Underweight in the First 2 Years of Life and Growth in Later Childhood

IMPORTANCE

Few studies have examined the association between underweight in the first 2 years and growth in later childhood in high-income countries.

OBJECTIVE

To evaluate the associations of underweight in the first 2 years of life with body mass index (calculated as weight in kilograms divided by height in meters squared) z score (zBMI), weight-for-age z score (WAZ), and height-for-age z score (HAZ) from ages 2 to 10 years.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study was conducted between February 2008 to September 2020 in The Applied Research Group for Kids! practice-based research network in Toronto, Canada. Participants included healthy children aged 0 to 10 years. Data were analyzed from October 2020 to December 2021.

EXPOSURES

Underweight (ie, zBMI less than -2, per the World Health Organization) in the first 2 years of life.

MAIN OUTCOMES AND MEASURES

The primary outcome was zBMI from ages 2 to 10 years. Linear mixed-effects models were used to account for multiple growth measures over time.

RESULTS

A total of 5803 children were included in the primary analysis. At baseline, the mean (SD) age was 4.07 (5.62) months, 2982 (52.2%) were boys, and 550 children (9.5%) were underweight. Underweight in the first 2 years was associated with lower zBMI (difference, -0.39 [95% CI, -0.48 to -0.31]) at 10 years and lower HAZ (difference, -0.24 [95% CI, -0.34 to -0.14]) at age 2 years. Stratified by sex, at age 10 years, girls and boys with underweight in the first 2 years both had lower zBMI (girls: difference, -0.47 [95% CI, -0.59 to -0.34]; boys: difference, -0.32 [95% CI, -0.44 to -0.20]). At age 10 years, children with underweight and a lower zBMI growth rate in the first 2 years had lower zBMI (difference, -0.64 [95% CI, -0.77 to -0.53) and HAZ (difference, -0.12 [-0.24 to -0.01]), while children with underweight and a higher zBMI growth rate in the first 2 years had similar zBMI (difference, -0.11 [95% CI, -0.22 to 0.001]) and higher HAZ (difference, 0.16 [95% CI, 0.05 to 0.27]) compared with children who did not have underweight in the first 2 years.

CONCLUSIONS AND RELEVANCE

In this prospective cohort study, children with underweight in the first 2 years of life had lower zBMI and HAZ in later childhood. These associations were attenuated among children with a higher growth rate in the first 2 years.

Weight-for-height is associated with an overestimation of thinness burden in comparison to BMI-for-age in under-5 populations with high stunting prevalence

BACKGROUND

Thinness at <5 years of age, also known as wasting, is used to assess the nutritional status of populations for programmatic purposes. Thinness may be defined when either weight-for-height or body-mass-index-for-age (BMI-for-age) are below -2 SD of the respective World Health Organization standards. These definitions were compared for quantifying the burden of thinness.

METHODS

Theoretical consequences of ignoring age were evaluated by comparing, at varying height-for-age z-scores, the age- and sex-specific cut-offs of BMI that would define thinness with these two metrics. Thinness prevalence was then compared in simulated populations (short, intermediate and tall) and real-life data sets from research and the National Family Health Survey-4 (NFHS-4) in India.

RESULTS

In short (-2 SD) children, the BMI cut-offs with weight-for-height criteria were higher in comparison to BMI-for-age after 1 year of age but lower at earlier ages. In Indian research and NFHS-4 data sets (short populations), thinness prevalence with weight-for-height was lower from 0.5 to 1 years but higher at subsequent ages. The absolute difference (weight-for-height - BMI-for-age) for 0.5-5 years was 4.6% (15.9-11.3%) and 2.2% (19.2-17.0%), respectively; this attenuated in the 0-5 years age group. The discrepancy was higher in boys and maximal for stunted children, reducing with increasing stature. In simulated data sets from intermediate and tall populations, there were no meaningful differences.

CONCLUSIONS

The two definitions produce cut-offs, and hence estimates of thinness, that differ with the age, sex and height of children. The relative invariance, with age and stature, of the BMI-for-age thinness definition favours its use as the preferred index for programmatic purposes.

Body Mass Index Z Score vs Weight-for-Length Z Score in Infancy and Cardiometabolic Outcomes at Age 8-10 Years

OBJECTIVES

To confirm that World Health Organization weight-for-length z scores (zWFL) and World Health Organization body mass index z scores (zBMI) in infancy are associated with adiposity and cardiometabolic measures at 8-10 years old and to compare the predictive ability of the 2 methods.

STUDY DESIGN

zWFL and zBMI at 6, 12, and 18 months of age were computed using data extracted from health booklets, among participants in the Québec Adipose and Lifestyle InvesTigation in Youth prospective cohort (n = 464). Outcome measures at 8-10 years included adiposity, lipid profile, blood pressure, and insulin dynamics. The relationships between zWFL, zBMI, and each outcome were estimated using multivariable linear regression models. Outcome prediction at 8-10 years was compared between the 2 methods using eta-squared and the Lin concordance correlation coefficient.

RESULTS

zWFL and zBMI were associated with all measures of adiposity at 8-10 years. Associations with other cardiometabolic measures were less consistent. For both zWFL and zBMI across infancy, eta-squared were highly similar and the Lin coefficients were markedly high (≥0.991) for all outcomes.

CONCLUSIONS

There was no evidence that zBMI and zWFL in infancy differed in their ability to predict adiposity and cardiometabolic measures in childhood. This lends support to the sole use of zBMI for growth monitoring and screening of overweight and obesity from birth to 18 years.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03356262.

Mid-pregnancy PM2.5 exposure affects sex-specific growth trajectories via ARRDC3 methylation

Prenatal particulate matter <2.5 μm (PM_2.5) is associated with adverse birth growth. However, the longitudinal growth impacts have been little studied, and no mechanistic relationships have been described. We investigated the association between prenatal PM_2.5 exposure and growth trajectories, and the possible role of epigenetics. We enrolled 1313 neonates with PM_2.5 data measured by ordinary kriging from the COhort for Childhood Origin of Asthma and allergic diseases, followed up at 1, 3, and 5 years to evaluate growth. Differential DNA methylation and pyrosequencing of cord blood leukocytes was evaluated according to the prenatal PM_2.5 levels and birth weight (BW). PM_2.5 exposure during the second trimester (T2) caused the lowest BW in both sexes, further adjusted for indoor PM_2.5 levels [female, aOR 1.39 (95% CI 1.05-1.83); male, aOR 1.36 (95% CI 1.04-1.79)]. Bayesian distributed lag models with indoor PM_2.5 adjustments revealed a sensitive window for BW effects at 10-26 weeks gestation, but only in females. Latent class mixture models indicated that a persistently low weight-for-height percentile trajectory was more prevalent in the highest PM_2.5 exposure quartile at T2 in females, compared to a persistently high trajectory (36.5% vs. 20.3%, P = 0.022). Also, in the females only, the high PM_2.5 and low BW neonates showed significantly greater ARRDC3 methylation changes. ARRDC3 methylation was also higher only in females with low weight at 5 years of age. Higher fetal PM_2.5 exposure during T2 may cause a decreased growth trajectory, especially in females, mediated by ARRDC3 hyper-methylation-associated energy metabolism.

Model to estimate abdominal wall thickness in children undergoing placement or replacement of gastrostomy devices

OBJECTIVES

Abdominal wall thickness (AWT) is a key measurement when placing or replacing low profile gastrostomy devices. This measurement varies, depending on nutritional status and body habitus. We developed a mathematical model to estimate AWT using a compendium of body measurements.

METHODS

Ultrasonography was used to measure AWT at the initial gastrostomy site in subjects aged 22 days to 24 years old. Other body measurements (height, weight, waist circumference and distance from xiphisternum to pubis) were also obtained. Multiple linear regression was used to develop two separate models using age of 2 years to separate the groups. For analysis, AWT is log transformed.

RESULTS

Data from 97 subjects were used for analysis. The final model for those ≤24 months old is the following: ln(Estimated AWT) = -1.255 + 0.082*(1 if age 3-24 months, 0 if <3 months) + 0.022*(waist circumference in cm). The final model for those >24 months old is the following: ln(Estimated AWT) = -1.335 + 0.271*(1 if age >84 months, 0 if 24-84 months) + 0.082*(BMI) CONCLUSION: This model to estimate AWT is useful for determining the length of a gastrostomy device at initial placement and with subsequent changes. More data are needed to refine and further validate the model.

LEVEL OF EVIDENCE

Level IV, study of prognostic test.

Differences in growth of Canadian children compared to the WHO 2006 Child Growth Standards

BACKGROUND

To evaluate if there are departures from the WHO Child Growth Standards (WHO-CGS) in postnatal growth of healthy 'Canadian' children in Ontario up to age 2 years, including by infant feeding and ethnicity.

METHODS

We included data on 9964 healthy, singleton children born in Ontario, Canada. Smoothed weight, length and body mass index (BMI) percentile curves were generated using quantile regression for the Canadian cohort from birth to age 2 years. Differences in percentile values were calculated comparing Canadian children vs. the WHO-CGS.

RESULTS

Canadian children under age 2 years were longer than the WHO-CGS at the 10th (0.8 cm), 50th (1.3 cm) and 90th (1.9 cm) percentiles. Canadian children incrementally surpassed the WHO-CGS in weight after age 6 months, and in BMI after 9 months. By age 2 years, the 50th percentile weight of Canadian males was 823 g (95% confidence interval (CI) 680, 965) higher than the WHO-CGS 50th percentile. Weight differences were seen regardless of feeding practice, and were greatest among children of mothers born in Canada and Europe/Western nations, and least for those of East Asian/Pacific or South Asian heritage. Among Canadian breastfed males, 18% (95% CI 16, 19) of newborns and 26% (95% CI 20, 33) toddlers aged 2 years were classified by WHO-CGS as weighing >90th percentile - much higher than the expected rate of 10%. Similarities were seen for differences in BMI.

CONCLUSIONS

Healthy Canadian infants/toddlers are longer and heavier than the WHO-CGS norms. Explanations for these discrepancies require further elucidation.

BMI-for-Age and Weight-for-Length in Children 0 to 2 Years

OBJECTIVES

To determine the agreement between weight-for-length and BMI-for-age in children 0 to <2 years by using research-collected data, examine factors that may affect agreement, and determine if agreement differs between research- and routinely collected data.

METHODS

Cross-sectional data on healthy, term-born children (n = 1632) aged 0 to <2 years attending the TARGet Kids! practice-based research network in Toronto, Canada (December 2008-October 2014) were collected. Multiple visits for each child were included. Length (cm) and weight (kg) measurements were obtained by trained research assistants during research visits, and by nonresearch staff during all other visits. BMI-for-age z-scores were compared with weight-for-length z-scores (the criterion measure).

RESULTS

The correlation between weight-for-length and BMI-for-age was strong (r = 0.986, P < .0001) and Bland-Altman plots revealed good agreement (difference = -0.08, SD = 0.20, P = .91). A small proportion (6.3%) of observations were misclassified and most misclassifications occurred near the percentile cutoffs. There were no differences by age and sex. Agreement was similar between research- and routinely collected data (r = 0.99, P < .001; mean difference -0.84, SD = 0.20, P = .67).

CONCLUSIONS

Weight-for-length and BMI-for-age demonstrated high agreement with low misclassification. BMI-for-age may be an appropriate indicator of growth in the first 2 years of life and has the potential to be used from birth to adulthood. Additional investigation is needed to determine if BMI-for-age in children <2 years is associated with future health outcomes.

Childhood Obesity Incidence in the United States: A Systematic Review

BACKGROUND

This systematic review synthesizes the literature on incidence of obesity during childhood.

METHODS

We searched PubMed, Excerpta Medica database (EMBASE), and Cumulative Index to Nursing and Allied Health Literature (CINAHL), and used the Web of Science tool in June 2015. Studies were included if they were published in English, presented results from primary or secondary analyses, used data about children in the US, provided obesity incidence data on children 0 to 18 years born after 1970, and did not pertain to clinically defined populations (disease, medication use, etc.). Author(s), study year, study design, location, sample size, age, and obesity incidence estimates were abstracted.

RESULTS

Nineteen studies were included, three of which used nationally representative data. The median study-specific annual obesity incidences among studies using U.S. Centers for Disease Control and Prevention (CDC) growth charts were 4.0%, 3.2%, and 1.8% for preschool (2.0-4.9 years), school aged (5.0-12.9 years), and adolescence (13.0-18.0 years), respectively. This pattern of declining obesity incidence with age was consistent between and within studies.

CONCLUSIONS

Studies of childhood obesity in the US indicate declining incidence with age. Childhood obesity prevention efforts should be targeted to ages before obesity onset. Longitudinal data and consistent obesity definitions that correlate with long-term morbidity are needed to better characterize the life history of obesity.

Comparing the Use of Centers for Disease Control and Prevention and World Health Organization Growth Charts in Children with Cystic Fibrosis through 2 Years of Age

OBJECTIVE

To examine differences between use of World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC) growth reference in children with cystic fibrosis (CF) up to 2 years of age.

STUDY DESIGN

Growth from 1-24 months in 2587 children, born 2003-2006 and recorded in the US CF Foundation Registry, was evaluated using WHO and CDC references.

RESULTS

In both boys and girls with CF aged 1-24 months, use of WHO charts resulted in ∼8 percentile lower length-for-age and ∼13% higher short stature rate (length-for-age <5th percentile). WHO weight-for-age was ∼9 percentile lower prior to age 6 months, crossed at 6-7 months, and remained ∼14 percentile higher at 8-24 months. WHO weight-for-length (WFL) percentile (WFLp) was similar before 12 months but ∼10 percentile higher at 12-24 months compared with CDC. When using WHO charts, 9% of children had underweight (WFLp <50th) classified differently and this rate varied with age: 4% in the first year, 7% at 12, 13% at 15, and 16% at 18 months, respectively. Weight status assessed by WHO body mass index (BMI) charts was different from WHO WFL charts. At 24 months when switching back to CDC, 26% of children with normal WFLp on WHO charts appeared underweight on CDC charts. A 70th percentile of WHO BMI percentile was equivalent to the 50th percentile CDC BMI percentile.

CONCLUSIONS

Growth status in children with CF differed when using WHO and CDC references, particularly during the second year of life. These differences need to be considered for all uses of growth assessment in CF.

Adipose tissue dysregulation and metabolic consequences in childhood and adolescent obesity: potential impact of dietary fat quality

Evidence suggests that at a population level, childhood and adolescent obesity increase the long-term risk of chronic diseases such as type 2 diabetes and CVD. At an individual level, however, the metabolic consequences of obesity in youth vary immensely. Despite comparable BMI, some adolescents develop impaired glucose tolerance while others maintain normal glucose homeostasis. It has been proposed that the variation in the capacity to store lipid in the subcutaneous adipose tissue (SAT) may partially discriminate metabolically healthy from unhealthy obesity. In positive energy balance, a decreased capacity to expand SAT may drive lipid accumulation to visceral adipose tissue, liver and skeletal muscle. This state of lipotoxicity is associated with chronic low-grade inflammation, insulin resistance and dyslipidaemia. The present review examines the differential adipose tissue development and function in children and adolescents who exhibit metabolic dysregulation compared with those who are protected. Additionally, the role of manipulating dietary fat quality to potentially prevent and treat metabolic dysfunction in obesity will be discussed. The findings of the present review highlight the need for further randomised controlled trials to establish the effect of dietary n-3 PUFA on the metabolic phenotype of obese children and adolescents. Furthermore, using a personalised nutrition approach to target interventions to those at risk of, or those with established metabolic dysregulation may optimise the efficacy of modifying dietary fat quality.

Neglect: failure to thrive and obesity

Medical providers need to monitor growth at every visit. Weight status is influenced by genetics, medical conditions, socioeconomic status, and family environment. Screening for food security and psychosocial risk factors is an integral tool to identify families at risk for nutritional deficits and child maltreatment. Nutritional rehabilitation is best accomplished in an outpatient, multidisciplinary setting. Medical neglect should be considered in failure to thrive and obesity when there is a serious risk of harm from identified medical complications, additional or worsening medical complications occurring despite a multidisciplinary approach, and/or non-adherence with the treatment plan.

The contribution of feeding mode to obesogenic growth trajectories in American Samoan infants

What is already known about this subject Samoan adults are recognized for their particularly high body mass index and prevalent obesity. While Polynesians are understudied, in other populations infancy is a critical period in the development of obesity. Breastfeeding has been shown to attenuate obesity risk. What this study adds Samoan infants show remarkably rapid gain in weight but not length in early infancy resulting in a prevalence of overweight and obesity far higher than has been previously reported elsewhere. Breastfeeding is associated with slower weight gain in infancy suggesting that its protective benefits for obesity risk are generalizable outside of European-derived populations.

BACKGROUND

Samoans are recognized for their particularly high body mass index and prevalent adult obesity but infants are understudied.

OBJECTIVE

To examine the prevalence of overweight and obesity and determine the contribution of feeding mode to obesogenic growth trajectories in American Samoan infants.

METHODS

Data were extracted from the well baby records of 795 (n = 417 male) Samoan infants aged 0-15 months. Mixed-effects growth models were used to produce individual weight and length curves. Further mixed-effects models were fitted with feeding mode (breastfed, formula- or mixed-fed) as a single observation at age 4 (±2) months. Weight and length values were converted to z-scores according to the Centers for Disease Control 2000 reference.

RESULTS

At 15 months, 23.3% of boys and 16.7% of girls were obese (weight-for-length > 95th percentile). Feeding mode had a significant effect on weight and length trajectories. Formula-fed infants gained weight and length faster than breastfed infants. Formula-fed boys were significantly more likely to be obese at 15 months (38.6%) than breastfed boys (23.4%), χ(2)  = 8.4, P < 0.01, odds ratio = 2.05, 95% confidence interval (1.04, 4.05).

CONCLUSION

Obesity in American Samoans is not confined to adults. Obesity prevention efforts should be targeted at early life and promotion of breastfeeding may be a suitable intervention target.

The impact of growth curve changes in assessing premature infant growth

OBJECTIVE

To assess the impact of using the recently published WHO growth standard, based on healthy, breastfed infants in multiple countries that excluded prematurely born infants, versus the Infant Health Development Program (IHDP) growth reference constructed from premature infants, on the interpretation of the growth of premature infants after hospital discharge.

STUDY DESIGN

A retrospective cohort was constructed of infants born at gestational age ≤35 weeks who initially presented for care at one of the 32 outpatient sites between 2006 and 2008 (N=2297). Kappa statistics measured overall agreement and agreement in ever classifying infants <5th percentile or ≥ 95th percentile for age between the WHO and IHDP. Logistic regression models identified factors associated with growth curve disagreement in classifying infants at the extremes of growth.

RESULT

The WHO and IHDP growth curves showed moderate agreement for all measurements (κ=0.40-0.52). When the curves disagreed on whether an infant was <5th percentile for weight (8.3% of cohort) or length (13.6% of cohort), the WHO curve classified the infant in this category over 90% of the time. For head circumference, the IHDP curve classified more infants below the 5th percentile. Gestational age <30 weeks was associated with growth curve disagreement for weight and length <5th percentile.

CONCLUSION

Choice of growth curve affects the assessment of growth and the classification of underweight status. Longitudinal studies are needed to determine which assessment identifies the greatest number of premature infants at risk for long-term growth issues.

WHO growth chart awareness among clinicians in Kentucky

OBJECTIVES

To examine children's growth chart use among clinicians and explore awareness of the Centers for Disease Control and Prevention's (CDC) recommendations for the use of World Health Organization (WHO) growth charts.

METHODS

A cross-sectional survey of pediatricians and family practitioners in Kentucky.

RESULTS

Only 29% of clinicians reported using WHO growth charts, with board-certified urban pediatricians more likely to be aware of the WHO growth charts and to recognize that CDC growth charts led them to overdiagnose infants as being underweight. Approximately one-fourth of respondents did not know the source of growth charts for their practice. Only 13% of clinicians discussed body mass index and other vital parameters with parents and provided copies of growth charts at the end of patient visits. Clinicians who provided copies of growth charts to parents were more likely to be nonacademic, board-certified pediatricians in urban areas with more than 10 years' experience.

CONCLUSIONS

More than 6 months after the CDC's recommendation to use WHO growth charts for children younger than 2 years old, few clinicians were familiar with and used the WHO charts. Increased awareness and training, increased availability of WHO growth charts, and adherence to the recommendations will result in more accurate growth calculations and avoid underidentification of infants at risk for overweight and obesity.

Is overweight at 12 months associated with differences in eating behaviour or dietary intake among children selected for inappropriate bottle use?

Bottle feeding beyond the recommended weaning age of 12 months is a risk factor for childhood obesity. This paper describes a sample of toddlers at high risk for obesity: prolonged bottle users from a low-income multi-ethnic community. We report here baseline mealtime and feeding behaviour, 24 h dietary recall and bottle intake data for Feeding Young Children Study (FYCS) participants, by overweight (≥85% weight-for-length) status. FYCS enrolled 12-13-month-olds from urban nutrition programmes for low-income families in the United States who were consuming ≥2 bottles per day. Our sample was predominately Hispanic (62%), 44% of mothers were born outside of the United States and 48% were male. Overall, 35% were overweight. Overweight status was not associated with mealtime/feeding behaviours, bottle use or dietary intake. Most (90%) children ate enough, were easily satisfied and did not exhibit negative (e.g. crying, screaming) mealtime behaviours, per parent report. The sample's median consumption of 4 bottles per day accounted for 50% of their total calories; each bottle averaged 7 ounces and contained 120 calories. Mean daily energy intake, 1098.3 kcal day(-1) (standard deviation = 346.1), did not differ by weight status, nor did intake of fat, saturated fat, protein or carbohydrates. Whole milk intake, primarily consumed via bottles, did not differ by weight status. Thus, overweight 12-13-month-olds in FYCS were remarkably similar to their non-overweight peers in terms of several obesity risk factors. Findings lend support to the set-point theory and prior work finding that weight and intake patterns in the first year of life alter subsequent obesity risk.

Effects of bariatric surgery on adipokine-induced inflammation and insulin resistance

Over a third of the US population is obese and at high risk for developing type 2 diabetes, insulin resistance, and other metabolic disorders. Obesity is considered a chronic low-grade inflammatory condition that is primarily attributed to expansion and inflammation of adipose tissues. Indeed, adipocytes produce and secrete numerous proinflammatory and anti-inflammatory cytokines known as adipokines. When the balance of these adipokines is shifted toward higher production of proinflammatory factors, local inflammation within adipose tissues and subsequently systemic inflammation occur. These adipokines including leptin, visfatin, resistin, apelin, vaspin, and retinol binding protein-4 can regulate inflammatory responses and contribute to the pathogenesis of diabetes. These effects are mediated by key inflammatory signaling molecules including activated serine kinases such as c-Jun N-terminal kinase and serine kinases inhibitor κB kinase and insulin signaling molecules including insulin receptor substrates, protein kinase B (PKB, also known as Akt), and nuclear factor kappa B. Bariatric surgery can decrease body weight and improve insulin resistance in morbidly obese subjects. However, despite reports suggesting reduced inflammation and weight-independent effects of bariatric surgery on glucose metabolism, mechanisms behind such improvements are not yet well understood. This review article focuses on some of these novel adipokines and discusses their changes after bariatric surgery and their relationship to insulin resistance, fat mass, inflammation, and glucose homeostasis.

Performance of WHO growth standards on Indian children with growth related disorders

OBJECTIVE

To assess performance of WHO 2006 standards on anthropometric measurements of children referred for growth related disorders to a speciality pediatric clinic in Pune, India, from June 2006 through June 2010.

METHODS

Data presented in this study were collected retrospectively from case records of all children from birth to 60 mo (n=1840, mean age 2.7±1.3 y) who presented with growth related disorders; healthy age and sex matched children were recruited as controls (n=824, mean age 2.8±1.2 y). Children were divided as per their clinical diagnosis into eight different groups: growth hormone deficiency, bone disorders, syndromic short stature, familial short stature, hypothyroidism, nutritional and systemic disorder, other endocrinopathies and overgrowth disorders. Anthropometric parameters for all study subjects were converted to standard deviation scores (SD scores) using the WHO Anthro 2005.

RESULTS

Mean height SD scores of children with growth related disorders were significantly lower than that of the controls, while that of the tall children were significantly higher (p<0.05). All children who were clinically very short were below the 1st percentile, while none of the children with overgrowth or normal children were classified as stunted. Weight for height SD scores of children with nutritional and systemic disorders were the lowest, while those for the obese children were the highest.

CONCLUSIONS

The present results suggest that the WHO 2006 growth standards classify children with growth disorders appropriately and the classification is in concordance with the clinical assessment. They provide health practitioners in a clinical setting with an effective tool to assess growth of children.

Determinants of high weight gain and high BMI status in the first three months in urban Chinese infants

OBJECTIVES

Investigate the potential factors associated with high weight gain and high BMI status in the first three months of life.

METHODS

Totally, 930 healthy neonates (489 boys and 441 girls) were involved in this community-based, prospective study in China. Data on body weight and length were collected at birth, and the 1st and 3rd months. A self-administered questionnaire was used to collect data regarding social demography, gestational status, delivery, and the feeding patterns of children.

RESULTS

Prevalences of high BMI status (BMI = 85th p, re WHO BMI standards) increased over time in both sexes, reaching 24.5% and 12.0% for boys and girls, respectively. General linear mixed models indicate high BMI status at 3 months is significantly and inversely associated with breastfeeding, as a proportion of feeding occasions [OR 0.74 (95%CI: 0.56-0.98)] and positively with lower birth weight [OR 2.07 (95%CI: 1.23-3.49)]. High weight gain (=85th p, re WHO velocity standards) in the first 3 months is also significantly associated with breastfeeding [OR 0.76 (95%CI: 0.59-0.96)] and sex, with boys at a higher risk than girls [OR 1.44 (95%CI: 1.07-1.97)]. Living in an extended family is associated with both high weight gain and high BMI status, but with marginal statistical significance.

CONCLUSION

Analyses indicate an increasing trend of high BMI status in early infancy. Breastfeeding provides a protective effect for both high weight gain and high BMI status. The results concerning birth weight suggests a target for intervention.

Worldwide implementation of the WHO Child Growth Standards

OBJECTIVE

To describe the worldwide implementation of the WHO Child Growth Standards ('WHO standards').

DESIGN

A questionnaire on the adoption of the WHO standards was sent to health authorities. The questions concerned anthropometric indicators adopted, newly introduced indicators, age range, use of sex-specific charts, previously used references, classification system, activities undertaken to roll out the standards and reasons for non-adoption.

SETTING

Worldwide.

SUBJECTS

Two hundred and nineteen countries and territories.

RESULTS

By April 2011, 125 countries had adopted the WHO standards, another twenty-five were considering their adoption and thirty had not adopted them. Preference for local references was the main reason for non-adoption. Weight-for-age was adopted almost universally, followed by length/height-for-age (104 countries) and weight-for-length/height (eighty-eight countries). Several countries (thirty-six) reported newly introducing BMI-for-age. Most countries opted for sex-specific charts and the Z-score classification. Many redesigned their child health records and updated recommendations on infant feeding, immunization and other health messages. About two-thirds reported incorporating the standards into pre-service training. Other activities ranged from incorporating the standards into computerized information systems, to providing supplies of anthropometric equipment and mobilizing resources for the standards' roll-out.

CONCLUSIONS

Five years after their release, the WHO standards have been widely scrutinized and implemented. Countries have adopted and harmonized best practices in child growth assessment and established the breast-fed infant as the norm against which to assess compliance with children's right to achieve their full genetic growth potential.

Implications of the WHO Child Growth Standards in rural Honduras

Objective

The present study analysed the impact of using the 2006 WHO Child Growth Standards (‘the WHO standards’) compared with the 1977 National Center for Health Statistics (NCHS) international growth reference (‘the NCHS reference’) on the calculated prevalence of chronic malnutrition in children aged 6·0–59·9 months.

Design

Anthropometric data were collected as part of a cross-sectional study exploring the association between household environments and nutritional status of children. Z-scores were computed for height-for-age (HAZ), weight-for-age (WAZ) and weight-for-height (WHZ) using each reference/standard. Results were compared using Bland–Altman plots, percentage agreement, kappa statistics, line graphs and proportion of children in Z-score categories.

Setting

The study was conducted in thirteen rural villages within Honduras's department of Intibucá.

Subjects

Children aged 6·0–59·9 months were the focus of the analysis, and households with children in this age range served as the sampling unit for the study.

Results

The WHO standards yielded lower means for HAZ and higher means for WAZ and WHZ compared with the NCHS reference. The WHO standards and NCHS reference showed good agreement between Z-score categories, except for HAZ among males aged 24·0–35·9 months and WHZ among males aged >24·0 months. Using the WHO standards resulted in higher proportions of stunting (low HAZ) and overweight (high WHZ) and lower proportions of underweight (low WAZ). The degree of difference among these measures varied by age and gender.

Conclusions

The choice of growth reference/standard employed in nutritional surveys may have important methodological and policy implications. While ostensibly comparable, data on nutritional indicators derived with different growth references/standards must be interpreted cautiously.

Is home birth a marker for severe malnutrition in early infancy in urban communities of low-income countries?

This matched case-control study set out to determine the association between place of delivery and severe undernutrition in early infancy in a low-income country. All infants (aged 0-3 months) with severe undernutrition attending four well-child clinics for routine immunization in inner-city Lagos, Nigeria were matched for age and sex with well-nourished peers. The main outcome measures were the adjusted-matched-odds ratios from conditional logistic regression analysis of undernutrition based on z-scores below -3 for weight-for-age, height/length-for-age and body-mass-index-for-age using current World Health Organization's Multicentre Growth Reference (WHO-MGR). From an eligible population of 7075 mother-infant pairs, 918 severely undernourished infants were enlisted as cases matched with 1836 controls. While there was no statistically significant difference between infants born outside hospitals as a group compared to those born in hospitals, infants delivered at residential homes compared to public hospitals had two-to-three fold odds of being severely underweight (p=0.002), severely stunted (p < 0.001) and severely wasted (p=0.008) after controlling for potential confounders. Infants delivered in private hospitals were also significantly associated with severe stunting (p=0.032). This study demonstrates that delivery in homes and private hospitals are potential markers for severe undernutrition in early infancy in this urban population and merits closer attention in any early nutritional intervention in comparable settings of low-income countries.

Obesity in preschool children is more prevalent and identified at a younger age when WHO growth charts are used compared with CDC charts

Our objective was to compare the prevalence and determinants of child obesity using the WHO child growth standards compared with the CDC growth reference. We used data from 143,787 2- to 5-y olds who participated in the Massachusetts Special Supplemental Food and Nutrition Program for Women, Infants and Children (WIC) program between 2001 and 2006. The prevalence of obesity (>95th percentile, BMI-for-age) was 23.3% when we used the WHO standards vs. 16.9% using the CDC reference; for obesity plus overweight (>85th percentile), the prevalence was 42.2 vs. 33.8%, respectively. The difference between the prevalence estimates was greatest at 24-36 mo of age. Multivariate logistic regression analysis indicated that child obesity (based on the WHO standards) was more common in boys, Hispanics, children of less educated mothers, and those born to obese mothers. These results confirm that the prevalence of child obesity is higher according to the WHO standards and indicate that the WHO charts allow for a more timely detection of obesity in childhood.

Lifecourse childhood adiposity trajectories associated with adolescent insulin resistance

OBJECTIVE

In light of the obesity epidemic, we aimed to characterize novel childhood adiposity trajectories from birth to age 14 years and to determine their relation to adolescent insulin resistance.

RESEARCH DESIGN AND METHODS

A total of 1,197 Australian children with cardiovascular/metabolic profiling at age 14 years were studied serially from birth to age 14 years. Semiparametric mixture modeling was applied to anthropometric data over eight time points to generate adiposity trajectories of z scores (weight-for-height and BMI). Fasting insulin and homeostasis model assessment of insulin resistance (HOMA-IR) were compared at age 14 years between adiposity trajectories.

RESULTS

Seven adiposity trajectories were identified. Three (two rising and one chronic high adiposity) trajectories comprised 32% of the population and were associated with significantly higher fasting insulin and HOMA-IR compared with a reference trajectory group (with longitudinal adiposity z scores of approximately zero). There was a significant sex by trajectory group interaction (P < 0.001). Girls within a rising trajectory from low to moderate adiposity did not show increased insulin resistance. Maternal obesity, excessive weight gain during pregnancy, and gestational diabetes were more prevalent in the chronic high adiposity trajectory.

CONCLUSIONS

A range of childhood adiposity trajectories exist. The greatest insulin resistance at age 14 years is seen in those with increasing trajectories regardless of birth weight and in high birth weight infants whose adiposity remains high. Public health professionals should urgently target both excessive weight gain in early childhood across all birth weights and maternal obesity and excessive weight gain during pregnancy.

The prevalence of wasting in Czech infants: a comparison of the WHO child growth standards and the Czech growth references

The objective of this descriptive study was to evaluate the performance of the international World Health Organization (WHO) child growth standards in the Czech Republic and determine the prevalence of wasting among children using the 1991 Czech growth reference and the WHO growth standards. The study utilized the 2006 WHO Child Growth Standards and the 1991 Czech growth references. The WHO standards were based on a longitudinal study of 882 children aged 0-24 months and on cross-sectional studies of 6669 children aged 18-71 months. The 1991 Czech growth references were based on a cross-sectional survey including 90 910 children aged 0-18 years (34 164 were children aged < 5 years). The prevalence of wasting was significantly higher among Czech children when using the WHO growth standards compared with the Czech references. The prevalence of wasting among 0-5-month-old children was 15.5% among boys and 12.9% among girls compared with the expected 2.3% of the WHO standards. In the length category of 50 cm, 9.0% of boys and 9.9% of girls fell under the WHO wasting cut-off compared with the 3% from the Czech growth reference. The application of the WHO growth standards may results in a significant increase of Czech children classified in the category of wasting, especially among infants aged 0-5 months. The performance and potential impacts of the WHO growth standards should be evaluated further before their adoption in the Czech Republic and other countries with local growth references.

Genetic factors are important determinants of impaired growth after infant cardiac surgery

OBJECTIVES

We sought to estimate the prevalence and identify the predictors of impaired growth after infant cardiac surgery.

METHODS

We performed a secondary analysis of a prospective study of the role of apolipoprotein E gene polymorphisms on neurodevelopment in young children after infant cardiac surgery. Prevalence estimates for growth velocity were derived by using anthropometric measures (weight and head circumference) obtained at birth and at 4 years of age. Genetic evaluation was also performed. Growth measure z scores were calculated by using World Health Organization Child Growth Standards. Growth velocity was evaluated by using 2 different techniques: first by clustering the children into one of 3 growth velocity subgroups based on z scores (impaired growth, difference < -0.5 standard deviation; stable growth, difference of -0.5 to 0.5 standard deviation; and improving growth, difference > 0.5 SD) and second by using continuous difference scores. Statistical analyses were conducted with a combination of proportional odds models for the ordered categories and simple linear regression for the continuous outcomes.

RESULTS

Three hundred nineteen full-term subjects had complete anthropometric measures for weight and head circumference at birth and 4 years. The cohort was 56% male. Genetic examinations were available for 97% (309/319) of the cohort (normal, 74%; definite or suspected genetic abnormality, 26%). Frequency counts for weight categories were as follows: impaired growth, 37%; stable growth, 31%; and improving growth, 32%. Frequency counts for head circumference categories were as follows: impaired growth, 39%; stable growth, 28%; and improving growth, 33%. The presence of a definite or suspected genetic syndrome (P = .04) was found to be a predictor of impaired growth for weight but not for head circumference. When growth z scores were used as continuous outcomes, the apolipoprotein E epsilon2 allele was found to be predictive of lower z scores for both weight (P = .02) and head circumference (P = .03).

CONCLUSIONS

Impaired growth for both weight and head circumference is common (both >30%) in this cohort of children after infant cardiac surgery. Both the apolipoprotein E epsilon2 allele and the presence of a definite or suspected genetic syndrome were associated with impaired weight growth velocity. The apolipoprotein E epsilon2 allele was also associated with impaired growth velocity for head circumference. Persistent poor growth might have long-term implications for the health and development of children with congenital heart defects.

Overweight and obesity in infants and pre-school children in the European Union: a review of existing data

The objective of this study was to synthesize available information on prevalence and time trends of overweight and obesity in pre-school children in the European Union. Retrieval and analysis or re-analysis of existing data were carried out. Data sources include WHO databases, Medline and Google, contact with authors of published and unpublished documents. Data were analysed using the International Obesity Task Force reference and cut-offs, and the WHO standard. Data were available from 18/27 countries. Comparisons were problematic because of different definitions and methods of data collection and analysis. The reported prevalence of overweight plus obesity at 4 years ranges from 11.8% in Romania (2004) to 32.3% in Spain (1998-2000). Countries in the Mediterranean region and the British islands report higher rates than those in middle, northern and eastern Europe. Rates are generally higher in girls than in boys. With the possible exception of England, there was no obvious trend towards increasing prevalence in the past 20-30 years in the five countries with data. The use of the WHO standard with cut-offs at 1, 2 and 3 standard deviations yields lower rates and removes gender differences. Data on overweight and obesity in pre-school children are scarce; their interpretation is difficult. Standard methods of surveillance, and research and policies on prevention and treatment, are urgently needed.

Childhood obesity and survival after in-hospital pediatric cardiopulmonary resuscitation

OBJECTIVE

We hypothesized that childhood obesity would be associated with decreased likelihood of survival to hospital discharge after in-hospital, pediatric cardiopulmonary resuscitation (CPR).

METHODS

We reviewed 1477 consecutive, pediatric, CPR index events (defined as the first CPR event during a hospitalization in that facility for a patient <18 years of age) reported to the American Heart Association National Registry of Cardiopulmonary Resuscitation between January 2000 and July 2004. The primary outcome was survival to hospital discharge. A total of 1268 index subjects (86%) with complete registry data were included for analysis. Children were classified as obese (> or =95th weight-for-length percentile if <2 years of age or > or =95th BMI-for-age percentile if > or =2 years of age) or underweight (<5th weight-for-length percentile if <2 years of age or <5th BMI-for-age percentile if > or =2 years of age), with adjustment for gender.

RESULTS

Obesity was noted for 213 (17%) of 1268 subjects and underweight for 571 (45%) of 1268 subjects. Obesity was more likely to be associated with male gender, noncardiac medical illness, and cancer and inversely associated with heart failure. Underweight was more likely to be associated with male gender, cardiac surgery, and prematurity and inversely associated with age and cancer. Self-reported, process-of-care, CPR quality was generally worse for obese children. With adjustment for important potential confounding factors, obesity was independently associated with worse odds of event survival (adjusted odds ratio: 0.58 [95% confidence interval: 0.35-0.76]) and survival to hospital discharge (adjusted odds ratio: 0.62 [95% confidence interval: 0.38-0.93]) after in-hospital, pediatric CPR. Underweight was not associated with worse outcomes.

CONCLUSIONS

Childhood obesity is associated with a lower rate of survival to hospital discharge after in-hospital, pediatric CPR.

Undernutrition and obesity in indigenous children: epidemiology, prevention, and treatment

Over the past 50 years there has been a shift in nutritional problems amongst Indigenous children in developed countries from under-nutrition and growth faltering to overweight and obesity; the major exception is small numbers of Indigenous children predominately living in remote areas of Northern Australia. Nutritional problems reflect social disadvantage and occur with disproportionately high incidence in all disadvantaged subgroups. There is limited evidence of benefit from any strategies to prevent or treat undernutrition and obesity; there are a limited number of individual studies with generalizable high grade evidence of benefit. Potential solutions require a whole of society approach.