Association between birthweight and body mass index at 3 years of age

INTERGROWTH-21st versus a customized method for the prediction of neonatal nutritional status in hypertensive disorders of pregnancy

Background

Hypertensive disorders of pregnancy (HDP) generate complications and are one of the principal causes of maternal, foetal, and neonatal mortality worldwide. It has been observed that in pregnancies with HDP, the incidence of foetuses small for their gestational age (SGA) is twice as high as that in noncomplicated pregnancies. In women with HDP, the identification of foetuses (SGA) is substantially important, as management and follow-up are determined by this information.

Objective

The objective of this study was to evaluate whether the INTERGROWTH-21st method or customized birthweight references better identify newborns with an abnormal nutritional status resulting from HDP.

Method

A comparative analysis study was designed with two diagnostic methods for the prediction of neonatal nutritional status in pregnancies with HDP. The performance of both methods in identifying neonatal malnutrition (defined by a neonatal body mass index < 10^th centile or a ponderal index < 10^th centile) was assessed by calculating sensitivity, specificity, positive predictive value, negative predictive value, diagnostic odds ratio, Youden’s index and probability ratios.

Results

The study included 226 pregnant women diagnosed with HDP. The customized method identified 45 foetuses as small for gestational age (19.9%), while the INTERGROWTH-21st method identified 27 newborns with SGA (11.9%). The difference between proportions was statistically significant (p < 0.01). Using body mass index (< 10^th centile) as a measure of nutritional status, newborns identified as SGA by the customized method showed a higher risk of malnutrition than those identified as SGA by INTERGROWTH-21st (RR: 4.87 (95% CI: 1.86–12.77) vs. 3.75 (95% CI: 1.49–9.43)) (DOR: 5.56 (95% CI: 1.82–16.98) vs. 4.84 (95% CI: 1.51–15.54)) Even when using Ponderal index (< 10^th centile), newborns identified as SGA by the customized method showed a higher risk of malnutrition than those identified as SGA by INTERGROWTH-21st (RR 2.37 (95% CI: 1.11–5.05) vs. 1.68 (95% CI: 0.70–4.03))(DOR 2.62 (95% CI: 1.00–6.87) vs. 1.90 (95% CI: 0.61–5.92)).

Conclusion

In pregnant women with HDP, the predictive ability of the customized foetal growth curves to identify neonatal malnutrition appears to surpass that of INTERGROWTH-21st.

Association between fetal macrosomia and risk of obesity in children under 3 years in Western China: a cohort study

BACKGROUND

Fetal macrosomia, defined as birth weight equal or over 4000 g, is a major concern for both neonatal and maternal health. A rapid increasing trend in fetal macrosomia is observed in different regions of China. We aimed to examine the association between fetal macrosomia and risk of childhood obesity in Western China.

METHODS

All macrosomic live singletons (≥ 4000 g), and a random sample of singletons with normal birth weight (2500-3999 g) born in four districts of Chengdu, Western China, in 2011 were included in the cohort study. Maternal demographics, obstetric factors, labor and delivery summary at baseline were extracted from the Chengdu Maternal and Child Health Management System. Anthropometric measurements before 3 years and infant feeding information at around 6 months were also collected. Childhood obesity under 3 years was primarily defined as a weight-for-length/height z score ≥ 1.645 using the WHO growth reference. Secondary definitions were based on weight-for-age and body mass index (BMI)-for-age over the same cut-offs.

RESULTS

A total of 1767 infants were included in the analyses, of whom 714 were macrosomic. After controlling for maternal age, parity, gestational age and anemia at the first antenatal visit, pre-pregnancy BMI, gestational weight gain, gestational age at birth, baby age and sex, and breastfeeding practices at 6 months, the risk of childhood obesity defined according to weight-for-length/height among macrosomic babies was 1.90 (95% confidence interval 1.04-3.49) times that of babies with normal birth weight. The risk of childhood obesity for macrosomic babies was 3.74 (1.96-7.14) and 1.64 (0.89-3.00) times higher based on weight-for-age and BMI-for-age, respectively.

CONCLUSION

Fetal macrosomia is associated with increased risk of obesity in children under 3 years in Western China.

Growth in exclusively breastfed infants

OBJECTIVE

To address the growth of full-term children in the first 6 months of life in exclusive breastfeeding.

SOURCE OF DATA

A non-systematic review was carried out by searching the MEDLINE/PubMed, Web of Science, and Cochrane Library databases and the World Health Organization website for articles and documents on the growth of exclusively breastfed infants and their monitoring. Those documents considered to be the most relevant by the author were selected.

DATA SYNTHESIS

Exclusively breastfeed infants show differentiated growth when compared to formula-fed infants. Weight loss in the first four days of life is due more to loss of fat mass rather than lean mass, including body water, and is usually lower in exclusively breastfed infants. In turn, the time for recovery of the birth weight may be longer in these infants. Formula-fed infants gain weight and increase their BMI more rapidly in the first three to six months of life than infants in exclusive or predominant breastfeeding due to a progressive increase in lean mass. The World Health Organization growth curves, which use the growth pattern of breastfed children as their standard, are used to monitor growth.

CONCLUSIONS

Exclusively breastfed infants have differentiated growth when compared with formula-fed infants. This should be considered when monitoring the infant's growth. It should be emphasized that the growth pattern currently used as reference is that of the exclusively breastfed infant.

Rapid growth in early childhood associated with young adult overweight and obesity--evidence from a community based cohort study

BACKGROUND

Rapid weight gain in early life may increase the risk of overweight and obesity in adulthood. We investigated the association between the rate of growth during early childhood and the development of overweight and obesity in young adults.

METHODS

We used a prospective cohort study of 2077 young adults who were born between 1981 and 1984 in Brisbane, Australia and had anthropometry measurements available at birth, 6 months, 5 years, 14 years and 21 years of age. The associations of rate of early growth with body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) and their categories at 21 years were studied using multivariate analysis.

RESULTS

We found that rapid weight gain [> + 0.67 standard deviation score (SDS)] in the first 5 years of life was associated with young adults' overweight status (BMI: adjusted OR = 2.35, 95% CI, 1.82-3.03; WC: adjusted OR = 2.20, 95% CI, 1.65-2.95). We also observed that slow weight gain in the first 5 years of age (< -0.67 SDS) was inversely associated with overweight (BMI: OR = 0.62, 95% CI, 0.45-0.84). Such associations were not found with WHR. Rapid weight gain in the first 6 months of life increased the risk of overweight as defined by BMI (adjusted OR = 1.13, 95% CI, 0.86-1.49) and WC (adjusted OR = 1.24, 95% CI, 0.92-1.67), but these associations were not statistically significant.

CONCLUSION

Rapid weight gain in the first 5 years of life in children increased their risk of a higher BMI and WC in young adulthood, in contrast slow weight gain was inversely associated with weight status at 21 years.

Fetal thigh and upper-arm volumes by three-dimensional ultrasound to predict low postnatal body mass index

OBJECTIVE

To assess the usefulness of estimating fetal upper arm and thigh volumes as predictors of low postnatal body mass index (BMI) using three-dimensional ultrasonography (3DUS) with extended imaging virtual organ computer-aided analysis (XI VOCAL).

METHODS

This prospective cross-sectional study analyzed 300 singleton pregnancies between 33 and 41 weeks of gestation. The Hadlock 4 formula was used to estimate fetal weight. The XI VOCAL 10 planes method was used to assess fetal upper arm and thigh volumes. After delivery, the newborns' BMI was evaluated and considered low (≤10th percentile) or normal (>10th percentile). We determined receiver operating characteristics (ROC) curves and respective areas under the curves for the percentiles of fetal weight and fetal thigh and upper arm volumes.

RESULTS

Of the 300 newborns, BMI was ≤10th percentile for 21 and >10th percentile for 279 newborns. The area under the ROC curve for fetal weight, obtained using the Hadlock formula, and fetal upper arm and thigh volumes, obtained by 3DUS, were 0.801, 0.930 and 0.924, respectively. We determined the sensitivity and specificity of the three parameters for predicting low postnatal BMI and found values of 85.70% and 65.60%, respectively, for fetal weight, 90.48% and 88.17%, respectively, for fetal thigh volume, and 76.19% and 92.47%, respectively, for fetal upper arm volume.

CONCLUSION

Fetal upper arm and thigh volumes estimated using 3DUS with XI VOCAL were effective predictors of low postnatal BMI.

Early infantile growth and cardiovascular risks in adolescent Japanese women

Objective: Early life events connected with the risk of later disease can occur not only in utero, but also in infancy. In study of the developmental origins of health and disease, the relationship between infantile growth patterns and adolescent body mass index and blood pressure is one of the most important issues to verify.

Materials and Methods: We analyzed the correlation of current body mass index and systolic blood pressure of 168 female college students with their growth patterns in utero and in infancy.

Results: Body mass index and systolic blood pressure in adolescence showed positive correlations with changes in weight-for-age z scores between 1 and 18 months but not with those between 18 and 36 months. Stepwise multiple regression analysis showed that both change in weight-for-age z scores from 1 to 18 months and body mass index at 1 month were significantly and independently associated with systolic blood pressure in adolescence. Body mass index at 36 months was positively correlated with body mass index in adolescence, while body mass index at birth was negatively correlated with body mass index in adolescence.

Conclusion: Our findings shows that restricted growth in utero and accelerated weight gain in early infancy are associated with the cardiovascular risk factors of high systolic blood pressure and high body mass index in adolescence. In Japan, an increasing proportion of low birth weight infants and accelerated catch-up growth after birth have been observed in recent decades. This might be an alarming harbinger of an increase in diseases related to the developmental origins of health and disease in Japan.

Biological determinants linking infant weight gain and child obesity: current knowledge and future directions

Childhood obesity rates have reached epidemic proportions. Excessive weight gain in infancy is associated with persistence of elevated weight status and later obesity. In this review, we make the case that weight gain in the first 6 mo is especially predictive of later obesity risk due to the metabolic programming that can occur early postpartum. The current state of knowledge regarding the biological determinants of excess infant weight gain is reviewed, with particular focus on infant feeding choice. Potential mechanisms by which different feeding approaches may program the metabolic profile of the infant, causing the link between early weight gain and later obesity are proposed. These mechanisms are likely highly complex and involve synergistic interactions between endocrine effects and factors that alter the inflammatory and oxidative stress status of the infant. Gaps in current knowledge are highlighted. These include a lack of data describing 1) what type of infant body fat distribution may impart risk and 2) how maternal metabolic dysfunction (obesity and/or diabetes) may affect milk composition and exert downstream effects on infant metabolism. Improved understanding and management of these early postnatal determinants of childhood obesity may have great impact on reducing its prevalence.

Bases biológicas e evidências epidemiológicas da contribuição do crescimento fetal e pós-natal na composição corporal: uma revisão

OBJETIVOS: apresentar as bases biológicas e evidências epidemiológicas do crescimento fetal e pós-natal relacionadas ao tamanho e composição corporal. MÉTODOS: a busca de artigos publicados nos últimos 15 anos foi realizada nas bases de dados Lilacs, SciELO, Medline através dos descritores: crescimento, restrição do crescimento fetal, baixo peso ao nascer, aceleração compensatória do crescimento, composição corporal, índice de massa corporal e hormônios. Os estudos foram selecionados de acordo com a pertinência às evidências a serem analisadas. RESULTADOS: os artigos apontam para a influência da restrição do crescimento intraútero na supressão da termogênese e regulação hormonal, que por sua vez interferem no ganho de peso após o nascimento, e explicam como ambos os processos, restrição do crescimento fetal e rápido ganho de peso pós-natal, influenciam as medidas corporais em fases posteriores da vida, com consequências que poderão afetar gerações. CONCLUSÕES: o crescimento fetal influencia o padrão de crescimento pós-natal devido a diversos fatores relacionados à regulação hormonal, porém existe ainda uma lacuna sobre a contribuição da somação entre crescimento fetal e pós-natal no tamanho e composição corporal em fases posteriores da vida.

Parental age and child growth and development: child health check-up data

BACKGROUND

The aim of the present study was to determine whether parental age has any influence on child health.

METHODS

Well-baby check-up data at 1 month and at 12 months of age were used. The trends of parental age in association with growth measurements, incidence of physical and developmental abnormalities, occurrence of low birthweight, and maternal history of spontaneous abortion were analyzed.

RESULTS

Associations between increasing paternal age and incidence of psychomotor developmental delay at 12 months, increasing paternal and maternal age and increasing birthweight, and increasing parental age and higher incidence of history of spontaneous abortion were found. The incidence of low-birthweight infants was significantly decreased with increasing paternal age.

CONCLUSIONS

Not only increasing maternal age but also increasing paternal age have influences on child development and growth in the general population.

Rapid weight gain in early infancy is associated with adult body fat percentage in young women

OBJECTIVES

Although rapid childhood weight gain has been suggested to be a risk factor for lifetime obesity and other chronic diseases, few studies have been conducted in Asian populations. The aim of this study was, therefore, to ascertain whether rapid childhood weight gain is associated with indices of obesity in adulthood and, if so, which period in early development provides the greatest predictive value of future obesity in young Japanese women.

METHODS

A total of 86 female university students aged 18-21 years old participated in this study. Current height, weight, body fat percentage (BFP) as evaluated by bioelectrical impedance analysis, and BMI were measured. Body weight at birth, 3 and 6 months, and 1.5 and 3 years of age was obtained from the maternity record book (Boshi-techo), and body weight at 6 years was obtained from school health records. We assessed infant weight gain by the weight change Z-score.

RESULTS

Current BFP was found to be significantly correlated with weight change between 0 and 3 months (r = 0.26, P = 0.034) and between 3 and 6 months of age (r = -0.28, P = 0.031). However, none of the physical activity indices correlated with BMI and BFP.

CONCLUSIONS

Rapid weight gain in early infancy positively associates with BFP in young Japanese women.

High birth weight and overweight or obesity among Chinese children 3-6 years old

OBJECTIVE

To investigate the association between different levels of birth weight and the risk of overweight and obesity in children aged 3-6 years.

METHODS

A retrospective longitudinal study of 15,852 children aged 3-6 years in Tianjin, China. Body weight and height, and other factors (age, gestational age, past and current health status, father's and mother's education, occupation and health status, family income, and sex) were obtained using standardized methods.

RESULTS

After adjustment for the above other factors, Chinese children who were born with a birth weight below 2500 g are less likely to become overweight or obese (body mass index more than the 85th percentiles for age and gender specific distribution using the World Health Organization growth reference) during childhood (odd ratio [OR] 0.84, 95% confidence interval [CI] 0.47-1.52) when compared to the reference group (2500-2999 g). However, the odds ratios of becoming overweight or obese during childhood increase significantly when birth weights are 3000-3499 g (OR 1.58, 95% CI 1.33-1.88), 3500-3999 g (OR 2.09, 95% CI 1.76-2.49), and more than 4000 g (OR 3.14, 95% CI 2.60-3.79).

CONCLUSIONS

High levels of birth weight, defined as birth weight >3000 g, were a stronger predictor for overweight and obesity among the Chinese children aged 3-6 years.

Taller stature after postnatal rapid weight gain in early infancy predicts overweight status at age 3

AIM

To evaluate whether postnatal rapid weight gain in early infancy is associated with subsequent tall stature and being overweight at age 3, and taller stature after postnatal rapid weight gain predicts overweight status at age 3.

METHODS

Data from a retrospective cohort study (time period 2003-2004, total number = 1353 subjects in Kumamoto, Japan) were used. The rate of weight gain during the first 3-4 months was calculated as 100 g/month, and postnatal rapid and slow growth were calculated by using weight standard deviation (SD). Overweight status at 3 years of age was determined according to the definition of the International Obesity Task Force.

RESULTS

In total, 4.7% of subjects were overweight at age 3. Postnatal rapid weight gain, associated with height increases until age 3 (p < 0.0001), and the rate of weight gain were significant risk factors for being overweight in children at age 3. Taller heights at 6-9 months and 17-20 months of age following postnatal rapid weight gain were associated with overweight status at age 3 (p < 0.05).

CONCLUSION

Taller stature following postnatal rapid weight gain in early infancy predicts overweight status at age 3; additionally, rapid infancy weight gain contributes to the acceleration of statural growth in overweight children.

Avaliação nutricional do recém-nascido: limitações dos métodos atuais e novas perspectivas

OBJETIVO: Revisar a literatura sobre as abordagens na avaliação nutricional do recém-nascido. FONTES DE DADOS: Levantamento das publicações sobre avaliação nutricional de recém-nascidos indexadas no Medline, SciELO e Lilacs nos últimos dez anos, utilizando os descritores "antropometria" e "avaliação nutricional". SÍNTESE DOS DADOS: A avaliação nutricional do recém-nascido é importante tanto para classificação e diagnóstico de alterações do crescimento intra-uterino, quanto para posterior acompanhamento nutricional e de crescimento. Esta avaliação compreende parâmetros antropométricos, bioquímicos e de composição corpórea. Devido à limitação de métodos laboratoriais e de composição corpórea, a avaliação nutricional do recém-nascido continua sendo baseada em parâmetros antropométricos, como peso, comprimento, perímetros cefálico e braquial e dobras cutâneas. Além dos parâmetros antropométricos, as relações antropométricas são úteis para descrever proporcionalidades corpóreas. Dentre tais relações, destacam-se: razão entre perímetros braquial e cefálico e índice ponderal. O índice de massa corpórea (IMC), bastante utilizado em crianças e adultos como indicador de proporcionalidade do crescimento, não conta com valores de referência para recém-nascidos. CONCLUSÕES: Curvas de IMC para recém-nascidos representariam um complemento na avaliação nutricional neonatal e poderiam proporcionar melhor compreensão do padrão de crescimento intra-uterino e suas variações.

Maternal smoking during pregnancy and child overweight: systematic review and meta-analysis

OBJECTIVE

Perform a systematic review of studies reporting on the association between maternal prenatal cigarette smoking and child overweight.

DESIGN

Meta-analysis of observational studies.

DATA SOURCES

Medline search and review of reference lists among studies published through June 2006.

REVIEW METHODS

Included studies reported an association between maternal smoking during pregnancy and risk of overweight among children at least 2 years of age. We did not include in the meta-analysis studies that provided only a continuous measure of adiposity, although those studies are discussed separately.

RESULTS

Based on results of 84 563 children reported in 14 observational studies, children whose mothers smoked during pregnancy were at elevated risk for overweight (pooled adjusted odds ratio (OR) 1.50, 95% CI: 1.36, 1.65) at ages 3-33 years, compared with children whose mothers did not smoke during pregnancy. The pooled estimate from unadjusted odds ratios (OR 1.52, 95% CI: 1.36, 1.69) was similar to the adjusted estimate, suggesting that sociodemographic and behavioral differences between smokers and nonsmokers did not explain the observed association. Although we observed evidence for publication bias, simulating a symmetric set of studies yielded a similar estimate (OR 1.40, 95% CI: 1.26, 1.55).

CONCLUSIONS

Prenatal smoking exposure appears to increase rates of overweight in childhood. In parts of the world undergoing the epidemiologic transition, the continuing increase in smoking among young women could contribute to spiraling increases in rates of obesity-related health outcomes in the 21st century.

Genetic and environmental influences on body size in early childhood: a twin birth-cohort study

Genetic and environmental contributions to body size from birth to 5 years in a population-based twin cohort were studied. Sex differences in gene-environment etiology were also explored. Analyses used data from the Quebec Newborn Twin Study (QNTS), a population-based birth cohort of 672 twin pairs. The final sample consisted of 177 complete twin pairs. Heritability of weight was moderate at birth while common environmental factors accounted for almost half of the variance. Influence of family environment disappeared by 5 months and genetic effects were high (approximately 90%) for both sexes at 5 months and 5 years. Adjustment of weight for height yielded similar results as for weight alone. Slight but significant sex-limitation of genetic effects was observed at 5 months. Overall, genetic factors accounted for 40% of birthweight variance, with intrauterine environment influences explaining almost half. However, genetic factors accounted for most of the variance in weight. These results do not imply a lack of environmental effects on body weight, but rather a lack of: (1) environmental effects that are independent from genetic liability, and/or (2) a lack of significant environmental variation in the population (e.g., uniform nutritional habits) that leaves genetic differences between children to generate most of the variance in weight.

Importância da avaliação nutricional de recém-nascidos pré-termo por meio de relações antropométricas

OBJETIVO: Mostrar a importância das relações antropométricas na avaliação nutricional de prematuros de muito baixo peso (RNPTMBP), durante o primeiro mês de vida. MÉTODOS: Estudo longitudinal prospectivo incluindo RNPTMBP (peso ao nascer <1.500g e idade gestacional <37 semanas). Foram aferidos peso (P), comprimento (C) e perímetros braquial (PB) e cefálico (PC) e calculadas as relações antropométricas: índice ponderal (IP), índice de massa corporal (IMC) e razão PB/PC. A seguir, calcularam-se médias e desvios padrão das relações antropométricas, bem como a correlação entre parâmetros e relações antropométricas por meio do coeficiente de correlação de Pearson, nos três períodos do estudo (ao nascimento, 14 e 28 dias). RESULTADOS: Foram selecionados 55 recém-nascidos (54,5% do sexo feminino), com P ao nascer de 1.076,70+286,70g e idade gestacional de 30,70+2,10 semanas. O IP era, ao nascimento, 2,28+0,20, evoluindo para 2,00+0,20 (14 dias) e 2,17+0,20 aos 28 dias. O IMC mostrou: 8,20+1,10 (nascimento), 7,60+1,00 aos 14 e 8,60+1,20 aos 28 dias. A razão PB/PC encontrada foi de 0,21+0,02 ao nascimento, 0,19+0,02 aos 14 e 0,21+0,02 aos 28 dias. Dentre as correlações, o IP foi o de menor correlação, seguida pela razão PB/PC. O IMC apresentou alta correlação com os parâmetros antropométricos. CONCLUSÕES: IP, IMC e razão PB/PC apresentaram aumentos significantes entre 14 e 28 dias de vida, porém esta diferença não foi observada entre o nascimento e o 28º dia. Dentre as relações antropométricas, o IMC mostrou-se mais fidedigno, pois demonstrou crescimento real dos prematuros após a segunda semana, por ter superado os valores do nascimento.

Parent overweight predicts daughters' increase in BMI and disinhibited overeating from 5 to 13 years

OBJECTIVE

To assess whether parental overweight status and disinhibited overeating are predictive of daughters' accelerated weight gain and disinhibited overeating.

RESEARCH METHODS AND PROCEDURES

Participants were part of a longitudinal study of girls (N = 197) and their parents. Measured height and weight were used to calculate BMI [weight (kilograms)/height (meters)(2)]. Parents' disinhibited eating behavior was assessed using the Eating Inventory. Girls' disinhibited eating was assessed using a behavioral protocol to measure eating in the absence of hunger. Girls were classified based on parental overweight at study entry into four groups: neither, mother only, father only, or both parents overweight.

RESULTS

Girls with both parents overweight had the most rapid increases in BMI from 5 to 13 years of age; BMI increased most slowly among the neither parent overweight group, with intermediate increases in BMI among mother only and father only overweight groups. Daughters with both parents overweight at study entry were eight times more likely to be overweight at age 13, controlling for daughters' weight at age 5. Girls with both parents overweight had higher levels of disinhibited eating across all ages than all other groups. Although girls in all parental weight status groups showed increases in disinhibited eating over time, girls with both parents overweight had larger increases in disinhibited eating over time compared with all other groups.

DISCUSSION

Girls growing up in families differing in parental overweight had divergent developmental trajectories for BMI and disinhibited overeating. Findings reveal the need to focus prevention efforts on overweight parents of young children.

Body-composition assessment in infancy: air-displacement plethysmography compared with a reference 4-compartment model

BACKGROUND

A better understanding of the associations of early infant nutrition and growth with adult health requires accurate assessment of body composition in infancy.

OBJECTIVE

This study evaluated the performance of an infant-sized air-displacement plethysmograph (PEA POD Infant Body Composition System) for the measurement of body composition in infants.

DESIGN

Healthy infants (n = 49; age: 1.7-23.0 wk; weight: 2.7-7.1 kg) were examined with the PEA POD system. Reference values for percentage body fat (%BF) were obtained from a 4-compartment (4-C) body-composition model, which was based on measurements of total body water, bone mineral content, and total body potassium.

RESULTS

Mean (+/- SD) reproducibility of %BF values obtained with the PEA POD system was 0.4 +/- 1.3%. Mean %BF obtained with the PEA POD system (16.9 +/- 6.5%) did not differ significantly from that obtained with the 4-C model (16.3 +/- 7.2%), and the regression between %BF for the 4-C model and that for the PEA POD system (R2 = 0.73, SEE = 3.7%BF) did not deviate significantly from the line of identity (y = x).

CONCLUSIONS

The PEA POD system provided a reliable, accurate, and immediate assessment of %BF in infants. Because of its ease of use, good precision, minimum safety concerns, and bedside accessibility, the PEA POD system is highly suitable for monitoring changes in body composition during infant growth in both the research and clinical settings.

Early determinants of overweight at 4.5 years in a population-based longitudinal study

OBJECTIVES

The roots of the obesity epidemic need to be traced back as early in life as possible in order to develop effective means for preventing obesity and its health consequences in the future. The aim of this paper is to examine a broad range of factors that may simultaneously contribute to childhood overweight in a population-based cohort of children followed from birth to 4.5 years, to determine which factors exert the most influence in early life.

DESIGN

The analyses were performed using data from the Quebec Longitudinal Study of Child Development 1998-2002 (QLSCD).

SUBJECTS

The study follows a representative sample (n=2103) of children born in 1998 in the Canadian province of Quebec.

MEASURE

Measured height and weight were available for 1550 children aged 4.5 years. At 4.5 years, BMI was analyzed using the US CDC sex- and age-specific growth charts. In order to study children at their highest weights at various ages, odds ratios were presented for high birth weight, weight-for-stature at or above the 95th percentile at 5 months, and BMI at or above the 95th percentile at 4.5 years. Monthly weight gain between birth and five months has been analyzed. Children were also evaluated by the Z-score obtained from the standardized weight divided by height. Factors potentially related to children's weight include sex, gestational age and birth rank, breastfeeding, mothers' smoking status during pregnancy, family type at child's birth, and family income before pregnancy and when the children were 5 months and 4.5 years old. Other parental factors such as height and overweight/obesity (based on BMI) and other maternal factors (age, education, immigrant status) were also part of the analysis.

RESULTS

Being in the highest quintiles of weight gain between birth and 5 months, as well as maternal smoking during pregnancy, almost double the odds of being overweight at 4.5 years. Parental overweight or obesity also increased the odds of being overweight at this age, as well as being raised in middle-income or in poor families. A greater proportion of children born to nonsmoking mothers with higher weights (more than 4000 g) were overweight at 4.5 years, the percentage being greatest for those in the highest weight-gain categories from birth to 5 months. The pattern was different for children born to smoking mothers. The greatest proportion of 4.5-year-old overweight children was seen for children born in the normal weight-range category (3000-4000 g) who were in the highest quintiles of weight gain from birth to 5 months, and for children with high birth weights (more than 4000 g) who were in the lowest quintiles of birth-to-5-months weight gain. Children who were overweight at 4.5 years and who had been born to smoking mothers started life with a birth weight around that for the population means, but they gained more weight in the first 5 months of life than did the children of nonsmoking mothers.

CONCLUSION

This study indicates that behavioral and social factors exert critical influences on the onset of childhood overweight in preschool years. From a population-health perspective, interventions aimed at preventing childhood obesity would do well to target smoking pregnant women, as well as nonsmoking pregnant women at risk for giving birth to high-birth-weight children, paying particular attention to rapid weight gain in the first months of life.

Rapid infancy weight gain and subsequent obesity: systematic reviews and hopeful suggestions

In a systematic review, we identified 21 separate studies with data on the association between rapid infancy weight gain, up to age 2 y, and subsequent obesity risk. Uniformly all studies reported significant positive associations. We transformed the reported effect sizes to a standard infancy weight gain exposure, and found that further differences in study design accounted for much of the variation in risk. An accompanying paper by Melinda Yeung reminds us that there are benefits of postnatal catch-up growth in certain populations, and suggests that genetic and nutritional factors could moderate the unhealthy translation of rapid infancy weight gain to visceral fat and insulin resistance. Further evidence is needed, and we will need to rigorously test the benefits and risks of any interventions. However, the concept of "healthy" rapid catch-up infancy growth is an attractive prospect.

CONCLUSION

Rapid infancy weight gain is consistently associated with increased subsequent obesity risk, but the predictive ability of different weight gain cut-offs needs to be tested.

Relations between high ponderal index at birth, feeding practices and body mass index in infancy

OBJECTIVE

We compared feeding practices between infants of high ponderal index (PI) at birth (PI above the 90th percentile) and normal PI at birth (PI between 10th and 90th percentiles), and examined how birth size and infant feeding practices were related to body mass index (BMI) at 12 months.

DESIGN

In a cohort of 3000 infants invited to participate in a national Norwegian dietary survey, 1825 participated both at 6 and 12 months of age, and the present study included those born full term and with a PI (weight/length3) at birth > or =10th percentile (n=1441). Data on feeding practices were collected by food-frequency questionnaires, and anthropometrical data were measured by health-care personnel.

RESULTS

A lower proportion of infants born with high PI were exclusively breastfed for at least 4 months compared with infants born with normal PI (37 and 47%, respectively; P=0.03). Earlier introduction of solid foods and higher consumption of some foods were also observed among infants of high PI. In a multivariate analysis, adjusted mean BMI (kg/m2) at 12 months was higher for infants of high PI at birth than for infants of normal PI (17.6 and 17.0, respectively; P<0.001) and higher for infants exclusively breastfed <3 months than for infants exclusively breastfed > or =3 months (17.5 and 17.2, respectively; P=0.001).

CONCLUSIONS

High PI at birth was associated with a shorter duration of exclusive breastfeeding. Furthermore, high PI at birth and short-term exclusive breastfeeding were both associated with higher BMI at 12 months.

Weight gain in the first week of life and overweight in adulthood: a cohort study of European American subjects fed infant formula

BACKGROUND

Successful prevention of obesity and related cardiovascular risk factors requires a clear understanding of its determinants over the life course. Rapid infancy weight gain is associated with childhood obesity, whereas low infancy weight is associated with coronary heart disease. Our aim was to identify during which periods in infancy weight gain is associated with adult obesity.

METHODS AND RESULTS

A cohort of European American formula-fed subjects, measured on 7 occasions during infancy as part of several infant formula studies, were contacted at age 20 to 32 years, when they reported usual adult weight and height. A life-course plot was used to identify critical periods of weight gain associated with adulthood overweight (body mass index > or =25 kg/m2). These associations were tested with logistic regressions. Data were available for 653 subjects (72% of eligible subjects). Approximately 32% of them were overweight adults. The period between birth and age 8 days was identified as potentially critical. After adjustment for important confounding factors, weight gain during the first week of life was associated with adulthood overweight status (OR for each 100-g increase 1.28, 95% CI 1.08 to 1.52), as was weight gain during the first 112 days of life (OR 1.04, 95% CI 1.01 to 1.08). Similar results were obtained after standardization with z scores from a reference population.

CONCLUSIONS

In formula-fed infants, weight gain during the first week of life may be a critical determinant for the development of obesity several decades later. These results contribute to the understanding of chronic disease programming and suggest new approaches to obesity prevention.

Early growth and childhood obesity: a historical cohort study

OBJECTIVE

To investigate to what extent prenatal, early postnatal, and late postnatal growth predicts risk of childhood obesity.

METHODS

This was a historical cohort study of 1335 full term singletons born in southwest England in 1989. The main outcome measure was body mass index (BMI) at age 7. Absolute weights at birth, 6 weeks, and 18 months, and change in weights during the intervening periods were measured. Measures were examined as z scores standardised to the 1990 UK reference population.

RESULTS

BMI at age 7 was positively associated with z scores for weight at all ages. Regression coefficients (95% confidence intervals) were: 0.16 (0.11 to 0.22), 0.19 (0.15 to 0.24), and 0.29 (0.26 to 0.33) for weights at birth, 6 weeks, and 18 months, respectively. Regression coefficients for birth weight, early weight gain (change in weight z score between birth and 6 weeks), and late weight gain (change in weight z score between 6 weeks and 18 months), adjusted for each other were: 0.32 (0.27 to 0.38), 0.31 (0.26 to 0.37), and 0.28 (0.23 to 0.32), respectively. There was no statistical evidence for interaction among weights, weight gains, or social deprivation. Social deprivation independently predicted BMI at age 7, the major influence being weight gain after 6 weeks of life.

CONCLUSIONS

These data suggest that obesity risk is acquired gradually over the perinatal and postnatal periods, instead of during a prenatal or early postnatal critical window. The association of obesity risk with social circumstances and the timing of its origin offer pointers to some underlying determinants of obesity.

Rapid growth in infancy and childhood and obesity in later life--a systematic review

The association between obesity and morbidity resulting from chronic diseases is well known. This systematic review addresses studies of the role of rapid growth in infancy and childhood as possible determinants of overweight and obesity later in the life course. We reviewed MEDLINE for studies reporting on growth in infancy and childhood, as well as measures of weight or adiposity in later childhood, adolescence or adulthood. The methodological quality of the papers was assessed using the criteria suggested by Downs and Black. Sixteen articles that fulfilled review criteria were located. There was wide variability in the indicators used for defining rapid growth as well as overweight or obesity. The age range in which weight or adiposity was measured ranged from 3 to 70 years. In spite of differences in definitions used, 13 articles that reported on early rapid growth found significant associations with later overweight or adiposity. Efforts should be made to standardize the definition of rapid growth, as well as that of overweight and obesity in children and adolescents. The most frequent definition for rapid growth in this review was a Z-score change greater than 0.67 in weight for age between two different ages in childhood. Regarding obesity, the definition proposed by the International Obesity Task Force also appears to be most appropriate. The present results indicate that early growth is indeed associated with the prevalence of obesity later in the life course.

Distribution of adipose tissue in the newborn

Regional differences in adipose tissue distribution are associated with differences in adipocyte metabolism and obesity-related morbidities. Intrauterine growth restriction appears to place individuals at greater risk of obesity associated morbidities in later life. Despite this, little is known regarding the quantity and distribution of adipose tissue in infants during early development. The aim of this study was to compare total and regional adipose tissue content in appropriate-for-gestational-age (AGA) and growth-restricted (GR) newborn infants born at or near term. Whole body adipose tissue magnetic resonance imaging (MRI) was performed as soon as possible after birth. Total and regional adipose tissue depots were quantified. A total of 35 infants (10 GR; 25 AGA) were studied. Mean (SD) total percentage adipose tissue was lower in GR infants than AGA infants [GR: 17.70% (2.17); AGA: 23.40% (3.85); p = 0.003]. This difference arose from differences in subcutaneous adipose tissue mass [mean (SD) percentage subcutaneous adipose tissue mass, GR: 16.13% (2.20); AGA: 21.44% (3.81); p = 0.004], but not intra-abdominal adipose tissue mass [mean (SD) percentage intra-abdominal adipose tissue, GR: 0.42% (0.22); AGA: 0.61% (0.31); p = 0.45]. In contrast to subcutaneous adipose tissue, intra-abdominal adipose tissue is not reduced in infants with intrauterine growth restriction. This suggests that subcutaneous and intra-abdominal adipose tissue compartments may be under different regulatory control during intrauterine life.

Pediatric hypertension 2001

During the past decade, there has been a surge of interest in childhood and adolescent hypertension. The current review summarizes work published during the past year in the following areas: prenatal and early postnatal causes of hypertension; new information on the genetics of childhood hypertension; the relation of obesity, insulin resistance, and diabetes to hypertension; the use of ambulatory blood pressure monitoring to evaluate childhood hypertension; and advances in drug therapy for children with hypertension. The information obtained during the past year has improved our understanding of the pathogenesis, diagnosis, and treatment of childhood hypertension.