The stunting syndrome in developing countries

Social determinants of inequalities in child undernutrition in Bangladesh: A decomposition analysis

Socioeconomic inequalities in child undernutrition remain one of the main challenges in Bangladesh. The social determinants of health are mostly responsible for such inequalities across different population groups. However, no study has examined the relative contribution of different social determinants to the socioeconomic inequality in child undernutrition in Bangladesh. Our objective is to measure the extent of socioeconomic-related inequalities in childhood stunting and identify the key social determinants that potentially explain these inequalities in Bangladesh. We used data for children younger than 5 years of age for this analysis from 2 rounds of Bangladesh Demographic and Health Surveys conducted in 2004 and 2014. We examined the socioeconomic inequality in stunting using the concentration curve and concentration index. We then decomposed the concentration index into the contributions of individual social determinants. We found significant inequality in stunting prevalence. The negative concentration index of stunting indicated that stunting was more concentrated among the poor than among the well-off. Our results suggest that inequalities in stunting increased between 2004 and 2014. Household economic status, maternal and paternal education, health-seeking behavior of the mothers, sanitation, fertility, and maternal stature were the major contributors to the disparity in stunting prevalence in Bangladesh. Equity is a critical component of sustainable development goals. Health policymakers should work together across sectors and develop strategies for effective intersectoral actions to adequately address the social determinants of equity and reduce inequalities in stunting and other health outcomes.

Protein Malnutrition Modifies Innate Immunity and Gene Expression by Intestinal Epithelial Cells and Human Rotavirus Infection in Neonatal Gnotobiotic Pigs

Malnutrition and rotavirus infection, prevalent in developing countries, individually and in combination, affect the health of millions of children, compromising their immunity and increasing the rates of death from infectious diseases. However, the interactions between the two and their combined effects on immune and intestinal functions are poorly understood. We have established the first human infant microbiota-transplanted neonatal pig model of childhood malnutrition that reproduced the impaired immune, intestinal, and other physiological functions seen in malnourished children. This model can be used to evaluate relevant dietary and other health-promoting interventions. Our findings provide an explanation of why adequate nutrition alone may lack efficacy in malnourished children.

Malnutrition affects millions of children in developing countries, compromising immunity and contributing to increased rates of death from infectious diseases. Rotavirus is a major etiological agent of childhood diarrhea in developing countries, where malnutrition is prevalent. However, the interactions between the two and their combined effects on immune and intestinal functions are poorly understood. In this study, we used neonatal gnotobiotic (Gn) pigs transplanted with the fecal microbiota of a healthy 2-month-old infant (HIFM) and fed protein-deficient or -sufficient bovine milk diets. Protein deficiency induced hypoproteinemia, hypoalbuminemia, hypoglycemia, stunting, and generalized edema in Gn pigs, as observed in protein-malnourished children. Irrespective of the diet, human rotavirus (HRV) infection early, at HIFM posttransplantation day 3 (PTD3), resulted in adverse health effects and higher mortality rates (45 to 75%) than later HRV infection (PTD10). Protein malnutrition exacerbated HRV infection and affected the morphology and function of the small intestinal epithelial barrier. In pigs infected with HRV at PTD10, there was a uniform decrease in the function and/or frequencies of natural killer cells, plasmacytoid dendritic cells, and CD103⁺ and apoptotic mononuclear cells and altered gene expression profiles of intestinal epithelial cells (chromogranin A, mucin 2, proliferating cell nuclear antigen, SRY-Box 9, and villin). Thus, we have established the first HIFM-transplanted neonatal pig model that recapitulates major aspects of protein malnutrition in children and can be used to evaluate physiologically relevant interventions. Our findings provide an explanation of why nutrient-rich diets alone may lack efficacy in malnourished children.

IMPORTANCE Malnutrition and rotavirus infection, prevalent in developing countries, individually and in combination, affect the health of millions of children, compromising their immunity and increasing the rates of death from infectious diseases. However, the interactions between the two and their combined effects on immune and intestinal functions are poorly understood. We have established the first human infant microbiota-transplanted neonatal pig model of childhood malnutrition that reproduced the impaired immune, intestinal, and other physiological functions seen in malnourished children. This model can be used to evaluate relevant dietary and other health-promoting interventions. Our findings provide an explanation of why adequate nutrition alone may lack efficacy in malnourished children.

Predicting Undernutrition at Age 2 Years with Early Attained Weight and Length Compared with Weight and Length Velocity

OBJECTIVE

To estimate the abilities of weight and length velocities vs attained growth measures to predict stunting, wasting, and underweight at age 2 years.

STUDY DESIGN

We analyzed data from a community-based cohort study (The Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development study [MAL-ED] study) in Bhaktapur, Nepal. A total of 240 randomly selected children were enrolled at birth and followed up monthly up to age 24 months. Linear and logistic regression models were used to predict malnutrition at 2 years of age with growth velocity z scores at 0-3, 0-6, 3-6, 6-9, 6-12, and 9-12 months (using the World Health Organization Growth Standards) or attained growth at 0, 3, 6, and 12 months as predictors.

RESULTS

At age 2 years, 4% of the children were wasted, 13% underweight, and 21% stunted. Children who were malnourished at age 2 years had lower mean growth z scores already at birth and throughout the study period. Anthropometric indicators in infancy were significant predictors for growth at the age of 2 years during most periods and at most ages in infancy. Weight-for-age z score, length-for-age z score, and weight-for-length z score at age 12 months had excellent areas under the curve (91-95) to predict the value of the same indicator at age 24 months. Maximum area under the curve values for weight and length velocity were somewhat lower (70-84).

CONCLUSIONS

Growth measured at one time point in infancy was better correlated with undernutrition at age 2 years than growth velocity.

Growth recovery and faltering through early adolescence in low- and middle-income countries: Determinants and implications for cognitive development

Child chronic undernutrition, as measured by stunting, is prevalent in low- and middle-income countries and is among the major threats to child development. While stunting and its implications for cognitive development have been considered irreversible beyond early childhood there is a lack of consensus in the literature on this, as there is some evidence of recovery from stunting and that this recovery may be associated with improvements in cognition. Less is known however, about the drivers of growth recovery and the aspects of recovery linked to cognitive development. In this paper we investigate the factors associated with growth recovery and faltering through age 12 years and the implications of the incidence, timing, and persistence of post-infancy recovery from stunting for cognitive development using longitudinal data from Ethiopia, India, Peru, and Vietnam. We find that the factors most systematically associated with accelerated growth both before and after early childhood and across countries include mother's height, household living standards and shocks, community wages, food prices, and garbage collection. Our results suggest that post-infancy recovery from stunting is more likely to be systematically associated with higher achievement scores across countries when it is persistent and that associations between growth trajectories and cognitive achievement in middle childhood do not persist through early adolescence across countries. Overall, our findings indicate that growth after early childhood is responsive to changes in the household and community environments and that growth promotion after early childhood may yield improvements in child cognitive development.

•

Living standards and costs are key predictors of child growth through age 12 years.

•

Persistent post-infancy growth recovery is strongly associated with child cognition.

•

Growth after early childhood is responsive to changes in the environment.

•

Sustained post-infancy growth promotion may improve child cognition.

Early life risk exposure and stunting in urban South African 2-year old children

Stunting is a measure of overall nutritional status and is a major public health concern because of its association with child mortality and morbidity and later adult performance. This study examined the effects of pregnancy events, birth characteristics and infant risk exposure on stunting at age 2 years. The study, established in 1990 in Soweto, an urban South African township, included 1098 mother-infant pairs enroled in the Birth to Twenty Plus longitudinal birth cohort study. In total, 22% of children were stunted at age 2 years, with males at greater risk than females [24.8 v. 19.4%, odds ratio (OR)=1.38; 95% confidence interval (CI): 1.03, 1.83]. In unadjusted analysis, male sex, household socio-economic status (SES), overcrowding, maternal age, maternal education, single motherhood, ethnicity, birth weight, gestational age and duration of infant breastfeeding were all significantly associated with stunting. In multivariable analysis, higher birth weight was protective against stunting for both sexes. Higher maternal education was protective for females only (adjusted odds ratio (AOR)=0.35; 95% CI: 0.14, 0.87), whereas wealthier household SES protected males (AOR for richest SES group=0.39; 95% CI: 0.16, 0.92). In this and other similar settings, current stunting prevention efforts focussing on primarily providing targeted proximal interventions, such as food supplements, risk undermining the critical importance of addressing key distal determinants of stunting such as SES and maternal education.

Following the World Health Organization's Recommendation of Exclusive Breastfeeding to 6 Months of Age Does Not Impact the Growth of Rural Gambian Infants

BACKGROUND

The WHO recommends exclusive breastfeeding (EBF) for the first 6 mo of life.

OBJECTIVE

The objective of this study was to assess the benefit of EBF to age 6 mo on growth in a large sample of rural Gambian infants at high risk of undernutrition.

METHODS

Infants with growth monitoring from birth to 2 y of age (n = 756) from the ENID (Early Nutrition and Immune Development) trial were categorized as exclusively breastfed if only breast milk and no other liquids or foods were given. EBF status was entered into confounder-adjusted multilevel models to test associations with growth trajectories by using >11,000 weight-for-age (WAZ), length-for-age (LAZ), and weight-for-length (WLZ) z score observations.

RESULTS

Thirty-two percent of infants were exclusively breastfed to age 6 mo. The mean age of discontinuation of EBF was 5.2 mo, and growth faltering started at ∼3.5 mo of age. Some evidence for a difference in WAZ and WHZ was found between infants who were exclusively breastfed to age 6 mo (EBF-6) and those who were not (nEBF-6), at 6 and 12 mo of age, with EBF-6 children having a higher mean z score. The differences in z scores between the 2 groups were small in magnitude (at 6 mo of age: 0.147 WAZ; 95% CI: -0.001, 0.293 WAZ; 0.189 WHZ; 95% CI: 0.038, 0.341 WHZ). No evidence for a difference between EBF-6 and nEBF-6 infants was observed for LAZ at any time point (6, 12, and 24 mo of age). Furthermore, a higher mean WLZ at 3 mo of age was associated with a subsequent higher mean age at discontinuation of EBF, which implied reverse causality in this setting (coefficient: 0.060; 95% CI: 0.008, 0.120).

CONCLUSION

This study suggests that EBF to age 6 mo has limited benefit to the growth of rural Gambian infants. This trial was registered at http://www.isrctn.com as ISRCTN49285450.

Predicting growth of the healthy infant using a genome scale metabolic model

An estimated 165 million children globally have stunted growth, and extensive growth data are available. Genome scale metabolic models allow the simulation of molecular flux over each metabolic enzyme, and are well adapted to analyze biological systems. We used a human genome scale metabolic model to simulate the mechanisms of growth and integrate data about breast-milk intake and composition with the infant's biomass and energy expenditure of major organs. The model predicted daily metabolic fluxes from birth to age 6 months, and accurately reproduced standard growth curves and changes in body composition. The model corroborates the finding that essential amino and fatty acids do not limit growth, but that energy is the main growth limiting factor. Disruptions to the supply and demand of energy markedly affected the predicted growth, indicating that elevated energy expenditure may be detrimental. The model was used to simulate the metabolic effect of mineral deficiencies, and showed the greatest growth reduction for deficiencies in copper, iron, and magnesium ions which affect energy production through oxidative phosphorylation. The model and simulation method were integrated to a platform and shared with the research community. The growth model constitutes another step towards the complete representation of human metabolism, and may further help improve the understanding of the mechanisms underlying stunting.

Nutrition, infection and stunting: the roles of deficiencies of individual nutrients and foods, and of inflammation, as determinants of reduced linear growth of children

The regulation of linear growth by nutritional and inflammatory influences is examined in terms of growth-plate endochondral ossification, in order to better understand stunted growth in children. Linear growth is controlled by complex genetic, physiological, and nutrient-sensitive endocrine/paracrine/autocrine mediated molecular signalling mechanisms, possibly including sleep adequacy through its influence on growth hormone secretion. Inflammation, which accompanies most infections and environmental enteric dysfunction, inhibits endochondral ossification through the action of mediators including proinflammatory cytokines, the activin A-follistatin system, glucocorticoids and fibroblast growth factor 21 (FGF21). In animal models linear growth is particularly sensitive to dietary protein as well as Zn intake, which act through insulin, insulin-like growth factor-1 (IGF-1) and its binding proteins, triiodothyronine, amino acids and Zn2+ to stimulate growth-plate protein and proteoglycan synthesis and cell cycle progression, actions which are blocked by corticosteroids and inflammatory cytokines. Observational human studies indicate stunting to be associated with nutritionally poor, mainly plant-based diets. Intervention studies provide some support for deficiencies of energy, protein, Zn and iodine and for multiple micronutrient deficiencies, at least during pregnancy. Of the animal-source foods, only milk has been specifically and repeatedly shown to exert an important influence on linear growth in both undernourished and well-nourished children. However, inflammation, caused by infections, environmental enteric dysfunction, which may be widespread in the absence of clean water, adequate sanitation and hygiene (WASH), and endogenous inflammation associated with excess adiposity, in each case contributes to stunting, and may explain why nutritional interventions are often unsuccessful. Current interventions to reduce stunting are targeting WASH as well as nutrition.

Tenofovir exposure in utero and linear growth in HIV-exposed, uninfected infants

OBJECTIVE

Tenofovir (TDF) affects bone health and is widely used in pregnancy but data are limited on the effects of TDF exposure in utero. We examined the association between duration of in-utero TDF exposure and linear growth in HIV-exposed, uninfected (HEU) infants.

DESIGN

A prospective cohort of pregnant women initiating TDF-containing regimens at primary care services in Cape Town, South Africa, were enrolled and followed with their breastfeeding infants through 12 months postpartum.

METHODS

Length-for-age z scores (LAZ) were calculated from infant lengths reported at birth and measured at 6, 12, 24, 36 and 48 weeks, using Fenton and WHO standards. Linear mixed-effects models were used to examine the association between duration of TDF exposure and LAZ over time.

RESULTS

In 464 singleton mother-infant pairs (median CD4 at ART initiation, 346 cells/μl; viral load (VL), 4.0 log10 copies/ml), the median duration of in-utero TDF exposure was 16.7 weeks (interquartile range, IQR 11.0-22.0) with 31, 44 and 25% of infants exposed to less than 12, 12-22 and more than 22 weeks of TDF, respectively. Overall, 12% of children were stunted (LAZ < -2) at 48 weeks. Duration of exposure was not associated with LAZ: adjusted mean difference for more than 22 vs less than 12 weeks, -0.12 (95% CI -0.47 to 0.23); 12-22 vs less than 12 weeks, -0.06 (95% CI -0.35 to 0.24). Mean LAZ was 0.15 lower per log increase in maternal VL at ART initiation (95% CI -0.29 to -0.0001).

CONCLUSION

These data suggest no association between duration of TDF exposure in utero and early linear growth.

A Combined Intervention of Zinc, Multiple Micronutrients, and Albendazole Does Not Ameliorate Environmental Enteric Dysfunction or Stunting in Rural Malawian Children in a Double-Blind Randomized Controlled Trial

BACKGROUND

Environmental enteric dysfunction (EED) and linear growth stunting affect many rural agrarian children in the developing world and contribute to the persistently high rates of stunting that are observed worldwide. Effective interventions to consistently ameliorate EED are lacking.

OBJECTIVE

We tested whether a bundle of safe and affordable interventions would decrease EED and stunting over 12-24 wk in a cohort of rural Malawian children 12-35 mo old.

METHODS

This was a randomized, double-blind, placebo-controlled clinical trial in which the intervention group received a single dose of albendazole and 14 d of zinc at enrollment and after 20 wk. The intervention group also received a daily multiple micronutrient powder throughout the 24 wk of study. The primary outcomes were improvements in EED, as measured by the urinary lactulose-to-mannitol ratio (L:M ratio) from dual-sugar absorption testing, and linear growth. Urinary L:M ratios and anthropometric measurements were evaluated after 12 and 24 wk of intervention and compared with a placebo group that did not receive any of these interventions.

RESULTS

A total of 254 children were enrolled at a mean age of 24 mo; 55% were female. Their mean weight-for-age z score was -1.5, and their mean length-for-age z score was -0.9. After 12 and 24 wk of study, increases in the L:M ratio did not differ between the intervention group (0.071 and 0.088 units, respectively) and the placebo group (0.073 and 0.080 units, respectively) (P = 0.87 and 0.19, respectively). Relative changes in length and weight also did not differ significantly between groups at any time point.

CONCLUSION

The combined usage of albendazole, zinc, and a daily multiple micronutrient powder did not decrease EED or stunting in this population of agrarian children 12-35 mo old in rural Malawi. Alternative interventions to improve these diseases should be investigated. This trial was registered at clinicaltrials.gov as NCT02253095.

Birth interval and stunting in children under five years of age in Peru (1996-2014)

BACKGROUND

Examine the evolution of stunting in <5 years of age in Peru and its relationship with birth interval (BI), and associated factors from 1996 to 2014.

METHODS

Data were extracted from the National Demographic and Health Survey of Peru (DHS) for the years 1996, 2000, 2005, 2010 and 2014 on children <5 years of age for stunting (height / age ≤ 2DS). The main independent variable of interest was BI dichotomized by interval between date of last and penultimate birth (≤24 months vs. >24 months) and others sociodemographic variables. Crude and adjusted odds ratios with 95% confidence intervals were estimated in logistic regression for the effect of BI and other variables on stunting by each survey year.

RESULTS

Between 1996 and 2014, stunting declined in both BI groups: ≤24 months: 35.8% to 21.8%; >24 months: 29.5% to 14.3%. BI was associated with stunting after adjustment for other variables in each survey except 2005. Of the other factors, sex, birth order (fourth child or more), maternal education and poverty were independently associated with stunting in all survey years. Residence in rural areas and in Amazon forest and highland regions was associated with stunting 1996 and 2000. Maternal age was not independently associated with stunting.

CONCLUSIONS

While stunting showed a decreasing trend from 1996 to 2014, birth interval exceeding 24 months exerted a protective effect on stunting across the years surveyed. Poverty, low maternal education and high birth order were associated with stunting in all survey years.

Determinants of stunting in children under 5 years in Madagascar

Madagascar is among countries where the prevalence of stunting is dramatically high in under 5 years old children. This study investigated the determinants of child stunting based on the UNICEF framework on the causes of malnutrition. A cutoff at 24 months was used to separate the child population into two groups. By using the latest Demographic and Health Survey (2009), logistic regressions were performed to determine the variables associated with stunting. In 2009, 40.1% of the 1,863 children aged 0-23 months and 53.9% of the 2,911 children aged 24-59 months were stunted contributing to the 48.5% overall stunting prevalence in the sample. Girls were less likely to be stunted (adjusted odds ratio with confidence interval [AOR] = 0.69 [0.55-0.88] and 0.84 [0.72-0.97], p < 0.01) than boys; the risk of stunting increased with age. Regarding underlying predictors, increased maternal height was associated with lower odds of stunting in both age groups (AOR = 0.75 [0.68-0.83] and 0.69 [0.61-0.77], p < 0.001). Children living in households using iodized salt (>15 ppm) had lower risk of stunting in the younger group (AOR = 0.76 [0.61-0.94], p < 0.05). Children living in urban areas were less likely to be stunted in both age groups (AOR = 0.67 [0.51-0.88] and 0.73 [0.59-0.90] respectively, p < 0.01]. Region of residence was also a significant basic factor for stunting. This study contributes to the understanding of the determinants of child stunting in Madagascar. The results confirmed the need for specific interventions for each of the two age groups.

Socio-economic and demographic correlates of stunting among adolescents of Assam, North- east India

The prevalence of stunting (low height-for-age) is a key indicator of long-term chronic undernutrition which reflects an anthropometric failure to reach linear growth potentials due to prolonged food deprivation and/or disease or illness during the early stage of life. The present study assesses the prevalence and socio-economic and demographic correlates of stunting among adolescents of the North-east India. This cross-sectional study was undertaken among 1,818 (830 boys; 988 girls) adolescents (aged 10-18 years) belonging to ethnically heterogeneous populations of Karbi Anglong district of Assam, using stratified random sampling method. Anthropometric measurements of height and weight were recorded using standard procedures. Socio-economic and demographic variables were obtained using pre-structured schedule. The age-sex specific L, M and S reference values were used to calculate height-for-age Z-score (HAZ). According to WHO, HAZ found to be <−2SD was classified as stunting. The data were analysed using descriptive statistics, t-test, ANOVA, chi-square analyses, binary and step-wise multiple logistic regression analysis in SPSS (version, 17.0). The prevalence of stunting was observed to be significantly higher among boys (48.4%) than girls (37.8%) (p<0.01). Age-sex specific prevalence was found to be higher among boys than girls aged 14-18 years and contrary were observed among girls aged 10-14 years (p>0.05). The binary logistic regression analysis showed that several socio-economic and demographic variables were significantly associated with stunting (p<0.05). The step-wise multiple logistic regression analysis showed that sex (boys), age groups (13-15 years and 16-18 years), father’s occupation (cultivator) and Rupees ≤5000 household income was significantly associated with stunting (p<0.05). Appropriate nutritional intervention programmes and dissemination of knowledge at population level related to undernutrition are necessary to ameliorate their nutritional status.

Linear growth trajectories in Zimbabwean infants

BACKGROUND

Undernutrition in early life underlies 45% of child deaths globally. Stunting malnutrition (suboptimal linear growth) also has long-term negative effects on childhood development. Linear growth deficits accrue in the first 1000 d of life. Understanding the patterns and timing of linear growth faltering or recovery during this period is critical to inform interventions to improve infant nutritional status.

OBJECTIVE

We aimed to identify the pattern and determinants of linear growth trajectories from birth through 24 mo of age in a cohort of Zimbabwean infants.

DESIGN

We performed a secondary analysis of longitudinal data from a subset of 3338 HIV-unexposed infants in the Zimbabwe Vitamin A for Mothers and Babies trial. We used k-means clustering for longitudinal data to identify linear growth trajectories and multinomial logistic regression to identify covariates that were associated with each trajectory group.

RESULTS

For the entire population, the mean length-for-age z score declined from -0.6 to -1.4 between birth and 24 mo of age. Within the population, 4 growth patterns were identified that were each characterized by worsening linear growth restriction but varied in the timing and severity of growth declines. In our multivariable model, 1-U increments in maternal height and education and infant birth weight and length were associated with greater relative odds of membership in the least-growth restricted groups (A and B) and reduced odds of membership in the more-growth restricted groups (C and D). Male infant sex was associated with reduced odds of membership in groups A and B but with increased odds of membership in groups C and D.

CONCLUSION

In this population, all children were experiencing growth restriction but differences in magnitude were influenced by maternal height and education and infant sex, birth weight, and birth length, which suggest that key determinants of linear growth may already be established by the time of birth. This trial was registered at clinicaltrials.gov as NCT00198718.

Environmental Enteric Dysfunction and Growth Failure/Stunting in Global Child Health

Approximately 25% of the world's children aged <5 years have stunted growth, which is associated with increased mortality, cognitive dysfunction, and loss of productivity. Reducing by 40% the number of stunted children is a global target for 2030. The pathogenesis of stunting is poorly understood. Prenatal and postnatal nutritional deficits and enteric and systemic infections clearly contribute, but recent findings implicate a central role for environmental enteric dysfunction (EED), a generalized disturbance of small intestinal structure and function found at a high prevalence in children living under unsanitary conditions. Mechanisms contributing to growth failure in EED include intestinal leakiness and heightened permeability, gut inflammation, dysbiosis and bacterial translocation, systemic inflammation, and nutrient malabsorption. Because EED has multiple causal pathways, approaches to manage it need to be multifaceted. Potential interventions to tackle EED include: (1) reduction of exposure to feces and contact with animals through programs such as improved water, sanitation, and hygiene; (2) breastfeeding and enhanced dietary diversity; (3) probiotics and prebiotics; (4) nutrient supplements, including zinc, polyunsaturated fatty acids, and amino acids; (5) antiinflammatory agents such as 5-aminosalicyclic acid; and (6) antibiotics in the context of acute malnutrition and infection. Better understanding of the underlying causes of EED and development of noninvasive, practical, simple, and affordable point-of-care diagnostic tools remain key gaps. "Omics" technologies (genomics, epigenomics, transcriptomics, proteomics, and metabolomics) and stable isotope techniques (eg, ¹³C breath tests) targeted at children and their intestinal microbiota will enhance our ability to successfully identify, manage, and prevent this disorder.

Prevalence, Demographic Characteristics and Associated Risk Factors of Malnutrition Among 0-5 Aged Children: A Cross-Sectional Study From Van, Eastern Turkey

Malnutrition in childhood is a dramatic indicator of poor socio-economical status worldwide. To recognize and reveal the socio-demographic features is crucial, especially for developing countries. Our aim was to investigate the prevalence and association with sociodemographic variables of malnutrition in 0-5 years old children in Van, Turkey. A total of 702 children are included in this cross-sectional study. Demographic features of subject including age, gender, family characteristics and other data were obtained. Nutritional assessment was done using anthropometric indices including weight-for-age, height-for-age, weight-for-height, head circumference and body mass index-for-age. Multivariate logistic regressions were carried out to assess malnutrition-associated factors. Prevalence of underweight, stunting and wasting were 19.7, 17.7 and 16.2%, respectively. Socio-demographic variables that statistical significantly in association with malnutrition were low monthly family income, educational level and employment status of father, parental consanguinity, number of pregnancies, regular intake of vitamin D and history of prematurity. The prevalence of children with head circumference-z score ≤2SD and body mass index-for-age ≤2SD were 9.8 and 16.3%, respectively. Multivariate analysis detected following risk factors for these indices; low monthly family income, history of prematurity, unemployed father and the period between pregnancies (1-2 years). We found that prevalence of malnutrition in the city of Van, was still higher than more developed regions of Turkey. The associated risk factors of malnutrition should be specifically interpreted by health professionals and also by government authorities that are responsible for making practical politics of public health.

Trends and determinants of inequities in childhood stunting in Bangladesh from 1996/7 to 2014

BACKGROUND

We explore long-term trends and determinants of socioeconomic inequities in chronic childhood undernutrition measured by stunting among under-five children in Bangladesh. Given that one in three children remain stunted in Bangladesh, the socioeconomic mapping of stunting prevalence may be critical in designing public policies and interventions to eradicate childhood undernutrition.

METHODS

Six rounds of Bangladesh Demographic and Health Survey data are utilized, spanning the period 1996/97 to 2014. Using recognized measures of absolute and relative inequality (namely, absolute and relative difference, concentration curve and index), we quantify trends, and decompose changes in the concentration index to identify factors that best explain observed dynamics.

RESULTS

Despite remarkable improvements in average nutritional status over the last two decades, socio-economic inequalities have persisted, and according to some measures, even worsened. For example, expressed as rate-ratios, the relative inequality in under-five stunting increased by 56% and the concentration index more than doubled between 1996/97 and 2014. Decomposition analyses find that wealth and maternal factors such as mothers' schooling and short stature are major contributors to observed socio-economic inequalities in child undernutrition and their changes over time.

CONCLUSIONS

Reflecting on recent success around socioeconomic and gender equity in child mortality, and the weak legacy of nutrition policy in Bangladesh, we suggest that nutrition programming energies be focused specifically on the most disadvantaged and applied at scale to close socioeconomic gaps in stunting prevalence.

Stunting Mediates the Association between Small-for-Gestational-Age and Postneonatal Mortality

BACKGROUND

In sub-Saharan Africa, one-third of all births are small for gestational age (SGA), and 4.4 million children are stunted; both conditions increase the risk of child mortality. SGA has also been shown to increase the risk of stunting.

OBJECTIVE

We tested whether the association between SGA and postneonatal mortality is mediated by stunting.

METHODS

We used longitudinal data from children aged 6 wk to 24 mo (n = 12,155) enrolled in the ZVITAMBO (Zimbabwe Vitamin A for Mothers and Babies) trial. HIV exposure was defined based on maternal HIV status at baseline. SGA was defined as birthweight <10th percentile of the INTERGROWTH-21st (International Fetal and Newborn Growth Consortium for the 21st Century) standards. We used a standard mediation approach by comparing the attenuation of the risk when the mediator was added to the model. We used Cox proportional hazards models first to regress SGA on postneonatal mortality, controlling for age. Stunting (length-for-age z score <-2) was then included in the model to test mediation.

RESULTS

Approximately 20% of children were term SGA, and 23% were stunted before their last follow-up visit. In this cohort, 31% of children were exposed to HIV; the HIV-exposed group represented a pooled group of HIV-infected and HIV-exposed but uninfected children. Postneonatal mortality was significantly higher among children born SGA (HR: 1.5; 95% CI: 1.3, 1.7). This association was attenuated and not statistically significant when stunting was included in the model, suggesting a mediation effect (HR: 1.1; 95% CI: 0.91, 1.3). When stratified by HIV exposure status, we observed a significant attenuation of the risk, suggesting mediation, only among HIV-exposed children (model 1, HR: 1.3; 95% CI: 1.1, 1.6; model 2, HR: 1.1; 95% CI: 0.88, 1.3).

CONCLUSIONS

This analysis aids in investigating pathways that underlie an observed SGA-mortality relation and may inform survival interventions in undernourished settings.

Assessment of Environmental Enteric Dysfunction in the SHINE Trial: Methods and Challenges

Environmental enteric dysfunction (EED) is a virtually ubiquitous, but poorly defined, disorder of the small intestine among people living in conditions of poverty, which begins early in infancy and persists. EED is characterized by altered gut structure and function, leading to reduced absorptive surface area and impaired intestinal barrier function. It is hypothesized that recurrent exposure to fecal pathogens and changes in the composition of the intestinal microbiota initiate this process, which leads to a self-perpetuating cycle of pathology. We view EED as a primary gut disorder that drives chronic systemic inflammation, leading to growth hormone resistance and impaired linear growth. There is currently no accepted case definition or gold-standard biomarker of EED, making field studies challenging. The Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial in Zimbabwe is evaluating the independent and combined effects of a package of infant feeding and/or water, sanitation, and hygiene interventions on stunting and anemia. SHINE therefore provides an opportunity to longitudinally evaluate EED in a well-characterized cohort of infants, using a panel of biomarkers along the hypothesized causal pathway. Our aims are to describe the evolution of EED during infancy, ascertain its contribution to stunting, and investigate the impact of the randomized interventions on the EED pathway. In this article, we describe current concepts of EED, challenges in defining the condition, and our approach to evaluating EED in the SHINE trial.

Systematic review of evidence on the effectiveness of safe child faeces disposal interventions

OBJECTIVES

To review and synthesise the available evidence on the effectiveness of interventions targeting unsafe child faeces disposal in reducing this behaviour and improving child health in low- and middle-income countries.

METHODS

PubMed and EMBASE were systematically searched. Studies meeting the inclusion criteria were reviewed and key information on study methodologies and outcomes were extracted.

RESULTS

A total of 1048 articles were screened, and eight studies representing five countries were included for the review. Three were randomised controlled trials, and five were prospective cohort studies. There was wide variability across studies in the definition of 'safe disposal' of child faeces. Six studies reported the change in child faeces disposal practices associated with safe child faeces disposal interventions. However, only one study found a significant improvement in this behaviour. Two of the six studies that evaluated the health impact of delivered interventions found significant reductions in childhood diarrhoea associated with safe faeces disposal practices, and one study reported a positive effect on child growth and ascariasis. Only one study was identified that delivered a single intervention solely focused on safe child faeces disposal. Unfortunately, this study did not investigate the impact of this intervention on child health.

CONCLUSIONS

There are major methodological limitations in studies that assessed the impact of safe child faeces disposal interventions. The health impact of these interventions is inconclusive because the quality of the current evidence is poor. Randomised controlled trials are urgently needed to assess the impact of safe faeces disposal interventions on child health.

Growth and development in children born very low birthweight

OBJECTIVE

To examine the relationships between growth (birth to age 2 years) and developmental outcomes in children born with very low birthweight (VLBW).

DESIGN

Motor and mental development in children born with VLBW were regressed on anthropometric measurements at birth, 9 months and 2 years using multivariable regression.

SETTING

The Early Childhood Longitudinal Study-Birth Cohort, a longitudinal cohort, community sample, designed to be representative of children born across the USA.

PATIENTS

950 children born with VLBW (<1500 g).

MAIN OUTCOME MEASURES

Motor and cognitive scores on the Bayley Scales at 9 months and 24 months chronological age.

RESULTS

A high proportion of children exhibited poor growth, with length-for-age z-scores <-2 (ie, stunting) in 21.3% of children at 9 months (adjusted for prematurity) and 34.2% of children at 2 years. Compared with children having z-scores >-2, children with growth shortfalls in head circumference, length and weight had a higher adjusted OR (aOR) of low Bayley motor scores at 9 months and 2 years (aOR ranging from 1.8 to 3.3, all p<0.05), while low Bayley cognitive scores were predicted by 9-month deficits in length and weight (aOR 2.0 and 2.4, respectively, both p<0.01) and 2-year deficits in length and head circumference (aOR 2.9 and 2.8, both p<0.05).

CONCLUSION

Anthropometric measures of growth were linked to current and future neurodevelopmental outcomes in children born with VLBW. While careful length measures may be a particularly useful marker, deficits in all anthropometric measures were risk factors for developmental delays.

A mixed method study exploring adherence to and acceptability of small quantity lipid-based nutrient supplements (SQ-LNS) among pregnant and lactating women in Ghana and Malawi

BACKGROUND

Supplementing pregnant and lactating mothers with small quantity lipid-based nutrient supplements (SQ-LNS) has resulted in improvements in birth outcomes in some low-income settings. In order to be effective, SQ-LNS must be consumed regularly over sustained periods.

METHODS

The objective was to assess and compare acceptability of and adherence to SQ-LNS consumption among pregnant and lactating women in Ghana and Malawi throughout 12 months of supplementation. We enrolled women before 20 gestation weeks into randomized trials in Ghana (n = 1320) and Malawi (n = 869). In the SQ-LNS group participants received a 20 g sachet of supplement per day during pregnancy and the first 6 months of lactation. In the control groups participants received multiple micronutrients (MMN) during pregnancy and lactation or iron and folic acid (IFA) during pregnancy and calcium during lactation. We used questionnaires to collect data on self-reported adherence to daily use of supplements and conducted in-depth interviews with women in the SQ-LNS group to examine acceptability.

RESULTS

The mean self-reported adherence during the supplementation period was lower in Ghana (79.9 %) than in Malawi (91.7 %) for all supplements (difference 11.8 %, P < 0.001). Over time, adherence increased in Malawi but decreased in Ghana. In both countries, adherence in the SQ-LNS group was non-inferior to that in the control groups. Participants typically reported consuming SQ-LNS as instructed but when interviewers queried about experiences, most of the women described incidents of non-adherence. A usual reason for not consuming SQ-LNS was nausea and vomiting during pregnancy. Especially in Malawi, women reported sharing SQ-LNS with families and friends. Sustained use of SQ-LNS was attributed to expected health benefits and favorable sensory attributes. Often women compared their pregnancy to previous ones, and were of the view that SQ-LNS made a positive difference.

CONCLUSION

Self-reported sustained adherence to consume SQ-LNS daily was high in both sites but lower in Ghana than in Malawi. In Ghana, adherence decreased over time whereas in Malawi adherence increased. Acceptability and adherence appeared interlinked, complex and context-related. Sustained consumption of SQ-LNS may require tailoring interventions by context.

TRIAL REGISTRATION

The Ghana trial was registered at clinicaltrials.gov as NCT00970866 , and the Malawi trial as NCT01239693 .

New insights into environmental enteric dysfunction

Environmental enteric dysfunction (EED) has been recognised as an important contributing factor to physical and cognitive stunting, poor response to oral vaccines, limited resilience to acute infections and ultimately global childhood mortality. The aetiology of EED remains poorly defined but the epidemiology suggests a multifactorial combination of prenatal and early-life undernutrition and repeated infectious and/or toxic environmental insults due to unsanitary and unhygienic environments. Previous attempts at medical interventions to ameliorate EED have been unsatisfying. However, a new generation of imaging and '-omics' technologies hold promise for developing a new understanding of the pathophysiology of EED. A series of trials designed to decrease EED and stunting are taking novel approaches, including improvements in sanitation, hygiene and nutritional interventions. Although many challenges remain in defeating EED, the global child health community must redouble their efforts to reduce EED in order to make substantive improvements in morbidity and mortality worldwide.

An Exposome Perspective on Environmental Enteric Dysfunction

BACKGROUND

Environmental exposures to chemicals have been shown to influence gastrointestinal function, yet little is known regarding whether chemical mixtures may be involved in the development of a subclinical enteric dysfunction found in infants and children born into poor hygiene and sanitation. Advances in gastrointestinal and immunotoxicology fields merit inclusion in complex discussions of environmental enteric dysfunction (EED) that severely affects children in developing countries.

OBJECTIVE

We aimed to highlight exposome approaches for investigating the potential influence of environmental chemical exposures on EED development, including a role for toxicant modulation of gut immune system and microbiome function.

DISCUSSION

A major focus on fecal-oral contamination in impoverished living conditions already exists for EED, and should now expand to include environmental chemicals such as pesticides and heavy metals that may be anthropogenic or dietary or from microbial sources. A comprehensive characterization of environmental chemical exposures prenatally and occurring in infants and young children will enhance our knowledge of any associated risks for EED and stunting.

CONCLUSIONS

Integrating EED, chemical exposure, and stunting at various ages during childhood will enhance our apparent limited view when evaluating EED. Etiology and intervention studies should evaluate the suite of environmental chemical exposures as candidates in the composite of EED biomarkers.

CITATION

Mapesa JO, Maxwell AL, Ryan EP. 2016. An exposome perspective on environmental enteric dysfunction. Environ Health Perspect 124:1121-1126; http://dx.doi.org/10.1289/ehp.1510459.

Environmental predictors of stunting among children under-five in Somalia: cross-sectional studies from 2007 to 2010

BACKGROUND

Stunting among children under five years old is associated with long-term effects on cognitive development, school achievement, economic productivity in adulthood and maternal reproductive outcomes. Accurate estimation of stunting and tools to forecast risk are key to planning interventions. We estimated the prevalence and distribution of stunting among children under five years in Somalia from 2007 to 2010 and explored the role of environmental covariates in its forecasting.

METHODS

Data from household nutritional surveys in Somalia from 2007 to 2010 with a total of 1,066 clusters covering 73,778 children were included. We developed a Bayesian hierarchical space-time model to forecast stunting by using the relationship between observed stunting and environmental covariates in the preceding years. We then applied the model coefficients to environmental covariates in subsequent years. To determine the accuracy of the forecasting, we compared this model with a model that used data from all the years with the corresponding environmental covariates.

RESULTS

Rainfall (OR = 0.994, 95 % Credible interval (CrI): 0.993, 0.995) and vegetation cover (OR = 0.719, 95 % CrI: 0.603, 0.858) were significant in forecasting stunting. The difference in estimates of stunting using the two approaches was less than 3 % in all the regions for all forecast years.

CONCLUSION

Stunting in Somalia is spatially and temporally heterogeneous. Rainfall and vegetation are major drivers of these variations. The use of environmental covariates for forecasting of stunting is a potentially useful and affordable tool for planning interventions to reduce the high burden of malnutrition in Somalia.

Growth status of small for gestational age Indian children from two socioeconomic strata

AIMS

To assess growth and factors associated with growth in children born small for gestational age (SGA) from two socioeconomic strata in comparison to age- and sex-matched healthy controls.

METHODS

Retrospective study conducted at two hospitals in Pune, 0.5-5 years, 618 children: 189-SGA from upper socioeconomic strata (USS), 217-SGA from lower socioeconomic strata (LSS), and 212 appropriate for gestational age healthy controls were randomly selected. Birth and maternal history, socioeconomic status, length/height, and weight of children were recorded. Anthropometric data were converted to Z scores (height for age Z-score [HAZ], weight for age Z-score [WAZ]) using WHO AnthroPlus software.

RESULTS

The HAZ and WAZ of the SGA group were significantly lower as compared to the controls and that of the LSS SGAs were lower than USS SGAs (P < 0.05). Thirty two percent children were stunted (HAZ <-2.0) in USS and 49% in LSS (P < 0.05). Twenty nine percent children in the USS SGA group were stunted at 2 years and 17% at 5 years. In the LSS SGA group, 54% children were stunted at 2 years and 46% at 5 years. Generalized linear model revealed normal vaginal delivery (β = 0.625) and mother's age (β =0.072) were positively associated and high SES (β = -0.830), absence of major illness (β = -1.01), higher birth weight (β = -1.34) were negatively associated for risk of stunting (P < 0.05).

CONCLUSION

Children born SGA showed poor growth as compared to controls. Special attention to growth is necessary in children from LSS, very low birth weight babies, and those with major illnesses during early years of life.

Catch-up growth and growth deficits: Nine-year annual panel child growth for native Amazonians in Bolivia

BACKGROUND

Childhood growth stunting is negatively associated with cognitive and health outcomes, and is claimed to be irreversible after age 2.

AIM

To estimate growth rates for children aged 2-7 who were stunted (sex-age standardised z-score [HAZ] <-2), marginally-stunted (-2 ≤ HAZ ≤-1) or not-stunted (HAZ >-1) at baseline and tracked annually until age 11; frequency of movement among height categories; and variation in height predicted by early childhood height.

SUBJECTS AND METHODS

This study used a 9-year annual panel (2002-2010) from a native Amazonian society of horticulturalists-foragers (Tsimane'; n = 174 girls; 179 boys at baseline). Descriptive statistics and random-effect regressions were used.

RESULTS

This study found some evidence of catch-up growth in HAZ, but persistent height deficits. Children stunted at baseline improved 1 HAZ unit by age 11 and had higher annual growth rates than non-stunted children. Marginally-stunted boys had a 0.1 HAZ units higher annual growth rate than non-stunted boys. Despite some catch up, ∼ 80% of marginally-stunted children at baseline remained marginally-stunted by age 11. The height deficit increased from age 2 to 11. Modest year-to-year movement was found between height categories.

CONCLUSIONS

The prevalence of growth faltering among the Tsimane' has declined, but hurdles still substantially lock children into height categories.

Determinants and morbidities of multiple anthropometric deficits in southwest rural Ethiopia

OBJECTIVE

The aim of this study was to compare undernutrition with child morbidity and their determinants according to a composite index of anthropometrical failures and conventional indices.

METHODS

We used data generated from three rounds of a longitudinal panel survey conducted in nine districts in Oromiya Region and the Southern Nations, Nationality and Peoples Region of Ethiopia. We estimated undernutrition using conventional indices and composite index of anthropometrical failures. Included in this analysis were 579, 674, and 674 children age <5 y in rounds 1, 2, and 3, respectively. The households were recruited using the expanded program on immunization sampling method. The hierarchical nature of the data Applied nutritional investigation was taken into account during the statistical analysis using a two-level mixed-effects logistic regression model.

RESULTS

A composite index of anthropological failure, estimated 45.1%, 42.4%, and 46.4% of the children were undernourished in round 1, 2, and 3, respectively. The conventional indices estimated 24.4%, 24.2%, and 30.4% underweight in round 1, 2, and 3, respectively. Being female (odds ratio [OR], 7.4; 95% confidence interval [CI], 3.9-14.0); low dietary diversity (OR, 3.1; 95% CI, 1.6-5.9); medium dietary diversity (OR, 1.9; 95% CI, 1.1-3.3), and no special foods during illness (OR, 1.8; 95% CI, 1.2-2.8) were determinant of multiple anthropometrical failures. Children with multiple anthropometric failures were 2.6 times more likely to report child morbidities (OR, 2.6; 95% CI, 1.1-5.9). However, none of the conventional indices were associated with any of the reported child morbidities, such as stunting (OR, 1.1; 95% CI, 0.8-1.4), wasting (OR, 0.9; 95% CI, 0.5-1.6), or underweight (OR, 1.4; 95% CI, 1.0-2.0).

CONCLUSION

The conventional indices underestimated the prevalence of undernutrition by 20.7%. Children with multiple anthropometric failures are at high risk for developing child morbidities and should benefit from nutrition intervention to reduce child morbidities.

Immune Dysfunction as a Cause and Consequence of Malnutrition

Malnutrition, which encompasses under- and overnutrition, is responsible for an enormous morbidity and mortality burden globally. Malnutrition results from disordered nutrient assimilation but is also characterized by recurrent infections and chronic inflammation, implying an underlying immune defect. Defects emerge before birth via modifications in the immunoepigenome of malnourished parents, and these may contribute to intergenerational cycles of malnutrition. This review summarizes key recent studies from experimental animals, in vitro models, and human cohorts, and proposes that immune dysfunction is both a cause and a consequence of malnutrition. Focusing on childhood undernutrition, we highlight gaps in current understanding of immune dysfunction in malnutrition, with a view to therapeutically targeting immune pathways as a novel means to reduce morbidity and mortality.

Undernourished children principally die of common infections, and immune defects are consistently demonstrated in under- and overnutrition.

Parental malnutrition leads to epigenetic modifications of infant immune and metabolic genes.

Healthy gut development relies on sensing of dietary nutrients, commensal, and pathogenic microbes via immune receptors.

Recurrent infections, chronic inflammation, and enteropathy compound clinical malnutrition by altering gut structure and function.

Immune cell activation and systemic proinflammatory mediator levels are increased in malnutrition.

Malnutrition impairs immune priming by DC and monocytes, and impairs effector memory T cell function.

Immune dysfunction can directly drive pathological processes in malnutrition, including malabsorption, increased metabolic demand, dysregulation of the growth hormone and HPA axes, and greater susceptibility to infection.

Non-specific Effects of Vaccines and Stunting: Timing May Be Essential

Background

Bacillus Calmette-Guérin (BCG) vaccination possesses effects on health beyond its target disease, the so called “non-specific effects”. We evaluate these effects, as well as the effect of timing of BCG and other vaccinations, on stunting in Sub-Saharan African (SSA) children under five.

Methods

We use a Big Data design, including cross-sectional data for 368,450 children from 33 SSA countries. Logistic regression analysis is used with control factors at child, mother, household and context level.

Results

Overall, BCG vaccination did not affect stunting in SSA children (OR 1.00 [0.98–1.03]). Timing of BCG vaccination was of importance (β_time = 0.067 [0.061–0.073]): compared to unvaccinated children, BCG was associated with lower odds on stunting for children vaccinated early in life (OR 0.92 [0.89–0.94]) and higher odds for children vaccinated later in infancy (OR 1.64 [1.53–1.76]). Similar findings were done for diphtheria-tetanus-pertussis (DTP)1 and measles vaccination, and when hemoglobin concentration was used as outcome variable.

Conclusions

We found a general time-dependent pattern of non-specific effects of vaccination, with positive associations for vaccinations given early in life and negative associations for vaccinations given later in infancy. If confirmed in further research, our findings may provide a new perspective on the non-specific effects of vaccination.

•

BCG was associated with lower odds on stunting when given early in life and with higher odds when given later in infancy.

•

Similar associations were found for DTP1 and measles vaccination and with hemoglobin concentration as outcome.

•

Time-dependency of non-specific effects provides a new perspective in the field although confirmation is required.

Vaccines possess effects on health beyond their target disease, so called “non-specific effects”. Our results suggest that timing of vaccination may be important for these effects. In African children, BCG vaccination was associated with lower odds on stunting when given in the first month of life and higher odds on stunting when given later in infancy. Comparable time patterns were found for DTP1 and measles vaccination and with hemoglobin concentration as outcome. Findings were made possible by a Big Data design, using data on 368,450 African children that varied considerably in vaccination times and background characteristics. These results, if confirmed in further research, may provide a fundamental new perspective on the non-specific effects of vaccines.

Childhood stunting and the metabolic syndrome components in young adults from a Brazilian birth cohort study

BACKGROUND/OBJECTIVES

The aim of this study was to investigate the association between stunting in the second year of life and metabolic syndrome components in early adulthood among subjects who have been prospectively followed-up since birth, in a city in Southern Brazil.

SUBJECTS/METHODS

In 1984, we attempted to follow-up the entire cohort; the subjects were examined and their mothers interviewed. Stunting was defined by a length-for-age Z-score 2 s.d. or more below the mean, in accordance with the World Health Organization reference. Between 2004 and 2005, we again tried to follow the entire cohort; during this period the subjects were evaluated for the following metabolic syndrome components: high-density lipoprotein (HDL) cholesterol, triglycerides, random blood glucose, waist circumference and systolic and diastolic blood pressure. Family income at the time of the baby's birth, asset index, mother's education, mother's smoking during pregnancy and duration of breastfeeding were considered possible confounders. Linear regression was used in the unadjusted and adjusted analyses.

RESULTS

Among men, stunting was inversely associated with triglycerides (β=-11.90, confidence interval (CI)=-22.33 to -1.48) and waist circumference (β=-4.29, CI=-5.62 to -2.97), whereas for women stunting was negatively related to HDL-cholesterol (β=-4.50, CI=-6.47 to -2.52), triglycerides (β=-9.61, CI=-17.66 to -1.56) and waist circumference (β=-1.14, CI=-4.22 to -1.02). However, after controlling for confounding variables, these associations vanished.

CONCLUSIONS

The findings suggest that stunting in childhood is not associated with metabolic syndrome components in young adults.

Childhood stunting: a global perspective

Childhood stunting is the best overall indicator of children's well-being and an accurate reflection of social inequalities. Stunting is the most prevalent form of child malnutrition with an estimated 161 million children worldwide in 2013 falling below -2 SD from the length-for-age/height-for-age World Health Organization Child Growth Standards median. Many more millions suffer from some degree of growth faltering as the entire length-for-age/height-for-age z-score distribution is shifted to the left indicating that all children, and not only those falling below a specific cutoff, are affected. Despite global consensus on how to define and measure it, stunting often goes unrecognized in communities where short stature is the norm as linear growth is not routinely assessed in primary health care settings and it is difficult to visually recognize it. Growth faltering often begins in utero and continues for at least the first 2 years of post-natal life. Linear growth failure serves as a marker of multiple pathological disorders associated with increased morbidity and mortality, loss of physical growth potential, reduced neurodevelopmental and cognitive function and an elevated risk of chronic disease in adulthood. The severe irreversible physical and neurocognitive damage that accompanies stunted growth poses a major threat to human development. Increased awareness of stunting's magnitude and devastating consequences has resulted in its being identified as a major global health priority and the focus of international attention at the highest levels with global targets set for 2025 and beyond. The challenge is to prevent linear growth failure while keeping child overweight and obesity at bay.

Stunting correlates with high salivary and serum antibody levels after 13-valent pneumococcal conjugate vaccination of Venezuelan Amerindian children

OBJECTIVE

To determine the impact of pre-vaccination nutritional status on vaccine responses in Venezuelan Warao Amerindian children vaccinated with the 13-valent pneumococcal conjugate vaccine (PCV13) and to investigate whether saliva can be used as read-out for these vaccine responses.

METHODS

A cross-sectional cohort of 504 Venezuelan Warao children aged 6 weeks - 59 months residing in nine geographically isolated Warao communities were vaccinated with a primary series of PCV13 according to Centers for Disease Control and Prevention (CDC)-recommended age-related schedules. Post-vaccination antibody concentrations in serum and saliva of 411 children were measured by multiplex immunoassay. The influence of malnutrition present upon vaccination on post-vaccination antibody levels was assessed by univariate and multivariable generalized estimating equations linear regression analysis.

RESULTS

In both stunted (38%) and non-stunted (62%) children, salivary antibody concentrations correlated well with serum levels for all serotypes with coefficients varying from 0.61 for serotype 3-0.80 for serotypes 5, 6A and 23F (all p < 0.01). Surprisingly, higher serum and salivary antibody levels were observed with increasing levels of stunting in children for all serotypes. This was statistically significant for 5/13 and 11/13 serotype-specific serum and saliva IgG concentrations respectively.

CONCLUSION

Stunted Amerindian children showed generally higher antibody concentrations than well-nourished children following PCV13 vaccination, indicating that chronic malnutrition influences vaccine response. Saliva samples might be useful to monitor serotype-specific antibody levels induced by PCV vaccination. This would greatly facilitate studies of vaccine efficacy in rural settings, since participant resistance generally hampers blood drawing.

Conditional cash transfers and the double burden of malnutrition among children in Colombia: a quasi-experimental study

Conditional cash-transfer (CCT) programmes have been shown to improve the nutritional and health status of children from poor families. However, CCT programmes may have unintended and not fully known consequences by increasing the risk of overweight and obesity. We examined the impact of Familias en Acción (FA), a large CCT programme in Colombia, on the double burden of malnutrition among pre-school and school-aged children. Height and weight were measured before programme enrolment and during follow-ups in 1290 children from thirty-one treatment municipalities, being compared with 1584 children from sixty-two matched control municipalities. We used a difference-in-differences approach to evaluate the effect of FA on children’s stunting, BMI z-scores, thinness, overweight and obesity, controlling for individual and municipality-level confounders. At baseline, the prevalences of stunting and overweight were 30·3 and 15·4 %, respectively, in treatment municipalities and 27·9 and 17·4 % in control municipalities. FA was associated with reduced odds of thinness (OR 0·26; 95 % CI 0·09, 0·75) and higher BMI-for-age z-scores (BMI z-scores) (β 0·14; 95 % CI 0·00, 0·27; P<0·05), although the latter was of small clinical significance. The prevalence of stunting, overweight and obesity decreased over time, but the effect of FA on these outcomes was not significant. The CCT programme in Colombia reduced the odds of thinness, but had no effect on stunting, a more prevalent outcome. The FA programme had no effect on overweight or obesity, although BMI z-scores were higher for children under treatment, raising the possibility of an increase of small clinical significance on BMI among pre-school and school-aged children.

It's in the Milk: Feeding the Microbiome to Promote Infant Growth

Malnutrition is a global health burden affecting the development of millions of children worldwide, but the effects of current treatment strategies are modest. Charbonneau et al. (2016) identify sialylated oligosaccharides in breast milk as microbiota-dependent growth-promoting metabolites, paving the way for a new rational treatment of severe infant stunting.

Strengthening health services to deliver nutrition education to promote complementary feeding and healthy growth of infants and young children: formative research for a successful intervention in peri-urban Trujillo, Peru

Formative research is critical for developing effective nutrition-specific interventions to improve infant and young child (IYC) feeding practices and promote healthy growth. Health workers interact with caregivers during health facility visits, yet there is limited research about how to optimize delivery of such interventions during these visits. The extensive reach of IYC health services globally calls for research to address this gap. In Trujillo, Peru, formative research was conducted to explore complementary feeding practices with caregivers as well as health worker routines and interactions with caregivers related to feeding and healthy growth; results informed the development and delivery of an educational intervention. Multiple qualitative methods were used to collect data on a purposive sample of health workers and caregivers from three health facilities and communities: household trials followed. Complementary feeding messages with doable behaviours were developed, and three were selected as key to promote based on their nutritional impact and cultural acceptability. In the health facilities, medical consultation, well-child visits and nutrition consultation all dealt with aspects of IYC nutrition/growth during their interactions with caregivers but were independent and inconsistent in approach. A nutrition education strategy was developed based on consistency, quality and coverage in the IYC health services. We conclude that formative research undertaken in the community and IYC health services was critical to developing a successful and culturally relevant intervention to promote optimal complementary feeding practices and healthy growth during interactions between health workers and caregivers at routine health facility visits. © 2016 John Wiley & Sons Ltd.

Adult height, nutrition, and population health

In this review, the potential causes and consequences of adult height, a measure of cumulative net nutrition, in modern populations are summarized. The mechanisms linking adult height and health are examined, with a focus on the role of potential confounders. Evidence across studies indicates that short adult height (reflecting growth retardation) in low- and middle-income countries is driven by environmental conditions, especially net nutrition during early years. Some of the associations of height with health and social outcomes potentially reflect the association between these environmental factors and such outcomes. These conditions are manifested in the substantial differences in adult height that exist between and within countries and over time. This review suggests that adult height is a useful marker of variation in cumulative net nutrition, biological deprivation, and standard of living between and within populations and should be routinely measured. Linkages between adult height and health, within and across generations, suggest that adult height may be a potential tool for monitoring health conditions and that programs focused on offspring outcomes may consider maternal height as a potentially important influence.

Alpha-Melanocyte-Stimulating Hormone and Agouti-Related Protein: Do They Play a Role in Appetite Regulation in Childhood Obesity?

OBJECTIVE

The hypothalamus plays a crucial role in the regulation of feeding behavior. The anorexigenic neuropeptide alpha-melanocyte-stimulating hormone (α-MSH) and the orexigenic neuropeptide agouti-related protein (AgRP) are among the major peptides produced in the hypothalamus. This study investigated the plasma concentrations of α-MSH and AgRP in underweight and obese children and their healthy peers. The associations between α-MSH and AgRP levels and anthropometric and nutritional markers of malnutrition and obesity were also assessed.

METHODS

Healthy sex-matched subjects aged 2 to 12 years were divided into 3 groups, as underweight (n=57), obese (n=61), and of normal weight (n=57). Plasma fasting concentrations of α-MSH and AgRP were measured by enzyme-linked immunosorbent assay. The differences between the three groups as to the relationships between plasma concentrations of α-MSH and AgRP and anthropometric data, serum biochemical parameters and homeostatic model assessment of insulin resistance were evaluated.

RESULTS

Obese children had significantly lower α-MSH levels than underweight (1194±865 vs. 1904±1312 ng/mL, p=0.006) and normal weight (1194±865 vs. 1762±1463 ng/mL, p=0.036) children; there were no significant differences in the α-MSH levels between the underweight and normal weight children (p=0.811). Also, no significant differences were observed between the underweight and obese children regarding the AgRP levels (742±352 vs. 828±417 ng/mL, p=0.125). We found a significant positive correlation between plasma α-MSH and AgRP levels across the entire sample.

CONCLUSION

This study is the first to demonstrate body weight-related differences in α-MSH and AgRP levels in children. Circulating plasma α-MSH levels in obese children were markedly lower than those of underweight and normal-weight children. This suggests that α-MSH could play a role in appetite regulation.

Impact of Universal Health Coverage on Child Growth and Nutrition in Argentina

OBJECTIVES

To estimate trends of undernutrition (stunting and underweight) among children younger than 5 years covered by the universal health coverage programs Plan Nacer and Programa Sumar.

METHODS

From 2005 to 2013, Plan Nacer and Programa Sumar collected high-quality information on birth and visit dates, age (in days), gender, weight (in kg), and height (in cm) for 1.4 million children in 6386 health centers (13 million records) with broad coverage of vulnerable populations in Argentina.

RESULTS

The prevalence of stunting and underweight decreased 45.0% (from 20.6% to 11.3%) and 38.0% (from 4.0% to 2.5%), respectively, with differences between rural versus urban areas, gender, regions, age, and seasons.

CONCLUSIONS

Undernutrition prevalence substantially decreased in 2 programs in Argentina as a result of universal health coverage.

Gut microbiota in Malawian infants in a nutritional supplementation trial

OBJECTIVES

To examine whether two forms of lipid-based nutrient supplements (LNS) or a micronutrient-fortified corn-soya blend were associated with development of the gut microbiota in Malawian infants, to assess the microbiota profiles at the age of 6 and 18 months and to follow the changes during the 12-month period.

METHODS

This was a substudy of a 4-arm randomised controlled trial conducted in rural Malawi. Infants at the age of 6 months were randomised to receive no supplement during the primary follow-up period (control), 54 g/day of micronutrient-fortified LNS with milk protein base (milk LNS), 54 g/day of micronutrient-fortified LNS with soya protein base (soya LNS), or 71 g/day of micronutrient-fortified corn-soya blend for 12 months. Stool samples were collected at baseline (6 months) and end of trial (18 months). The 16S rRNA gene was amplified and subjected to multiplex sequencing.

RESULTS

A total of 213 infants had paired microbiota data at 6 and 18 months of age. The Dirichlet-multinomial test showed no significant difference in microbiota profile between the four intervention groups at either age (each P > 0.10). Bifidobacterium longum was most abundant at both ages. Lactobacillus ruminis, Shigella and Salmonella were present. The abundance of Prevotella and Faecalibacterium increased with age (each P < 0.001), while Bifidobacteriaceae and Enterobacteriaceae exhibited significant decrease (each P < 0.001).

CONCLUSIONS

Nutritional supplementation by LNS or corn-soya blend for twelve months did not affect the gut microbiota profile in the rural Malawian context.

Malnutrition and vaccination in developing countries

Malnutrition contributes to an estimated 45% of deaths among children under 5 years of age in developing countries, predominantly due to infections. Malnourished children therefore stand to benefit hugely from vaccination, but malnutrition has been described as the most common immunodeficiency globally, suggesting that they may not be able to respond effectively to vaccines. The immunology of malnutrition remains poorly characterized, but is associated with impairments in mucosal barrier integrity, and innate and adaptive immune dysfunction. Despite this, the majority of malnourished children can mount a protective immune response following vaccination, although the timing, quality and duration of responses may be impaired. This paper reviews the evidence for vaccine immunogenicity in malnourished children, discusses the importance of vaccination in prevention of malnutrition and highlights evidence gaps in our current knowledge.

The Potential Role of Mycotoxins as a Contributor to Stunting in the SHINE Trial

Children in developing countries experience multiple exposures that are harmful to their growth and development. An emerging concern is frequent exposure to mycotoxins that contaminate a wide range of staple foods, including maize and groundnuts. Three mycotoxins are suspected to contribute to poor child health and development: aflatoxin, fumonisin, and deoxynivalenol. We summarize the evidence that mycotoxin exposure is associated with stunting, and propose that the causal pathway may be through environmental enteric dysfunction (EED) and disturbance of the insulin-like growth factor 1 (IGF-1) axis. The objectives of this substudy are to assess the relationship between agricultural and harvest practices and mycotoxin exposure; to evaluate associations between mycotoxin exposure and child stunting; and to investigate EED as a potential pathway linking mycotoxin exposure to child stunting, to inform potential areas for intervention.

Preventing environmental enteric dysfunction through improved water, sanitation and hygiene: an opportunity for stunting reduction in developing countries

In 2011, one in every four (26%) children under 5 years of age worldwide was stunted. The realization that most stunting cannot be explained by poor diet or by diarrhoea, nor completely reversed by optimized diet and reduced diarrhoea has led to the hypothesis that a primary underlying cause of stunting is subclinical gut disease. Essentially, ingested microbes set in motion two overlapping and interacting pathways that result in linear growth impairment. Firstly, partial villous atrophy results in a reduced absorptive surface area and loss of digestive enzymes. This in turn results in maldigestion and malabsorption of much needed nutrients. Secondly, microbes and their products make the gut leaky, allowing luminal contents to translocate into systemic circulation. This creates a condition of chronic immune activation, which (i) diverts nutrient resources towards the metabolically expensive business of infection fighting rather than growth; (ii) suppresses the growth hormone‐IGF axis and inhibits bone growth, leading to growth impairment; and (iii) causes further damage to the intestinal mucosa thereby exacerbating the problem. As such, the unhygienic environments in which infants and young children live and grow must contribute to, if not be the overriding cause of, this environmental enteric dysfunction. We suggest that a package of baby‐WASH interventions (sanitation and water improvement, handwashing with soap, ensuring a clean play and infant feeding environment and food hygiene) that interrupt specific pathways through which feco‐oral transmission occurs in the first two years of a child's life may be central to global stunting reduction efforts.