Prevalence and risk factors for overweight and obesity in children from Seychelles, a country in rapid transition: the importance of early growth

Birth weight and childhood obesity: effect modification by residence and household wealth

BACKGROUND

There are both genetic and environmental factors which contribute to a child's chances of being obese. When low birth weight (LBW) has been specifically evaluated relative to its association with childhood obesity, the results have produced conflicting findings. This study aims to describe the relationship between birth weight and childhood obesity and investigate the influence that residence and household wealth has on this relationship.

METHODS

I performed a secondary analysis on the 2013 Riskesdas (or Basic Health Research), a cross-sectional, nationally representative survey of the Indonesian population. Height, weight, information regarding child's birth weight, and basic characteristics of the study population were collected from parents with children aged 0 to 5 years (n = 63,237) in 2013. The exposure was child's birth weight and the outcomes were child's current weight, BMI z-score, and obesity. Data were analyzed by using multiple linear regression and multiple logistic regression.

RESULTS

I found a significant increase in the weight, BMI z-score, and risk of childhood obesity to be associated with LBW. LBW children in rural area were associated with higher BMI z-score (mean ± standard error: 1.44 ± 0.02) and higher odds (odds ratio (95% confidence interval): 7.46 (6.77-8.23)) of obesity than those in urban area. LBW children from low class families were associated with higher BMI z-score (1.79 ± 0.04) and had higher odds (14.79 (12.47-17.54)) of obesity than those from middle class and wealthy families.

CONCLUSIONS

Effective prevention and intervention to childhood obesity as early as possible are imperative. As far as this study was concerned, efforts, policies, and targets are required to reduce the prevalence of LBW. Children born of LBW, who live in a rural area and from low income families, should be emphatically intervened as early as possible.

Childhood overweight and obesity among the Saudi population: a case-control study among school children

BACKGROUND

Childhood obesity is a global public health concern with major consequences. In Saudi Arabia, the percentage of children who are overweight or obese has significantly increased in the past two decades, raising concerns about the physical and psychosocial consequences of this burden. This study aimed at investigating the different risk factors contributing to childhood obesity in Saudi Arabia.

METHODS

A case-control study was conducted among 492 school children (246 overweight/obese children, and 246 normal weight control children aged 5-9 years). Using valid and reliable instruments, parental and child characteristics, behavioral practices, screen use, and other activities were assessed as risk factors for childhood obesity using logistic regression analysis.

RESULTS

An unemployed father (OR=11.90; 95% CI: 7.47-18.93), a father with overweight/obesity (OR=2.04; 95% CI: 1.40-2.96), an incorrect parental perception of child's weight status (OR=2.54; 95% CI: 1.75-3.68), cesarean delivery (OR=2.52; 95% CI: 1.56-4.09), daily time in active play for less than 30 min (OR=2.18; 95% CI: 1.44-3.28), frequent snacking (OR=1.74; 95% CI: 1.05-2.93), and screen time use for more than 2 h per day outside of school (OR=1.62; 95% CI: 1.12-2.34) were all independent risk factors for being overweight or obese among the selected cases.

CONCLUSION

Efforts to prevent childhood overweight and obesity in this population should focus primarily on the early identification and confrontation of risk factors. Such risk factors include parental characteristics and awareness of the magnitude of the burden obesity poses, behavioral practices such as frequent snacking, screen time use, and physical activity.

Increasing prevalence of overweight among Seychelles children, 1998-2002

To examine the prevalence and trends in excess weight among children in the Seychelles. Serial surveys of weight and height were conducted each year between 1998-2002 in all students attending four school grades (crèche, 4^th, 7^th and 10^th years of compulsory school). Overweight and obesity were defined using age-specific body mass index (BMI) criteria of the International Obesity Task Force. Two questions explored physical activity at leisure time and daily walking time. From an eligible total of 32 077 observations between 1998-2002, data were available in 22 694 (71%), which corresponded to 17 627 separate children. Median age in the four grades was respectively 5.5, 9.2, 12.6, and 15.8 years. The overall prevalence of excess weight ('overweight' and 'obese' categories combined) was 10.5% in boys and 16.4% in girls. From 1998 to 2002, the prevalence of excess weight increased from 8.4% to 11.8% in boys and from 11.9% to 18.4% in girls. The increase of excess weight over calendar years was particularly marked among the younger children. Only a quarter of children reported walking at least 30minutes per day. Leisure physical activity was inversely associated with excess body weight. The prevalence of excess body weight was high among school children of Seychelles and increased substantially over a five-year period. This calls for prompt and energetic policies and programs to promote physical activity and healthy nutrition among children.

Weight gain in early years and subsequent body mass index trajectories across birth weight groups: a prospective longitudinal study

BACKGROUND

Rapid weight gain (RWG) in early-life is associated with increased risk of childhood obesity and is common among low-birth weight infants. Few studies have compared body mass index (BMI) trajectories of children experienced RWG to those who did not, across birth weight groups. We investigated the association between RWG in early-life and subsequent BMI trajectory and whether the association differs by birth weight.

METHODS

We included term singletons from the UK Millennium Cohort Study (n = 10 637). RWG was defined as an increase in weight z-scores (derived using UK-WHO growth reference) between birth and 3 years >0.67. Mixed-effect fractional polynomial models were applied to examine the association between RWG and BMI trajectories (5-14 years). Models were further adjusted for confounders and stratified by birth weight-for-gestational-age group.

RESULTS

Mean BMI trajectories were higher in children who experienced RWG in early-life, compared with their non-RWG counterparts. RWG was associated with higher BMI at five years [by 0.76 kg/m2 (95% CI: 0.67-0.85) in boys and 0.87 kg/m2 (0.76-0.97) in girls]; the difference persisted into adolescence [1.37 kg/m2 (1.17-1.58) and 1.75 kg/m2 (1.52-1.99) at 14 years, respectively]. Differences remained after adjustment and were particularly greater for children born large-for-gestational-age than those born small- and appropriate-for-gestational-age. Mean BMI trajectories for large-for-gestational-age children with RWG exceeded international reference curves for overweight (for obesity at some ages in girls).

CONCLUSIONS

RWG was associated with higher BMI trajectories throughout childhood and adolescence, especially in large-for-gestational-age children. Strategies for obesity prevention need to address factors during and before infancy and preventing excessive weight gain among infants who have already had adequate growth in utero.

Overweight/obesity and associated cardiovascular risk factors in sub-Saharan African children and adolescents: a scoping review

INTRODUCTION

Recently, childhood and adolescence overweight/obesity has increased disproportionately in developing countries, with estimates predicting a parallel increase in future cardiovascular disease (CVD) burden identifiable in childhood and adolescence. Identifying cardiovascular risk factors (CVRF) associated with childhood and adolescence overweight/obesity is pivotal in tailoring preventive interventions for CVD. Whilst this has been examined extensively in high-income countries, there is scant consistent or representative data from sub-Saharan Africa (SSA).

OBJECTIVE

This scoping review synthesises contemporary studies on CVRF associated with overweight and obesity in SSA children and adolescents to provide evidence on the current burden of overweight/obesity and CVD in this population.

METHODS

We searched MEDLINE and Google Scholar up to July 31, 2019 for observational and experimental studies and systematic reviews addressing childhood and adolescence overweight/obesity and CVRF in SSA without language restriction. Four investigators working in four pairs, independently selected and extracted the relevant data. The methodological quality of all included studies was assessed.

RESULTS

We included 88 studies with a total of 86,637children and adolescents from 20 SSA countries. The risk of bias was low in 62 (70.5%), moderate 18 (20.5%), and high in eight (9%) studies. Overweight/obesity in SSA children and adolescents is rising at an alarming rate. Its main associations include physical inactivity, unhealthy diets, high socio-economic status, gender and high maternal body mass index. Identified CVRF in overweight/obese SSA children and adolescents are mainly metabolic syndrome, hypertension, dyslipidaemia, diabetes and glucose intolerance. There is a dearth of guidelines or consensus on the management of either childhood overweight/obesity or CVRF in overweight/obese SSA children and adolescents.

CONCLUSION

The current findings suggest an urgent need to review current health policies in SSA countries. Health education and transforming the current obesogenic environment of the SSA child and adolescent into one which promotes physical activity and healthy dietary habits is required.

Relative Weight Gain Through Age 4 Years Is Associated with Increased Adiposity, and Higher Blood Pressure and Insulinemia at 4-5 Years of Age in Mexican Children

Background

Rapid early weight gain has been associated with increased risk of obesity and cardiometabolic alterations, but evidence in low and middle-income countries is inconclusive.

Objective

We evaluated the relation between relative weight gain from 1 to 48 mo with adiposity and cardiometabolic risk factors at 4-5 y of age, and determined if adiposity is a mediator for cardiometabolic alterations.

Methods

We studied 428 Mexican children with anthropometric and blood pressure (BP) information from birth to 5 y of age from POSGRAD (Prenatal Omega-3 fatty acid Supplementation and child GRowth And Development), of whom 334 provided measures of adiposity and cardiometabolic risk markers at 4 y. We estimated relative weight gain by means of conditional weight-for-height z scores for the age intervals 1-6, 6-12, 12-24, and 24-48 mo. Associations between relative weight gain and adiposity and cardiometabolic risk markers (lipid profile, triglycerides, insulin, glucose, and BP) were analyzed by multivariate multiple linear models and path analysis.

Results

A 1-unit increase in conditional weight-for-height z score within each age interval was positively associated with adiposity at 5 y, with coefficients of 0.43-0.89 for body mass index (BMI) z score, 1.08-3.65 mm for sum of skinfolds, and 1.21-3.87 cm for abdominal circumference (all P < 0.01). Positive associations were documented from ages 6 to 48 mo with systolic BP (coefficient ranges: 1.19-1.78 mm Hg; all P < 0.05) and from ages 12 to 48 mo with diastolic BP (1.28-0.94 mm Hg; P < 0.05) at 5 y. Conditional weight-for-height z scores at 12-24 and 24-48 mo of age were more strongly associated with adiposity and BP relative to younger ages. A unit increase in conditional weight-for-height z scores from 12 to 24 mo was associated with 14% higher insulin levels (P < 0.05) at 4 y. Path analyses documented that the associations of conditional weight gain with BP were mediated by BMI and sum of skinfolds.

Conclusion

Relative weight gain at most periods during the first 4 y of life was associated with greater adiposity and higher systolic and diastolic BP at 5 y. These associations with BP were mediated by adiposity. Relative weight gain from 12 to 24 mo was associated with increased serum insulin concentrations at 4 y, but there were no associations with lipid profiles or glucose concentration.

Childhood Health Outcomes in Term, Large-for-Gestational-Age Babies With Different Postnatal Growth Patterns

Large-for-gestational-age (LGA) babies have a higher risk of metabolic disease later in life, and their postnatal growth in early childhood may be associated with long-term adverse outcomes. This study aimed to determine childhood health outcomes of term LGA babies with different growth patterns. Data were obtained from the US Collaborative Perinatal Project for the years between 1959 and 1976. The growth trajectories of 3,316 term LGA babies were identified and odds ratios of obesity, growth restriction, low intelligence quotient (IQ), and high blood pressure (HBP) were calculated by logistic regression. Compared with term appropriate-for-gestational-age infants, term LGA babies without catch-down growth had increased risks of obesity (adjusted odds ratio (aOR) = 6.37, 95% confidence interval (CI): 5.24, 7.73) and HBP (aOR = 1.67, 95% CI: 1.37, 2.03). Those with high catch-down growth had higher risks of growth restriction (aOR = 2.21, 95% CI: 1.66, 2.95) and low IQ (aOR = 1.61, 95% CI: 1.04, 2.49). Nevertheless, infants with small catch-down growth had lower risks of obesity (aOR = 0.78, 95% CI: 0.63, 0.95), growth restriction (aOR = 0.28, 95% CI: 0.17, 0.46), low IQ (aOR = 0.66, 95% CI: 0.41, 1.06), and HBP (aOR = 0.89, 95% CI: 0.77, 1.04). According to our data, term LGA infants with small catch-down growth had no increased risks of adverse outcomes.

Birth weight and type 2 diabetes: A meta-analysis

The prevalence of T2DM is increasing around the world on a yearly basis. A meta-analysis was conducted to analyze the association between birth weight and incidence of type 2 diabetes mellitus (T2DM). A literature search was performed from January 1990 to June 2016 in PubMed, ScienceDirect, SpringerLink, China National Knowledge Infrastructure and Chinese Biomedical Literature Database. After reviewing characteristics of all the included studies systematically, a meta-analytical method was employed to calculate the pooled odds ratios (ORs) and associated 95% confidence intervals (CI) from random-effects models. Heterogeneity was assessed by Q-statistic test. Funnel plot, Begg's and Egger's linear regression tests were applied to evaluate publication bias. A sensitivity analysis was also performed to assess the robustness of results. According to inclusion and exclusion criteria, 8 studies were selected to be included in the meta-analysis. Compared with normal birth weight (2,500–4,000 g), low birth weight (<2,500 g) was associated with an increased risk of T2DM (OR, 1.55; 95% CI, 1.39–1.73; P<0.001). No significant difference was observed between high birth weight (>4,000 g) and normal birth weight in terms of the risk of T2DM (OR, 0.98; 95% CI, 0.79–1.22). Compared with high birth weight, low birth weight was associated with an increased risk of diabetes mellitus (OR, 1.58; 95% CI, 1.30–1.93; P<0.001). These findings indicated that there may be an inverse linear association between birth weight and T2DM.

Gestational Diabetes – Metabolic Risks of Adult Women With Respect to Birth Weight

Metabolic disorders such as obesity, insulin resistance and other components of metabolic syndrome (MetS) are connected with birth weight. Low and high birth weight is associated with a higher risk of developing type 2 diabetes mellitus, the mechanism is not clear. In this study, we evaluated the association between birth weight and anthropometric as well as biochemical components of MetS in women with a history of gestational diabetes mellitus (GDM) in comparison with control women. In part of the GDM group, we re-evaluated metabolic changes over 5-8 years. Anthropometry, blood pressure, glucose metabolism during the 3-h oGTT, lipid profile, uric acid, thyroid hormones, and liver enzymes were assessed. From the analyzed components of MetS in adult women we proved the association of low birth weight (birth weight <25th percentile) with glucose processing, in particular among women with a history of GDM. Low birth weight GDM women revealed significantly higher postchallenge insulin secretion and lower peripheral insulin sensitivity. Re-examinations indicate this association persists long after delivery.

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.

The optimal postnatal growth trajectory for term small for gestational age babies: a prospective cohort study

OBJECTIVES

To identify an optimal growth trajectory for term small for gestational age (SGA) babies from birth to 7-years-old.

STUDY DESIGN

Data were from the Collaborative Perinatal Project, a US multicenter prospective cohort study from 1959-1976. Five weight growth trajectories of the 1957 term SGA babies were grouped by a latent class model. We selected the optimal growth pattern based on the lowest overall risks of childhood diseases.

RESULTS

Compared with appropriate for gestational age children, SGA babies with no catch-up growth (439, 22.4%) had higher risks of infection in infancy (aOR 1.2, 95% CI 1.0-1.6), growth restriction (11.2, 8.6-14.6), and low IQ (2.1, 1.7-2.8) at age 7 years. Those with excessive catch-up growth (176, 8.9%) had higher risks of overweight/obesity (7.5, 5.4-10.5) and elevated blood pressure (1.7, 1.1-2.4) at age 7 years. Babies with slow catch-up growth (328, 16.8%) or regression after 4 months (285, 14.6%) were associated with higher risks of low IQ (1.6, 1.2-2.1) and growth restriction (2.2, 1.5-3.2), respectively. Only babies with appropriate catch-up growth (729, 37.3%) did not have increased risk of adverse outcomes. Further, we also tested linear growth trajectories with similar findings.

CONCLUSIONS

The optimal growth trajectory for term SGA infants may be fast catch-up growth to about the 30th percentile in the first several months, with modest catch-up growth thereafter, to be around the 50th percentile by 7-years-old.

Testing a capacity-load model for hypertension: disentangling early and late growth effects on childhood blood pressure in a prospective birth cohort

BACKGROUND

In 2005, it was estimated that hypertension affected 26.4% of the adult population worldwide. By 2025, it is predicted that it will affect about 60% of adults, a total of 1.56 billion. Both pre- and postnatal growth patterns have been associated with later blood pressure (BP), but in contrasting directions. These inconsistent associations of growth during different developmental periods merit elucidation. We tested a theoretical model treating birth weight as a marker of homeostatic metabolic capacity, and childhood height, lean mass and fat mass as independent indices of metabolic load. We predicted that decreased capacity and increased load would be independently associated with increased BP.

METHODS AND FINDINGS

Data from the ALSPAC cohort on growth from birth to 7 years, and body composition by dual-energy X-ray absorptiometry and BP at 9 years, were analysed (n = 6579). Data were expressed as standard deviation scores (SDS) or standardised regression residuals (SRR). BP was independently and positively associated with each of height, lean mass and fat mass. In a joint model systolic BP was positively associated with conditional weight velocity [males 0.40 (95%CI: 0.37-0.44) & females 0.44 (95%CI: 0.40-0.47) SDS/SRR], but not birth weight [0.00 (95%CI: -0.03-0.04) & 0.03 (95%CI: -0.01-0.07) SDS/SDS]. Adjusting for height, lean mass and fat mass, the association of systolic BP and conditional weight velocity attenuated [0.00(95%CI: -0.09-0.08) & -0.06(95%CI: -0.14-0.03) SDS/SRR], whereas that with birth weight became negative [-0.10 (95%CI: -0.14-0.06) & -0.09 (95%CI: -0.13-0.05) SDS/SDS]. Similar results were obtained for diastolic BP and pulse pressure.

CONCLUSIONS

Consistent with our theoretical model, high metabolic load relative to metabolic capacity is associated with increased BP. Our data demonstrate the contribution of different growth and body composition components to BP variance, and clarify the developmental aetiology of hypertension.

Birth weight and long-term overweight risk: systematic review and a meta-analysis including 643,902 persons from 66 studies and 26 countries globally

BACKGROUND

Overweight is among the major challenging health risk factors. It has been claimed that birth weight, being a critical indicator of prenatal developmental conditions, is related to long-term overweight risk. In order to check this important assumption of developmental and preventive medicine, we performed a systematic review and comprehensive meta-analysis.

METHODS AND FINDINGS

Relevant studies published up to January 2011 that investigated the relation between birth weight and later risk of overweight were identified through literature searches using MEDLINE and EMBASE. For meta-analysis, 66 studies from 26 countries and five continents were identified to be eligible, including 643,902 persons aged 1 to 75 years. We constructed random-effects and fixed-effects models, performed subgroup-analyses, influence-analyses, assessed heterogeneity and publication bias, performed meta-regression analysis as well as analysis of confounder adjusted data. Meta-regression revealed a linear positive relationship between birth weight and later overweight risk (p<0.001). Low birth weight (<2,500 g) was found to be followed by a decreased risk of overweight (odds ratio (OR) =0.67; 95% confidence interval (CI) 0.59-0.76). High birth weight (>4,000 g) was associated with increased risk of overweight (OR=1.66; 95% CI 1.55-1.77). Results did not change significantly by using normal birth weight (2,500-4,000 g) as reference category (OR=0.73, 95% CI 0.63-0.84, and OR=1.60, 95% CI 1.45-1.77, respectively). Subgroup- and influence-analyses revealed no indication for bias/confounding. Adjusted estimates indicate a doubling of long-term overweight risk in high as compared to normal birth weight subjects (OR=1.96, 95% CI 1.43-2.67).

CONCLUSIONS

Findings demonstrate that low birth weight is followed by a decreased long-term risk of overweight, while high birth weight predisposes for later overweight. Preventing in-utero overnutrition, e.g., by avoiding maternal overnutrition, overweight and/or diabetes during pregnancy, might therefore be a promising strategy of genuine overweight prevention, globally.

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.

Association between socioeconomic status indicators and obesity in adolescent students in Botswana, an African country in rapid nutrition transition

OBJECTIVE

The purpose of this study was to examine two separate socioeconomic status (SES) indicators of obesity in Botswana, an African country that has experienced rapid economic development and where the prevalence of human immunodeficiency virus/acquired immune deficiency syndrome is high.

METHODS

We conducted a nationally representative, cross-sectional study of 707 adolescent secondary school students in Botswana. Measured height and weight were used to compute World Health Organization age- and sex-specific body mass index z-scores. SES was described by private vs. public school attendance and a survey of assets/facilities within the home.

RESULTS

Overall, private school students and those with more assets had a higher prevalence of overweight and obesity than public school students (private: 27.1%, 95% confidence interval [CI]: 20.4-34.5; public: 13.1%, 95% CI: 9.8-16.8) and those with fewer assets (more assets: 20.0%, 95% CI: 16.0-24.4; fewer assets: 11.2%, 95% CI: 6.6-16.9).

CONCLUSIONS

Public health interventions in developing countries may need to be targeted differently to low or high SES individuals in order to treat already high obesity rates in higher SES groups and to prevent the development of obesity in lower SES communities undergoing economic transition.

Birth weight, weight change, and blood pressure during childhood and adolescence: a school-based multiple cohort study

OBJECTIVE

We assessed the association between birth weight, weight change, and current blood pressure (BP) across the entire age-span of childhood and adolescence in large school-based cohorts in the Seychelles, an island state in the African region.

METHODS

Three cohorts were analyzed: 1004 children examined at age 5.5 and 9.1 years, 1886 children at 9.1 and 12.5, and 1575 children at 12.5 and 15.5, respectively. Birth and 1-year anthropometric data were gathered from medical files. The outcome was BP at age 5.5, 9.1, 12.5 or 15.5 years, respectively. Conditional linear regression analysis was used to estimate the relative contribution of changes in weight (expressed in z-score) during different age periods on BP. All analyses were adjusted for height.

RESULTS

At all ages, current BP was strongly associated with current weight. Birth weight was not significantly associated with current BP. Upon adjustment for current weight, the association between birth weight and current BP tended to become negative. Conditional linear regression analyses indicated that changes in weight during successive age periods since birth contributed substantially to current BP at all ages. The strength of the association between weight change and current BP increased throughout successive age periods.

CONCLUSION

Weight changes during any age period since birth have substantial impact on BP during childhood and adolescence, with BP being more responsive to recent than earlier weight changes.

Prediction of childhood obesity by infancy weight gain: an individual-level meta-analysis

To assess the predictive ability of infant weight gain on subsequent obesity we performed a meta-analysis of individual-level data on 47,661 participants from 10 cohort studies from the UK, France, Finland, Sweden, the US and Seychelles. For each individual, weight SD scores at birth and age 1 year were calculated using the same external reference (British 1990). Childhood obesity was defined by International Obesity Task Force criteria. Each +1 unit increase in weight SD scores between 0 and 1 year conferred a twofold higher risk of childhood obesity (odds ratio = 1.97 [95% confidence interval (CI) 1.83, 2.12]), and a 23% higher risk of adult obesity (odds ratio = 1.23 [1.16, 1.30]), adjusted for sex, age and birthweight. There was little heterogeneity between studies. A risk score for childhood obesity comprising weight gain 0-1 year, mother's body mass index, birthweight and sex was generated in a random 50% selection of individuals from general population cohorts with available information (n = 8236); this score showed moderate predictive ability in the remaining 50% sample (area under receiving operating curve = 77% [95% CI 74, 80%]). A separate risk score for childhood overweight showed similar predictive ability (area under receiving operating curve = 76% [73, 79%]). In conclusion, infant weight gain showed a consistent positive association with subsequent obesity. A risk score combining birthweight and infant weight gain (or simply infant weight), together with mother's body mass index and sex may allow early stratification of infants at risk of childhood obesity.

Body size and growth in 0- to 4-year-old children and the relation to body size in primary school age

Excess weight in early life is believed to increase susceptibility to obesity, and in support of such theory, excess weight and fast weight gain in early childhood have been related to overweight later in life. The aim of this study was to review the literature on body size and growth in 0- to 4-year-old children and the association with body size at age 5-13 years. In total, 43 observational studies on body size and/or growth were included, of which 24 studies had been published in 2005 or later. Twenty-one studies considered body size at baseline, and 31 studies considered growth which all included assessment of weight gain. Eight (38%) studies on body size, and 15 (48%) on weight gain were evaluated as high-quality studies. Our results support conclusions in previous reviews of a positive association between body size and weight gain in early childhood, and subsequent body size. Body size at 5-6 months of age and later and weight gain at 0-2 years of age were consistently positively associated with high subsequent body size. Results in this review were mainly based on studies from developed Western countries, but seven studies from developing countries showed similar results to those from developed countries.

Prevalence of thinness in children and adolescents in the Seychelles: comparison of two international growth references

BACKGROUND

Thinness in children and adolescents is largely under studied, a contrast with abundant literature on under-nutrition in infants and on overweight in children and adolescents. The aim of this study is to compare the prevalence of thinness using two recently developed growth references, among children and adolescents living in the Seychelles, an economically rapidly developing country in the African region.

METHODS

Weight and height were measured every year in all children of 4 grades (age range: 5 to 16 years) of all schools in the Seychelles as part of a routine school-based surveillance program. In this study we used data collected in 16,672 boys and 16,668 girls examined from 1998 to 2004. Thinness was estimated according to two growth references: i) an international survey (IS), defining three grades of thinness corresponding to a BMI of 18.5, 17.0 and 16.0 kg/m2 at age 18 and ii) the WHO reference, defined here as three categories of thinness (-1, -2 and -3 SD of BMI for age) with the second and third named "thinness" and "severe thinness", respectively.

RESULTS

The prevalence of thinness was 21.4%, 6.4% and 2.0% based on the three IS cut-offs and 27.7%, 6.7% and 1.2% based on the WHO cut-offs. The prevalence of thinness categories tended to decrease according to age for both sexes for the IS reference and among girls for the WHO reference.

CONCLUSION

The prevalence of the first category of thinness was larger with the WHO cut-offs than with the IS cut-offs while the prevalence of thinness of "grade 2" and thinness of "grade 3" (IS cut-offs) was similar to the prevalence of "thinness" and "severe thinness" (WHO cut-offs), respectively.

Velocidade de ganho de peso nos primeiros anos de vida e excesso de peso entre 5-11 anos de idade, Salvador, Bahia, Brasil

Crianças com sobrepeso estão mais propensas a se tornarem adultos com sobrepeso ou obesos, sendo a prevenção mais eficaz a intervenção em fases precoces da vida. Analisou-se a associação entre ganho de peso nos primeiros anos de vida e sobrepeso/obesidade em 1.056 crianças menores de 11 anos de idade. Foram coletadas informações relacionadas ao estilo de vida, saneamento, condições socioeconômicas, peso ao nascer e aleitamento materno. O ganho de peso do nascimento até diferentes intervalos (até 12 meses, > 12 a 18, > 18 a 24, e > 24 a 60 meses) foi considerado de forma contínua em escores-z. Foi considerado excesso de peso o índice de massa corporal (IMC) maior ou igual a +1 escore-z, usando referências da Organização Mundial da Saúde (OMS) de 2006 e 2007. Adotou-se a regressão linear e Poisson multivariada. A velocidade do ganho ponderal mostrou-se associada ao IMC, observando-se duas vezes mais sobrepeso/obesidade a cada incremento de uma unidade no desvio-padrão da velocidade do ganho ponderal para o intervalo de 24 e 60 meses (RR = 2,08; IC95%: 1,87-2,32). Encontrou-se associação entre o rápido ganho de peso em todos os intervalos de idade e a ocorrência de sobrepeso/obesidade anos mais tarde.

Breast-feeding and growth in children until the age of 3 years: the Generation R Study

Breast-feeding has been suggested to be associated with lower risks of obesity in older children and adults. We assessed whether the duration and exclusiveness of breast-feeding are associated with early postnatal growth rates and the risks of overweight and obesity in preschool children. The present study was embedded in a population-based prospective cohort study from early fetal life onwards, among 5047 children and their mothers in The Netherlands. Compared with children who were breast-fed, those who were never breast-fed had a lower weight at birth (difference 134 (95 % CI - 190, - 77) g). No associations between breast-feeding duration and exclusivity with growth rates before the age of 3 months were observed. Shorter breast-feeding duration was associated with an increased gain in age- and sex-adjusted standard deviation scores for length, weight and BMI (P for trend < 0·05) between 3 and 6 months of age. Similar tendencies were observed for the associations of breast-feeding exclusivity with change in length, weight and BMI. Breast-feeding duration and exclusivity were not consistently associated with the risks of overweight and obesity at the ages of 1, 2 and 3 years. In conclusion, shorter breast-feeding duration and exclusivity during the first 6 months tended to be associated with increased growth rates for length, weight and BMI between the age of 3 and 6 months but not with the risks of overweight and obesity until the age of 3 years.

Peso ao nascer e obesidade em crianças e adolescentes: uma revisão sistemática

OBJETIVO: Verificar o nível de evidência científica e epidemiológica da hipótese de associação entre peso ao nascer e sobrepeso/obesidade na infância e na adolescência, a partir de revisão sistemática da literatura. MÉTODO: Foi realizada revisão sistemática nas bases MedLine/Pubmed, Scielo-Brasil e Lilacs. Adaptou-se a escala de Downs & Black para avaliar a qualidade metodológica dos catorze artigos selecionados. Os artigos foram classificados em duas categorias de análise, de acordo com o índice de desenvolvimento humano do país onde o estudo foi realizado: a) peso ao nascer e sobrepeso/obesidade em países com desenvolvimento humano elevado; e b) peso ao nascer e sobrepeso/obesidade em países com desenvolvimento humano elevado, mas ainda ascendente, e com desenvolvimento humano médio. RESULTADOS: Em ambas as categorias predominou a associação entre elevado peso ao nascer e sobrepeso/obesidade. Além disso, na primeira categoria, um dos sete artigos mostrou que o baixo peso ao nascer foi preditor de maior percentual de gordura corporal e abdominal. Na segunda categoria, três artigos mostraram associação do catch-up growth com sobrepeso/obesidade, e um mostrou o baixo peso ao nascer como fator protetor do sobrepeso (incluindo obesidade). Foram capturados quatro artigos brasileiros, dentre os quais dois não identificaram associação estatisticamente significativa entre peso ao nascer e sobrepeso/obesidade. CONSIDERAÇÕES FINAIS: O elevado peso ao nascer apareceu associado ao sobrepeso/obesidade na maioria dos artigos. Há necessidade de se continuar investigando sobre a associação entre o baixo peso ao nascer e sobrepeso/obesidade.

Prevalence and risk factors of overweight and obesity among urban school children in Elazig city, Eastern Turkey, 2007

BACKGROUND

The prevalence of obesity is increasing dramatically all over the world. Very little data are currently available on the prevalence of childhood obesity in Turkey, and more research on the risk factors is required before preventive public health programmes can be put into practice.

AIM

The aim of this study is to determine the prevalence of overweight and obesity and related factors in primary school students in Elazig, a city in eastern Turkey.

SUBJECTS AND METHODS

In March-June 2007 a cross-sectional study of children aged 6-11 years old was performed. A total of 1782 girls and 1860 boys were observed. Weight and height were measured. Overweight and obesity using age- and sex-specific body mass index (BMI) cut-off points as defined by the International Obesity Taskforce were used.

RESULTS

Prevalence of overweight and obesity were 13.2% and 1.6%, respectively. According to gender, the prevalence of obesity in boys was 2.0% and overweight was 13.9%, while in girls, obesity was 1.2% and overweight was 12.5%. We found that overweight and obesity may be related to factors such as eating while watching television, and eating fast food.

CONCLUSION

It was noted as a health problem that there are overweight students aged between 6 and 11 years attending primary schools in Elazig province.

Inappropriate bottle use: an early risk for overweight? Literature review and pilot data for a bottle-weaning trial

Identifying early risk factors for childhood obesity is critical, as weight in infancy and early childhood tracks to later periods. Continued bottle use - primarily from excess milk intake - is emerging as a potential risk factor for early childhood overweight. Over three fourths of US infants drink from bottles beyond the recommended weaning age of 12 months, and two thirds of UK infants use a bottle at 18 months. This paper is divided into three parts. Part 1 reviews the literature on beverage intake, weight and bottle use in young children. Part II describes pilot data on milk bottle use and weight in 12-60-month-olds, collected prior to a randomized controlled (RCT) trial of a bottle-weaning intervention. Median daily milk bottle consumption at 12 months was 5.0 (interquartile range = 3-6). Among 12-36-month-olds, current users were significantly more likely to be >95th% weight-for-height (19% vs. 0%, P < 0.02), and more were >85% weight-for-height (27% vs. 11%, P < 0.11), vs. non-users. In contrast, current bottle use was not associated with either overweight or obesity in 37-60-month-olds. Part III describes the RCT, begun in fall 2008. It is enrolling 464 parent/12-month-old dyads from a nutrition assistance programme for low-income families. Children's bottle use, anthropometrics, dietary intake and nutrient density (via 24 h recall) are assessed quarterly through 24 months of age. For the intervention, site nutritionists employ a project-developed, visually attractive flip chart. An observational study nested within the RCT will describe dietary changes during this period of feeding transitions.

Roles, perceptions and control of infant feeding among low-income fathers

OBJECTIVE

Introduction of solid foods before the recommended age of 4-6 months is a common practice in the USA, and appears to be especially prevalent among infants who are enrolled in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Currently, little is known about how fathers influence early infant feeding decisions, outside the decision to breast- or formula-feed. The purpose of the current study was to explore how fathers perceive the role they play in feeding and caring for their infants.

DESIGN

Participants were twenty-one male caregivers, who were fathers or partners of the mothers of WIC income-eligible infants residing in two rural East Tennessee counties. In-depth, audio-taped telephone interviews were completed. Interviews were transcribed, coded and analysed according to standard grounded theory procedures to identify emergent concepts. These concepts were explored and linked together to become themes.

RESULTS

Three themes emerged: (i) fathers' roles; (ii) fathers' perceptions; and (iii) control. Concepts within the theme of fathers' roles included physical and emotional support for both mother and infant, validation of maternal decisions, and financial support. In the present study, fathers' perceptions were primarily shaped by their own experiences, advice from those with experience, and information sought by the fathers. The theme of control appears to be the linkage between the fathers' attempts to modify infant behaviour and infants' response.

CONCLUSIONS

A final conceptual model was created to explain the interrelated nature of the themes and may be helpful to those who work with fathers and/or families of new infants.

Infant weight gain, duration of exclusive breast-feeding and childhood BMI – two similar follow-up cohorts

Objective

To describe the association between duration of exclusive breast-feeding (EBF), weight gain in infancy and childhood BMI in two populations with a long duration of EBF.

Design

Cohort study with follow-up in childhood. Breast-feeding status was reported monthly during infancy. Weight and length were measured at birth, 2, 6 and 12 months of age, as well as in childhood at 6 or 10 years of age.

Setting

Iceland and Denmark.

Subjects

Randomly selected healthy newborns from Denmark (n 85) and Iceland (n 100).

Results

Infants exclusively breast-fed for ≤2 months gained 348 (95% CI 69, 626) g more weight from 2 to 6 months than infants exclusively breast-fed for 3–4 months (P = 0·009). Weight gain from 6 to 12 months was found to be greater among infants exclusively breast-fed for ≤2 months compared with those exclusively breast-fed for ≥5 months (P = 0·008). A greater weight change, in terms of Z-score, between the ages of 2 and 6 months was associated with higher Z-score of childhood BMI, adjusted for birth weight, country and duration of EBF (B = 0·49, se = 0·11, P < 0·001, adj. R2 = 0·15). However, the association was much stronger in the Icelandic cohort than the Danish one.

Conclusions

Although duration of EBF was not associated with childhood BMI in the present study it may modulate growth rate in infancy, which is related to childhood BMI. However, other factors determinative for infant growth also need to be considered when assessing the relationship of early growth and nutrition to childhood overweight, as traditions in complementary food might differ between populations.

Contribution of early weight gain to childhood overweight and metabolic health: a longitudinal study (EarlyBird 36)

BACKGROUND

Early weight gain (0-5 years) is thought to be an important contributor to childhood obesity and consequently metabolic risk. There is a scarcity of longitudinal studies in contemporary children reporting the impact of early weight gain on metabolic health.

OBJECTIVE

We aimed to assess the impact of early weight gain on metabolic health at 9 years of age.

METHOD

Two hundred thirty-three children (134 boys, 99 girls) with a gestational age of >37 weeks were assessed at birth, 5 years of age, and 9 years of age. Measures included weight SD scores at each time point and excess weight gained (Delta weight SD score) between them. The outcome measure included composite metabolic score (sum of internally derived z scores of insulin resistance, mean blood pressure, triglyceride level, and total cholesterol/high-density lipoprotein cholesterol ratio).

RESULTS

Weight SD score increased by 0.29 SD score in girls and 0.26 SD score in boys from 0 to 5 years of age and by 0.03 SD score in girls and 0.11 SD score in boys from 5 to 9 years of age. Weight SD score correlated poorly to moderately before 5 years of age but strongly after 5 years of age. Birth weight SD score predicted (girls/boys) 2.4%/0% of the variability in composite metabolic score at 9 years of age. Adding Delta weight SD score (0-5 years old) contributed (girls/boys) 11.2%/7.0% to the score, and adding Delta weight SD score (5-9 years old) additionally contributed (girls/boys) 26.4%/16.5%. Importantly, once weight SD score at 9 years of age was known, predictive strength was changed little by adding Delta weight SD score.

CONCLUSIONS

Most excess weight before puberty is gained before 5 years of age. Weight at 5 years of age bears little relation to birth weight but closely predicts weight at 9 years of age. Single measures of current weight are predictive of metabolic health, whereas weight gain within a specific period adds little. A single measure of weight at 5 years of age provides a pointer to future health for the individual. If metabolic status at 9 years of age means future risk, diabetes/cardiovascular prevention strategies might better focus on preschool-aged children, because the die seems to be largely cast by 5 years of age, and a healthy weight early in childhood may be maintained at least into puberty.

Associations of birthweight and infant growth with body composition at age 15--the COMPASS study

Size at birth and postnatal growth have been positively associated with obesity in adulthood. However, associations between postnatal growth and body composition later in life have rarely been studied. The overall purpose was to explore the associations between birthweight, weight gain during first year of life and height, weight, body mass index, fat free mass index (FFMI), fat mass index, % fat mass (FM) and waist circumference in adolescence. The COMPASS study is a population-based study of adolescents from a well-defined area in Stockholm County, Sweden. Birth characteristics and weight during childhood were collected from registers and child health centre records, and body composition at age 15 years was measured by bioelectric impedance by trained nurses. Complete data were available for 2453 adolescents. Associations between predictor and outcome variables were assessed with linear regression modelling. Birthweight was positively associated with all outcome variables, except for %FM among girls. FFMI increased by 0.49 kg/m(2)[95% CI 0.34, 0.63] (boys) and 0.25 kg/m(2)[0.12, 0.38] (girls) per 1 SD increase in birthweight. Increased weight gain in infancy showed strong, positive associations with all measures of body composition. FFMI increased by 0.73 kg/m(2)[0.60, 0.87] (boys) and 0.63 kg/m(2)[0.50, 0.76] (girls) per unit increase in weight z-score during first year of life. The effect of increased weight gain in infancy was not modified by birthweight. Birthweight and postnatal growth were both positively related to body composition in adolescence. Increased weight gain during the first year of life had stronger effect than prenatal growth, suggesting infancy to be a more critical period.

Programming of body composition by early growth and nutrition

There is now compelling evidence that growth patterns in early life are associated with risk of the metabolic syndrome in adulthood, although the relative importance of prenatal v. postnatal growth for such associations remains controversial. Body composition may play a key role in the ‘programming’ of such diseases, through itself being programmed by early growth, and perhaps also by being a mediator of the programming process. Early studies reporting positive associations between birth weight and adult BMI suggested a tendency for large babies to become obese adults. Such findings appeared contradictory to the many studies linking low birth weight with increased risk of the metabolic syndrome. Recent studies now indicate that birth weight is strongly predictive of later lean mass, and has a much weaker association with later fatness. Studies that link low birth weight with a more central adipose distribution in later life remain controversial, and require confirmation using more sophisticated methodologies. Findings for infant growth rate appear population-specific, with infant weight gain predicting subsequent lean mass in developing countries, but predicting subsequent fat mass and obesity in industrialised populations. Further studies are required on this issue, to ensure that appropriate public health policies are recommended for countries across the range of economic development. Although the links between early growth and later disease risk implicate early-life nutrition, either in utero or during infancy, few prospective studies have explored the influence of early diet on later body composition. Many studies have associated breast-feeding with a reduced prevalence of obesity categorised by BMI; however, the few studies directly evaluating childhood fatness provide little support for this hypothesis. Recent advances in the ability to measure body composition during the infant period offer a major opportunity to improve the understanding of the nutritional programming of body composition and its contribution, or lack thereof, to subsequent disease risk.

Trends and sociocultural factors for childhood overweight in La Reunion Island

OBJECTIVE

To examine time trends (study 1) and sociocultural factors associated with childhood overweight (study 2) in La Reunion Island.

DESIGN

Study 1: a longitudinal analysis of anthropometric data available from health services in the town of Saint-Pierre. Study 2: a case - control study.

SUBJECTS

Study 1: 1753 children born between 1977 and 1996. Study 2: 101 six-year old overweight children sex-matched with 101 non-overweight children.

MEASUREMENTS

Study 1: overweight at birth (birth weight>4 kg) and at age 4 and 6 using French references and references from the International Obesity Task Force. Study 2: parental and perinatal data, child's lifestyle and representation of food, all collected from the mother.

RESULTS

Study 1: a dramatic increase in the prevalence rate of overweight at 4 and at 6 is observed, more severe in girls. Study 2: multivariate logistic regressions showed that mother's overweight was the only variable significantly associated with overweight in both the sexes. The other associated factors were related to sociocultural and family features and sedentarity. Logistic probability functions derived from these data are proposed as a tool for detection of at risk families.

CONCLUSION

Our results show the need for a targeted prevention of overweight. We offer a proposal based on education and behaviour modification in La Reunion Island.

Obesity amongst affluent adolescent girls

OBJECTIVE

To assess the prevalence and type of obesity in affluent schoolgirls aged 16 and 17 yr.

METHODS

A cross-sectional study was conducted in 2002, in 4 randomly selected public schools of Delhi. All girls from randomly chosen classes were included. Weight, height and waist and hip circumferences were measured for all 414 schoolgirls and their socio-demographic profile was recorded. Body mass index [BMI] and waist hip ratio [WHR] were calculated for all the girls. BMI > 30 (i.e.--95th percentile) denotes obesity and BMI > 25 (i.e.--85th percentile) denotes overweight as according to International Obesity Task Force (IOTF) criteria. WC > 80 cm or WHR > 0.85 denote central obesity.

RESULTS

Prevalence of obesity and overweight amongst the study subjects was 5.3% and 15.2% respectively (IOTF). Out of the 22 obese girls central obesity was present in 21 girls (95.4%) [WC > 80 cm] and 12 girls (54.5%) [WHR > 0.85].

CONCLUSION

There is significant prevalence of obesity in affluent schoolgirls in Delhi and more than half of them have central obesity.

Protein intake during the period of complementary feeding and early childhood and the association with body mass index and percentage body fat at 7 y of age

BACKGROUND

A high protein intake during infancy and early childhood has been proposed to increase the risk of subsequent obesity.

OBJECTIVE

We analyzed the association of different protein intakes during 6-24 mo with body mass index (BMI; in kg/m2) and percentage body fat (%BF) at 7 y of age.

DESIGN

The analyses included 203 participants of the DOrtmund Nutritional and Longitudinally Designed (DONALD) Study with complete information on early diet (6, 12, and 18-24 mo) and anthropometric data at the age of 7 y. The median of energy-adjusted protein intakes (in g/d) was used to distinguish different patterns of low and high protein intakes throughout the first 2 y of life, which were then related to BMI SD scores (SDSs), %BF, and the risk of overweight and overfatness at 7 y of age.

RESULTS

Although protein intake at 6 mo of age was not associated with the outcomes, a consistently high protein intake at the ages of 12 and 18-24 mo was independently related to a higher mean BMI SDS and %BF at the age of 7 y [BMI SDS: 0.37 (95% CI: 0.12, 0.61) compared with 0.08 (95% CI: -0.09, 0.26), P = 0.04; %BF: 18.37 (95% CI: 17.29, 19.51%) compared with 16.91 (95% CI: 16.19, 17.66%), P = 0.01] and a higher risk of having a BMI or %BF above the 75th percentile at that age [odds ratio for BMI: 2.39 (95% CI: 1.14, 4.99), P = 0.02); odds ratio for %BF: 2.28 (95% CI: 1.06, 4.88), P = 0.03].

CONCLUSIONS

High protein intakes during the period of complementary feeding and the transition to the family diet are associated with an unfavorable body composition at the age of 7 y.

Breast-feeding and risk for childhood obesity: does maternal diabetes or obesity status matter?

OBJECTIVE

We sought to evaluate whether maternal diabetes or weight status attenuates a previously reported beneficial effect of breast-feeding on childhood obesity.

RESEARCH DESIGN AND METHODS

Growing Up Today Study (GUTS) participants were offspring of women who participated in the Nurses' Health Study II. In the present study, 15,253 girls and boys (aged 9-14 years in 1996) were included. Maternal diabetes and weight status and infant feeding were obtained by maternal self-report. We defined maternal overweight as BMI > or = 25 kg/m2. Childhood obesity, from self-reported height and weight, was based on the Centers for Disease Control and Prevention definitions as normal, at risk for overweight, or overweight. Maternal status categories were nondiabetes/normal weight, nondiabetes/overweight, or diabetes. Logistic regression models used generalized estimating equations to account for nonindependence between siblings.

RESULTS

For all subjects combined, breast-feeding was associated with reduced overweight (compared with normal weight) in childhood. Compared with exclusive use of formula, the odds ratio (OR) for exclusive breast-feeding was 0.66 (95% CI 0.53-0.82), adjusted for age, sex, and Tanner stage. Results did not differ according to maternal status (nondiabetes/normal weight OR 0.73 [95% CI 0.49-1.09]; nondiabetes/overweight 0.75 [0.57-0.99]; and diabetes 0.62 [0.24-1.60]). Further adjustment for potential confounders attenuated results, but results remained consistent across strata of maternal status (P value for interaction was 0.50).

CONCLUSIONS

Breast-feeding was inversely associated with childhood obesity regardless of maternal diabetes status or weight status. These data provide support for all mothers to breast-feed their infants to reduce the risk for childhood overweight.

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.

Early and late weight gain and the timing of puberty

Nutrition is an important regulator of the tempo of growth and obesity is usually associated with tall childhood stature and earlier pubertal development. Several longitudinal studies have demonstrated that timing of puberty is most closely linked to infancy weight gain: suggesting an early window for programming of growth and development. Earlier puberty in the UK MRC 1946 birth cohort was related to smaller size at birth and rapid growth between 0 and 2 years. Rapid early weight gain leads to taller childhood stature and higher insulin-like growth factor I (IGF-I) levels, possibly through early induction of growth hormone (GH) receptor numbers, and such children are also at risk of childhood obesity. In the Avon Longitudinal Study of Parents and Children, rapid infancy weight gain was associated with increased risk of obesity at 5 and 8 years, with evidence of insulin resistance, exaggerated adrenarche and reduced levels of sex hormone binding globulin (SHBG). Potentially the elevated IGF-I and adrenal androgen levels, increased aromatase activity and increased 'free' sex steroid levels consequent to lower SHBG levels could all promote activity of the GnRH pulse generator. In addition obese children have higher leptin levels, a proven permissive factor in initiating LH pulsatility. Obesity could also affect the rate of progression through puberty as nutrition and SHBG may act respectively as an accelerator and brake on peripheral sex steroid action. Early weight gain and early pubertal development might also be associated with loss of the pubertal growth spurt perhaps through obesity-related suppression of GH secretion. Trans-generational recurrence of low birth weight, early catch-up weight gain, earlier menarche, and shorter adult stature have been observed in women, and could contribute to the strong heritability in age at menarche.

Non-Hispanic white and Hispanic elementary school children's self-regulation of energy intake

BACKGROUND

Preschool-aged children consistently self-regulate energy intake by adjusting food intake to reflect the energy density of the diet. However, only select adults demonstrate self-regulation skills related to energy density cues.

OBJECTIVE

The objective was to examine the developmental characteristics of non-Hispanic white and Hispanic children's self-regulation of energy intake and to determine whether individual differences in the precision of food intake regulation were related to the children's anthropometric measures.

DESIGN

Three hundred forty-two 5-12-y-old children were recruited from 2 schools, one school that enrolled predominantly non-Hispanic white children (n = 148) and another school in a Hispanic neighborhood (n = 194). The children ate 2-part meals, which consisted of a preload and a main meal. The preloads were fruit-flavored drinks that were either high (625 kJ) or low (12.5 kJ) in energy density. The children's food intake at the meal was measured and energy intake was estimated. An eating Compensation Index (COMPX) score, which reflected the children's ability to regulate energy intake, was used to predict the children's adiposity.

RESULTS

Both non-Hispanic white and Hispanic children showed evidence of incomplete compensation, with a mean (+/-SEM) COMPX score of 48.6 +/- 6.4%. No significant ethnicity or sex differences in the children's overall COMPX scores were observed; however, the children's COMPX scores decreased with age (P < 0.05). Maternal body mass index was the best predictor of the children's weight status.

CONCLUSION

Children aged 5-12 y show individual variation in their responsiveness to energy density cues; the responsiveness declines with increasing age.

Burden of overweight in Germany: prevalence differences between former East and West German children

BACKGROUND

Given the increasing prevalence of childhood overweight, we aimed to quantify the population burden and evaluate potential regional differences in anthropometric characteristics and prevalence of overweight in fourth graders in two German cities.

METHODS

Data were analysed from a cross-sectional school-based study conducted in 1995-96 in Dresden (former East Germany) and Munich (former West Germany) as part of the International Study of Asthma and Allergies in Childhood. Height and weight of the children were measured, and the parents completed a questionnaire. 2474 children age 9-10 years provided anthropometric data. Overweight was defined based on the age-specific and gender-specific international cut-off values for body mass index.

RESULTS

Dresden children were on average 1.2 kg lighter and >1 cm taller than their Munich peers. The prevalence of overweight in Dresden was 15.2% in girls and 14.2% in boys compared with 24 and 22.2%, respectively, in Munich. Differences were observed between Dresden and Munich with respect to the proportion of children of non-German nationality, household smoking, breastfeeding practices, and individual dietary behaviours. Even in combination these factors were not able to explain entirely the between-city overweight differences.

CONCLUSIONS

A substantial proportion of pre-adolescent children in Germany is now considered overweight with marked regional differences in prevalence. Comparison of population-level factors indicate that other unmeasured determinants of overweight may be responsible for the marked differences in the prevalence of overweight.

Fetal, infant and childhood growth: relationships with body composition in Brazilian boys aged 9 years

BACKGROUND

Early growth rate has been linked to later obesity categorised by body mass index (BMI), but the development of body composition has rarely been studied.

METHODS

We tested the hypotheses that (1) birthweight and weight gain in (2) infancy or (3) childhood are associated with later body composition, in 172 Brazilian boys followed longitudinally since birth. Growth was assessed using measurements of weight and height at birth, 6 months, and 1 and 4 y. Measurements at 9 y comprised height, weight and body composition using foot-foot impedance.

RESULTS

Birthweight was associated with later height and lean mass (LM), but not fatness. Weight gain 0-6 months was associated with later height and LM, and with obesity prevalence according to BMI, but not with fatness. Weight gain 1-4 y was associated with later fatness and LM. Weight gain 4-9 y was strongly associated with fatness but not LM. Early growth rate did not correlate positively with subsequent growth rate.

CONCLUSIONS

Early rapid weight gain increased the risk of later obesity, but not through a direct effect on fatness. Childhood weight gain remained the dominant risk factor for later obesity. The reported link between early growth and later obesity may be due partly to hormonal programming, and partly to the contribution of LM to obesity indices based on weight and height. Whether our findings apply to other populations requires further research.

Dietary energy intake at the age of 4 months predicts postnatal weight gain and childhood body mass index

OBJECTIVE

Rapid infant weight gain has been shown to predict later obesity risk; however, it is unclear which factors influence infant diet and weight gain. The objective of this study was to determine whether different feeding patterns and energy intakes that are provided to infants affect body weight and BMI later in childhood.

METHODS

This representative birth cohort study was conducted in the United Kingdom. Energy intake at age 4 months was estimated from 1-day unweighed dietary records in 881 infants and related to their childhood weight gain and BMI.

RESULTS

Among formula- or mixed-fed infants (N = 582), energy intake was higher in first-born infants (mean +/- SE: 2730 +/- 29.4 kJ/day; n = 263) than in subsequent-born infants (2620.8 +/- 25.2 kJ/day; n = 296). Energy intake at 4 months was also higher in infants who were given solid foods earlier (1-2 months: 2805.6 +/- 50.4 kJ/day, n = 89; 2-3 months: 2658.6 +/- 25.2 kJ/day, n = 339; 4+ months: 2587.2 +/- 46.2 kJ/day, n = 111). Higher energy intake at 4 months predicted greater weight gain between birth to age 1, 2, or 3 years and larger body weight and BMI at ages 1 to 5 years. No significant associations were seen in breastfed infants (N = 299).

CONCLUSIONS

Among formula- or mixed-fed infants, dietary energy intake at age 4 months predicted postnatal weight gain and childhood obesity risk. Both prenatal and postnatal factors may influence infant energy intake and postnatal weight gain.

Upward weight percentile crossing in infancy and early childhood independently predicts fat mass in young adults: the Stockholm Weight Development Study (SWEDES)

BACKGROUND

Rapid early postnatal weight gain predicts increased subsequent obesity and related disease risks. However, the exact timing of adverse rapid postnatal weight gain is unclear.

OBJECTIVE

The objective was to examine the associations between rapid weight gain in infancy and in early childhood in relation to body composition at age 17 y.

DESIGN

This prospective cohort study was conducted in 248 (103 males) singletons and their mothers. Height and weight were measured at birth, 6 mo, and 3 and 6 y. The rates of weight gain during infancy (0-6 mo) and early childhood (3-6 y) were calculated as changes in sex- and age-adjusted weight SD scores during these time periods. At 17 y, body composition was measured by air-displacement plethysmography.

RESULTS

Increasing weight gain during infancy and early childhood were both independently associated with larger body mass index, fat mass, relative fat mass, fat-free mass, and waist circumference at 17 y (P < 0.005 for all; adjusted for sex, birth weight, gestational age, current height, maternal socioeconomic status, and maternal fat mass). Rapid weight gain in infancy, but not in early childhood, also predicted taller height at 17 y (P < 0.001).

CONCLUSIONS

Rapid weight gain in both infancy and early childhood is a risk factor for adult adiposity and obesity. Rapid weight gain in infancy also predicted taller adult height. We hypothesize that rapid weight gains in infancy and early childhood are different processes and may allow separate opportunities for early intervention against obesity risk later in life.

Babies Born Small for Gestational Age: Insulin Sensitivity and Growth Hormone Treatment

Epidemiological studies have identified an association between size at birth and adult risk for type 2 diabetes mellitus and cardiovascular disease. In contemporary populations, children who are relatively small at birth and show rapid infancy weight gain are at greatest risk for the development of childhood obesity, increased visceral fat and insulin resistance: possible early markers of adult disease risk. Individuals presenting to growth clinics with short stature and a history of low birthweight will not have shown post-natal catch-up growth and may be a very heterogeneous group. Nevertheless, there are some data to suggest that as a group they are insulin resistant with decreased lean mass. Growth hormone treatment leads to reversible worsening of the insulin resistance, and short-term data do not indicate an increased risk for type 2 diabetes. However, further long-term follow-up is required, and particular care should be taken in monitoring children with a strong family history of type 2 diabetes and those from ethnic groups in which there is a high background prevalence of the disease.

Children at high risk for overweight: a classification and regression trees analysis approach

OBJECTIVE

Early identification of children at high risk for childhood overweight is a major challenge in fighting the obesity epidemic. We tried to identify the most powerful set of combined predictors for childhood overweight at school entry.

RESEARCH METHODS AND PROCEDURES

A classification and regression trees analysis on risk factors for childhood overweight in 4289 children 5 to 6 years of age participating in the obligatory school entry health examination 2001/2002 in Bavaria, Germany, was performed. Parental questionnaires asked for children's weight at birth and 2 years, breastfeeding history, maternal smoking in pregnancy, parental education, parental overweight/obesity, nationality, and number of older siblings. Overweight was defined according to sex- and age-specific BMI cut-points proposed by the International Obesity Task Force.

RESULTS

Prevalence of overweight was 11% among the entire study population. Although high early weight gain >10,000 grams was found in about one-half of the overweight children, its positive predictive value reached only 25%, indicating that one of four children with a high early weight gain is overweight at school entry. The best reliable set of predictors included high early weight gain and obese parents and accounted for a likelihood ratio of 3.6, with a corresponding positive predictive value of 40%, and was found in 4% of all children.

DISCUSSION

A combination of predictors available at 2 years of age could improve predictability of overweight at school entry. However, corresponding low positive predictive values indicate a precision of the prediction that might be insufficient for targeting intervention programs for identified high-risk children.