Sex differences in body composition early in life

Metabolic maturation in the infant urine during the first 3 months of life

The infant urine metabolome provides a body metabolic snapshot, and the sample collection can be done without stressing the fragile infant. 424 infant urine samples from 157 infants were sampled longitudinally at 1-, 2-, and 3 months of age. 49 metabolites were detected using proton nuclear magnetic resonance spectroscopy. Data were analyzed with multi- and univariate statistical methods to detect differences related to infant age-stage, gestational age, mother's pre-pregnancy BMI, C-section, infant birth weight, and infant sex. Significant differences were identified between age-stage (pbonferoni < 0.05) in 30% (15/49) of the detected metabolites. Urine creatinine increased significantly from 1 to 3 months. In addition, myo-inositol, taurine, methionine, and glucose seem to have conserved levels within the individual over time. We calculated a urine metabolic maturation age and found that the metabolic age at 3 months is negatively correlated to weight at 1 year. These results demonstrate that the metabolic maturation can be observed in urine metabolome with implications on infant growth and specifically suggesting that the systematic age effect on creatinine promotes caution in using this as normalization of other urine metabolites.

Polybrominated diphenyl ether (PBDE) exposure and adverse maternal and infant health outcomes: Systematic review

Polybrominated diphenyl ethers (PBDEs) are flame retardants found in ambient environment and are measured in humans. There are reports on general PBDE toxicity, including endocrine disrupting properties. Studies on adverse maternal and infant outcomes and underlying toxicity mechanisms needs to be understood. The objective of this study was to conduct a systematic review to examine the state of science on the relationship between PBDE and adverse maternal/infant health outcomes and related maternal biomarker changes. This literature review was conducted using PubMed, Scopus, Embase and Web of Science for published articles from January 2005-February 2022. Article quality was assessed using Newcastle-Ottawa Scale. Of the 1518 articles, only 54 human observational studies were screened in for this review. A second reviewer examined the validity of these articles. Reports on associations between PBDE and maternal health outcomes included gestational hypertension/preeclampsia (N = 2) and gestational diabetes mellitus/glycemic index (N = 6). Meanwhile, reports on PBDE and infant outcomes (N=32) included effects on infant birth weight, birth length and cephalic perimeter, preterm birth, fetal growth restriction and APGAR scores. Although findings on PBDE exposure and adverse infant outcomes showed inconsistencies across studies, in general, negative correlations between maternal PBDEs and infant birth weight, birth length and cephalic perimeter were seen, in few cases, after stratification by sex. Association between maternal PBDE and maternal biomarkers (N=18) suggested negative impact of PBDE exposure on markers relevant to neuro-endocrine system and inflammatory processes. The review findings identified potential associations between maternal PBDE and adverse maternal/infant health outcomes. Furthermore, PBDE-related biomarker changes suggest disturbances in maternal mechanisms relevant to endocrine disrupting properties of PBDEs. The observed study heterogeneity can be attributed to factors namely, sample size, study design and statistical analysis. Overall review findings imply the necessity for further research to validate PBDE exposure-related adverse maternal/infant health effects and to validate underlying toxicity mechanisms.

Gestational diabetes mellitus and size at birth modify early adiposity accretion. Evidence from the OBESO cohort

AIM

To evaluate the association between maternal obesity, gestational diabetes (GDM), and birth size with infant fat-mass (FM) accretion from 1 to 6 months (M).

METHODS

Healthy pregnant women and their term babies from the OBESO cohort were studied (1 M-3 M, n = 122; 1 M-6 M, n = 90). Registered maternal data was: pregestational body-mass-index (preBMI), GDM (2hOGTT), medications, gestational weight gain. Macrosomia (>4000 g), large/small for gestational age (LGA/SGA)(weight/age > 90° and < 90°, respectively-WHO) were recorded at birth. Infant FM (air-displacement plethysmography) was measured (1 M, 3 M, 6 M) and FM accretion computed (ΔkgFM from 1 M-3 M and 1 M-6 M). Exclusive breastfeeding (EBF) was assessed. Adjusted-multiple linear regression models were performed.

RESULTS

PreBMI was 27.4 ± 5.2 kg/m2. GDM was present in9%(n = 11) of women; 12.3%(n = 15) of them received metformin/insulin. One newborn was LGA; 20.7%(n = 25) were SGA. From 1 M-3 M, SGA was a predictor of higher FM accretion (B:0.28, 95%CI:0.14-0.43); GDM was not associated. From 1 M-6 M, higher FM accretion was observed in SGA newborns (B:0.43, 95%CI:0.19-0.67) and GDM infants (B:0.48, 95%CI:0.06-0.89). In all models (R2 ≥ 0.48, p < 0.001), infant weight and being female were positively associated, while maternal obesity, metformin/insulin, and EBF were not.

CONCLUSIONS

GDM appears to program early higher adiposity accretion, independently of excessive fetal growth. SGA was associated with higher FM accretion in early infancy.

Association between obesity and fecundity in patients undergoing intrauterine insemination

Objective

To determine if an association exists between body mass index (BMI) and fecundity after intrauterine insemination (IUI).

Design

Retrospective cohort study.

Setting

Academic-based fertility clinic.

Patients

Patients undergoing IUI July 2007 to May 2012.

Interventions

None.

Main Outcome Measures

Primary outcome: live-birth rate (LBR) per IUI cycle; secondary outcomes: positive pregnancy test and clinical pregnancy rates (CPRs).

Results

A total of 1959 cycles were performed on 661 women (mean age, 31.9 ± 4.9 years). When examined by obesity class, LBR and CPR were similar for women with class I, II, and III obesity when compared with women with normal BMI. However, class III obese women (adjusted risk ratio [aRR], 1.70; 95% confidence interval [CI], 1.12-2.59) had increased pregnancy rates compared with normal BMI, but no differences in pregnancy rates were observed for women with class I or II obesity. In addition, pregnancy rates (aRR, 1.50; 95% CI, 1.12-2.02) and CPR (aRR, 1.51; 95% CI, 1.07-2.14) were higher in overweight women relative to normal BMI. Notably, among patients with ovulatory dysfunction, CPRs after IUI were reduced by 43% in obese women (aRR, 0.57; 95% CI, 0.37-1.07), whereas women without ovulatory dysfunction were twice as likely to achieve a clinical pregnancy when they were obese (aRR, 1.96; 95% CI, 1.19-3.24). The CIs for the obesity risk ratios in each stratum of ovulatory function exhibited no overlap, suggesting evidence of potential effect modification by ovulatory function.

Conclusions

LBRs after IUI were similar across BMI subgroups. This is in contrast to research of in vitro fertilization treatments showing lower LBR with increasing BMI. However, obesity may adversely affect IUI CPR in those with ovulatory dysfunction in particular. The reason for this discrepancy is unclear and warrants further study.

Maternal Prenatal Factors and Child Adiposity in Associations with Cardiometabolic Risk Factors in Term-Born Chinese Children at the Age of 2 Years

Early growth has long-lasting associations with adult metabolic health. However, the association of adiposity with cardiometabolic risk factors in toddlers remains poorly understood. This study aimed to examine the association of maternal prenatal factors and child adiposity with child cardiometabolic risk factors among boys and girls aged 2 years. This was a birth cohort study of 549 term-born children in Shanghai, China, with follow-up data at the age of 2-years. Child anthropometric and adiposity measurements included weight, length, and skinfold thickness (triceps, subscapular, and abdominal). Child cardiometabolic risk factors included random morning plasma glucose, serum insulin, lipids, and systolic and diastolic blood pressure (SBP, DBP). At 2 years, overweight/obesity (weight-for-length z score, ZWFL > 2) was associated with 12.6 (95%CI 7.7, 17.4) mmHg higher SBP, and 7.9 (4.1, 11.8) mmHg higher DBP in boys, with similar results observed in girls. Maternal hypertensive disorders of pregnancy were associated with 3.0 (0.1, 5.8) higher SBP, 3.17 (0.90, 5.44) mmHg higher DBP, 0.24 (0.01,0.47) mmol/L higher plasma glucose, and 0.26 (0.01,0.51) mmol/L higher serum triglycerides after adjustment for child age, sex, and ZWFL. Maternal hypertensive disorders of pregnancy and child overweight/obesity were associated with higher SBP and DBP at the age of 2 years.

Development and validation of anthropometric-based fat-mass prediction equations using air displacement plethysmography in Mexican infants

BACKGROUND/OBJECTIVES

Fat-mass (FM) assessment since birth using valid methodologies is crucial since excessive adiposity represents a risk factor for adverse metabolic outcomes.

AIM

To develop infant FM prediction equations using anthropometry and validate them against air-displacement plethysmography (ADP).

SUBJECTS/METHODS

Clinical, anthropometric (weight, length, body-mass index -BMI-, circumferences, and skinfolds), and FM (ADP) data were collected from healthy-term infants at 1 (n = 133), 3 (n = 105), and 6 (n = 101) months enrolled in the OBESO perinatal cohort (Mexico City). FM prediction models were developed in 3 steps: 1) Variable Selection (LASSO regression), 2) Model behavior evaluation (12-fold cross-validation, using Theil-Sen regressions), and 3) Final model evaluation (Bland-Altman plots, Deming regression).

RESULTS

Relevant variables in the FM prediction models included BMI, circumferences (waist, thigh, and calf), and skinfolds (waist, triceps, subscapular, thigh, and calf). The R2 of each model was 1 M: 0.54, 3 M: 0.69, 6 M: 0.63. Predicted FM showed high correlation values (r ≥ 0.73, p < 0.001) with FM measured with ADP. There were no significant differences between predicted vs measured FM (1 M: 0.62 vs 0.6; 3 M: 1.2 vs 1.35; 6 M: 1.65 vs 1.76 kg; p > 0.05). Bias were: 1 M -0.021 (95%CI: -0.050 to 0.008), 3 M: 0.014 (95%CI: 0.090-0.195), 6 M: 0.108 (95%CI: 0.046-0.169).

CONCLUSION

Anthropometry-based prediction equations are inexpensive and represent a more accessible method to estimate body composition. The proposed equations are useful for evaluating FM in Mexican infants.

Early growth and body composition assessed by air displacement plethysmography in infants born with simple gastroschisis

BACKGROUND

Gastroschisis is an abdominal wall malformation usually associated with impaired growth.

OBJECTIVE

To evaluate the growth and body composition of infants born with simple gastroschisis in a referral center.

METHODS

This was a single-center, prospective case series of infants with simple gastroschisis who were measured at birth, at discharge, and at 3 months. Body composition was assessed via air-displacement plethysmography at discharge and at 3 months. The results were compared with those reported for healthy infants at an equivalent gestational age.

RESULTS

Simple gastroschisis infants were lighter and smaller at birth and remained similar at 3 months. All anthropometric z scores decreased from birth to discharge, followed by an increase but not a full recovery toward 3 months. Overall, gastroschisis infants had a similar FM percentage, FM% (11.1 ± 4.7), but a lower FFM, FFM (2481 ± 478 g), at discharge. FM% (18.5 ± 5.3) decreased at 3 months, and FFM remained lower (3788 ± 722 g) but improved between the two exams. Boys had significantly more FFM than girls at both evaluations. The multiple regression analysis showed that male sex, prematurity, total parenteral nutrition duration, and exclusive breast milk diets were associated with differences in body composition.

CONCLUSIONS

Infants with simple gastroschisis cared for in a referral center experienced growth failure at discharge and showed a similar FM% but lower FFM than healthy infants. At 3 months, they exhibited smaller FM% and FFM, but FFM improved after the first exam, representing a better protein accretion.

TYPE OF STUDY

Prognostic.

LEVEL OF EVIDENCE

IV.

Are Fat Mass and Lean Mass Associated with Grip Strength in Adolescents?

Background: The interaction between lean body mass (LBM) and fat mass index (FMI) with grip strength (GS) has not been explored in the same analysis model in adolescents. This study thus aims to analyze the association between FMI and LBM with GS. Methods: This cross-sectional study was conducted with data from the 2016 follow-up of the 1997/98 Birth Cohort of São Luís. Grip strength was assessed by the Jamar Plus + dynamometer. The LBM and FMI indexes were assessed [ratio of the mass (lean or fat-kg) to height (m2)]. The confounding variables identified for the relationship between FMI and LBM with GS in the same analysis model, by directed acyclic graph (DAG), were sex, age, race, work, alcohol consumption, smoking, physical activity, and consumption of ultra-processed foods and culinary preparations, used in the adjusted analysis. Results: A total of 2339 adolescents (52.5% girls) were analyzed. The boys have a higher GS than the girls. In the adjusted analysis, with each increase of 1 kg/m2 in the FMI, GS was reduced by 0.72 kgf for boys and 0.35 kgf for girls. At each increase of 1 kg/m2 in the LBM, GS increased by 2.18 kgf for boys and 1.26 kgf for girls. Conclusions: FMI was associated with lower GS regardless of the LBM. LBM was associated with higher GS regardless of the FMI.

Maternal excess adiposity and serum 25-hydroxyvitamin D < 50 nmol/L are associated with elevated whole body fat mass in healthy breastfed neonates

BACKGROUND

Vitamin D status of pregnant women is associated with body composition of the offspring. The objective of this study was to assess whether the association between maternal vitamin D status and neonatal adiposity is modified by maternal adiposity preconception.

METHODS

Healthy mothers and their term appropriate weight for gestational age (AGA) infants (n = 142; 59% male, Greater Montreal, March 2016-2019) were studied at birth and 1 month postpartum (2-6 weeks). Newborn (24-36 h) serum was collected to measure total 25-hydroxyvitamin D [25(OH)D] (immunoassay); maternal pre-pregnancy BMI was obtained from the medical record. Anthropometry, body composition (dual-energy X-ray absorptiometry) and serum 25(OH)D were measured at 2-6 weeks postpartum in mothers and infants. Mothers were grouped into 4 categories based on their vitamin D status (sufficient 25(OH)D ≥ 50 nmol/L vs. at risk of being insufficient < 50 nmol/L) and pre-pregnancy BMI (< 25 vs. ≥25 kg/m2): insufficient-recommended weight (I-RW, n = 24); insufficient-overweight/obese (I-OW/O, n = 21); sufficient-recommended weight (S-RW, n = 69); and sufficient-overweight/obese (S-OW/O, n = 28). Partial correlation and linear fixed effects model were used while adjusting for covariates.

RESULTS

At birth, infant serum 25(OH)D mean concentrations were below 50 nmol/L, the cut-point for sufficiency, for both maternal pre-pregnancy BMI categories; 47.8 [95%CI: 43.8, 51.9] nmol/L if BMI < 25 kg/m2 and 38.1 [95%CI: 33.5, 42.7] nmol/L if BMI ≥25 kg/m2. Infant serum 25(OH)D concentrations at birth (r = 0.77; P < 0.0001) and 1 month (r = 0.59, P < 0.0001) were positively correlated with maternal postpartum serum 25(OH)D concentrations. Maternal serum 25(OH)D concentration was weakly correlated with maternal percent whole body fat mass (r = - 0.26, P = 0.002). Infants of mothers in I-OW/O had higher fat mass versus those of mothers in S-OW/O (914.0 [95%CI: 766.4, 1061.6] vs. 780.7 [95%CI: 659.3, 902.0] g; effect size [Hedges' g: 0.42]; P = 0.04 adjusting for covariates) with magnitude of difference of 220.4 g or ~ 28% difference.

CONCLUSIONS

Maternal and neonatal vitamin D status are positively correlated. In this study, maternal adiposity and serum 25(OH)D < 50 nmol/L are dual exposures for neonatal adiposity. These findings reinforce the importance of vitamin D supplementation early in infancy irrespective of vitamin D stores acquired in utero and maternal weight status.

Anthropometrics and fat mass, but not fat-free mass, are compromised in infants requiring parenteral nutrition after neonatal intestinal surgery

BACKGROUND

Children with intestinal failure (IF) receiving long-term parenteral nutrition (PN) have altered body composition (BC), but data on BC changes from start of PN onwards are lacking.

OBJECTIVES

We aimed to assess growth and BC in infants after neonatal intestinal surgery necessitating PN and at risk of IF, and to explore associations with clinical parameters.

METHODS

A prospective cohort study in infants after intestinal surgery. IF was defined as PN dependency for >60 d. SD scores (SDS) for anthropometry were calculated until 6-mo corrected age. In a subgroup, fat mass (FM) and fat-free mass (FFM) were measured with air-displacement plethysmography at 2- and 6-mo corrected age. SDS for length-adjusted FM index and FFM index were calculated. Associations between cumulative amount of PN and BC parameters were analyzed with linear mixed-effect models.

RESULTS

Ninety-five neonates were included (54% male, 35% born <32 wk) and 39 infants (41%) had IF. Studied infants had compromised anthropometric parameters during follow-up. At 6-mo corrected age, they remained smaller (median weight-for-age SDS -0.9 [IQR -1.5, 0.1], P < 0.001) than the normal population. In 57 infants, 93 BC measurements were performed. FM index SDS was lower than in healthy infants at 2- and 6-mo corrected age (-0.9 [-1.6, -0.3], P < 0.001 and -0.7 [-1.3, 0.1], P = 0.001, respectively), but FFM index SDS did not differ. A higher cumulative amount of PN predicted a higher FM index in female infants but lower FM index in male infants.

CONCLUSIONS

In this cohort of infants receiving PN after intestinal surgery, compromised anthropometrics, decreased FM, and adequate FFM were observed during the first 6 mo. Male and female infants seemed to respond differently to PN when it comes to FM index. Continuing growth monitoring after the age of 6 mo is strongly recommended, and further research should explore the benefit of incorporating ongoing BC monitoring during follow-up.

Maternal Dietary Intake of Total Fat, Saturated Fat, and Added Sugar Is Associated with Infant Adiposity and Weight Status at 6 mo of Age

BACKGROUND

Whether current dietary guidelines are appropriate for pregnancy and lactation has not been well studied. Many women of reproductive age are not meeting recommendations for dietary components such as fat, added sugar, and fiber.

OBJECTIVES

To assess associations between maternal dietary components during pregnancy and lactation and infant growth and adiposity at 6 mo of age.

METHODS

Mother-infant dyads (n = 349) from the prospective, observational Mothers and Infants Linked for Healthy Growth study were included (100% fully breastfed for 1 mo; 75% to 6 mo). Daily intake of fat, fiber, and added sugar was obtained using the National Cancer Institute Diet History Questionnaire II during the third trimester of pregnancy and at 1 and 3 mo postpartum. Furthermore, intakes were categorized as meeting/exceeding 2015-2020 Dietary Guidelines for Americans. Multiple linear regression models adjusted for numerous potential confounders tested relations between dietary components and infant adiposity (via DXA) and growth parameters. Regression coefficients (β) for continuous variables were expressed per SD to allow for comparison of effect sizes.

RESULTS

Maternal intake of total fat and saturated fat was positively associated with infant percent body fat (%BF) (β: 0.84 per SD, P = 0.04; β: 0.96 per SD, P = 0.01, respectively). Added sugar intake was positively associated with infant weight-for-length z score (β: 0.16 per SD, P = 0.02), and excessive added sugar intake was positively associated with %BF at 6 mo (β: 0.75 per SD, P = 0.05).

CONCLUSIONS

In a predominantly fully breastfeeding cohort of women, maternal intake of fat and added sugar during pregnancy and lactation were associated with small increases in infant adiposity and relative weight at 6 mo. Additional research is needed to determine if these relations persist later in infancy and if such elevations in adiposity are important for long-term obesity risk.

Developmental programming of offspring adipose tissue biology and obesity risk

Obesity is reaching epidemic proportions and imposes major negative health crises and an economic burden in both high and low income countries. The multifaceted nature of obesity represents a major health challenge, with obesity affecting a variety of different organs and increases the risk of many other noncommunicable diseases, such as type 2 diabetes, fatty liver disease, dementia, cardiovascular diseases, and even cancer. The defining organ of obesity is the adipose tissue, highlighting the need to more comprehensively understand the development and biology of this tissue to understand the pathogenesis of obesity. Adipose tissue is a miscellaneous and highly plastic endocrine organ. It comes in many different sizes and shades and is distributed throughout many different locations in the body. Though its development begins prenatally, quite uniquely, it has the capacity for unlimited growth throughout adulthood. Adipose tissue is also a highly sexually dimorphic tissue, patterning men and women in different ways, which means the risks associated with obesity are also sexually dimorphic. Recent studies show that environmental factors during prenatal and early stages of postnatal development have the capacity to programme the structure and function of adipose tissue, with implications for the development of obesity. This review summarizes the evidence for a role for early environmental factors, such as maternal malnutrition, hypoxia, and exposure to excess hormones and endocrine disruptors during gestation in the programming of adipose tissue and obesity in the offspring. We will also discuss the complexity of studying adipose tissue biology and the importance of appreciating nuances in adipose tissue, such as sexual dimorphism and divergent responses to metabolic and endocrine stimuli. Given the rising levels of obesity worldwide, understanding how environmental conditions in early life affects adipose tissue phenotype and the subsequent development of obesity is of absolute importance.

Human Milk Exosomal MicroRNA: Associations with Maternal Overweight/Obesity and Infant Body Composition at 1 Month of Life

Among all the body fluids, breast milk is one of the richest sources of microRNAs (miRNAs). MiRNAs packaged within the milk exosomes are bioavailable to breastfeeding infants. The role of miRNAs in determining infant growth and the impact of maternal overweight/obesity on human milk (HM) miRNAs is poorly understood. The objectives of this study were to examine the impact of maternal overweight/obesity on select miRNAs (miR-148a, miR-30b, miR-29a, miR-29b, miR-let-7a and miR-32) involved in adipogenesis and glucose metabolism and to examine the relationship of these miRNAs with measures of infant body composition in the first 6 months of life. Milk samples were collected from a cohort of 60 mothers (30 normal-weight [NW] and 30 overweight [OW]/obese [OB]) at 1-month and a subset of 48 of these at 3 months of lactation. Relative abundance of miRNA was determined using real-time PCR. The associations between the miRNAs of interest and infant weight and body composition at one, three, and six months were examined after adjusting for infant gestational age, birth weight, and sex. The abundance of miR-148a and miR-30b was lower by 30% and 42%, respectively, in the OW/OB group than in the NW group at 1 month. miR-148a was negatively associated with infant weight, fat mass, and fat free mass, while miR-30b was positively associated with infant weight, percent body fat, and fat mass at 1 month. Maternal obesity is negatively associated with the content of select miRNAs in human milk. An association of specific miRNAs with infant body composition was observed during the first month of life, suggesting a potential role in the infant's adaptation to enteral nutrition.

Influence of gestational and perinatal factors on body composition of full-term newborns

OBJECTIVE

To evaluate the influence of gestational and perinatal factors on body composition and birth weight of full-term newborns.

METHOD

This was a cross-sectional study, within a prospective cohort, consisting of 124 postpartum women and their newborns. Data included the following: maternal age; ethnicity; pre-gestational body mass index; gestational weight gain; parity; gestational morbidities (hypertension and gestational diabetes mellitus); gestational age at birth; birth weight; and newborn's gender. Anthropometric and body composition data of the newborns were collected using air-displacement plethysmography (PeaPod® Infant Body Composition System-LMI; Concord, CA, USA). The stepwise technique was applied to a multiple linear regression model.

RESULTS

The significant variables in the model that explained 84% of the variation in neonatal fat-free mass were: birth weight; maternal age; newborn's gender and gestational age. For body fat mass: birth weight; newborn's gender; gestational arterial hypertension; gestational diabetes; and gestational weight gain. These variables explained 60% and 46% of fat mass, in grams and as a percentage, respectively. Regarding birth weight, the significant factors were gestational age, pre-gestational BMI, and gestational weight gain. Female newborns showed higher body fat mass and male newborns had higher fat-free mass.

CONCLUSION

Gestational and perinatal factors influence neonatal body composition. Early identification of these gestational factors, which may be modifiable, is necessary to prevent obesity and chronic noncommunicable diseases in the future.

Effect of maternal nutrient intake during 31-37 weeks gestation on offspring body composition in Samoa

BACKGROUND

Pregnancy dietary intake may be associated with newborn body composition, a predictor of future obesity. In Samoa, an energy-dense diet contributes to an alarming prevalence of adult obesity. Identifying associations between pregnancy nutrition and infant body composition in this setting may guide strategies to mitigate intergenerational transmission of obesity risk.

AIM

To examine dietary macro- and micronutrient intake of Samoan women during the third trimester of pregnancy and associations with infant body composition.

SUBJECTS AND METHODS

At 34-41 weeks of gestation, we measured dietary intake from the prior month using a Food Frequency Questionnaire (FFQ). Dual-energy X-ray absorptiometry (DXA) measured infant body composition at 1-14 days. We used multivariable linear regression models accounting for confounders to identify independent effects of nutrient intake on infant body composition.

RESULTS

After adjusting for maternal body mass index, age, gravidity, infant age, and sex, a respective 0.2 g increase and 0.2 g decrease in infant bone mass was associated with fibre and saturated fat intake. Increased protein intake was associated with 0.02 g decrease in bone mass.

CONCLUSIONS

While maternal dietary intake was not associated with infant adiposity or lean mass, we observed an effect on bone mass whose role in regulating metabolic health is overlooked.

Body composition and neuromotor development in the year after NICU discharge in premature infants

BACKGROUND

Hypothesis: neuromotor development correlates to body composition over the first year of life in prematurely born infants and can be influenced by enhancing motor activity.

METHODS

Forty-six female and 53 male infants [27 ± 1.8 (sd) weeks] randomized to comparison or exercise group (caregiver provided 15-20 min daily of developmentally appropriate motor activities) completed the year-long study. Body composition [lean body and fat mass (LBM, FM)], growth/inflammation predictive biomarkers, and Alberta Infant Motor Scale (AIMS) were assessed.

RESULTS

AIMS at 1 year correlated with LBM (r = 0.32, p < 0.001) in the whole cohort. However, there was no effect of the intervention. LBM increased by ~3685 g (p < 0.001)); insulin-like growth factor-1 (IGF-1) was correlated with LBM (r = 0.36, p = 0.002). IL-1RA (an inflammatory biomarker) decreased (-75%, p < 0.0125). LBM and bone mineral density were significantly lower and IGF-1 higher in the females at 1 year.

CONCLUSIONS

We found an association between neuromotor development and LBM suggesting that motor activity may influence LBM. Our particular intervention was ineffective. Whether activities provided largely by caregivers to enhance motor activity in prematurely born infants can affect the interrelated (1) balance of growth and inflammation mediators, (2) neuromotor development, (3) sexual dimorphism, and/or (4) body composition early in life remains unknown.

Effects of a modestly lower carbohydrate diet in gestational diabetes: a randomized controlled trial

BACKGROUND

Lower carbohydrate diets have the potential to improve glycemia but may increase ketonemia in women with gestational diabetes (GDM). We hypothesized that modestly lower carbohydrate intake would not increase ketonemia.

OBJECTIVE

To compare blood ketone concentration, risk of ketonemia, and pregnancy outcomes in women with GDM randomly assigned to a lower carbohydrate diet or routine care.

METHODS

Forty-six women aged (mean ± SEM) 33.3 ± 0.6 y and prepregnancy BMI 26.8 ± 0.9 kg/m2 were randomly assigned at 28.5 ± 0.4 wk to a modestly lower carbohydrate diet (MLC, ∼135 g/d carbohydrate) or routine care (RC, ∼200 g/d) for 6 wk. Blood ketones were ascertained by finger prick test strips and 3-d food diaries were collected at baseline and end of the intervention.

RESULTS

There were no detectable differences in blood ketones between completers in the MLC group compared with the RC group (0.1 ± 0.0 compared with 0.1 ± 0.0 mmol/L, n = 33, P = 0.31, respectively), even though carbohydrate and total energy intake were significantly lower in the intervention group (carbohydrate 165 ± 7 compared with 190 ± 9 g, P = 0.04; energy 7040 ± 240 compared with 8230 ± 320 kJ, P <0.01, respectively). Only 20% of participants in the MLC group met the target intake compared with 65% in the RC group (P <0.01). There were no differences in birth weight, rate of large-for-gestational-age infants, percent fat mass, or fat-free mass between groups.

CONCLUSIONS

An intervention to reduce carbohydrate intake in GDM did not raise ketones to clinical significance, possibly because the target of 135 g/d was difficult to achieve in pregnancy. Feeding studies with food provision may be needed to assess the benefits and risks of low-carbohydrate diets. This trial was registered at www.anzctr.org.au as ACTRN12616000018415.

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.

The Thin But Fat Phenotype is Uncommon at Birth in Indian Babies

BACKGROUND

Indian babies are hypothesized to be born thin but fat. This has not been confirmed with precise measurements at birth. If it is true, it could track into later life and confer risk of noncommunicable diseases (NCDs).

OBJECTIVES

Primarily, to accurately measure percentage of body fat (%BF) and body cell mass (BCM) in Indian babies with normal birth weight, compare them across different gestational ages and sex, and test the hypothesis of the thin but fat phenotype in Indian babies. Secondarily, to examine the relation between body weight and body fat in Indian babies.

METHODS

Term newborns (n = 156) weighing ≥2500 g, from middle socioeconomic status mothers were recruited in Bengaluru, India, and their anthropometry, %BF (air displacement plethysmography), and BCM (whole-body potassium counter) were measured. Maternal demography and anthropometry were recorded. The mean %BF and its dispersion were compared with earlier studies. The relation between newborn %BF and body weight was explored by regression analysis.

RESULTS

Mean birth weight was 3.0 ± 0.3 kg, with mean %BF 9.8 ± 3.5%, which was comparable to pooled estimates of %BF from published studies (9.8%; 95% CI: 9.7, 10.0; P > 0.05). Appropriate-for-gestational age (AGA) babies had higher %BF (1.8%) compared to small-for-gestational age (SGA) babies (P < 0.01). Mean %BCM of all babies at birth was 35.4 ± 10.5%; AGA babies had higher %BCM compared to SGA babies (7.0%, P < 0.05). Girls in comparison to boys had significantly higher %BF and lower %BCM. Body weight was positively associated with %BF.

CONCLUSION

Indian babies with normal birth weight did not demonstrate the thin but fat phenotype. Body weight and fat had positive correlation, such that SGA babies did not show a preservation of their %BF. These findings will have relevance in planning optimal interventions during early childhood to prevent NCDs risk in adult life.

Sex-specific relationships between early nutrition and neurodevelopment in preterm infants

BACKGROUND

Although early nutrition is associated with neurodevelopmental outcome at 2 years' corrected age in children born very preterm, it is not clear if these associations are different in girls and boys.

METHODS

Retrospective cohort study of infants born <30 weeks' gestational age or <1500 g birth weight in Auckland, NZ. Macronutrient, energy and fluid volumes per kg per day were calculated from daily nutritional intakes and averaged over days 1-7 (week 1) and 1-28 (month 1). Primary outcome was survival without neurodevelopmental impairment at 2 years corrected age.

RESULTS

More girls (215/478) survived without neurodevelopmental impairment at 2 years (82% vs. 72%, P = 0.02). Overall, survival without neurodevelopmental impairment was positively associated with more energy, fat, and enteral feeds in week 1, and more energy and enteral feeds in month 1 (P = 0.005-0.03), but all with sex interactions (P = 0.008-0.02). In girls but not boys, survival without neurodevelopmental impairment was positively associated with week 1 total intakes of fat (OR(95% CI) for highest vs. lowest intake quartile 62.6(6.6-1618.1), P < 0.001), energy (22.9(2.6-542.0), P = 0.03) and enteral feeds (1.9 × 10⁹(9.5-not estimable), P < 0.001).

CONCLUSIONS

Higher early fat and enteral feed intakes are associated with improved outcome in girls, but not boys. Future research should determine sex-specific neonatal nutritional requirements.

Longitudinal body composition assessment in healthy term-born infants until 2 years of age using ADP and DXA with vacuum cushion

OBJECTIVES

Accelerated gain in fat mass (FM) in early life increases the risk for adult diseases. Longitudinal data on infant body composition are crucial for clinical and research use, but very difficult to obtain due to limited measurement tools and unsuccessful measurements between age 6-24 months. We compared FM% by dual-energy X-ray absorptiometry (DXA), with cushion to reduce movement artifacts, with FM% by air-displacement plethysmography (ADP) and evaluated the reliability of this cushion during DXA by comparing FM% with and without cushion. Subsequently, we constructed sex-specific longitudinal body composition charts from 1-24 months.

METHODS

In 692 healthy, term-born infants (Sophia Pluto Cohort), FM% was measured by ADP from 1-6 months and DXA with cushion from 6-24 months. At 6 months, FM% was measured in triplicate by ADP and DXA with and without cushion(n = 278), later on in smaller numbers.

RESULTS

At 6 months, mean FM% by DXA with cushion was 24.1 and by ADP 25.0, mean difference of 0.9% (Bland-Altman p = 0.321, no proportional bias). Mean FM% by DXA without cushion was 12.5% higher compared to ADP (Bland-Altman p < 0.001). DXA without cushion showed higher mean FM% compared to DXA with cushion (+11.6%, p < 0.001) at 6 months. Longitudinally, FM% increased between 1-6 months and decreased from 6-24 months(both p < 0.001).

CONCLUSIONS

In infants, DXA scan with cushion limits movement artifacts and shows reliable FM%, comparable to ADP. This allowed us to construct longitudinal body composition charts until 24 months. Our study shows that FM% increases from 1-6 months and gradually declines until 24 months.

Birth Size in Neonates with Congenital Adrenal Hyperplasia due to 21-hydroxylase Deficiency

OBJECTIVE

Classic congenital adrenal hyperplasia (CAH) secondary to 21-hydroxylase deficiency is characterized by increased prenatal adrenal androgen secretion. There are a small number of reports in the literature showing higher birth weight and length in CAH newborns.

METHODS

We analyzed birth weight and length data of 116 German newborns (48 boys, 68 girls) with classic CAH who were born during the period from 1990 to 2017. All children have been followed or are currently treated as outpatients in our clinic. All children were born at term. The mothers were healthy and their pregnancies were uneventful. The diagnosis of CAH was confirmed by molecular analyses of the CYP21A2 gene. Birth data were calculated as standard deviation (SD) scores according to German reference values.

RESULTS

Weight and length in male CAH newborns (mean ± SD) (3601±576 g; 52.4±2.85 cm) were significantly higher than in female CAH newborns (3347±442 g; 51.2±2.55 cm), but male-female differences in the CAH cohort were lost when the data were converted into SD scores. The birth sizes of the CAH newborns did not differ from the reference group. The birth sizes also did not differ between the different CAH genotypes. Maternal age, mode of delivery and maternal parity had no influence on birth size.

CONCLUSION

Our data show that prenatal hyperandrogenism does not affect fetal growth.

Maternal obesity and gestational diabetes mellitus affect body composition through infancy: the PONCH study

BACKGROUND

To determine how maternal obesity or gestational diabetes mellitus (GDM) affect infant body size and body composition during the first year of life.

METHODS

Eighty three normal-weight (NW) women, 26 obese (OB) women, and 26 women with GDM were recruited during pregnancy. Infant body composition was determined by air-displacement plethysmography at 1 and 12 weeks, and anthropometric measurements made until 1 year of age.

RESULTS

Girl infants born to OB women and women with GDM had a higher body-fat percentage (BF%) at 1 and 12 weeks of age than girls born to NW women. Girls had higher BF% than boys in OB and GDM groups only. Maternal HbA1c and fasting plasma glucose correlated with girl infant BF% at 1 week of age. Maternal weight at start of pregnancy correlated with birthweight in NW and OB groups, but not the GDM group. OB group infants showed greater BMI increases from 1 week to 1 year than both NW and GDM group infants.

CONCLUSION

Results show that both maternal glycaemia and obesity are determinants of increased early life adiposity, especially in girls, with glycaemic levels being more influential than maternal weight for infants born to women with GDM.

Longitudinal associations of gross motor development, motor milestone achievement and weight-for-length z score in a racially diverse cohort of US infants

OBJECTIVES

To investigate longitudinal associations between gross motor development, motor milestone achievement and weight-for-length z scores in a sample of infants. In a secondary aim, we explored potential bidirectional relationships, as higher weight-for-length z scores may impede motor development, and poor motor development may lead to obesity.

DESIGN

The design was an observational birth cohort.

SETTING

We used data from the Nurture study, a birth cohort of predominately black women and their infants residing in the Southeastern USA.

PARTICIPANTS

666 women enrolled their infants in Nurture. We excluded infants with missing data on exposure, outcome or main covariates, leaving a total analytic sample of 425 infants.

PRIMARY OUTCOME

The outcome was weight-for-length z score, measured when infants were 3, 6, 9 12 months.

RESULTS

Among infants, 64.7% were black, 18.8% were white and 16.9% were other/multiple race. Mean (SD) breastfeeding duration was 17.6 (19.7) weeks. Just over one-third (38.5%) had an annual household income of < $20 000. After adjusting for potential confounders, higher motor development score was associated with lower weight-for-length z score (-0.004; 95% CI -0.001 to -0.007; p=0.01), mainly driven by associations among boys (-0.007; 95% CI -0.014 to -0.001; p=0.03) and not girls (0.001; 95% CI -0.005 to 0.008; p=0.62). Earlier crawling was the only milestone associated with a lower weight-for-length z score at 12 months (-0.328; 95% CI -0.585 to 0.072; p=0.012). However, this association appeared to be driven by male infants only (-0.461; 95% CI -0.825 to -0.096; p=0.01). Weight-for-length z score was unrelated to subsequent motor development score and was thus not bidirectional in our sample.

CONCLUSIONS

Higher motor development score and earlier crawling were associated with lower subsequent weight-for-length z score. However, this was primary true for male infants only. These findings contribute to the growing body of evidence suggesting that delayed motor development may be associated with later obesity.

Accretion of Fat-Free Mass Rather Than Fat Mass in Infancy Is Positively Associated with Linear Growth in Childhood

Background

We have previously shown that fat-free mass (FFM) at birth is associated with height at 2 y of age in Ethiopian children. However, to our knowledge, the relation between changes in body composition during early infancy and later linear growth has not been studied.

Objective

This study examined the associations of early infancy fat mass (FM) and FFM accretion with linear growth from 1 to 5 y of age in Ethiopian children.

Methods

In the infant Anthropometry and Body Composition (iABC) study, a prospective cohort study was carried out in children in Jimma, Ethiopia, followed from birth to 5 y of age. FM and FFM were measured ≤6 times from birth to 6 mo by using air-displacement plethysmography. Linear mixed-effects models were used to identify associations between standardized FM and FFM accretion rates during early infancy and linear growth from 1 to 5 y of age. Standardized accretion rates were obtained by dividing FM and FFM accretion by their respective SD.

Results

FFM accretion from 0 to 6 mo of age was positively associated with length at 1 y (β = 0.64; 95% CI: 0.19, 1.09; P = 0.005) and linear growth from 1 to 5 y (β = 0.63; 95% CI: 0.19, 1.07; P = 0.005). The strongest association with FFM accretion was observed at 1 y. The association with linear growth from 1 to 5 y was mainly engendered by the 1-y association. FM accretion from 0 to 4 mo was positively associated with linear growth from 1 to 5 y (β = 0.45; 95% CI: 0.02, 0.88; P = 0.038) in the fully adjusted model.

Conclusions

In Ethiopian children, FFM accretion was associated with linear growth at 1 y and no clear additional longitudinal effect from 1 to 5 y was observed. FM accretion showed a weak association from 1 to 5 y. This trial was registered at www.controlled-trials.com as ISRCTN46718296.

Cord blood concentrations of leptin, zinc-α2-glycoprotein, and adiponectin, and adiposity gain during the first 3 mo of life

OBJECTIVES

Adipose tissue development starts in intrauterine life and cytokines are involved in this process. Therefore, understanding the role of cytokines in the fat mass gain of infants is crucial to prevent obesity later in life. Furthermore, recent evidence indicates a sex-specific link between cytokines and adipose tissue development. The objective of this study was to assess sex-specific relationships of cord blood concentrations of the cytokines leptin, zinc-α2-glycoprotein (ZAG), and adiponectin with infant adiposity during the first 3 mo of life.

METHODS

This was a prospective cohort study of 104 mother-infant pairs that were selected from a maternity hospital in Sao Paulo, Brazil. Cord blood leptin, ZAG, and adiponectin were determined by enzyme-linked immunosorbent assays. The body composition of the infants was assessed monthly by air displacement plethysmography. A multiple linear regression analysis was conducted with the average fat mass gain from birth to the third month of life as the outcome and cord blood leptin, ZAG, and adiponectin as the variables of interest.

RESULTS

Leptin was inversely associated with fat mass gain in the first 3 mo of life (P = 0.003; adjusted R² = 0.09). There were inverse associations of leptin (P = 0.021), ZAG (P = 0.042), and maternal body mass index (P = 0.04) with fat mass gain in girls (adjusted R² = 0.29) but fat mass gain in boys was positively associated with gestational age (P = 0.01; adjusted R² = 0.15).

CONCLUSIONS

The results of this study suggest that adiposity programming is sex-specific, which highlights the need to investigate the different metabolic mechanisms that are involved in adipogenesis.

Longitudinal fat mass and visceral fat during the first 6 months after birth in healthy infants: support for a critical window for adiposity in early life

INTRODUCTION

Body composition in early life influences the development of obesity during childhood and beyond. It is, therefore, important to adequately determine longitudinal body composition during the first months of life.

PATIENTS AND METHODS

In 203 healthy term infants, we investigated longitudinal body composition, including fat mass percentage (FM%) and fat-free mass (FFM), by air-displacement plethysmography, at 1, 3 and 6 months of age and abdominal visceral fat and abdominal subcutaneous fat, by ultrasound, at 3 and 6 months.

RESULTS

We found a significant increase in FM% between 1 and 3 months but not between 3 and 6 months (p < 0.001, p = 0.098, respectively). Girls had higher FM% than boys at 1 and 6 months (p = 0.05, p < 0.001 respectively) and less FFM than boys at 1, 3 and 6 months (p = 0.02, p = 0.02, p < 0.001, respectively). There was a large variation in FM% at all ages even between infants with similar weight standard deviation scores. Visceral fat and abdominal subcutaneous fat did not change between 3 and 6 months. FM% was highly correlated with abdominal subcutaneous fat but not with visceral fat.

CONCLUSION

Changes in FM% occur mainly in the first 3 months of life, and FM%, visceral and abdominal subcutaneous fat do not change between 3 and 6 months, supporting the concept of a critical window for adiposity development in the first three months of life. In addition, our study provides longitudinal reference data of FM%, FFM, visceral fat and abdominal subcutaneous fat during the first 6 months of life.

Predictors of Infant Body Composition at 5 Months of Age: The Healthy Start Study

OBJECTIVE

To examine associations of demographic, perinatal, and infant feeding characteristics with offspring body composition at approximately 5 months of age.

STUDY DESIGN

We collected data on 640 mother/offspring pairs from early pregnancy through approximately 5 months of age. We assessed offspring body composition with air displacement plethysmography at birth and approximately 5 months of age. Linear regression analyses examined associations between predictors and fat-free mass, fat mass, and percent fat mass (adiposity) at approximately 5 months. Secondary models further adjusted for body composition at birth and rapid infant growth.

RESULTS

Greater prepregnant body mass index and gestational weight gain were associated with greater fat-free mass at approximately 5 months of age, but not after adjustment for fat-free mass at birth. Greater gestational weight gain was also associated with greater fat mass at approximately 5 months of age, independent of fat mass at birth and rapid infant growth, although this did not translate into increased adiposity. Greater percent time of exclusive breastfeeding was associated with lower fat-free mass (-311 g; P < .001), greater fat mass (+224 g; P < .001), and greater adiposity (+3.51%; P < .001). Compared with offspring of non-Hispanic white mothers, offspring of Hispanic mothers had greater adiposity (+2.72%; P < .001) and offspring of non-Hispanic black mothers had lower adiposity (-1.93%; P < .001). Greater adiposity at birth predicted greater adiposity at approximately 5 months of age, independent of infant feeding and rapid infant growth.

CONCLUSIONS

There are clear differences in infant body composition by demographic, perinatal, and infant feeding characteristics, although our data also show that increased adiposity at birth persists through approximately 5 months of age. Our findings warrant further research into implications of differences in infant body composition.

Sex-dependent effects of antenatal glucocorticoids on insulin sensitivity in adult sheep: role of the adipose tissue renin angiotensin system

Exposure to glucocorticoids in utero is associated with changes in organ function and structure in the adult. The aims of this study were to characterize the effects of antenatal exposure to glucocorticoids on glucose handling and the role of adipose tissue. Pregnant sheep received betamethasone (Beta, 0.17 mg/kg) or vehicle 24 h apart at 80 days of gestation and allowed to deliver at term. At 9 mo, male and female offspring were fed at either 100% of nutritional allowance (lean) or ad libitum for 3 mo (obese). At 1 yr, they were chronically instrumented under general anesthesia. Glucose tolerance was evaluated using a bolus of glucose (0.25 g/kg). Adipose tissue was harvested after death to determine mRNA expression levels of angiotensinogen (AGT), angiotensin-converting enzyme (ACE) 1, ACE2, and peroxisome proliferator-activated receptor γ (PPAR-γ). Data are expressed as means ± SE and analyzed by ANOVA. Sex, obesity, and Beta exposure had significant effects on glucose tolerance and mRNA expression. Beta impaired glucose tolerance in lean females but not males. Superimposed obesity worsened the impairment in females and unmasked the defect in males. Beta increased ACE1 mRNA in females and males and AGT in females only (P < 0.05 by three-way ANOVA). Obesity increased AGT in females but had no effect on ACE1 in either males or females. PPAR-γ mRNA exhibited a significant sex (F = 42.8; P < 0.01) and obesity (F = 6.9; P < 0.05) effect and was significantly higher in males (P < 0.01 by three-way ANOVA). We conclude that adipose tissue may play an important role in the sexually dimorphic response to antenatal glucocorticoids.

New body composition reference charts for preterm infants

BACKGROUND

The American Academy of Pediatrics (AAP) has recommended that nutritional management of the preterm infant should aim to achieve body composition that replicates the in utero fetus, but intrauterine body composition reference charts for preterm infants are lacking.

OBJECTIVE

Our objective was to create body composition reference curves for preterm infants that approximate the body composition of the in utero fetus from 30 to 36 wk of gestation.

DESIGN

A total of 223 ethnically diverse infants born at 30 + 0 to 36 + 6 wk of gestation were enrolled. Inclusion and exclusion criteria were specified so that the sample would represent healthy appropriately growing fetuses (e.g., singleton, birth weight appropriate for their gestational age, and medically stable). Cross-sectional reference values were generated for fat mass (FM), fat-free mass (FFM), and percentage body fat (PBF) by gestational age (GA), with the use of air-displacement plethysmography (ADP) and the lambda-mu-sigma method for percentile estimation.

RESULTS

GA-specific percentile values and a percentile and z score calculator for FFM, FM, and PBF are presented. These values aligned closely with ADP centile values published for term infants from 36 to 38 wk of gestation. The medians were also similar to the mean values for the reference fetus derived from chemical analysis previously.

CONCLUSIONS

To our knowledge, these are the first body composition reference charts for total FM and FFM at birth in preterm infants to assist in following AAP guidelines. Future work will test the clinical utility of body composition monitoring for improving nutritional management in this population. This trial was registered at clinicaltrials.gov as NCT02855814.

Abdominal adipose tissue compartments vary with ethnicity in Asian neonates: Growing Up in Singapore Toward Healthy Outcomes birth cohort study

BACKGROUND

A susceptibility to metabolic diseases is associated with abdominal adipose tissue distribution and varies between ethnic groups. The distribution of abdominal adipose tissue at birth may give insights into whether ethnicity-associated variations in metabolic risk originate partly in utero.

OBJECTIVE

We assessed the influence of ethnicity on abdominal adipose tissue compartments in Asian neonates in the Growing Up in Singapore Toward Healthy Outcomes mother-offspring cohort.

DESIGN

MRI was performed at ≤2 wk after birth in 333 neonates born at ≥34 wk of gestation and with birth weights ≥2000 g. Abdominal superficial subcutaneous tissue (sSAT), deep subcutaneous tissue (dSAT), and internal adipose tissue (IAT) compartment volumes (absolute and as a percentage of the total abdominal volume) were quantified.

RESULTS

In multivariate analyses that were controlled for sex, age, and parity, the absolute and percentage of dSAT and the percentage of sSAT (but not absolute sSAT) were greater, whereas absolute IAT (but not the percentage of IAT) was lower, in Indian neonates than in Chinese neonates. Compared with Chinese neonates, Malay neonates had greater percentages of sSAT and dSAT but similar percentages of IAT. Marginal structural model analyses largely confirmed the results on the basis of volume percentages with controlled direct effects of ethnicity on abdominal adipose tissue; dSAT was significantly greater (1.45 mL; 95% CI: 0.49, 2.41 mL, P = 0.003) in non-Chinese (Indian or Malay) neonates than in Chinese neonates. However, ethnic differences in sSAT and IAT were NS [3.06 mL (95% CI:-0.27, 6.39 mL; P = 0.0712) for sSAT and -1.30 mL (95% CI: -2.64, 0.04 mL; P = 0.057) for IAT in non-Chinese compared with Chinese neonates, respectively].

CONCLUSIONS

Indian and Malay neonates have a greater dSAT volume than do Chinese neonates. This finding supports the notion that in utero influences may contribute to higher cardiometabolic risk observed in Indian and Malay persons in our population. If such differences persist in the longitudinal tracking of adipose tissue growth, these differences may contribute to the ethnic disparities in risks of cardiometabolic diseases. This trial was registered at clinicaltrials.gov as NCT01174875.

Human growth and body weight dynamics: an integrative systems model

Quantifying human weight and height dynamics due to growth, aging, and energy balance can inform clinical practice and policy analysis. This paper presents the first mechanism-based model spanning full individual life and capturing changes in body weight, composition and height. Integrating previous empirical and modeling findings and validated against several additional empirical studies, the model replicates key trends in human growth including A) Changes in energy requirements from birth to old ages. B) Short and long-term dynamics of body weight and composition. C) Stunted growth with chronic malnutrition and potential for catch up growth. From obesity policy analysis to treating malnutrition and tracking growth trajectories, the model can address diverse policy questions. For example I find that even without further rise in obesity, the gap between healthy and actual Body Mass Indexes (BMIs) has embedded, for different population groups, a surplus of 14%-24% in energy intake which will be a source of significant inertia in obesity trends. In another analysis, energy deficit percentage needed to reduce BMI by one unit is found to be relatively constant across ages. Accompanying documented and freely available simulation model facilitates diverse applications customized to different sub-populations.

The relationship between bioactive components in breast milk and bone mass in infants

Human breast milk (HBM) contains numerous bioactive components, recently shown to be associated with growth and body composition in breastfed offspring. Reciprocity in adipogenic and osteogenic pathways suggests bone mass may also be influenced by these components. The association between bioactive components found in HBM and bone mineral content (BMC), to our knowledge, is unknown. The purpose of this proof-of-principle study was to evaluate the association between specific bioactive components in HBM in exclusively breastfed infants and skeletal health in the first 6 months of life and examine potential gender differences in these associations. Thirty-five mother-infant dyads were followed from 1 to 6 months. The contents of a single breast expression were used for analyses of bioactive components (insulin, glucose, leptin, interleukin-6 and tumor necrosis factor-α (TNFα), whereas BMC was evaluated by dual-energy X-ray absorptiometry. In the total sample, there was a positive association between TNFα and BMC at 1 (P=0.004) and 6 months (P=0.007). When stratified by sex, females exhibited a positive association between BMC and glucose and an inverse relationship between BMC and TNF-α at 1 month with TNF-α strengthening (P=0.006) at 6 months. In males, at 6 months a positive relationship between BMC and HBM glucose and an inverse relationship with HBM leptin were observed with no associations observed at 1 month. Although preliminary, the associations between bioactive components in HBM highlight the importance HBM has on bone accretion. It is critically important to identify factors in HBM that contribute to optimal bone health.

A search for the most accurate formula for sonographic weight estimation by fetal sex - a retrospective cohort study

OBJECTIVE

The aim of this study was to assess the effect of fetal sex on the accuracy of multiple formulas for sonographic estimation fetal weight (SEFW).

METHODS

The cohort included all singleton live births recorded at a single medical center from January 2004 to September 2011. The accuracy of SEFW was compared between male and female fetuses using 6575 SEFW performed within 3 days prior to delivery. Fetal weight was estimated using 27 models.

RESULTS

The accuracy of different formulas in predicting birth weight of male and female fetuses was found to be significantly different in almost every accuracy index that was compared (P < 0.05). The model by Sabbagha et al. was found to be the most accurate in assessing female fetuses. The most accurate model for male fetuses was a sex-specific formula by Melamed et al. We also found that a combination of the most accurate formula for each sex to one combined sex-specific model increased SEFW accuracy significantly.

CONCLUSION

The accuracy of SEFW is significantly related to fetal sex. The combination of the formulas by Melamed et al. and Sabbagha et al. for male and female fetuses accordingly allowed more accurate SEFW in our research population.

Infant body composition in the PEA POD® era: what have we learned and where do we go from here?

The availability of clinically feasible infant body composition assessment can inform current questions regarding the developmental origins of chronic disease. A strategic approach will facilitate more rapid advancement in knowledge. The objective of this study was to summarize published evidence and ongoing research activity in infant body composition using the PEA POD® infant body composition system. All published studies using the PEA POD® were identified and grouped according to study population and question. All centers with PEA POD® units were invited to participate in an online survey regarding past, current and future PEA POD® use, and results were analyzed using descriptive statistics. The resulting information was used to identify gaps or limitations in existing knowledge, thus highlighting potential research priorities. Twenty-seven published articles were identified and grouped into six research themes. Although the number of infants studied is significant in some areas, interpretation of data is limited by methodological differences. Survey responses were received from 16 of ∼60 centers. Research themes echoed those identified from the published literature. Controlling for or reporting potential confounding variables is essential for understanding infant body composition data. Measurement of health outcome variables would be helpful in identifying associations.

Body composition assessment in infancy and early childhood: comparison of anthropometry with dual-energy X-ray absorptiometry in low-income group children from India

BACKGROUND/OBJECTIVE

Anthropometry is a simple, inexpensive method of body composition assessment, but its validity has not been examined adequately in young children. The study therefore compared the body composition estimates using anthropometry with those using dual-energy X-ray absorptiometry (DXA) in infants and young children.

METHODS

Body composition estimates using anthropometry and DXA were assessed and compared at 6, 12 and 18 months in a cohort of 137 infants enrolled at birth.

RESULTS

Fat mass (FM) and body fat percent (%BF) estimates by anthropometry were lower than those using DXA. Mean differences (DXA-skinfold thickness) in FM, fat free mass (FFM) and %BF were highest at 6 months (350 g, -226 g and 4%, respectively); the differences reduced with increase in age and were lowest at 18 months (46 g, 56 g and 0%, respectively). Bland-Altman analyses showed good agreement between the FM, FFM and %BF estimates by the two methods only at 18 months. Accretion of FM and FFM during follow-up, estimated by the two methods, was significantly different, with agreement between the methods seen only for increment in FFM from 6 to 12 months.

CONCLUSIONS

Substantial differences were found in the body composition estimates by anthropometry compared with DXA and also in the longitudinally assessed tissue accretion patterns by the two methods. As the body composition patterns may be influenced by the method used for body composition assessment, results of studies assessing body composition by anthropometry during infancy should be interpreted with caution.

Characterization of the infant BMI peak: sex differences, birth year cohort effects, association with concurrent adiposity, and heritability

OBJECTIVES

To characterize an early trait in the BMI-for-age curve, the infant BMI peak.

METHODS

BMI-for-age curves were produced for 747 non-Hispanic, white Fels Longitudinal Study participants, from which individual age (AgePeak ) and BMI (BMIPeak ) at maximum infant BMI were estimated. Multivariable general linear regression was used to examine the effects of sex and birth year cohort (1929-1950, 1951-1970, and 1971-2010) on AgePeak and BMIPeak , with associations between BMIPeak and concurrent sum of four skinfold thicknesses assessed in a subsample (N = 155). Heritability (h(2) ) of AgePeak and BMIPeak was estimated using maximum-likelihood variance components analysis.

RESULTS

AgePeak occurred at 9 months of age in both sexes, but BMIPeak was 0.4 kg/m(2) higher for boys than for girls (P-value < 0.001). Infants born between 1971 and 2010 experienced a 1.5 month earlier AgePeak and a 0.35 kg/m(2) lower BMIPeak than infants born between 1929 and 1950 (P-values < 0.001). Skinfold thickness explained 37% of the variance in BMIPeak in boys and 20% of the variance in girls (p-values < 0.001). AgePeak and BMIPeak were significantly heritable (h(2) = 0.54 and 0.75, respectively).

CONCLUSIONS

Both AgePeak and BMIPeak decreased over successive birth year cohorts in the Fels Longitudinal Study. Despite a positive association of BMIPeak with concurrent adiposity, AgePeak appears to occur later than does the well-documented peak in infant fat mass and BMIPeak does not capture known sex differences in infant adiposity. Strong heritability of these infant BMI traits suggests investigation of genetic control, and validation of their relationship to body composition is greatly needed.

Dynamics of human milk nutrient composition of women from Singapore with a special focus on lipids

BACKGROUND

A recent report suggested that human milk (HM) composition not only changes with lactation stages but also vary according to gender of the offspring. In spite of available literature, the dynamic changes of HM composition still remain to be completely explored and characterized. Progress in analytical technologies together with quantitative sampling of HM allows for a better quantification of HM nutrients and thereby providing a deeper understanding of the dynamics of HM secretion.

OBJECTIVE

To characterize and quantify HM nutrients based on appropriate for analyses sampling procedures and advanced analytical methodologies.

CLINICAL STUDY DESIGN

We conducted an observatory, single center, longitudinal trial with HM collection at 30, 60, and 120 days postpartum from 50 mothers (singleton-deliveries of 25 male and 25 female infants). HM samples were analyzed for lipid, lactose, energy density, fatty acids, phospholipids, and gangliosides. Longitudinal analyses of the datasets have been carried out using linear mixed models.

RESULTS

HM for male infants compared to females at 120 days, were higher for energy content and lipids by 24 and 39%, respectively. Similarly, other bioactive lipids such as linoleic acid, phospholipids and gangliosides were also significantly different based on the gender of the infant. Significant stage-based differences were observed for total lipids, energy density, phospholipids, and gangliosides. Such difference in HM composition may stem from different energy needs to cope up for individual growth and development.

CONCLUSION

Collectively, the current observations affirm that HM secretion, especially the lipid composition, is a very dynamic and personalized biological process.

The relationship of newborn adiposity to fetal growth outcome based on birth weight or the modified neonatal growth assessment score

OBJECTIVES

(1) Develop reference ranges of neonatal adiposity using air displacement plethysmography. (2) Use new reference ranges for neonatal adiposity to compare two different methods of evaluating neonatal nutritional status.

METHODS

Three hundred and twenty-four normal neonates (35-41 weeks post-menstrual age) had body fat (%BF) and total fat mass (FM, g) measured using air displacement plethysmography shortly after delivery. Results were stratified for 92 of these neonates with corresponding fetal biometry using two methods for classifying nutritional status: (1) population-based weight percentiles; and (2) a modified neonatal growth assessment score (m(3)NGAS(51)).

RESULTS

At the 50th percentile, %BF varied from 7.7% (35 weeks) to 11.8% (41 weeks), while the corresponding 50th percentiles for total FM were 186-436 g. Among the subset of 92 neonates, no significant differences in adiposity were found between small for gestational age (SGA), appropriate for gestational age (AGA), and large for gestational age (LGA) groups using population-based weight standards. Classification of the same neonates using m(3)NGAS(51) showed significant differences in mean %BF between corresponding groups.

CONCLUSIONS

Population-based weight criteria for neonatal nutritional status can lead to misclassifications on the basis of adiposity. A neonatal growth assessment score, that considers the growth potential of several anatomic parameters, appears to more effectively classify under- and over-nourished newborns.

Does use of a sex-specific model improve the accuracy of sonographic weight estimation?

OBJECTIVE

To determine whether the use of a sex-specific sonographic model improves the accuracy of fetal weight estimation.

METHODS

New regression models (sex-independent and sex-specific) were developed, based on 1708 sonographic weight estimations performed within 3 days prior to delivery. The accuracy of these models was compared to that of several published models including two of the original Hadlock models (which incorporate the biometric indices abdominal circumference (AC), biparietal diameter (BPD), femur diaphysis length (FL) and head circumference (HC) as follows: AC-FL-BPD and AC-FL-HC, designated here as Hadlock I and Hadlock II, respectively), modified versions of the Hadlock I and II models for which coefficients were adjusted to our local cohort, sex-specific versions of the Hadlock I and II models and Schild's model (a previously published sex-specific model).

RESULTS

The unadjusted models of Hadlock and Schild were associated with the highest systematic error (1.6-4.9%; P < 0.001) which was significantly higher for females (2.3-4.9%) compared to males (1.6-2.0%; P < 0.001). Adjustment of model coefficients to the local population decreased the systematic error (-1.4% to 1.5%) and resulted in a systematic error that was of similar magnitude (P = 0.3) but opposite in direction for male and female fetuses. The sex-specific models (adjusted or newly developed) were associated with the lowest systematic error (-0.4 to 0.5%) and were the only models for which the systematic error was similar for male and female fetuses. There were no differences in the systematic error between adjusted sex-specific versions of the Hadlock I and II models and the newly developed sex-specific models (0.0% to 0.4% vs. - 0.4% to 0.5%; P = 0.4). The random error was similar for all models and, for most of the models, was unrelated to fetal sex.

CONCLUSIONS

The use of sex-specific models appears to improve the accuracy of fetal weight estimation, principally because the optimal set of model coefficients differs for male and female fetuses. The improved accuracy is mainly the result of a decrease in systematic error, as the random error was not affected by the use of such sex-specific models.

Effect of breastfeeding compared with formula feeding on infant body composition: a systematic review and meta-analysis

BACKGROUND

Early-life nutrition may influence later body composition. The effect of breastfeeding and formula feeding on infant body composition is uncertain.

OBJECTIVE

We conducted a systematic review and meta-analysis of studies that examined body composition in healthy, term infants in relation to breastfeeding or formula feeding.

DESIGN

PubMed was searched for human studies that reported the outcomes fat-free mass, fat mass, or the percentage of fat mass in breastfed and formula-fed infants. Bibliographies were hand searched, and authors were contacted for additional data. The quality of studies was assessed. Differences in outcomes between feeding groups were compared at prespecified ages by using fixed-effects analyses except when heterogeneity indicated the use of random-effects analyses.

RESULTS

We identified 15 studies for inclusion in the systematic review and 11 studies for inclusion in the meta-analysis. In formula-fed infants, fat-free mass was higher at 3-4 mo [mean difference (95% CI): 0.13 kg (0.03, 0.23 kg)], 8-9 mo [0.29 kg (0.09, 0.49 kg)], and 12 mo [0.30 kg (0.13, 0.48 kg)], and fat mass was lower at 3-4 mo [-0.09 kg (-0.18, -0.01 kg)] and 6 mo [-0.18 kg (-0.34, -0.01 kg)] than in breastfed infants. Conversely, at 12 mo, fat mass was higher in formula-fed infants [0.29 kg (-0.03, 0.61 kg)] than in breastfed infants.

CONCLUSION

Compared with breastfeeding, formula feeding is associated with altered body composition in infancy.

Fat and fat-free mass at birth: air displacement plethysmography measurements on 350 Ethiopian newborns

LBW increases the risk of a number of noncommunicable diseases in adulthood. However, birth weight (BW) cannot describe variability in infant body composition (BC). Variability in fat mass (FM) and fat-free mass (FFM) at birth may be particularly important in low-income countries because they undergo nutritional transition. There is a need for data on birth BC and its predictors from low-income countries in transition. We assessed absolute FM and FFM at birth and examined the role of gender, parity, GA, and LBW as predictors of birth BC. FM and FFM were assessed within 48 h of birth on 350 Ethiopian newborns using air displacement plethysmography (ADP). Female gender and being an infant of primi- or secundiparous mothers predicted lower BW and lower birth FFM but not FM, compared with male gender and infants of multiparous mothers, respectively. There was a positive linear relationship between BW and relative amount of FM for boys and girls. This study presents reference data on birth FM and FFM from a low-income setting and provides background for further longitudinal mapping of the relationship between fetal BC, childhood growth, and adult disease.

Gender- and gestational age-specific body fat percentage at birth

BACKGROUND

There is increasing evidence that in utero growth has both immediate and far-reaching influence on health. Birth weight and length are used as surrogate measures of in utero growth. However, these measures poorly reflect neonatal adiposity. Air-displacement plethysmography has been validated for the measurement of body fat in the neonatal population.

OBJECTIVE

The goal of this study was to show the normal reference values of percentage body fat (%BF) in infants during the first 4 days of life.

METHODS

As part of a large population-based birth cohort study, fat mass, fat-free mass, and %BF were measured within the first 4 days of life using air-displacement plethsymography. Infants were grouped into gestational age and gender categories.

RESULTS

Of the 786 enrolled infants, fat mass, fat-free mass, and %BF were measured in 743 (94.5%) infants within the first 4 days of life. %BF increased significantly with gestational age. Mean (SD) %BF at 36 to 37⁶/⁷ weeks' gestation was 8.9% (3.5%); at 38 to 39 weeks' gestation, 10.3% (4%); and at 40 to 41⁶/⁷ weeks' gestation, 11.2% (4.3%) (P < .001). Female infants had significantly increased mean (SD) %BF at 38 to 39⁶/⁷ (11.1% [3.9%] vs 9.8% [3.9%]; P = .012) and at 40 to 41⁶/⁷ (12.5% [4.4%] vs 10% [3.9%]; P < .001) weeks' gestation compared with male infants. Gender- and gestational age-specific centiles were calculated, and a normative table was generated for reference.

CONCLUSION

%BF at birth is influenced by gestational age and gender. We generated accurate %BF centiles from a large population-based cohort.

Accuracy of sonographic weight estimation as a function of fetal sex

OBJECTIVES

To determine whether the accuracy of sonographic fetal weight estimation is related to fetal sex.

METHODS

The accuracy of sonographic fetal weight estimation was compared between male and female fetuses using 3672 sonographic weight estimations performed within 3 days prior to delivery. Fetal weight was estimated using eight regression models that are based on different combinations of the following biometric parameters: abdominal circumference (AC), femur diaphysis length (FL), biparietal diameter (BPD) and head circumference (HC).

RESULTS

In seven out of the eight models tested, the presence of a male fetus was associated with a significantly lower systematic error compared with a female fetus (-0.2 to 2.1% vs. 1.3 to 6%, P<0.001). On multivariate analysis, fetal sex was independently associated with sonographic accuracy so that the likelihood of a weight estimation within 10% of birth weight was 30% higher for male fetuses compared with female fetuses. The biometric parameters that contributed most to these sex-related differences were FL and AC, while models that included HC were associated with the lowest differences in the systematic error between male fetuses and female fetuses. For most models, the random error and correlation between estimated weight and birth weight were not affected by fetal sex (8.1-12.8% vs. 8.2-13.6%, and 0.856-0.944 vs. 0.842-0.944, respectively).

CONCLUSION

Sonographic estimation of fetal weight is more accurate for male fetuses than for female fetuses. The use of sex-specific models may improve the accuracy of fetal weight estimation for female fetuses.

Normal sex differences in prenatal growth and abnormal prenatal growth retardation associated with 46,XY disorders of sex development are absent in newborns with congenital adrenal hyperplasia due to 21-hydroxylase deficiency

Background

Congenital adrenal hyperplasia due to 21-hydroxylase deficiency is the most common presentation of a disorder of sex development (DSD) in genetic females. A report of prenatal growth retardation in cases of 46,XY DSD, coupled with observations of below-optimal final height in both males and females with congenital adrenal hyperplasia due to 21-hydroxylase deficiency, prompted us to investigate prenatal growth in the latter group. Additionally, because girls with congenital adrenal hyperplasia are exposed to increased levels of androgens in the absence of a male sex-chromosome complement, the presence or absence of typical sex differences in growth of newborns would support or refute a hormonal explanation for these differences.

Methods

In total, 105 newborns with congenital adrenal hyperplasia were identified in our database. Gestational age (weeks), birth weight (kg), birth length (cm) and parental heights (cm) were obtained. Mid-parental height was considered in the analyses.

Results

Mean birth weight percentile for congenital adrenal hyperplasia was 49.26%, indicating no evidence of a difference in birth weight from the expected standard population median of 50th percentile (P > 0.05). The expected sex difference in favor of heavier males was not seen (P > 0.05). Of the 105 subjects, 44 (27%; 34 females, 10 males) had birth length and gestational age recorded in their medical chart. Mean birth length for this subgroup was 50.90 cm (63rd percentile), which differed from the expected standard population median of 50th percentile (P = 0.0082). The expected sex difference in favor of longer males was also not seen (P > 0.05).

Conclusion

The prenatal growth retardation patterns reported in cases of 46,XY disorders of sex development do not generalize to people with congenital adrenal hyperplasia due to 21-hydroxylase deficiency. Sex differences in body weight and length typically seen in young infants were not seen in the subjects who participated in this study. We speculate that these differences were ameliorated in this study because of increased levels of prenatal androgens experienced by the females infants.

Fat-free mass hydration in newborns: assessment and implications for body composition studies

AIM

Equipment (Pea Pod) offering new possibilities to assess infant body composition has recently become available and has already been used in several studies. In the Pea Pod, body density is converted to body composition using one of two models ('Fomon' or 'Butte') with different water content in fat-free mass (hydration factor, HF). In healthy full-term infants, we assessed HF and its biological variability in 12 newborns and calculated body composition using the two models at 1 and 12 weeks in 108 infants. Body weight and volume were assessed in Pea Pod, and body water was assessed using isotope dilution.

RESULTS

Hydration factor was 80.9% with low biological variability (0.8% of average HF). Body fat (%) was significantly lower at 1 and 12 weeks when calculated using the 'Butte' model than when using the 'Fomon' model. The difference was more pronounced at one than at 12 weeks.

CONCLUSION

  Our HF value agrees with that in the 'Fomon' model, its low biological variability can be reconciled with the statement that Pea Pod is accurate in newborns and 'Fomon' is the best available model for studies in Pea Pod.

Body composition in full-term healthy infants measured with air displacement plethysmography at 1 and 12 weeks of age

AIM

To use Pea Pod, a device based on air displacement plethysmography, to study body composition of healthy, full-term infants born to well-nourished women with a western life-style.

METHODS

Body composition was assessed in 53 girls and 55 boys at 1 week (before 10 days of age) and at 12 weeks (between 77 and 91 days of age).

RESULTS

At 1 week girls contained 13.4 +/- 3.7% body fat and boys 12.5 +/- 4.0%. At 12 weeks, these figures were 26.3 +/- 4.2% (girls) and 26.4 +/- 5.1% (boys). Body fat (%) did not differ significantly between the genders. Body fat (%) at the two measurements was not correlated. At 1 week, the weight (r = 0.20, p = 0.044) and BMI (r = 0.26, p = 0.007) of the infants, but not their body fat (g, %) or fat free mass (g), correlated with BMI before pregnancy in their mothers.

CONCLUSIONS

Pea Pod has potential for use in studies investigating the effect of external (i.e. nutritional status) and internal (i.e. age, gender, gestational age at birth) factors on infant body composition. This may be of value when studying relationships between the nutritional situation during early life and adult health.