Antenatal and early infant predictors of postnatal growth in rural Vietnam: a prospective cohort study

Prevalence, determinants, intervention strategies and current gaps in addressing childhood malnutrition in Vietnam: a systematic review

BACKGROUND

Childhood malnutrition in all forms is a major public health issue worldwide. This review systematically examined the prevalence and determinants and identify the potential interventions and current gap in addressing malnutrition including undernutrition, overnutrition and micronutrient deficiencies (MNDs) in Vietnamese children aged 0-18 years old.

METHODS

Embase, Scopus, PubMed, and Web of Science were systematically searched through June 2022 to identify relevant articles published within the past 25 years. Study selection and data extraction were performed by one reviewer and checked for accuracy by the other two reviewers in accordance with PRISMA guideline. Risk of publication bias was assessed using American Dietetic Association Quality Criteria Checklist.

RESULTS

Seventy-two studies that met the inclusion criteria were included. Undernutrition has decreased over time but still 22.4%, 5.2% and 12.2% of children under 5 were stunted, wasted and underweight, respectively. Anaemia, iron, zinc, and vitamin D deficiencies were the more common forms of MNDs, the prevalence varied by age, region, and socioeconomic group. Population-based surveys reported that 11% and 48% of children aged 0-11 years old were iron and vitamin D deficient, respectively. Zinc deficiency affected almost one-quarter of the children and adolescents. Retinol deficiency was of less concern (< 20%). However, more evidence on MNDs prevalence is needed. Overweight and obesity is now on the rise, affecting one-third of school-aged children. The key determinants of undernutrition included living in rural areas, children with low birth weight, and poor socio-economic status, whereas living in urban and affluent areas, having an inactive lifestyle and being a boy were associated with increased risk of overweight and obesity. Nutrition specific intervention studies including supplementation and food fortification consistently showed improvements in anthropometric indices and micronutrient biomarkers. National nutrition-sensitive programmes also provided nutritional benefits for children's growth and eating behaviours, but there is a lack of data on childhood obesity.

CONCLUSION

This finding highlights the need for effective double duty actions to simultaneously address different forms of childhood malnutrition in Vietnam. However, evidence on the potential intervention strategies, especially on MNDs and overnutrition are still limited to inform policy decision, thus future research is warranted.

Maternal socioeconomic status and infant feeding practices underlying pathways to child stunting in Cambodia: structural path analysis using cross-sectional population data

OBJECTIVES

To identify and investigate complex pathways to stunting among children aged 6-24 months to determine the mediating effects of dietary diversity and continued breast feeding on the association between socioeconomic factors and child stunting.

DESIGN, SETTING AND PARTICIPANTS

We analysed the most recent cross-sectional Demographic and Health Survey data from Cambodia (2014). We applied structural path analysis on a sample of 1365 children to model the complex and inter-related pathways of factors determining children's height for age. Explanatory variables included a composite indicator of maternal employment, household wealth, maternal education, current breastfeeding status and dietary diversity score. Results are presented both in terms of non-standardised and standardised coefficients.

OUTCOME MEASURE

The primary outcome measure was height-for-age Z-scores as a continuous measure.

RESULTS

Findings suggest that children's dietary diversity and continued breast feeding mediate the association between socioeconomic status and children's height. While there was no significant direct effect of maternal education on children's height, results suggested significant indirect pathways through which maternal education effects children's height; operating through household wealth, maternal employment, dietary diversity and continued breastfeeding status (p&lt;0.001). Most notably, 41% of the effect of maternal employment on children's height was mediated by either dietary diversity or continued breast feeding.

CONCLUSION

We provide evidence to support targeted nutrition interventions which account for the different ways in which underlying socioeconomic factors influence infant and young child feeding practices, and the potential impact on child nutritional status.

Umbilical cord serum elementomics of 52 trace elements and early childhood neurodevelopment: Evidence from a prospective birth cohort in rural Bangladesh

BACKGROUND

Prenatal exposures to neurotoxic metals and trace elements are associated with early childhood neurodevelopmental outcomes. However, consequences of simultaneous exposure to mixtures of elements remain unclear.

OBJECTIVE

To examine individual and joint effects of prenatal trace element exposure on early childhood neurodevelopment.

METHODS

Using a well-established Bangladesh prospective birth cohort (2008-2011), we measured concentrations of 52 trace elements in umbilical cord serum of 569 mother-infant pairs using inductively coupled plasma mass spectrometry. Neurodevelopment was evaluated at 20-40 months of age using Bayley Scales of Infant and Toddler Development, Third Edition. Stability elastic net (ENET) was used to screen elements individually associated with the outcome; candidate exposures were combined by weighted linear combination to form a risk score representing their mixture effect on early childhood neurodevelopment.

RESULTS

Stability ENET identified 15 trace elements associated with cognitive composite score and 14 associated with motor composite score, which were linearly combined to form the element risk score (ERS). Children with higher ERScognitive had lower probability of cognitive developmental delay (ORhighest vs lowest: 0.21; 95 %CI: 0.10, 0.40; P < 0.001; Ptrend < 0.001). Children with ERSmotor in the top quintile had a significantly lower risk of motor developmental delay (OR: 0.16; 95 %CI: 0.09, 0.31; P < 0.001; Ptrend < 0.001) versus the lowest quintile. In Bayesian kernel machine regression analyses, lithium [conditional posterior inclusion probability (cPIP) = 0.68], aluminum (cPIP = 0.83) and iron (cPIP = 1.00) contributed most to the lower cognitive composite score; zinc (cPIP = 1.00), silver (cPIP = 0.81), and antimony (cPIP = 0.65) mainly contributed to the change of motor composite score.

CONCLUSION

Co-exposure to lithium/aluminum/iron or zinc/silver/antimony appears to impact children's neurodevelopment. ERS score reflecting maternal exposure could indicate children's risk of neurodevelopmental delay, warranting further studies to explore the underlying mechanism.

Materno-fetal iron transfer and the emerging role of ferroptosis pathways

A successful pregnancy and the birth of a healthy baby depend to a great extent on the controlled supply of essential nutrients via the placenta. Iron is essential for mitochondrial energy supply and oxygen distribution via the blood. However, its high reactivity requires tightly regulated transport processes. Disturbances of maternal-fetal iron transfer during pregnancy can aggravate or lead to severe pathological consequences for the mother and the fetus with lifelong effects. Furthermore, high intracellular iron levels due to disturbed gestational iron homeostasis have recently been associated with the non-apoptotic cell death pathway called ferroptosis. Therefore, the investigation of transplacental iron transport mechanisms, their physiological regulation and potential risks are of high clinical importance. The present review summarizes the current knowledge on principles and regulatory mechanisms underlying materno-fetal iron transport and gives insight into common pregnancy conditions in which iron homeostasis is disturbed. Moreover, the significance of the newly emerging ferroptosis pathway and its impact on the regulation of placental iron homeostasis, oxidative stress and gestational diseases will be discussed.

Child linear growth trajectories during the first three years of life in relation to infant iron status: a prospective cohort study in rural Vietnam

Background

Early childhood growth patterns have long-term consequences for health and disease. Little is known about the interplay between growth and iron status during childhood. We explored the interplay between linear growth and iron status during early childhood, by assessing child growth trajectories between 6 and 36 months (m) of age in relation to infant iron status at 6 months of age.

Methods

A cohort study of infants born to women who had previously participated in a cluster randomized controlled trial of antenatal micronutrient supplementation, conducted in rural Vietnam. The relationship between child linear growth trajectories and infant iron status (ferritin concentration) was examined using latent growth curve modeling. Primary outcomes were height for age z scores (HAZ) and growth trajectory between 6 and 36 m of age.

Results

A total of 1112 infants were included in the study. Mean [SD] HAZ scores decreased over time from –0·58 [0·94] at 6 m, to –0·97 [0·99] at 18 m, to –1·14 [0·89] at 36 m of age. There was a steep linear decline in the HAZ scores between 6 and 18 m of age, followed by a slower linear decline from 18 to 36 m of age. Ferritin concentration at 6 m of age was inversely associated with HAZ score at 6 m of age (-0·145, 95% CI [-0.189, -0.101]). There was no association between infant ferritin at 6 m of age and child growth trajectory between 6 and 36 m of age.

Conclusions

Iron status at six months of age did not influence a child’s later linear growth trajectory in this cohort of rural Vietnamese children. Longitudinal studies with repeated ferritin and height measurements are required to better delineate this relationship and inform public health interventions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40795-022-00505-y.

Maternal Iron Status in Pregnancy and Child Health Outcomes after Birth: A Systematic Review and Meta-Analysis

In pregnancy, iron deficiency and iron overload increase the risk for adverse pregnancy outcomes, but the effects of maternal iron status on long-term child health are poorly understood. The aim of the study was to systematically review and analyze the literature on maternal iron status in pregnancy and long-term outcomes in the offspring after birth. We report a systematic review on maternal iron status during pregnancy in relation to child health outcomes after birth, from database inception until 21 January 2021, with methodological quality rating (Newcastle-Ottawa tool) and random-effect meta-analysis. (PROSPERO, CRD42020162202). The search identified 8139 studies, of which 44 were included, describing 12,7849 mother–child pairs. Heterogeneity amongst the studies was strong. Methodological quality was predominantly moderate to high. Iron status was measured usually late in pregnancy. The majority of studies compared categories based on maternal ferritin, however, definitions of iron deficiency differed across studies. The follow-up period was predominantly limited to infancy. Fifteen studies reported outcomes on child iron status or hemoglobin, 20 on neurodevelopmental outcomes, and the remainder on a variety of other outcomes. In half of the studies, low maternal iron status or iron deficiency was associated with adverse outcomes in children. Meta-analyses showed an association of maternal ferritin with child soluble transferrin receptor concentrations, though child ferritin, transferrin saturation, or hemoglobin values showed no consistent association. Studies on maternal iron status above normal, or iron excess, suggest deleterious effects on infant growth, cognition, and childhood Type 1 diabetes. Maternal iron status in pregnancy was not consistently associated with child iron status after birth. The very heterogeneous set of studies suggests detrimental effects of iron deficiency, and possibly also of overload, on other outcomes including child neurodevelopment. Studies are needed to determine clinically meaningful definitions of iron deficiency and overload in pregnancy.

Co-morbid anaemia and stunting among children of pre-school age in low- and middle-income countries: a syndemic

OBJECTIVE

To determine the prevalence of co-morbidity of two important global health challenges, anaemia and stunting, among children aged 6-59 months in low- and middle-income countries.

DESIGN

Secondary analysis of data from Demographic and Health Surveys (DHS) conducted 2005-2015. Child stunting and anaemia were defined using current WHO classifications. Sociodemographic characteristics of children with anaemia, stunting and co-morbidity of these conditions were compared with those of 'healthy' children in the sample (children who were not stunted and not anaemic) using multiple logistic models.

SETTING

Low- and middle-income countries.

SUBJECTS

Children aged 6-59 months.

RESULTS

Data from 193 065 children from forty-three countries were included. The pooled proportion of co-morbid anaemia and stunting was 21·5 (95 % CI 21·2, 21·9) %, ranging from the lowest in Albania (2·6 %; 95 % CI 1·8, 3·7 %) to the highest in Yemen (43·3; 95 % CI 40·6, 46·1 %). Compared with the healthy group, children with co-morbidity were more likely to be living in rural areas, have mothers or main carers with lower educational levels and to live in poorer households. Inequality in children who had both anaemia and stunting was apparent in all countries.

CONCLUSIONS

Co-morbid anaemia and stunting among young children is highly prevalent in low- and middle-income countries, especially among more disadvantaged children. It is suggested that they be considered under a syndemic framework, the Childhood Anaemia and Stunting (CHAS) Syndemic, which acknowledges the interacting nature of these diseases and the social and environmental factors that promote their negative interaction.

Prevalence and determinants of stunting in a conflict-ridden border region in Armenia - a cross-sectional study

BACKGROUND

Despite global efforts, stunting remains a public health problem in several developing countries. The prevalence of stunting among 0- to 5-year-old children in Armenia has increased from 17% in 2000 to 19% in 2010. A baseline study was conducted among preschool children in Berd, a region near the northeastern border of Armenia that has experienced intermittent military tension for over 20 years.

METHODS

We conducted a cross-sectional study including 594 children aged 6-month- 6 years old and their caregivers in our analysis, to assess the prevalence and determinants of stunting. We calculated the anthropometric measurements and hemoglobin levels of children; analyzed children's stool and conducted a survey with children's caregivers. We employed the hierarchical logistic regression model to explore the predictors of stunting among 25-72 months old children and multivariable logistic regression models to investigate the predictors of stunting among 6-24 months old children. Individual and residence level variables were included in the models including anemia, minimum dietary diversity, mothers' height, the overall duration of breastfeeding, birthweight, child's history of diarrhea and mean socio-economic score.

RESULTS

The prevalence of stunting was significantly higher among the 6-24 months old children (13.3%) compared to the children aged 25-72 months old (7.8%). We did not find any differences in the prevalence of stunting by place of residence in either age group. The 6-24 months old children who consumed at least four food groups during the previous day (minimum dietary diversity) had 72% lower odds of being stunted (p < 0.05). Each kilogram increase in birthweight was associated with 76% lower odds of being stunted (OR = 0.24, p < 0.01). Mother's height significantly decreased the odds of stunting among the children 25-72- months old (OR = 0.86, p < 0.001). BMI was also a significant predictor of stunting among both age-groups.

CONCLUSIONS

The study results highlight the significance of mother's height, birthweight, and adequate complementary feeding to reduce stunting. Further studies are needed to determine the possible association of anemia and stunting with the ongoing conflict in the region, as well as socioeconomic conditions and food insecurity in the region.

Cohort profile: maternal lifestyle and diet in relation to pregnancy, postpartum and infant health outcomes in Vietnam: A multicentre prospective cohort study

PURPOSE

To determine modifiable maternal risk factors for adverse pregnancy, postpartum maternal and child health outcomes in Vietnam.

PARTICIPANTS

This prospective cohort study included pregnant women seeking prenatal care at six hospitals in three large cities in Vietnam. After enrolment, eligible participants who gave their consent to participate in the study were interviewed at 24-28 weeks' gestation. Glucose testing was conducted and blood pressure was measured during this period. Each participant will be assessed prospectively during their postnatal visits at delivery, 1, 3, 6, 12, 18 and 24 months, and will be followed up for 5 years.

FINDINGS TO DATE

Of 2248 eligible pregnant women, 2030 were recruited (participation rate 90.3%) between August 2015 and July 2016. All participants completed the baseline assessment. Their mean (SD) age was 27.6 (5.3) years. The mean pre-pregnancy body mass index (BMI) was 20.2 (SD 2.6) kg/m², with nearly two-thirds of participants having a normal pre-pregnancy BMI (18.5 to <23.0 kg/m²) and one-quarter being underweight (pre-pregnancy BMI <18.5 kg/m²). Overweight or obese mothers (pre-pregnancy BMI ≥23.0 kg/m²) accounted for 12.8%. No pregnant women reported smoking during their pregnancy while 13.4% of them had continued drinking. 22.8% of participants had hyperglycaemia. Their mean systolic blood pressure was 105.6 (SD 8.2) mm Hg, and diastolic blood pressure was 67.4 (SD 7.5) mm Hg.

FUTURE PLANS

The relationships of maternal lifestyle and nutritional status with the health outcomes of pregnancy, postpartum maternity and infants will be analysed. Meanwhile, participants will be closely tracked to minimise loss to follow-up.

Body composition at birth and height at 2 years: a prospective cohort study among children in Jimma, Ethiopia

BACKGROUNDLow birth weight is associated with childhood stunting, but equivalent associations for birth body composition (BC) remain unknown. The aim of this study was to assess associations between birth BC and height-for-age z-score (HAZ) at 2 years of age.METHODSIn a prospective cohort study, fat mass (FM) and fat-free mass (FFM) were measured using air-displacement plethysmography within 48 h of birth. Linear regression models were applied to study the relationship between BC at birth and HAZ at 24 ±3 months.RESULTSA total of 268 children with height assessment at 2 years were included. Mean±SD HAZ at 2 years of age was -1.2±1.2, with 25.8% classified as stunted (HAZ <-2SD). FFM at birth was positively associated with HAZ at 2 years, independent of length at birth. When adjusted for potential confounders, HAZ at 2 years was 0.73 higher for each additional kg FFM at birth (β=0.73, 95% CI: 0.08, 1.38). FM was not associated with HAZ at 2 years in any model.CONCLUSIONThe FFM component of birth weight, independent of length at birth, explained variability in HAZ at 2 years. Further studies are required to explore how changes in early infant BC are associated with linear growth.

Maternal vitamin D supplementation during pregnancy and lactation to promote infant growth in Dhaka, Bangladesh (MDIG trial): study protocol for a randomized controlled trial

Background

Vitamin D regulates bone mineral metabolism and skeletal development. Some observational studies have suggested that prenatal vitamin D deficiency increases the risk of adverse pregnancy and/or birth outcomes; however, there is scant evidence from controlled trials, leading the World Health Organization to advise against routine vitamin D supplementation in pregnancy. Importantly, little is known about the effect of maternal vitamin D status on infant linear growth in communities in South Asia where stunting is highly prevalent and maternal-infant vitamin D status is commonly suboptimal.

Methods/Design

The Maternal Vitamin D for Infant Growth study is a randomized, placebo-controlled, dose-ranging trial of maternal vitamin D supplementation during pregnancy and lactation in Dhaka, Bangladesh. The primary aims are to estimate (1) the effect of maternal prenatal oral vitamin D₃ supplementation (4200 IU/wk, 16,800 IU/wk, or 28,000 IU/wk, administered as weekly doses) versus placebo on infant length at 1 year of age and (2) the effect of maternal postpartum oral vitamin D₃ supplementation (28,000 IU/wk) versus placebo on length at 1 year of age among infants born to women who received vitamin D 28,000 IU/wk during pregnancy. Generally healthy pregnant women (n = 1300) in the second trimester (17–24 weeks of gestation) are randomized to one of five parallel arms: placebo 4200 IU/wk, 16,800 IU/wk, or 28,000 IU/wk in the prenatal period and placebo in the postpartum period or 28,000 IU/wk in the prenatal period and 28,000 IU/wk in the postpartum period. Household- and clinic-based follow-up of mother-infant pairs is conducted weekly by trained personnel until 26 weeks postpartum and every 3 months thereafter. The primary trial outcome measure is length for age z-score at 1 year of age. Anthropometric measurements, clinical information, and biological specimens collected at scheduled intervals will enable the assessment of a range of maternal, perinatal, and infant outcomes.

Discussion

The role of vitamin D in maternal and infant health remains unresolved. This trial is expected to contribute unique insights into the effects of improving maternal-infant vitamin D status in a low-income setting where stunting and adverse perinatal outcomes represent significant public health burdens.

Trial registration

ClinicalTrials.gov identifier: NCT01924013. Registered on 13 August 2013

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-015-0825-8) contains supplementary material, which is available to authorized users.