Linear growth and child development in low- and middle-income countries: a meta-analysis

Drivers of Under-Five Stunting Trend in 14 Low- and Middle-Income Countries since the Turn of the Millennium: A Multilevel Pooled Analysis of 50 Demographic and Health Surveys

BACKGROUND

Understanding the drivers contributing to the decreasing trend in stunting is paramount to meeting the World Health Assembly's global target of 40% stunting reduction by 2025.

METHODS

We pooled data from 50 Demographic and Health Surveys since 2000 in 14 countries to examine the relationships between the stunting trend and potential factors at distal, intermediate, and proximal levels. A multilevel pooled trend analysis was used to estimate the association between the change in potential drivers at a country level and stunting probability for an individual child while adjusting for time trends and child-level covariates. A four-level mixed-effects linear probability regression model was fitted, accounting for the clustering of data by sampling clusters, survey-rounds, and countries.

RESULTS

Stunting followed a decreasing trend in all countries at an average annual rate of 1.04 percentage points. Among the distal factors assessed, a decrease in the Gini coefficient, an improvement in women's decision-making, and an increase in urbanization were significantly associated with a lower probability of stunting within a country. Improvements in households' access to improved sanitation facilities and drinking water sources, and children's access to basic vaccinations were the important intermediate service-related drivers, whereas improvements in early initiation of breastfeeding and a decrease in the prevalence of low birthweight were the important proximal drivers.

CONCLUSIONS

The results reinforce the need for a combination of nutrition-sensitive and -specific interventions to tackle the problem of stunting. The identified drivers help to guide global efforts to further accelerate stunting reduction and monitor progress against chronic childhood undernutrition.

Early life risk factors of motor, cognitive and language development: a pooled analysis of studies from low/middle-income countries

OBJECTIVE

To determine the magnitude of relationships of early life factors with child development in low/middle-income countries (LMICs).

DESIGN

Meta-analyses of standardised mean differences (SMDs) estimated from published and unpublished data.

DATA SOURCES

We searched Medline, bibliographies of key articles and reviews, and grey literature to identify studies from LMICs that collected data on early life exposures and child development. The most recent search was done on 4 November 2014. We then invited the first authors of the publications and investigators of unpublished studies to participate in the study.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies that assessed at least one domain of child development in at least 100 children under 7 years of age and collected at least one early life factor of interest were included in the study.

ANALYSES

Linear regression models were used to assess SMDs in child development by parental and child factors within each study. We then produced pooled estimates across studies using random effects meta-analyses.

RESULTS

We retrieved data from 21 studies including 20 882 children across 13 LMICs, to assess the associations of exposure to 14 major risk factors with child development. Children of mothers with secondary schooling had 0.14 SD (95% CI 0.05 to 0.25) higher cognitive scores compared with children whose mothers had primary education. Preterm birth was associated with 0.14 SD (-0.24 to -0.05) and 0.23 SD (-0.42 to -0.03) reductions in cognitive and motor scores, respectively. Maternal short stature, anaemia in infancy and lack of access to clean water and sanitation had significant negative associations with cognitive and motor development with effects ranging from -0.18 to -0.10 SDs.

CONCLUSIONS

Differential parental, environmental and nutritional factors contribute to disparities in child development across LMICs. Targeting these factors from prepregnancy through childhood may improve health and development of children.

Stunting trajectories from post-infancy to adolescence in Ethiopia, India, Peru, and Vietnam

Many interventions focus on preventing stunting in the first 1,000 days of life. We take a broader perspective on childhood growth to assess the proportions of children who suffer persistent stunting, recover, and falter and become newly stunted between birth and adolescence. We use longitudinal data collected on 7,128 children in Ethiopia, India, Peru, and Vietnam. Data were collected in five survey waves between the ages of 1 to 15 years. We use descriptive and graphical approaches to compare the trajectories of children first stunted by age 1, first stunted by age 5, and those remained not stunted until age 5. On average, 29.6% of children were first stunted by age 1, 12.9% of children were first stunted by the age 5, and 68.7% of children were not stunted at either age 1 or age 5. A larger percentage of children stunted by age 1 remained stunted at age 15 (40.7%) compared with those who were first stunted by age 5 (32.3%); 33.7% of children first stunted by age 1 and 31.1% of children first stunted by age 5 go on to recover, but then falter during later childhood. 13.1% of children who were not stunted at age 1 or age 5 become newly stunted between the ages of 8 and 15. Our results show that children both become stunted and recover from stunting into adolescence. More attention should be paid to interventions to support healthy growth throughout childhood.

Parental height modifies the association between linear growth and neurodevelopment in infancy

AIM

To estimate the extent to which maternal and paternal height modify the association between length-for-age Z-score (LAZ) and neurodevelopmental outcomes assessed by the Bayley Scales of Infant and Toddler Development, 3rd Edition (Bayley-III).

METHODS

Baseline data from a clinical trial in 600 Nepalese infants aged six to 11 months with LAZ less than -1 were utilised. The primary exposure was the LAZ score, interaction variables were maternal and paternal height, and the outcomes were Bayley-III cognitive, language and motor scaled scores. Linear regression and generalised additive model (GAM) were used to identify potential interactions.

RESULTS

Linear regression analysis stratified by parental height categories showed that association between unit increase in LAZ and cognitive scaled score differed across maternal (normal height: ß 1.16, 95% CI; 0.75, 1.57 and short height: ß 0.67, 95% CI; 0.28, 1.05) and paternal (normal height: ß 1.32, 95% CI; 0.91, 1.72 and short height: ß 0.61, 95% CI; 0.03, 1.18) height categories. Maternal height also modified the association between LAZ and fine motor scaled score.

CONCLUSION

The association between LAZ and neurodevelopmental outcomes was attenuated when maternal and paternal height was taken into account. Parental stature should be considered when using LAZ as a proxy for neurodevelopment among infants.

Food Insecurity, Health, and Development in Children Under Age Four Years

BACKGROUND AND OBJECTIVES

Food insecurity and pediatric obesity affect young children. We examine how food insecurity relates to obesity, underweight, stunting, health, and development among children <4 years of age.

METHODS

Caregivers of young children participated in a cross-sectional survey at medical centers in 5 US cities. Inclusion criteria were age of <48 months. Exclusion criteria were severely ill or injured and private health insurance. The Household Food Security Survey Module defined 3 exposure groups: food secure, household food insecure and child food secure, and household food insecure and child food insecure. Dependent measures were obesity (weight-age >90th percentile), underweight (weight-age <5th percentile), stunting (height/length-age <5th percentile), and caregiver-reported child health and developmental risk. Multivariable logistic regression analyses, adjusted for demographic confounders, maternal BMI, and food assistance program participation examined relations between exposure groups and dependent variables, with age-stratification: 0 to 12, 13 to 24, 25 to 36, and 37 to 48 months of age.

RESULTS

Within this multiethnic sample (N = 28 184 children, 50% non-Hispanic African American, 34% Hispanic, 14% non-Hispanic white), 27% were household food insecure. With 1 exception at 25 to 36 months, neither household nor child food insecurity were associated with obesity, underweight, or stunting, but both were associated with increased odds of fair or poor health and developmental risk at multiple ages.

CONCLUSIONS

Among children <4 years of age, food insecurity is associated with fair or poor health and developmental risk, not with anthropometry. Findings support American Academy of Pediatrics recommendations for food insecurity screening and referrals to help families cope with economic hardships and associated stressors.

The association between under-nutrition, school performance and perceptual motor functioning in first-grade South African learners: The North-West Child Health Integrated with Learning and Development study

BACKGROUND

Early childhood is characterised by an immense spurt of growing and learning where under-nutrition can have adverse effects on the neuro-developmental health and school performance of children. A full understanding of the relationship between school performance and motor functioning skills and malnourishment in school beginners is still lacking.

AIM

To determine the association between indices of under-nutrition and how it relates to school performance and motor functioning skills of first-grade learners.

SETTING

North West province (NWP) of South Africa (SA).

METHOD

The baseline data of the stratified, randomised North-West Child Health Integrated with Learning and Development (NW-CHILD) longitudinal study were used. Grade 1 learners (N = 816, 420 boys, 396 girls, mean age 6.78+ years) from four school districts in the NWP of SA took part in the study. Indices of under-nutrition were determined by Z-scores (-2 standard deviation [s.d.]) for stunting (height-for-age [HAZ]) and wasting and underweight (Z-score for body mass index) using the 2007 World Health Organization reference sample. The Bruininks-Oseretsky Test of Motor Proficiency Short Form and the Visual Motor Integration fourth edition were used to assess different aspects of motor functioning, while school performance in mathematics, reading and writing was assessed by teachers according to the National South African standards of assessments.

RESULTS

Both HAZ and Z-score for weight-for-age correlated significantly with school performance and motor functioning skills (r > 2.0, p < 0.05), while visual perception was moderately associated (r < 0.30) with mathematics in HAZ and Z-score for weight-for-height (WHZ) children. Motor functioning of HAZ and WHZ children was significantly poorer (p < 0.05) compared to typical children, while underweight was not associated with any outcome variables.

CONCLUSION

Moderate forms of stunting and wasting influence school performance and motor functioning of school beginners negatively, while an association between visual perceptual abilities and inferior mathematics, reading and writing suggests a close link with inferior cognitive information processing in stunted and wasted children. These barriers should be addressed as poor scholastic success in Grade 1 may influence future school performance and the subsequent well-being of children.

Mechanisms linking height to early child development among infants and preschoolers in rural India

Stunting has been negatively associated with children's development. We examined the range of height by testing hypotheses: (a) height is positively associated with children's development, with associations moderated by inflammation and (b) home environments characterized by nurturance and early learning opportunities is positively associated with children's development over time and attenuate associations with height. Data included 513 infants (mean age 8.6 months) and 316 preschoolers (mean age 36.6 months) in rural India from a randomized controlled trial of multiple micronutrient powders (MNPs). Measures included height (height-for-age z-scores based on WHO standards), inflammation (C-reactive protein concentration >5 mg/L), nurturance (HOME Inventory), child development (Mullens Scales of Early Learning), and inhibitory control (preschoolers). Linear mixed effects models accounting for repeated measures, clustering, and confounders were used to assess associations between height and child development over time (infants: enrollment, 6 and 12 months; preschoolers: enrollment and 8 months). Moderating effects of inflammation and nurturance were tested with interaction terms. Among infants and preschoolers, height and nurturance were positively associated with all domains of child development over time, with the exception of inhibitory control. Among preschoolers, in the presence of inflammation, height was not associated with child development. Among infants, but not preschoolers, a nurturant home environment attenuated significant associations between height with fine motor and receptive language development. The mechanisms associated with children's development over time are multifactorial and include direct and indirect associations among nutrition, health, and the home environment, as supported by the Nurturing Care Framework.

Physical growth: is it a good indicator of development in early childhood in low- and middle-income countries?

Background

Growth and early development (ECD) are vital outcomes for children. This study aimed to examine the association between child growth and overall development in children aged 3 to 5 years in low- and middle-income countries.

Methods

A secondary analysis of nationally representative data collected in UNICEF’s Multiple Indicator Cluster Surveys (MICS) and national Demographic and Health Surveys (DHS). The early development of children aged 3 to 5 years from the randomly selected households was ascertained using a 10-item scale which assessed four developmental domains: language-cognitive, physical, socio-emotional, and approaches to learning with a total development score ranging from 0 (the least optimal) to 10 (the most optimal). Children’s growth, the height-for-age Z score (HAZ), was calculated using the WHO Child Growth Standards. Unadjusted (Pearson’s correlation coefficient, r) and adjusted estimations (standardised mean difference (SMD) adjusted for child sex, child age, and household wealth index) of the magnitude of the association between HAZ and ECD scores were calculated for each country.

Results

Data contributed by 178,393 children aged 36 to 59 months from 55 countries were included in the analyses. The pooled r between HAZ and standardised ECD scores was 0.12 and the pooled adjusted SMD was 0.06. The r ranged from ~ 0 in Barbados, Lebanon, and Moldova to 0.32 in Pakistan and 0.36 in Nigeria. Overall, 47/55 countries had correlation coefficients less than the cut-off for a small association. The adjusted SMDs were ~ 0 in 20 countries. All SMDs were lower than the cut-off for a small effect size. The magnitudes of the association were highest in South Asia and lowest in Middle East and North Africa, and lowest in the highest HDI group.

Conclusions

The association between growth and development in early childhood appears to be primarily a co-occurrence because the magnitude of the association varies among settings from no association in higher-income countries to a moderate level in low-income countries. In low-income countries, interventions targeting child growth and ECD should be integrated given their common risks frequency in these settings. Overall, growth is not a sensitive and therefore suitable indicator of child development.

Electronic supplementary material

The online version of this article (10.1186/s12887-019-1654-9) contains supplementary material, which is available to authorized users.

Association between stunting and early childhood development among children aged 36-59 months in South Asia

Stunting (length‐for‐age z score < −2) before 2 years of age has shown associations with poor child developmental indicators, but information at the population level is scarce in South Asia, the region with the highest burden of stunting. We examined associations between z scores (i.e., height for age [HAZ], weight for age [WAZ], and weight for height [WHZ]) and undernutrition (i.e., stunting [HAZ < −2], wasting [WHZ < −2], and underweight [WAZ < −2]) with learning/cognition and social–emotional development among children 36–59 months of age. Data from Multiple Indicator Cluster Surveys in Bangladesh (n = 8,659), Bhutan (n = 2,038), Nepal (n = 2,253), and Pakistan (Punjab n = 11,369 and Sindh n = 6,718) were used. Children were considered developmentally “on‐track” in learning/cognition or social–emotional domains if they met specific early child development criteria. Meta‐analysis was conducted to examine regional associations, adjusting for socio‐economic status, early childhood education, and quality of care. In a pooled sample, on‐track learning/cognition development was positively associated with HAZ (OR = 1.17, 95% CI [1.07, 1.27]) and WAZ (OR = 1.18, 95% CI [1.07, 1.31]) and negatively associated with stunting (OR = 0.72, 95% CI [0.60, 0.86]) and underweight (OR = 0.75, 95% CI [0.66, 0.86]) but not associated with WHZ or wasting. On‐track development of social–emotional domain was not associated with any z scores or undernutrition indicators. Across several countries of South Asia, stunted children were less likely to be developmentally “on track” for learning/cognition. It is likely that interventions that prevent stunting may benefit child development, leading to significant individual and societal gains given the large burden of child stunting in regions like South Asia.

Long run height and education implications of early life growth faltering: a synthetic panel analysis of 425 birth cohorts in 21 low- and middle-income countries

Background

We estimated the associations between exposure to early life growth faltering at the population level and adult height and education outcomes in a sample of 21 low- and middle-income countries.

Methods

We conducted a synthetic panel analysis of 425 birth cohorts across 126 regions in 21 LMICs surveyed in the Demographic and Health Surveys (DHS) both as children and as adults. Data from historic (1987–1993) DHS survey rounds were used to compute average height-for-age z-scores at the province-birth-year level. Cohort measures of early life growth were then linked to adult height and educational attainment measures collected on individuals from the same cohorts in the 2006-2014 DHS survey rounds. The primary exposure of interest was population-level early life growth (region-birth year average HAZ) and growth faltering (region-birth year stunting prevalence). Multivariable linear regression models were used to estimate the associations between adult outcomes and population-level measures of early life linear growth.

Results

The average cohort height-for-age z-score (HAZ) in childhood was − 1.53 [range: − 2.73, − 0.348]. In fully adjusted models, each unit increase in cohort childhood HAZ was associated with a 2.0 cm [95% CI: 1.09–2.9] increase in adult height, with larger associations for men than for women. Evidence for the association between early childhood height and adult educational attainment was found to be inconclusive (0.269, 95% CI: [− 0.68–1.22]).

Conclusions

While early childhood linear growth at the cohort level appears to be highly predictive of adult height, the empirical association between early life growth and adult educational attainment seems weak and heterogeneous across countries.

Registration

This study was registered on May 10, 2017 at the ISRCTN Registry (http://www.isrctn.com), registration number ISRCTN82438662.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-7203-5) contains supplementary material, which is available to authorized users.

Effect of in utero exposure to HIV and antiretroviral drugs on growth in HIV-exposed uninfected children: a systematic review and meta-analysis protocol

INTRODUCTION

HIV-exposed uninfected (HEU) children have higher morbidity and mortality compared with HIV unexposed uninfected children. Despite the fact that malnutrition contributes to about half of all infant deaths below 5 years of age in low-income and middle-income countries and that growth impairment has been reported in the HEU population, the spectrum of growth disorders associated with HIV and antiretroviral therapy (ART) exposure during the in utero and perinatal periods is yet to comprehensively summarised among the global HEU population. This protocol for a systematic review and meta-analysis aims to critically synthesise data concerning the prevalence of underweight, stunting and wasting at different ages in the global HEU population.

METHODS AND ANALYSIS

Medline, EMBASE, Cochrane Library, TOXLINE, WHO Global Index Medicus and the Web of Science will be searched for relevant articles published between 1 January 1989 and 1 December 2017 without language restriction. In addition, conference abstracts and reference lists of eligible papers and relevant review articles will be screened. Authors will screen and select studies, extract data, assess the risk of bias as well as studies individually for heterogeneity. Study-specific estimates will be pooled through a random-effects meta-analysis model for studies that are clinically homogeneous while funnel plots and Egger's test will be used to detect publication bias. Results will be presented by ART availability period, country income levels and mode of breastfeeding.

ETHICS AND DISSEMINATION

Ethical approval will not be required for this study because it will be based on published data. The final report of this study will be published in a peer-reviewed journal and presented at scientific conferences. This review will summarise the evidence and quantify the problem of growth impairment in HEU infants and so shed more light on our understanding of the higher morbidity and mortality in this growing population.

PROSPERO REGISTRATION NUMBER

CRD42018091762.

Assessing associational strength of 23 correlates of child anthropometric failure: An econometric analysis of the 2015-2016 National Family Health Survey, India

Despite the broad consensus that investments in nutrition-sensitive programmes are required to reduce child undernutrition, in practice empirical studies and interventions tend to focus on few nutrition-specific risk factors in isolation. The 2015-16 National Family Health Survey provides the first opportunity in more than a decade to conduct an up-to-date comprehensive evaluation of the relative importance of various maternal and child health and nutrition (MCHN) factors in respect to child anthropometric failures in India. The primary analysis included 140,444 children aged 6-59 months with complete data on 20 MCHN factors, and the secondary analysis included a subset of 25,603 children with additional paternal data. Outcome variables were stunting, underweight and wasting. We conducted logistic regression models to first evaluate each correlate separately in age- and sex-adjusted models, and then jointly in a mutually adjusted model. For all anthropometric failures, indicators of past and present socioeconomic conditions showed the most robust associations. The strongest correlates for stunting were short maternal stature (OR: 4.39; 95%CI: 4.00, 4.81), lack of maternal education (OR: 1.74; 95%CI: 1.60, 1.89), low maternal BMI (OR: 1.64; 95%CI: 1.54, 1.75), poor household wealth (OR: 1.25; 95%CI: 1.15, 1.35) and poor household air quality (OR: 1.22; 95%CI: 1.16, 1.29). Weaker associations were found for other correlates, including dietary diversity, vitamin A supplementation and breastfeeding initiation. Paternal factors were also important predictors of anthropometric failures, but to a lesser degree than maternal factors. The results remained consistent when stratified by children's age (6-23 vs 24-59 months) and sex (girls vs boys), and when low birth weight was additionally considered. Our findings indicate the limitation of nutrition-specific interventions. Breaking multi-generational poverty and improving environmental factors are promising investments to prevent anthropometric failures in early childhood.

Drought and child undernutrition in Ethiopia: A longitudinal path analysis

BACKGROUND

The increase in the frequency of extreme events due to climate change poses a serious challenge to achieving the Sustainable Development Goal 2 of ending hunger by 2030. While evidence exists on the impact of drought on under-five children, its effect during late childhood and early adolescence remains less investigated.

OBJECTIVE

This study estimates the impact of concurrent and long-term exposure to drought on linear growth during late childhood and early adolescence.

METHODS

Four rounds (2002-2013) of data from the young lives Cohort Study dataset (n = 2000) was used. The associations of concurrent and long-term exposure to drought and Height-for-age z-score was analysed using structural equation modelling techniques. The study also explored the mediating role of interim period growth in the association of early exposure to drought and undernutrition at later age and the role of the Productive Safety Net Program in buffering the impact of drought on child nutrition.

RESULTS

Results show that both concurrent and long-term exposure to drought was negatively associated with Height-for-age z-score (p < 0.001). Exposure to drought at age 5, 8, and 12 years is associated with lower Height-for-age z- score at age 5, 8, and 12 years respectively. Exposure to drought at age 5 years was also negatively associated with Height-for-age z-score at age 12 years (p < 0.001). This association was mainly indirect (89%) and mediated through reduced child growth in subsequent years. Participation in productive safety net program by drought-affected children reduces but does not completely offset the negative effects of drought on Height-for-age z-score (p < 0.1). Moreover, girls were more likely to suffer poor growth than boys.

CONCLUSION

Drought exposure after the 1,000 days window could have a lasting impact on child growth. Given the importance of this period for child physical and mental development, children beyond the 1,000 days window should also be a focus of disaster relief programs.

Low socioeconomic status and severe obesity are linked to poor cognitive performance in Malaysian children

Background

Socioeconomic factors and nutritional status have been associated with childhood cognitive development. However, previous Malaysian studies had been conducted with small populations and had inconsistent results. Thus, this present study aims to determine the association between socioeconomic and nutritional status with cognitive performance in a nationally representative sample of Malaysian children.

Methods

A total of 2406 Malaysian children aged 5 to 12 years, who had participated in the South East Asian Nutrition Surveys (SEANUTS), were included in this study. Cognitive performance [non-verbal intelligence quotient (IQ)] was measured using Raven’s Progressive Matrices, while socioeconomic characteristics were determined using parent-report questionnaires. Body mass index (BMI) was calculated using measured weight and height, while BMI-for-age Z-score (BAZ) and height-for-age Z-score (HAZ) were determined using WHO 2007 growth reference.

Results

Overall, about a third (35.0%) of the children had above average non-verbal IQ (high average: 110–119; superior: ≥120 and above), while only 12.2% were categorized as having low/borderline IQ (< 80). Children with severe obesity (BAZ > 3SD), children from very low household income families and children whose parents had only up to primary level education had the highest prevalence of low/borderline non-verbal IQ, compared to their non-obese and higher socioeconomic counterparts. Parental lack of education was associated with low/borderline/below average IQ [paternal, OR = 2.38 (95%CI 1.22, 4.62); maternal, OR = 2.64 (95%CI 1.32, 5.30)]. Children from the lowest income group were twice as likely to have low/borderline/below average IQ [OR = 2.01 (95%CI 1.16, 3.49)]. Children with severe obesity were twice as likely to have poor non-verbal IQ than children with normal BMI [OR = 2.28 (95%CI 1.23, 4.24)].

Conclusions

Children from disadvantaged backgrounds (that is those from very low income families and those whose parents had primary education or lower) and children with severe obesity are more likely to have poor non-verbal IQ. Further studies to investigate the social and environmental factors linked to cognitive performance will provide deeper insights into the measures that can be taken to improve the cognitive performance of Malaysian children.

The association of early linear growth and haemoglobin concentration with later cognitive, motor, and social-emotional development at preschool age in Ghana

It is important to identify the periods during childhood when exposure to environmental risk factors results in long-term neurodevelopmental deficits. Stunting and anaemia may be sensitive indicators of exposure to such risks. In a prospective cohort enrolled before birth, we investigated the association of developmental scores at 4-6 years with (a) birth length and linear growth during three postnatal periods and (2) haemoglobin (Hb) concentration at three time points. Children were participants in a follow-up study of a randomized controlled trial of nutritional supplementation in Ghana. At 4-6 years, cognitive, motor, and social-emotional developments were assessed using standard tests adapted for this population. We estimated the associations of length-for-age z-score (LAZ) at birth and postnatal linear growth (n = 710) and Hb (n = 617) with developmental scores in regression models, using multistage least squares analysis to calculate uncorrelated residuals for postnatal growth. Cognitive development at 4-6 years was significantly associated with LAZ at birth (β = 0.12, 95% CI = 0.05, 0.19), ΔLAZ from 6 to 18 months (β = 0.16, 95% CI = 0.04, 0.28), and Hb at 18 months (β = 0.13, 95% CI = 0.06, 0.20), but not with ΔLAZ during 0-6 months, ΔLAZ from 18 months to 4-6 years, Hb at 6 months, or Hb at 4-6 years. No evidence of associations with motor or social-emotional development were found. These results suggest that in similar contexts, the earlier periods prior to birth and up to 18 months are more sensitive to risk factors for long-term cognitive development associated with LAZ and Hb compared with later childhood. This may inform the optimal timing of interventions targeting improved cognitive development.

Meeting the World Health Organization Maternal Antenatal Care Guidelines Is Associated with Improved Early and Middle Childhood Cognition in Ethiopia

OBJECTIVE

To assess the association between meeting the World Health Organization (WHO) maternal antenatal care attendance guidelines and early and middle childhood cognition among impoverished Ethiopian children.

STUDY DESIGN

A total of 1914 impoverished Ethiopian children from the Young Lives longitudinal cohort study were included. Childhood cognition was assessed via the Cognitive Development Assessment (CDA) and Peabody Picture Vocabulary Test (PPVT) at ages 4-5 years; PPVT, Early Grade Reading Assessment (EGRA), and Math Test at ages 7-8 years; and PPVT, Math Test, and Reading Test at ages 11-12 years. Linear regression models were used to examine the association between maternal antenatal care attendance and childhood academic achievement test scores.

RESULTS

In the univariable analysis, children of mothers who received the WHO recommended 4+ antenatal care visits or received the WHO recommended first antenatal care visit during the first trimester scored higher on all academic achievement tests. In the multivariable analysis, children of mothers who received 4+ antenatal care visits scored significantly higher on the CDA at ages 4-5 years and Math Test at ages 7-8 years. Children of mothers who received antenatal care in the first trimester scored higher on the CDA at ages 4-5 years and Math Test scores at ages 11-12 years. Children of mothers who received both antenatal care in the first trimester and 4+ antenatal care visits scored significantly higher on the CDA at ages 4-5 years and Math Test at both ages 7-8 and 11-12 years.

CONCLUSIONS

Children of mothers who received the WHO recommended number and timing of antenatal care visits had significantly higher academic achievement scores across multiple domains during early and middle childhood. Promotion of antenatal care visit attendance may improve cognition through middle childhood.

Child development in the context of biological and psychosocial hazards among poor families in Bangladesh

It is well established that low resource environments early in life can predispose children to adverse health and compromised developmental outcomes. We explore possible mechanistic pathways underlying poor developmental outcomes in children growing up in a low resource setting in urban Bangladesh. We tested associations between psychosocial risks, namely maternal distress and poor caregiving experiences, and biological risks, namely poor growth (HAZ) and inflammation (C-reactive protein: CRP), and children’s developmental outcomes. Child development was measured using the Mullen Scales of Early Learning (MSEL) at 6 and 27 months in one cohort, and using the MSEL and Wechsler Preschool and Primary Scale of Intelligence (WPPSI) at 36 and 60 months respectively in another cohort. In the younger cohort, we found that more inflammation (estimated by the child’s CRP level at four months) predicted lower receptive language scores at 6 months, while more frequent caregiving interactions predicted higher receptive language scores at 6 months. In the older cohort, we found that at 27 months, a child’s growth measured by his or her current HAZ was positively associated with gross motor, visual reception, receptive language, and expressive language scores. In the oldest cohort, we found that higher HAZ and more frequent stimulating activities in the home predicted higher motor and language scores, whereas more inflammation (as estimated by CRP over the first two years of life) predicted lower motor scores at 36 months. At 60 months, we found that HAZ and caregiving experiences were positively associated with verbal IQ, whereas inflammation was negatively associated with verbal IQ. This work identifies malnutrition, inflammation, and caregiving as potential sites of intervention to improve neurodevelopment in children growing up in global poverty.

Growth in the first 5 years after antiretroviral therapy initiation among HIV-infected children in the IeDEA West African Pediatric Cohort

OBJECTIVE

To describe growth evolution and its correlates in the first 5 years of antiretroviral therapy (ART) initiation among HIV-infected children followed up in West Africa.

METHODS

All HIV-infected children younger than 10 years followed in the IeDEA pWADA cohort while initiating ART, with at least one anthropometric measurement within the first 5 years of treatment were included in the study. Growth was described according to the WHO child growth standards, using Weight-for-age Z-score (WAZ), Height-for-age Z-score (HAZ) and Weight-for-Height/BMI-for-age Z-score (WHZ/BAZ). Growth evolution and its correlates, measured at ART initiation, were modelled in individual linear mixed models for each anthropometric indicator, with a spline term added at the 12-, 24- and 9-month time point for WAZ, HAZ and WHZ/BAZ, respectively.

RESULTS

Among the 4156 children selected (45% girls, median age at ART initiation 3.9 years [IQR interquartile range 1.9-6.6], and overall 68% malnourished at ART initiation), important gains were observed in the first 12, 24 and 9 months on ART for WAZ, HAZ and WHZ/BAZ, respectively. Correlates at ART initiation of a better growth evolution overtime were early age (<2 years of age), severe immunodeficiency for age, and severity of malnutrition.

CONCLUSIONS

Growth evolution is particularly strong within the first 2 years on ART but slows down after this period. Weight and height gains help to recover from pre-ART growth deficiency but are insufficient for the most severely malnourished. The first year on ART could be the best period for nutritional interventions to optimize growth among HIV-infected children in the long-term.

Morbidity, mortality, and long-term consequences associated with diarrhoea from Cryptosporidium infection in children younger than 5 years: a meta-analyses study

Background

The protozoan Cryptosporidium is a leading cause of diarrhoea morbidity and mortality in children younger than 5 years. However, the true global burden of Cryptosporidium infection in children younger than 5 years might have been underestimated in previous quantifications because it only took account of the acute effects of diarrhoea. We aimed to demonstrate whether there is a causal relation between Cryptosporidium and childhood growth and, if so, to quantify the associated additional burden.

Methods

The Global Burden of Diseases, Injuries, and Risk Factors study (GBD) 2016 was a systematic and scientific effort to quantify the morbidity and mortality associated with more than 300 causes of death and disability, including diarrhoea caused by Cryptosporidium infection. We supplemented estimates on the burden of Cryptosporidium in GBD 2016 with findings from a systematic review of published and unpublished cohort studies and a meta-analysis of the effect of childhood diarrhoea caused by Cryptosporidium infection on physical growth.

Findings

In 2016, Cryptosporidium infection was the fifth leading diarrhoeal aetiology in children younger than 5 years, and acute infection caused more than 48 000 deaths (95% uncertainty interval [UI] 24 600–81 900) and more than 4·2 million disability-adjusted life-years lost (95% UI 2·2 million–7·2 million). We identified seven data sources from the scientific literature and six individual-level data sources describing the relation between Cryptosporidium and childhood growth. Each episode of diarrhoea caused by Cryptosporidium infection was associated with a decrease in height-for-age Z score (0·049, 95% CI 0·014–0·080), weight-for-age Z score (0·095, 0·055–0·134), and weight-for-height Z score (0·126, 0·057–0·194). We estimated that diarrhoea from Cryptosporidium infection caused an additional 7·85 million disability-adjusted life-years (95% UI 5·42 million–10·11 million) after we accounted for its effect on growth faltering—153% more than that estimated from acute effects alone.

Interpretation

Our findings show that the substantial short-term burden of diarrhoea from Cryptosporidium infection on childhood growth and wellbeing is an underestimate of the true burden. Interventions designed to prevent and effectively treat infection in children younger than 5 years will have enormous public health and social development impacts.

Funding

The Bill & Melinda Gates Foundation.

Nutritional, Socioeconomic, and Delivery Characteristics Are Associated with Neurodevelopment in Tanzanian Children

OBJECTIVES

To evaluate the hypothesis that various maternal, socioeconomic, delivery, and infant nutritional characteristics are associated with early childhood development in young Tanzanian children.

STUDY DESIGN

We performed a prospective cohort study among 206 HIV-exposed, uninfected and 247 HIV-unexposed Tanzanian infants who had been enrolled in 2 separate micronutrient trials (NCT00197730 and NCT00421668). Trained nurses administered culturally modified Bayley Scales of Infant and Toddler Development, 3rd edition (BSID-III), to evaluate cognitive, motor, and language development at 15 months of age. This analysis explored predictors of BSID-III z-scores using multivariable linear regression.

RESULTS

Among maternal determinants, we found that low maternal height predicted all BSID-III domains in HIV-unexposed children; low maternal education predicted lower cognitive (standardized mean difference, -0.41; 95% CI, -0.74 to -0.08) and lower gross motor scores (standardized mean difference, -0.32; 95% CI, -0.61 to -0.04) in HIV-exposed children. Among delivery characteristics, facility delivery predicted higher cognitive scores (standardized mean difference, 1.36; 95% CI, 0.26-2.46); and oxytocin administration predicted lower fine motor scores (standardized mean difference, -0.48; 95% CI, -0.87 to -0.09) in HIV-exposed children. Higher length-for-age z-scores at 6 weeks of age predicted better cognitive (standardized mean difference, 0.15; 95% CI, 0.01-0.29) and expressive language scores (standardized mean difference, 0.16; 95% CI, 0.02-0.29) at 15 months in HIV-exposed infants.

CONCLUSIONS

This hypothesis-generating study found significant associations between nutritional status and health of the mother and child, and maternal educational attainment, with direct measures of early childhood development at 15 months of age. In addition, several aspects of delivery (facility birth and oxytocin administration) were associated with early childhood development. Future intervention trials should focus on modifiable maternal, infant, and obstetric factors to strengthen the evidence base concerning early childhood development.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00197730 and NCT00421668.

Adaptation of the Mullen Scales of Early Learning for use among infants aged 5- to 24-months in rural Gambia

Infants in low‐resource settings are at heightened risk for compromised cognitive development due to a multitude of environmental insults in their surroundings. However, the onset of adverse outcomes and trajectory of cognitive development in these settings is not well understood. The aims of the present study were to adapt the Mullen Scales of Early Learning (MSEL) for use with infants in a rural area of The Gambia, to examine cognitive development in the first 24‐months of life and to assess the association between cognitive performance and physical growth. In Phase 1 of this study, the adapted MSEL was tested on 52 infants aged 9‐ to 24‐months (some of whom were tested longitudinally at two time points). Further optimization and training were undertaken and Phase 2 of the study was conducted, where the original measures were administered to 119 newly recruited infants aged 5‐ to 24‐months. Infant length, weight and head circumference were measured concurrently in both phases. Participants from both phases were split into age categories of 5–9 m (N = 32), 10–14 m (N = 92), 15–19 m (N = 53) and 20–24 m (N = 43) and performance was compared across age groups. From the ages of 10–14 m, Gambian infants obtained lower MSEL scores than US norms. Performance decreased with age and was lowest in the 20–24 m old group. Differential onsets of reduced performance were observed in the individual MSEL domains, with declines in visual perception and motor performance detected as early as at 10–14 months, while reduced language scores became evident after 15–19 months of age. Performance on the MSEL was significantly associated with measures of growth.

Neither n-3 Long-Chain PUFA Supplementation of Mothers through Lactation nor of Offspring in a Complementary Food Affects Child Overall or Social-Emotional Development: A 2 × 2 Factorial Randomized Controlled Trial in Rural Ethiopia

BACKGROUND

The n-3 (ω-3) long-chain polyunsaturated fatty acid (LC-PUFA) docosahexaenoic acid (DHA) is essential for optimal brain development. There is a lack of evidence on the effect of postnatal n-3 LC-PUFA supplementation on child development in low-income countries.

OBJECTIVE

We evaluated the efficacy of fish-oil supplementation through lactation or complementary food supplementation on the development of children aged 6-24 mo in rural Ethiopia.

METHODS

We conducted a double-blind randomized controlled trial of n-3 LC-PUFA supplementation for 12 mo using fish-oil capsules [maternal intervention: 215 mg DHA + 285 mg eicosapentaenoic acid (EPA)] or a fish-oil-enriched complementary food supplement (child intervention: 169 mg DHA + 331 mg EPA). In total, 360 pairs of mothers and infants aged 6-12 mo were randomly assigned to 4 arms: maternal intervention and child control, child intervention and maternal control, maternal and child intervention, and maternal and child control. Primary outcomes were overall developmental performance with the use of a culturally adapted Denver II test that assesses personal-social, language, fine-motor, and gross-motor domains and social-emotional developmental performance using the Ages and Stages Questionnaire: Social Emotional at baseline and at 6 and 12 mo. We used mixed-effects models to estimate intervention effects on developmental performance over time (intervention × time interaction).

RESULTS

The evolution in overall and social-emotional developmental performance over time did not differ across study arms (intervention × time: F = 1.09, P = 0.35, and F = 0.61, P = 0.61, respectively). Effects did not change after adjustment for child age, birth order, and nutritional status; maternal age and education; wealth; family size; and breastfeeding frequency. Children's developmental performance significantly decreased during study follow-up (β: -0.03 SDs/mo; 95% CI: -0.04, -0.01 SD/mo; P < 0.01).

CONCLUSIONS

n-3 LC-PUFA supplementation does not affect overall or social-emotional development of children aged 6-24 mo in a low-income setting. Follow-up of the cohort is recommended to determine whether there are long-term effects of the intervention. This trial was registered at clinicaltrials.gov as NCT01817634.

Perspective: What Does Stunting Really Mean? A Critical Review of the Evidence

The past decade has seen an unprecedented increase in attention to undernutrition, and drastically reducing child stunting has become a global development objective. The strong focus on linear growth retardation and stunting has enabled successful advocacy for nutrition, but with this focus has come some confusion and misunderstanding about the meaning of linear growth retardation and stunting among researchers, donors, and agencies active in nutrition. Motivated by the belief that a sharp focus will further accelerate progress in reducing undernutrition, we critically reviewed the evidence. The global attention to stunting is based on the premise that any intervention aimed at improving linear growth will subsequently lead to improvements in the correlates of linear growth retardation and stunting. Current evidence and understanding of mechanisms does not support this causal thinking, with 2 exceptions: linear growth retardation is a cause of difficult births and poor birth outcomes. Linear growth retardation is associated with (but does not cause) delayed child development, reduced earnings in adulthood, and chronic diseases. We thus propose distinguishing 2 distinctly different meanings of linear growth retardation and stunting. First, the association between linear growth retardation (or stunting) and other outcomes makes it a useful marker. Second, the causal links with difficult births and poor birth outcomes make linear growth retardation and stunting outcomes of intrinsic value. In many cases a focus on linear growth retardation and stunting is not necessary to improve the well-being of children; in many other cases, it is not sufficient to reach that goal; and for some outcomes, promoting linear growth is not the most cost-efficient strategy. We appeal to donors, program planners, and researchers to be specific in selecting nutrition outcomes and to target those outcomes directly.

Sanitation in Rural India: Exploring the Associations between Dwelling Space and Household Latrine Ownership

In 2017, the Joint Monitoring Programme estimated that 520 million people in India were defecating in the open every day. This is despite efforts made by the government, Non-Governmental Organizations (NGOs), and multilaterals to improve latrine coverage throughout India. We hypothesize that this might be because current interventions focus mostly on individual-level determinants, such as attitudes and beliefs, instead of considering all possible social determinants of latrine ownership. Given this, we ask two questions: what is the association between the amount of dwelling space owned by households in rural India and their likelihood of toilet ownership and what proportion of the variation in household latrine ownership is attributable to villages and states? We used multilevel modeling and found significant associations between the amount of household dwelling space and the likelihood of latrine ownership. Furthermore, considerable variation in latrine ownership is attributable to villages and states, suggesting that additional research is required to elucidate the contextual effects of villages and states on household latrine ownership. Thus, sanitation interventions should consider household dwelling space and village and state context as important social determinants of latrine ownership in rural India. Doing so could bolster progress towards Sustainable Development Goal (SDG) 6.

Mother's nutrition-related knowledge and child nutrition outcomes: Empirical evidence from Nigeria

BACKGROUND

Nutrition outcomes among young children in Nigeria are among the worse globally. Mother's limited knowledge about food choices, feeding, and health care seeking practices contributes significantly to negative nutrition outcomes for children in most developing countries. Much less is known about the relationship between mother's nutrition-related knowledge and child nutritional outcomes in rural Nigeria. This paper investigates therefore: (i) the association of mother's nutrition-related knowledge with nutrition outcomes of young children living in rural Nigeria, where access to education is limited, and (ii) whether mother's education has a complementary effect on such knowledge in producing positive child nutrition outcomes in such settings.

METHODS

Using the Demographic and Health Survey data for Nigeria, we employ both descriptive and regression analyses approaches in analyzing the study's objectives. In particular, we apply ordinary least square (OLS) to investigate the association of mother's nutrition-related knowledge with child HAZ and WHZ while controlling for maternal, child, household and regional characteristics. An index was constructed for mother's nutrition-related knowledge using information on dietary practices, disease treatment and prevention, child immunization, and family planning.

RESULTS

We found that mother's knowledge is independently and positively associated with HAZ and WHZ scores in young children. Higher levels of mother's education, typically above primary, have a significant, positive association with child HAZ and WHZ scores. We argue that mother's knowledge of health and nutrition may substitute for education in reducing undernutrition in young children among populations with limited access to formal education. However, the present level of mother's education in rural Nigeria appears insufficient to reinforce knowledge in producing better nutrition outcomes for children.

CONCLUSIONS

This study suggests promotion of out-of-school (informal) education, such as adult literacy and numeracy classes where women without formal education can gain health and nutrition knowledge, and practices that could enhance child nutrition outcomes in Nigeria.

Effect of antenatal and infant micronutrient supplementation on middle childhood and early adolescent development outcomes in Tanzania

Background:

There is growing evidence that nutritional interventions in the first 1,000 days of life may influence long-term health and development outcomes. Few studies have examined the effect of maternal and infant micronutrient supplementation on development outcomes in sub-Saharan Africa.

Methods:

We conducted a follow-up study of two randomized trials of antenatal and infant micronutrient supplementation conducted in Dar es Salaam, Tanzania. We assessed the effect of maternal multiple micronutrient (MMN) supplementation in pregnancy on development of children at 11–14 years of age. We also examined the effect of infant zinc and MMN supplementation on development at 6–8 years of age. We use generalized linear models to assess standardized mean differences (SMDs) in general intelligence, executive function and mental health scores.

Results:

We followed-up 446 children whose mothers were enrolled in the maternal MMN supplementation trial and 365 children who were enrolled in the infant zinc and MMN supplementation trial. We found no effect of maternal MMN supplementation on general intelligence (SMD: −0.03; 95% CI: −0.15, 0.09), executive function (SMD: 0.00; 95% CI: −0.11, 0.11) and mental health scores (SMD: 0.06; 95% CI: −0.10, 0.22). We also found no effect of either infant zinc or MMN supplementation on any of the three development domains (p-values >0.05).

Conclusions:

We found that antenatal MMN supplementation and infant zinc and MMN supplementation did not have a large effect on development outcomes in middle childhood and early adolescence in Tanzania.

El Sahly H, Calvimontes M, Olson D, M. Munoz F, J. Asturias E. Responding to the Zika Epidemic: Preparation of a Neurodevelopmental Testing Protocol to Evaluate Young Children in Rural Guatemala

The ongoing Zika virus (ZIKV) epidemic in Latin America presented a unique opportunity to develop a neurodevelopmental assessment protocol for children in a lower middle-income country. Although studies of neurodevelopment in young children have taken place in many diverse global settings, we are not aware of any study that has provided a high level of detail about how a measure was selected and then specifically translated and adapted in a low-resource setting. Here, we describe considerations in measurement selection and then the process of translation and adaptation to assess neurodevelopmental outcomes of infants and young children with postnatal exposure to ZIKV in rural Guatemala. We provide a framework to other research teams seeking to develop similar assessment models across the globe.

Quality of care and suspected developmental delay among children aged 1-59 months: a cross-sectional study in 8 counties of rural China

BACKGROUND

The data about quality of care of more than 70 countries were available from UNICEF but little was known about China. We examined the status about quality of care and explored its associations with developmental outcomes in Chinese children.

METHODS

A cross-sectional study with probability proportional to size sampling method was conducted in 8 counties of rural China. A total 1927 children were assessed on development status using Ages and Stages Questionnaires-Chinese (ASQ-C) based on Chinese normative data. Nutritional status was derived from the anthropometric method following WHO guidelines. Caregivers were interviewed through household questionnaires from UNICEF's 5th Multiple Indicator Cluster Survey to understand the quality of care, including the status of availability of children's books, availability of playthings, support for learning, fathers' support for learning and inadequate care. Moreover, quality of care was explored to be categorized into three levels (poor, medium and good) for overall assessment. Multivariable logistic regression model was applied to estimate the odds ratios and 95% confidence intervals between quality of care and suspected developmental delay (SDD) after adjustment for potential confounding variables.

RESULTS

The proportions of availability of children's books, playthings, support for learning, fathers' support for learning and inadequate care were 36.8, 91.3, 83.1, 16.4 and 4.9%, respectively. When compared to available data of more than 70 countries and areas, the quality of care in rural China was in the middle to upper level. After adjustment for potential confounding variables, multivariable analysis showed that SDD in overall ASQ remained negatively associated with availability of children's books (odds ratio [OR] and 95% confidence interval [CI]: 1.64 [1.27-2.12]), playthings (OR and 95% CI: 2.23 [1.52-3.27]) and support for learning (OR and 95% CI: 1.81 [1.06-3.10]). When compared with children under good quality of care, children under medium and poor quality of care had higher prevalence of SDD in overall ASQ (OR and 95% CI: 1.59 [1.21-2.07]; 3.05 [1.96-4.74]).

CONCLUSIONS

Quality of care in rural China still had scope for improvement. Better quality of care had negative associations with SDD.

Dietary diversity and nutritional status among children in rural Burkina Faso

Background

Burkina Faso has a seasonal malnutrition pattern, with higher malnutrition prevalence during the rainy season when crop yields are low. We investigated the association between dietary diversity and nutritional status among children aged 6-59 mo during the low crop yield season in rural Burkina Faso to assess the role of dietary diversity during the lean season on childhood nutritional status.

Methods

Caregivers reported the dietary diversity of the past 7 d, consisting of 11 food groups, summed into a scale. Anthropometric measurements were taken from all children. Height-for-age (HAZ), weight-for-height (WHZ) and weight-for-age (WAZ) z-scores were calculated based on 2006 WHO standards. Stunting, wasting and underweight were defined as HAZ, WHZ and WAZ <-2 SD, respectively. Multivariable regression models adjusting for potential confounders including household food insecurity and animal ownership were used to assess the relationship between anthropometric indices and dietary diversity.

Results

Of 251 children enrolled in the study, 20.6% were stunted, 10.0% wasted and 13.9% underweight. Greater dietary diversity was associated with greater HAZ (SD 0.14, 95% CI 0.04 to 0.25) among all children. There was no association between dietary diversity and wasting or mid-upper arm circumference in this study.

Conclusions

Increasing dietary diversity may be an approach to reduce the burden of stunting and chronic malnutrition among young children in regions with seasonal food insecurity.

Early linear growth retardation: results of a prospective study of Zambian infants

BACKGROUND

Linear growth retardation is the most dominant nutritional problem globally. We aimed to describe linear growth trajectory among infants under 2 years of age using the WHO growth velocity standards.

METHOD

This was a prospective cohort study of infants enrolled at 6 weeks of age and followed up for up to 24 months in Kamwala Urban Health Centre, Lusaka, Zambia. The study was conducted between April 2013 and March 2015. Infants were enrolled if they were 6-12 weeks of age and the mother was willing to participate voluntarily and provided informed consent. Anthropometric data were collected at scheduled clinic visits at 1 month, 2 months, 3 months, then quarterly until the infant was 24 months old. We defined linear growth velocity as the rate of change in height. We estimated linear growth velocity as the first derivative of the penalized cubic spline mixed effects model.

RESULTS

A total of 338 children were included in the analysis. Of these, 185 (54.7%) were female, 115 (34.1%) were born to HIV positive mothers and thus classified as HIV Exposed (HE). The mean age of children at enrollment was 1.6 months (SD = 0.15). On average, the growth velocity for 3-month length increments conditional on age were 0-3 months = 2.97 cm/3mo (95%CI = 2.69, 3.25); 3-6 months = 2.62 cm/3mo (95%CI = 2.38, 2.87); 6-9 months = 1.57 cm/3mo (95%CI = 1.43, 1.71); 9-12 months = 1.18 cm/3mo (95%CI = 1.08, 1.28); 12-15 month = 1.14 cm/3mo (95%CI = 1.02, 1.27); 15-18 months = 0.87 cm/3mo (95%CI = 0.79, 0.96); 18-21 months = 0.80 cm/3mo (95%CI = 0.72, 0.89); and 21-24 months = 0.86 cm/3mo (95%CI = 0.77, 0.96). For both boys and girls, the growth velocity in our cohort were consistently below the 3rd percentile of the WHO linear growth velocity standard. The estimated mean height and the age at which growth begins to falter were 68.6 cm (95%CI = 68.0, 69.2) and 13.6 months (95%CI = 13.2, 14.1) respectively.

CONCLUSION

We found slower rate of growth among otherwise healthy Zambian infants. The data suggests that growth retardation is universal and profound in this cohort and may have already been occurring in utero.

Effects of improved drinking water quality on early childhood growth in rural Uttar Pradesh, India: A propensity-score analysis

Context

Recent randomised controlled trials in Bangladesh and Kenya concluded that household water treatment, alone or in combination with upgraded sanitation and handwashing, did not reduce linear growth faltering or improve other child growth outcomes. Whether these results are applicable in areas with distinct constellations of water, sanitation and hygiene (WaSH) risks is unknown. Analysis of observational data offers an efficient means to assess the external validity of trial findings. We studied whether a water quality intervention could improve child growth in a rural Indian setting with higher levels of circulating pathogens than the original trial sites.

Methods

We analysed a cross-sectional dataset including a microbiological measure of household water quality. All households accessed water from an improved source. We applied propensity score methods to emulate a randomised trial investigating the hypothesis that receipt of drinking water meeting Sustainable Development Goal (SDG) 6.1 quality standards for absence of faecal contamination leads to improved growth. Growth outcomes (stunting, underweight, wasting, and their corresponding Z-scores) were assessed in children 12–23 months of age. For each outcome, we estimated the mean and 95% confidence interval of the absolute risk difference between treatment groups.

Findings

Of 1088 households, 442 (40.62%) received drinking water meeting SDG 6.1 standards. The adjusted risk of child underweight was 7.4% (1.3% to 13.4%) lower among those drinking water satisfying SDG 6.1 norms than among controls. Evidence concerning the relationship of drinking water meeting SDG 6.1 norms to length-for-age and weight-for-age was inconclusive, and there was no apparent relationship with stunting or wasting.

Conclusions

In contexts characterised by high pathogen transmission, water quality improvements have the potential to reduce the proportion of underweight children, but are unlikely to impact stunting or wasting. Further research is required to assess how these modelled benefits can best be achieved in real world settings.

Measuring and understanding social-emotional behaviors in preschoolers from rural Pakistan

The Strengths and Difficulties Questionnaire (SDQ) is widely-used to measure symptoms of common childhood behavioral problems that may lead to mental health difficulties. In a sample of 1,302 highly-disadvantaged mothers and their preschoolers, we evaluated the factor structure and reliability of the parent-report version of the SDQ in rural Pakistan. Confirmatory factor analyses suggested that the original structure of the SDQ was not appropriate for our data. We created conceptually- and empirically-coherent measures of children's externalizing behavior problems and prosocial skills. Child and family correlates of social-emotional behaviors were similar to those found in other countries, supporting the validity of our new composites. Girls and children with more siblings had fewer externalizing behavior problems and more prosocial behaviors at four years. Further, maternal depressive symptoms and food insecurity were uniquely linked to more externalizing behavior problems at four years. In contrast, maternal education, home environment quality, and social-emotional skills at two years were associated with more prosocial behaviors at four years.

Functional principal component analysis for identifying multivariate patterns and archetypes of growth, and their association with long-term cognitive development

For longitudinal studies with multivariate observations, we propose statistical methods to identify clusters of archetypal subjects by using techniques from functional data analysis and to relate longitudinal patterns to outcomes. We demonstrate how this approach can be applied to examine associations between multiple time-varying exposures and subsequent health outcomes, where the former are recorded sparsely and irregularly in time, with emphasis on the utility of multiple longitudinal observations in the framework of dimension reduction techniques. In applications to children’s growth data, we investigate archetypes of infant growth patterns and identify subgroups that are related to cognitive development in childhood. Specifically, “Stunting” and “Faltering” time-dynamic patterns of head circumference, body length and weight in the first 12 months are associated with lower levels of long-term cognitive development in comparison to “Generally Large” and “Catch-up” growth. Our findings provide evidence for the statistical association between multivariate growth patterns in infancy and long-term cognitive development.

Early development of visual attention in infants in rural Malawi

Eye tracking research has shown that infants develop a repertoire of attentional capacities during the first year. The majority of studies examining the early development of attention comes from Western, high-resource countries. We examined visual attention in a heterogeneous sample of infants in rural Malawi (N = 312-376, depending on analysis). Infants were assessed with eye-tracking-based tests that targeted visual orienting, anticipatory looking, and attention to faces at 7 and 9 months. Consistent with prior research, infants exhibited active visual search for salient visual targets, anticipatory saccades to predictable events, and a robust attentional bias for happy and fearful faces. Individual variations in these processes had low to moderate odd-even split-half and test-retest reliability. There were no consistent associations between attention measures and gestational age, nutritional status, or characteristics of the rearing environment (i.e., maternal cognition, psychosocial well-being, socioeconomic status, and care practices). The results replicate infants' early attentional biases in a large, unique sample, and suggest that some of these biases (e.g., bias for faces) are pronounced in low-resource settings. The results provided no evidence that the initial manifestation of infants' attentional capacities is associated with risk factors that are common in low-resource environments.

Modeling household transmission dynamics: Application to waterborne diarrheal disease in Central Africa

Introduction

We describe a method for analyzing the within-household network dynamics of a disease transmission. We apply it to analyze the occurrences of endemic diarrheal disease in Cameroon, Central Africa based on observational, cross-sectional data available from household health surveys.

Methods

To analyze the data, we apply formalism of the dynamic SID (susceptible-infected-diseased) process that describes the disease steady-state while adjusting for the household age-structure and environment contamination, such as water contamination. The SID transmission rates are estimated via MCMC method with the help of the so-called synthetic likelihood approach.

Results

The SID model is fitted to a dataset on diarrhea occurrence from 63 households in Cameroon. We show that the model allows for quantification of the effects of drinking water contamination on both transmission and recovery rates for household diarrheal disease occurrence as well as for estimation of the rate of silent (unobserved) infections.

Conclusions

The new estimation method appears capable of genuinely capturing the complex dynamics of disease transmission across various human, animal and environmental compartments at the household level. Our approach is quite general and can be used in other epidemiological settings where it is desirable to fit transmission rates using cross-sectional data.

Software sharing

The R-scripts for carrying out the computational analysis described in the paper are available at https://github.com/cbskust/SID.

Does early linear growth failure influence later school performance? A cohort study in Karonga district, northern Malawi

INTRODUCTION

Stunting or linear growth retardation in childhood is associated with delayed cognitive development due to related causes (malnutrition, illness, poor stimulation), which leads to poor school outcomes at later ages, although evidence of the association between the timing and persistence of stunting and school outcomes within the sub-Saharan African context is limited.

METHODS

Anthropometric data around birth (0-4 months), early (11-16 months) and late childhood (ages 4-8 years) along with school outcomes up until the age of 11 were analysed for a cohort of 1,044 respondents, born between 2002-2004 in Karonga district, northern Malawi. The schooling outcomes were age at school enrolment, grade repetition in Standard 1 and age-for-grade by age 11. Height-for-Age Z-scores (HAZ) and growth trajectories were examined as predictors, based on stunting (<-2SD HAZ) and on trajectories between early and late childhood (never stunted, improvers, decliners or persistently stunted). Multinomial and logistic regression were used to estimate the association between stunting/trajectories and schooling, adjusted for socioeconomic confounders.

RESULTS

The effects of stunting on schooling were evident in early childhood but were more pronounced in late childhood. Children who were stunted in early childhood (9.3%) were less likely to be underage at enrolment, more likely to repeat Standard 1 and were 2-3 times more likely to be overage for their grade by the age of 11, compared to their non-stunted peers. Those persistently stunted between early and late childhood (7.3%) faced the worst consequences on schooling, being three times as likely to enrol late and 3-5 times more likely to be overage for their grade by the age of 11, compared to those never stunted. Compared to improvers, those persistently stunted were three times as likely to be overage by two or more years by the age of 11, with no effect on enrolment or repetition.

CONCLUSION

Our findings confirm the importance of early childhood stunting on schooling outcomes and suggest some mitigation by improvements in growth by the age of starting school. The nutritional and learning needs of those persistently stunted may need to be prioritised in future interventions.

Linear Growth through 12 Years is Weakly but Consistently Associated with Language and Math Achievement Scores at Age 12 Years in 4 Low- or Middle-Income Countries

Background

Whether linear growth through age 12 y is associated with language and math achievement at age 12 y remains unclear.

Objective

Our objective was to investigate associations of linear growth through age 12 y with reading skill, receptive vocabulary, and mathematics performance at age 12 y in 4 low- or middle-income countries (LMICs).

Methods

We analyzed data from the Young Lives Younger Cohort study in Ethiopia (n = 1275), India (n = 1350), Peru (n = 1402), and Vietnam (n = 1594). Age 1, 5, 8, and 12 y height-for-age z scores (HAZ) were calculated. Language and math achievement at age 12 y was assessed with the use of country-specific adaptations of the Peabody Picture Vocabulary Test, the Early Grades Reading Assessment, and a mathematics test; all test scores were standardized by age within country. We used path analysis to examine associations of HAZ with achievement scores. Twelve models were examined at each age (3 tests across 4 countries).

Results

Mean HAZ in each country was <-1.00 at all ages. Overall, linear growth through age 12 y was associated with 0.4-3.4% of the variance in achievement scores. HAZ at 1 y was positively and significantly associated with the test score in 11 of the 12 models. This association was significantly mediated through HAZ at 5, 8, and 12 y in 9 of the models. HAZ at 5, 8, and 12 y was positively and significantly associated with test scores in 8, 8, and 6 models, respectively. These associations were mediated through HAZ at older ages in 6 of the HAZ at 5-y models and in 6 of the HAZ at 8-y models.

Conclusion

Child relative linear growth between ages 1 and 12 y was weakly but consistently associated with language and math achievement at age 12 y in 4 LMICs.

Prenatal nutrition, stimulation, and exposure to punishment are associated with early child motor, cognitive, language, and socioemotional development in Dar es Salaam, Tanzania

BACKGROUND

Despite growing evidence that early life experiences and exposures can impact child development, there is limited research on how prenatal and early life nutrition and early life parenting practices predict specific domains of child development in resource-limited settings. This study examines the association between prenatal factors, birth outcomes, and early life characteristics with motor, cognitive/language, and socioemotional development in Tanzania.

METHODS

We assessed motor, cognitive/language, and socioemotional development among a cohort of 198 children aged 20-39 months in Dar es Salaam, Tanzania, whose mothers were previously enrolled in a randomized, placebo-controlled trial of prenatal vitamin A and zinc supplementation. Linear regression models were used to assess standardized mean differences in child development scores for randomized prenatal regimen and pregnancy, delivery, and early childhood factors.

RESULTS

Children born to mothers randomized to prenatal vitamin A had significantly lower reported motor scores in minimally adjusted and multivariate analyses, -0.29 SD, 95% CI [-0.54, -0.04], p = 0.03, as compared with children whose mothers did not receive vitamin A. There was no significant effect of randomized prenatal zinc on any development domain. Greater caregiver-child stimulation was associated with 0.38 SD, 95% CI [0.14, 0.63], p < 0.01, better cognitive/language scores, whereas children who experienced both verbal and physical punishment had 0.29 SD, 95% CI [-0.52, -0.05], p = 0.02, lower scores in socioemotional development. Maternal completion of primary school was associated with higher reported motor and cognitive/language development. Further, children of mothers who were <155 cm tall had lower cognitive and language scores.

CONCLUSION

Prenatal vitamin A supplements in a setting with low levels of vitamin A deficiency may not provide child development benefits. However, integrated environmental, educational, parenting, and stimulation interventions may have large positive effects across child development domains in resource-limited settings.

Measuring human capital: a systematic analysis of 195 countries and territories, 1990-2016

BACKGROUND

Human capital is recognised as the level of education and health in a population and is considered an important determinant of economic growth. The World Bank has called for measurement and annual reporting of human capital to track and motivate investments in health and education and enhance productivity. We aim to provide a new comprehensive measure of human capital across countries globally.

METHODS

We generated a period measure of expected human capital, defined for each birth cohort as the expected years lived from age 20 to 64 years and adjusted for educational attainment, learning or education quality, and functional health status using rates specific to each time period, age, and sex for 195 countries from 1990 to 2016. We estimated educational attainment using 2522 censuses and household surveys; we based learning estimates on 1894 tests among school-aged children; and we based functional health status on the prevalence of seven health conditions, which were taken from the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016). Mortality rates specific to location, age, and sex were also taken from GBD 2016.

FINDINGS

In 2016, Finland had the highest level of expected human capital of 28·4 health, education, and learning-adjusted expected years lived between age 20 and 64 years (95% uncertainty interval 27·5-29·2); Niger had the lowest expected human capital of less than 1·6 years (0·98-2·6). In 2016, 44 countries had already achieved more than 20 years of expected human capital; 68 countries had expected human capital of less than 10 years. Of 195 countries, the ten most populous countries in 2016 for expected human capital were ranked: China at 44, India at 158, USA at 27, Indonesia at 131, Brazil at 71, Pakistan at 164, Nigeria at 171, Bangladesh at 161, Russia at 49, and Mexico at 104. Assessment of change in expected human capital from 1990 to 2016 shows marked variation from less than 2 years of progress in 18 countries to more than 5 years of progress in 35 countries. Larger improvements in expected human capital appear to be associated with faster economic growth. The top quartile of countries in terms of absolute change in human capital from 1990 to 2016 had a median annualised growth in gross domestic product of 2·60% (IQR 1·85-3·69) compared with 1·45% (0·18-2·19) for countries in the bottom quartile.

INTERPRETATION

Countries vary widely in the rate of human capital formation. Monitoring the production of human capital can facilitate a mechanism to hold governments and donors accountable for investments in health and education.

FUNDING

Institute for Health Metrics and Evaluation.

Growth and body composition of children aged 2-4 years after exposure to community mobilisation women's groups in Bangladesh

BACKGROUND

Women's groups interventions in Bangladesh reduced neonatal deaths by 38% and improved hygienic delivery, newborn care practices and breast feeding. We explore the longer-term impact of exposure to women's groups during pregnancy on child growth at 2-4 years.

METHODS

We performed a cross-sectional survey of child anthropometric measures (analysed as z-scores) among children born to women who had participated in the women's groups interventions while pregnant, compared with an age-matched and sex-matched sample of children born to control mothers. Results were stratified by maternal body mass index (BMI) and adjusted for possible confounding effects of maternal education, household asset ownership and, in a separate model, mother-child height difference, a proxy for improved survival of small babies in intervention groups.

RESULTS

Data were obtained from 2587 mother-child pairs (91% response). After adjustment for asset ownership, maternal education and potential survival effects, children whose mothers were exposed to the women's group intervention had higher head (0.16 (0.04 to 0.28)), mid-upper arm (0.11 (0.04 to 0.19)), abdominal (0.13 (0.00 to 0.26)) and chest (0.18 (0.08 to 0.29)) circumferences than their control counterparts. No significant differences in subcutaneous fat (subscapular and triceps skinfold thickness) were observed. When stratified by maternal BMI, intervention children had higher weight, BMI and circumferences, and these effects decreased with increasing maternal BMI category.

CONCLUSIONS

Women's groups appear to have had a lasting, positive impact on child anthropometric outcomes, with most significant results clustering in children of underweight mothers. Observed differences are likely to be of public health significance in terms of the nutritional and metabolic development of children.

Description of Child and Adolescent Beverage and Anthropometric Measures According to Adolescent Beverage Patterns

Our objective is to retrospectively describe longitudinal beverage intakes and anthropometric measures according to adolescent beverage patterns. Data were collected from Iowa Fluoride Study participants (n = 369) using beverage questionnaires at ages 2⁻17 years. Weight and height were measured at ages 5, 9, 13 and 17 years. Cluster analyses were used to identify age 13- to 17-year beverage patterns. Treating age and beverage cluster as explanatory factors, sex-specific generalized linear mixed models were used to identify when differences in beverage intakes and anthropometric measures began. Predominant beverage intakes were higher in each of the corresponding clusters by 9⁻12.5 years; females with high milk intakes during adolescence and males with high 100% juice or sugar-sweetened beverage intakes during adolescence reported higher intakes of that beverage beginning at 2⁻4.7 years. Females and males in the 100% juice cluster had lower weights than other clusters beginning at 13 years, while females and males in the neutral cluster were shorter beginning at 13 years. Females in the water/sugar-free beverage cluster had higher body mass indices (BMIs) beginning at 9 years. Females and males in the 100% juice cluster had lower BMIs beginning at 5 and 9 years, respectively. Childhood beverage intakes and growth patterns differ according to adolescent beverage patterns.

Acceptability and Reliability of the Bayley Scales of Infant and Toddler Development-III Among Children in Bhaktapur, Nepal

Background: The Bayley Scales of Infant and Toddler Development, 3rd edition (Bayley-III) is the most widely used developmental assessment tool for infants and toddlers worldwide, but less is known about its psychometric properties and feasibility in low and middle-income countries. Aim: To assess the psychometric properties and feasibility of the Bayley-III when used in a large scale randomized controlled intervention trial in Nepal. Methods: The participating infants were part of a randomized, doubled blind, placebo-controlled trial to measure the efficacy of vitamin B12 supplementation on growth and neurodevelopment. A total of 600 children aged 6-11 months were enrolled and included for developmental assessment. The Bayley-III measures child development across five domains: cognition, receptive and expressive language, fine and gross motor skills. Some items were culturally adapted. To measure and ensure appropriate inter-observer agreement, standardization exercises were performed during the initial training, and double scoring of 7% of test sessions were conducted throughout the study by two examiners. Results: The inter-rater agreement was excellent for both the standardization exercises before the start of the study, and for the quality control throughout the study with intraclass correlation coefficient ranging from 0.95 to 0.99. The internal consistency measured by the Cronbach's alpha coefficient ranged between 0.57 and 0.87. The subtests raw scores as well as scaled scores were significantly correlated (p < 0.001). The means and SDs of the scaled scores compared with American norms were similar to the distribution in the American sample, with the exception of the receptive (Mean = 7.7, SD = 2.2) and expressive (Mean = 7.3, SD = 1.9) language subtests that were lower than the American norms. Conclusion: The inter-rater reliability between the scorers on the Bayley-III was excellent both during standardization and for the quality control. The distributions for the cognitive and motor subscales are comparable to the American norms, while caution is needed in the interpretation of the language scales. The results suggest that Bayley-III is a feasible tool for the assessment of neurodevelopmental status in nutritional studies in low resource settings such as Nepal. Cultural adaptations, training and standardization are prerequisites for a valid and reliable assessment using the Bayley-III.

Intimate Partner Violence, Depression, and Child Growth and Development

BACKGROUND

Evidence on the relationship between maternal depression and exposure to intimate partner violence (IPV) with child physical growth and development is equivocal. Our aim in the current study is to examine these relationships among women and their children in Tanzania.

METHODS

The Bayley Scales of Infant Development and anthropometric measures were used to assess children 18 to 36 months of age (n = 1031). Maternal exposure to IPV and depression were assessed using the Tanzania Demographic and Health Survey questionnaire and the Patient Health Questionnaire-9, respectively. We used linear regression models to calculate standardized mean differences (SMDs) for developmental outcomes and generalized linear models to estimate the associations with nutritional status.

RESULTS

Mild depressive symptoms in mothers (Patient Health Questionnaire-9 ≥5) and exposure to physical and sexual IPV were associated with lower SMDs for motor skills (-0.14 [P = .023] and -0.23 [P < .01], respectively), expressive communication (-0.13 [P = .187] and -0.23 [P < .01], respectively), receptive communication (-0.19 [P < .009] and -0.16 [P = .03], respectively), and cognitive development (-0.08 [P = .245] and -0.12 [P = .07], respectively). Exposure to physical and sexual IPV was associated with higher risk for stunting (relative risk = 1.6; P < .001).

CONCLUSIONS

This study reveals that maternal depressive symptoms and IPV are associated with adverse child nutritional and developmental outcomes. Further research is needed to develop programs to address IPV and depression among women and enhance the growth and development of their children.

Higher Longitudinal Milk Intakes Are Associated with Increased Height in a Birth Cohort Followed for 17 Years

Background

Height is an indicator of nutritional status; linear growth faltering has recognized consequences for cognitive, emotional, and chronic disease risk. Although height is routinely studied in developing countries, less attention is given to height in the United States.

Objective

The objective of this study was to identify longitudinal associations between childhood and adolescent beverage intakes, nutrient adequacy, or energy intake and height in a birth cohort.

Methods

Data for participants through ages 2-17 y (n = 717; 353 males, 364 females) recruited at birth for the longitudinal Iowa Fluoride Study (IFS) were used in the current cohort analyses. Beverage intakes (n = 708) were collected by beverage-frequency questionnaires at 3- to 6-mo intervals, whereas nutrient data (n = 652) were obtained from 3-d food diaries completed at 3- to 6-mo intervals through age 8.5 y and from Block Kids' food-frequency questionnaires at 2-y intervals after age 8.5 y. Nutrient adequacy ratios were calculated with the use of age- and sex-specific Estimated Average Requirements. Height was measured at clinic visits when the participants were approximately ages 5, 9, 11, 13, 15, and 17 y. Linear mixed models were used to identify longitudinal associations between dietary variables and height. A baseline model that adjusted for changing growth patterns during adolescence was established. Dietary and potential confounding variables were added to this baseline model.

Results

Milk intake adjusted for mean adequacy ratio, energy intake, and baseline socioeconomic status was associated with height; for each additional 8 ounces (236 mL) of milk consumed per day throughout childhood and adolescence, height increased, on average, by 0.39 cm (95% CI: 0.18, 0.60 cm; P < 0.001).

Conclusions

IFS participants' height increased by 0.39 cm for each additional 8 ounces (236 mL) of milk consumed throughout childhood and adolescence. The clinical implications of the mild linear growth faltering observed in healthy youth are unknown. This trial was registered at www.clinicaltrials.gov as 199112665.