating and physical activity will be assessed.

DISCUSSION

It is hypothesized that this preschool-based intervention for ECEC teachers improves the knowledge, attitude and practices regarding healthy eating and physical activity, and consequently the level of confidence of ECEC teachers in promoting healthy eating and physical activity of toddlers. The intervention addresses the call for early intervention to prevent overweight and obesity and to minimize health inequalities.

TRIAL REGISTRATION

Netherlands Trial Register (NTR): NL5850 . Date registered: August 26, 2016.

Maternal Prepregnancy Overweight and Obesity Are Associated with Reduced Physical Fitness But Do Not Affect Physical Activity in Childhood: The Amsterdam Born Children and Their Development Study

BACKGROUND

Maternal overweight/obesity during pregnancy increases offspring's risks of obesity and cardiovascular disease (CVD). A possible pathway is by reduced physical fitness and physical activity (PA) levels in children of overweight/obese mother. We assessed whether maternal prepregnancy overweight/obesity independently determines cardiorespiratory fitness (CRF), muscular strength, moderate-to-vigorous physical activity (MVPA), and sedentary behavior (SB) in 8- to 9-year-old children. We also assessed whether child's fat mass (FM) mediates these associations.

METHODS

One hundred ninety-four children of Dutch ethnicity aged 8.6 (± 0.4) years were randomly selected from a prospective birth cohort, the Amsterdam Born Children and their Development (ABCD) study. CRF was assessed by the 20-m multistage shuttle run test (20-m MSRT), muscular strength by hand dynamometry, and MVPA and SB by accelerometry. The association of prepregnancy body mass index (BMI) ≥ 25 kg/m² with these outcome measures was assessed by multivariable linear regressions.

RESULTS

Mean (± standard deviation) attained 20-m MSRT stage was 5.3 (± 1.7). Compared with children from normal weight women, children of women with prepregnancy overweight/obesity attained a 0.80 (95% confidence interval: 0.15-1.50) lower stage, adjusted for child's sex and MVPA. This association was not mediated by birthweight or child's FM at age 5 years. Maternal prepregnancy overweight/obesity was not associated with child's muscular strength, MVPA, or SB.

CONCLUSIONS

Maternal prepregnancy overweight/obesity was associated with reduced childhood CRF, but not with muscular strength, PA, or SB. Birthweight and FM at age 5 years did not mediate this association. Reduced CRF may partly explain the increased CVD risk in children of overweight/obese women.

Adapting the ToyBox obesity prevention intervention for use in Scottish preschools: protocol for a feasibility cluster randomised controlled trial

INTRODUCTION

There is an increasing need for the adoption of effective preschool obesity prevention interventions to combat the high levels of early-childhood obesity in the UK. This study will examine the feasibility and acceptability of the adapted version of the ToyBox intervention-a preschool obesity prevention programme-for use in Scotland (ToyBox-Scotland). This will inform the design of a full-scale cluster randomised controlled trial (RCT).

METHODS AND ANALYSIS

The ToyBox-Scotland intervention will be evaluated using a feasibility cluster RCT, which involves children aged 3-5 years at six preschools in Glasgow, three randomly assigned to the intervention group and three to the usual-care control group. The original ToyBox intervention was adapted for the Scottish context using a coproduction approach. Within the 18-week intervention, physical activity and sedentary behaviour will be targeted in the preschool through environmental changes to the classroom, physical activity sessions and movement breaks. Parents will receive home activity packs every 3 weeks containing sticker incentives and interactive parent-child games that target sedentary behaviour, physical activity, eating/snacking and water consumption. As this is a feasibility study, parameters such as recruitment rates, attrition rates and SDs of outcome measures will be obtained which will inform a power calculation for a future RCT. Additional variables to be assessed include accelerometer-measured physical activity, sedentary behaviour and sleep, body mass index, home screen time, eating/snacking and water consumption. Outcomes will be assessed at baseline and 14-17 weeks later. Intervention fidelity will be assessed using questionnaires and interviews with parents and practitioners, observation and session delivery records.

ETHICS AND DISSEMINATION

This study was granted ethical approval by the University of Strathclyde's School of Psychological Sciences and Health Ethics Committee. Results will be disseminated through publication in peer-reviewed journals, presentation at conferences and in lay summaries provided to participants.

TRIAL REGISTRATION NUMBER

ISRCTN12831555.

Validity of bioelectrical impedance analysis in predicting total body water and adiposity among Senegalese school-aged children

Introduction

Childhood obesity is currently a serious public health challenge in developing countries. Therefore, an accurate assessment of adiposity is required. The objective of this study was to validate BIA prediction equations for the assessment of total body water and adiposity or percentage of body fat for the first time in Senegalese school-aged children.

Methods

One-hundred-fifty-one (151) pupils who were 8–11 years old were randomly selected from four public schools in Dakar. The body composition measured by deuterium dilution method (DDM) was used as the reference method and compared to that predicted by BIA using a multi-frequency analyser. Stepwise backward multiple linear regression was performed to calculate TBW and %BF in a subsample, which were then validated in the rest of the sample. The Bland and Altman approach was used to assess the agreement between the two methods (bias and limits of agreement).

Results

FFM was higher in boys (24.6±6.9 kg) compared to girls (21.2±3.3 kg; P<0.001), and FM was lower in boys: 3.7 kg [0.9–26.4] compared to girls: 4.5 kg [1.7–22.7]. Overall, 11.3% of children presented excess adiposity (%BF >25% in boys, and >30% in girls) and 2.0% were obese according to WHO cut points for obesity (BMI z-score >+2.0). The equations developed were as follows: TBW = 0.376(Height²/Z₅₀)-0.470 (sex) +0.076(weight) +0.065(height)-2.28.

%BF = -1.10(height²/Z₅₀) +3.14(sex)+1.57(weight)-4.347. These specific equations showed good precision and a low and non-significant mean bias (0.11 kg, P = 0.279; and 0.19 kg, P = 0.764) for TBW and %BF, respectively.

Conclusion

The newly developed equations can be used as an accurate and alternative screening tool for the assessment of obesity among children in various settings.

The effect of maternal HIV status and treatment duration on body composition of HIV-exposed and HIV-unexposed preterm, very and extremely low-birthweight infants

BACKGROUND

There is an evidence gap regarding the relationship between HIV exposure, body composition (and the quality thereof) and preterm infants.

AIM

This study determined the body composition of HIV-exposed, preterm very low-birthweight (VLBW) and extremely low-birthweight (ELBW) infants and to assess the effect of maternal HAART duration on the body composition of this vulnerable population.

METHODS

A descriptive cross-sectional study was conducted. HIV-exposed and -unexposed preterm infants (<37 weeks) with a birthweight of ≤1200g were included. Maternal medical background was recorded. Infant body composition measurements were recorded weekly during the 28-day follow-up period.

RESULTS

Thirty preterm infants (27%) were HIV-exposed. HIV-exposed infants had significantly (=0.01) lower gestational ages than HIV-unexposed infants (25-28 weeks). HIV-exposed infants had significantly lower measurements on day 21 and day 28 for triceps skinfold (TSF) (2.5 mm vs 2.7 mm, = 0.02 and 2.6 mm vs 2.9 mm, <0.01), subscapular skinfold (SSSF) (2.3 mm vs 2.6 mm, = 0.02 and 2.4 mm vs 2.7 mm, =<0.01) and fat mass percentage (FM%) (0.9% vs 1.4%, = 0.02 and 1.0% vs 1.5%, = 0.03). HIV-exposed infants whose mothers received HAART for ≥ 20 weeks were heavier and had a higher FM% and lower fat-free mass percentage (FFM%) at birth than HIV-exposed preterm infants whose mothers received highly active antiretroviral therapy for ≥ 4- < 20 weeks.

CONCLUSION

Mothers receiving HAART could have increased risk of preterm delivery, and the duration of maternal HAART affects postnatal body composition of their infants. Body composition differs between HIV-exposed and HIV-unexposed preterm infants.

Predictive validity of body fat percentage by bioimpedance compared with deuterium oxide dilution in Costa Rican schoolchildren

OBJECTIVE

The purpose of this study was to verify the validity of body fat percentage (BF%) by bioelectrical impedance analysis (BIA) in a sample of Costa Rican schoolchildren.

METHODS

The sample consisted of 52 male (mean age 8.1 ± 0.9 years) and 49 female (mean age 7.5 ± 1.0 years) schoolchildren. Deuterium oxide dilution was the reference method used as the "gold standard" to determine the fat mass (FM) expressed as BF%. Linear regression analyses and paired sample t-tests were used to test the association and mean differences between BIA and deuterium oxide dilution BF%. Concordance between BIA and deuterium oxide dilution BF% was determined by Lin's concordance correlation coefficient. Measurement of agreement between the two methods was analyzed using the Bland-Altman procedure.

RESULTS

Significant associations between BIA and deuterium oxide dilution BF% were found in males (R = 0.97, R²  = 0.95, P < .0001) and in females (R = 0.98, R²  = .96, P < .0001). The measurements of BF% (mean ± SD) were not significantly different between males (BIA 31.1 ± 7.6% vs. deuterium oxide dilution 31.0 ± 7.4%) and females (BIA 25.9 ± 7.9% vs. deuterium oxide dilution 26.3 ± 7.8%) by t-test. Lin's concordance correlation coefficient identified an almost perfect strength of agreement between males and females. Bland-Altman plots showed that the Bodystat measured similar BF% compared to the deuterium oxide dilution in both males and females.

CONCLUSIONS

BIA Bodystat presented high agreement with BF% measured by deuterium oxide dilution; therefore BIA Bodystat is recommended for estimating BF% in Costa Rican schoolchildren.

Maternal early pregnancy lipid profile and offspring's lipids and glycaemic control at age 5-6 years: The ABCD study

BACKGROUND & AIMS

Maternal early pregnancy lipid profile might influence offspring's lipids and glycaemic control, through an increased offspring's fat percentage. This explorative study investigates whether maternal early pregnancy lipid profile is associated with offspring's lipids and glycaemic control independently of offspring's fat percentage and if these associations are mediated by offspring's fat percentage. Possible sex differences in these associations are also examined.

METHODS

1133 mother-child pairs of the prospective ABCD-study were included. Maternal non-fasting lipids were collected in early pregnancy: triglycerides, total cholesterol (TC), Apolipoprotein A1 (ApoA1), Apolipoprotein B (ApoB) and free fatty acids (FFA). Fasting triglycerides, TC, high density lipoprotein (HDL), low density lipoprotein (LDL), glucose and C-peptide were assessed in offspring aged 5-6 years and HOMA2-IR was calculated.

RESULTS

After adjustment for covariates, strongest associations were found between maternal TC and offspring's TC (boys β(95%CI) = 0.141 (0.074-0.207); girls β(95%CI) = 0.268 (0.200; 0.336)) and LDL (boys β(95%CI) = 0.114 (0.052; 0.176); girls β(95%CI) = 0.247 (0.181-0.312)), maternal ApoB and offspring's TC (boys β(95%CI) = 0.638 (0.311-0.965); girls β(95%CI) = 1.121 (0.766-1.475)) and LDL (boys β(95%CI) = 0.699 (0.393-1.005); girls β(95%CI) = 1.198 (0.868-1.529)), and maternal ApoA1 and offspring's HDL (only boys β(95%CI) = 0.221 (0.101-0.341)). No significant association was found between maternal lipids and offspring's glycaemic control, and offspring's fat percentage played no mediating role.

CONCLUSIONS

Maternal early pregnancy lipid profile is associated with offspring's lipid profile in childhood, with overall stronger associations in girls. This study provides further evidence that lowering lipid levels during pregnancy might be beneficial for the long term health of the offspring.

The Association between Maternal 25-Hydroxyvitamin D Concentration during Gestation and Early Childhood Cardio-metabolic Outcomes: Is There Interaction with Pre-Pregnancy BMI?

Both maternal 25-hydroxyvitamin D(25OHD) status and pre-pregnancy BMI(pBMI) may influence offspring cardio-metabolic outcomes. Lower 25OHD concentrations have been observed in women with both low and high pBMIs, but the combined influence of pBMI and 25OHD on offspring cardio-metabolic outcomes is unknown. Therefore, this study investigated the role of pBMI in the association between maternal 25OHD concentration and cardio-metabolic outcomes in 5-6 year old children. Data were obtained from the ABCD cohort study and 1882 mother-child pairs were included. The offspring outcomes investigated were systolic and diastolic blood pressure, heart rate, BMI, body fat percentage(%BF), waist-to-height ratio, total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, glucose, C-peptide, and insulin resistance(HOMA2-IR). 62% of the C-peptide samples were below the detection limit and were thus imputed using survival analysis. Models were corrected for maternal and offspring covariates and tested for interaction with pBMI. Interaction with pBMI was observed in the associations with insulin resistance markers: in offspring of overweight mothers(≥25.0kg/m²), a 10 nmol/L increase in maternal 25OHD was associated with a 0.007(99%CI:-0.01,-0.001) nmol/L decrease in C-peptide and a 0.02(99%CI:-0.03,-0.004) decrease in HOMA2-IR. When only non-imputed data were analyzed, there was a trend for interaction in the relationship but the results lost significance. Interaction with pBMI was not observed for the other outcomes. A 10 nmol/L increase in maternal 25OHD was significantly associated with a 0.13%(99%CI:-0.3,-0.003) decrease in %BF after correction for maternal and child covariates. Thus, intrauterine exposure to both low 25OHD and maternal overweight may be associated with increased insulin resistance in offspring, while exposure to low 25OHD in utero may be associated with increased offspring %BF with no interactive effects from pBMI. Due to the limitations of this study, these results are not conclusive, however the observations of this study pose important research questions for future studies to investigate.

Do neighborhood characteristics in Amsterdam influence adiposity at preschool age?

Background: Neighborhood characteristics may contribute to adiposity in young children, but results in the current literature are inconsistent. This study aimed to investigate whether objective (socioeconomic status (SES)) and subjective (perceived safety, satisfaction with green spaces and perceived physical disorder) neighborhood characteristics directly influence child adiposity (as measured by BMI, percent body fat (%BF) and waist-to-height ratio (WHtR)). Methods: Data on child BMI, %BF and WHtR were obtained from the Amsterdam Born Children and their Development cohort at 5–6 years of age. Three thousand four hundred and sixty nine (3469) children were included in the analyses. Mixed models, using random intercepts for postal code area to account for neighborhood clustering effects, were used to analyze the relationships of interest. Results: Associations were observed for both perceived safety and neighborhood SES with %BF after adjustment for maternal education and ethnicity. All relationships were eliminated with the inclusion of individual covariates and parental BMI into the models. Conclusions: In general, child adiposity at age 5–6 years was not independently associated with neighborhood characteristics, although a small relationship between child %BF and both neighborhood SES and perceived safety cannot be ruled out. At this young age, familial and individual factors probably play a more important role in influencing child adiposity than neighborhood characteristics.

Associations of infant feeding and timing of linear growth and relative weight gain during early life with childhood body composition

BACKGROUND

Growth and feeding during infancy have been associated with later life body mass index. However, the associations of infant feeding, linear growth and weight gain relative to linear growth with separate components of body composition remain unclear.

METHODS

Of 5551 children with collected growth and infant-feeding data in a prospective cohort study (Amsterdam Born Children and their Development), body composition measured using bioelectrical impedance analysis at the age of 5-6 years was available for 2227 children. We assessed how feeding (duration of full breastfeeding and timing of introduction of complementary feeding) and conditional variables representing linear growth and relative weight gain were associated with childhood fat-free mass (FFM) and fat mass (FM).

RESULTS

Birth weight was positively associated with both FFM and FM in childhood, and more strongly with FFM than FM. Faster linear growth and faster relative weight gain at all ages in infancy were positively associated with childhood FFM and FM. The associations with FM were stronger for relative weight gain than for linear growth (FM z score: β coefficient 0.23 (95% con 0.19 to 0.26), P<0.001 and 0.14 (0.11 to 0.17), P<0.001 per s.d. change in relative weight gain and linear growth between 1 and 3 months, respectively). Compared with full breastfeeding <1 month, full breastfeeding >6 months was associated with lower FM (FM z score: -0.17 (-0.28 to -0.05), P=0.005) and lower FFM (FFM z score: -0.13 (-0.23 to -0.03), P=0.015), as was the introduction of complementary feeding >6 months (FM z score: -0.22 (-0.38 to -0.07), P=0.004), compared with <4 months.

CONCLUSIONS

Faster infant weight gain is associated with a healthier childhood body composition when it is caused by faster linear growth. Full breastfeeding >6 months and introduction of complementary feeding >6 months are associated with lower childhood FM.

Methodologies to assess paediatric adiposity

INTRODUCTION

Childhood obesity is associated with increased risk of adult obesity, cardiovascular disease, diabetes and cancer. Appropriate techniques for assessment of childhood adiposity are required to identify children at risk. The aim of this review was to examine core clinical measurements and more technical tools to assess paediatric adiposity.

METHODS

The online databases PubMed, CINALH and EMBASE were searched and the abstracts identified were reviewed to determine appropriate studies. Their reference lists were also searched to identify further eligible studies. Publications were included if they described childhood measurement techniques or involved validation.

RESULTS AND DISCUSSION

There are many body composition assessment tools available, none of which are direct. Each technique has limitations and a combination of methods may be used. The main clinical techniques are weight, height, body mass index (BMI) and circumferences which provide sufficient information to enable classification of overweight or obesity when growth centile charts and ratios are employed. Further investigation depends on resources available and examiner skill. Skinfold thicknesses are cost-effective but require technical training and only measure subcutaneous fat. Dual energy X-ray absorptiometry (DEXA), air displacement plethysmography (ADP), magnetic resonance imaging (MRI) and computed tomography (CT) are more costly and intensive, requiring the child to remain still for longer periods. DEXA and ADP are capable of accurately measuring adiposity but are unable to distinguish between fat depots. MRI and CT can distinguish intra-abdominal from subcutaneous adiposity and are considered gold standards, but CT is unsuitable for adiposity measurement in children due to high levels of radiation exposure. Ultrasound is a promising technique capable of measuring intra-abdominal adiposity in children but requires further validation.

CONCLUSION

The core clinical measurements of weight, height, BMI and circumferences are sufficient to enable diagnosis of paediatric overweight and obesity while more technical tools provide further insight.

BMI may underestimate the socioeconomic gradient in true obesity

BACKGROUND

Body mass index (BMI) does not make a distinction between fat mass and lean mass. In children, high fat mass appears to be associated with low maternal education, as well as low lean mass because maternal education is associated with physical activity. Therefore, BMI might underestimate true obesity in children of low-educated mothers.

OBJECTIVE

To investigate the associations of maternal education with fat mass index (FMI), lean mass index (LMI) and BMI.

METHODS

In total, 1965 Dutch children from a prospective cohort, aged 5.7 years (standard deviation 0.5), had available data on body composition based on bioelectrical impedance analysis.

RESULTS

Maternal education was not associated with BMI after adjustment for confounders. In contrast, children of low-educated mothers had a higher FMI (β 0.28 95% confidence interval [CI] 0.07; 0.49) and a lower LMI (β -0.18 95% CI -0.33; -0.03) compared with children of high-educated mothers.

CONCLUSIONS

This suggests that BMI underestimates the educational gradient of childhood obesity.

Bioimpedance prediction of fat-free mass from dual-energy X-ray absorptiometry in a multi-ethnic group of 2-year-old children

BACKGROUND/OBJECTIVES

Bioimpedance analysis (BIA) is a simple, convenient and widely used tool for the measurement of body composition in population surveys and surveillance. Prediction equations based on BIA applicable to preschool children are available but are based on total body water estimation and have not been developed across multiple ethnic groups. Our aim was to develop a BIA-based equation in a multi-ethnic sample of 2-year old using fat-free mass (FFM) from dual-energy X-ray absorptiometry (DXA) as criterion measure.

SUBJECTS/METHODS

Single-frequency hand-to-foot BIA (model BIM4, Impedimed) and whole-body DXA measurements were carried out in 77 (35 boys, 42 girls; 27 European, 20 Polynesian, 30 Asian and other) healthy preschool children (age range 22-38 months). Body mass index s.d. scores were 0.41 ± 1.23 for boys and 0.61 ± 1.09 for girls. The performance of published equations applicable to this age group was assessed. The predicted residual sum of squares method was used to develop and cross-validate a multiple regression equation relating FFM to BIA measures.

RESULTS

Published equations performed poorly for estimating FFM in this group of children. The prediction equation developed in all 77 children was: FFM (kg)=0.367 height(cm)(2)/resistance+0.188 weight (kg)+0.077 height (cm)+0.273 sex (male=1, female=0)-2.490, R(2)=0.89, standard error of estimate=0.50 kg. Ethnicity and age did not add significantly to the model.

CONCLUSIONS

We have developed an equation that may have application for prediction of FFM in 2-3-year-old children, which does not require determination of hydration factors. Further work should be carried out using DXA scanning to extend the applicable age range.

Association between body size and blood pressure in children from different ethnic origins

Objective

To assess associations between body size and blood pressure in children (5-6 years) from different ethnic origins.

Method

Five ethnic groups of the ABCD cohort were examined: Dutch (n=1 923), Turkish (n=99), Moroccan (n=187), Black-African (n=67) and Black-Caribbean (n=121). Data on body-mass-index (BMI), waist-to-height ratio (WHtR), fat-mass-index (FMI), and systolic blood pressure (SBP) and diastolic blood pressure (DBP), were collected. Linear regression analysis with restricted cubic splines was used to examine non-linear associations between body size and blood pressure, adjusted for age, sex, height and birth weight.

Results

Ethnic differences were found in associations of BMI with SBP and DBP (SBP: p=0.001 and DBP: p=0.01) and FMI with SBP (p=0.03). BMI and FMI had a relatively large positive association with SBP in Turkish children (BMI: β=2.46mmHg; 95%CI:1.20-3.72; FMI: β=2.41mmHg; 95%CI:1.09-3.73) compared to Dutch (BMI: β=1.31mmHg; 95%CI:0.71-1.92; FMI: β=0.84mmHg; 95%CI:0.23-1.45). Black-Caribbean and Moroccan children showed high blood pressure with low BMI and FMI. Moroccan children showed higher SBP with high BMI and FMI. WHtR was positively associated with SBP and DBP, similar in all ethnic groups. Generally, strongest associations with blood pressure were found for BMI in all ethnic groups.

Conclusion

Ethnic-specific associations between BMI, and FMI and blood pressure are present at young age, with Turkish children showing the highest increase in blood pressure with increasing body size. The higher blood pressure in the Black-Caribbean and Moroccan children with low BMI needs further research. WHtR or FMI do not seem to be associated more strongly to blood pressure than BMI in any ethnic group.