Risk factors associated with malnutrition in one-year-old children living in the Peruvian Amazon

Decreased Weight-for-Age Associated with Mass Deworming among Young Ethiopian Schoolchildren in Jimma Town, Southwest Ethiopia: A School-Based Cross-Sectional Study

School-based mass deworming programs are implemented to reduce soil-transmitted helminth (STH) infection prevalence and intensity among school-aged children. However, previous studies debate the impact of deworming beyond the removal of worms. Hence, this study aimed to examine the effect of mass deworming on nutritional indicators in young Ethiopian schoolchildren. A school-based cross-sectional study was conducted among 1,036 participants from April to May 2020 in Jimma Town, Ethiopia. An interviewer-based questionnaire was administered to the children to gather data on sociodemographic, lifestyle variables, and deworming status. Anthropometric measurements were taken for the height and weight of the children. Stool samples were collected and analyzed for STH infection using direct wet mount microscopy and the Kato-Katz technique. In multivariate logistic regression analysis, deworming within the past 6 months or 1 year was not significantly associated with underweight, stunting, and thinning. However, deworming within the past year was significantly associated with decreased weight-for-age z-score (adjusted mean difference = -0.245; 95% CI: -0.413 to -0.076; P = 0.004). Deworming in the past 6 months demonstrated a nonsignificant trend toward increased stunting (adjusted odds ratio = 1.258; 95% CI: 0.923-1.714; P = 0.145). This study provides evidence that deworming in the past 6 months or 1 year was not significantly associated with underweight, stunting, and thinning. However, deworming within the past year was associated with a significantly decreased weight-for-age z-score in young Ethiopian schoolchildren of Jimma Town after adjustment for confounding variables.

Impact of helminth-microbiome interactions on childhood health and development-A clinical perspective

Humans have co-existed with parasites for virtually the entirety of our existence as a species. Today, nearly one third of the human population is infected with at least one helminthic species, most of which reside in the intestinal tract, where they have co-evolved alongside the human gut microbiota (GM). Appreciation for the interconnected relationship between helminths and GM has increased in recent years. Here, we review the evidence of how helminths and GM can influence various aspects of childhood development and the onset of paediatric diseases. We discuss the emerging evidence of how many of the changes that parasitic worms inflict on their host is enacted through gut microbes. In this light, we argue that helminth-induced microbiota modifications are of great importance in both facing the global challenge of overcoming parasitic infections, and in replicating helminthic protective effects against inflammatory diseases. We propose that deepening our knowledge of helminth-microbiota interactions will uncover novel, safer and more effective therapeutic strategies in combatting an array of childhood disorders.

Stunting as a Risk Factor of Soil-Transmitted Helminthiasis in Children: A Literature Review

As a high-burden neglected tropical disease, soil-transmitted helminth (STH) infections remain a major problem in the world, especially among children under five years of age. Since young children are at high risk of being infected, STH infection can have a long-term negative impact on their life, including impaired growth and development. Stunting, a form of malnutrition in young children, has been long assumed as one of the risk factors in acquiring the STH infections. However, the studies on STH infection in children under five with stunting have been lacking, resulting in poor identification of the risk. Accordingly, we collected and reviewed existing related research articles to provide an overview of STH infection in a susceptible population of stunted children under five years of age in terms of prevalence and risk factors. There were 17 studies included in this review related to infection with Ascaris lumbricoides, Trichuris trichiura, hookworm, and Strongyloides stercoralis from various countries. The prevalence of STH infection in stunted children ranged from 12.5% to 56.5%. Increased inflammatory markers and intestinal microbiota dysbiosis might have increased the intensity of STH infection in stunted children that caused impairment in the immune system. While the age from 2 to 5 years along with poor hygiene and sanitation has shown to be the most common risk factors of STH infections in stunted children; currently there are no studies that show direct results of stunting as a risk factor for STH infection. While stunting itself may affect the pathogenesis of STH infection, further research on stunting as a risk factor for STH infection is encouraged.

Associated factors of the co-occurrence of trachoma and soil-transmitted helminthiases in children 1 to 9 years old in rural communities of the Amazon basin in Loreto Department, Peru: Results from a population-based survey

BACKGROUND

There is evidence of the occurrence of trachoma in Peru, and studies have shown that soil-transmitted helminthiases (STH) are affecting rural communities in the Amazon basin in Loreto Department. This study was done to estimate trachoma prevalence, STH prevalence, and the associated factors for both diseases in children aged 1-9 years in rural communities of Peru.

METHODOLOGY

A population-based cross-sectional survey was carried out in rural communities of Loreto. A standardized survey questionnaire with individual and household risk factors related to both diseases was used. Ocular examination was done for all participants aged one year and above, and eye swab samples were collected from children with follicular trachoma (TF). Anthropometric measurements, stool samples for STH, and blood samples for hemoglobin measurement were taken from children.

PRINCIPAL FINDINGS

TF prevalence was 7.74% (95% CI 5.08-11.63%), STH prevalence was 49.49% (95% CI 25.00-52.43%), and prevalence of co-occurrence of both diseases was 5.06% (95% CI 2.80-8.98%) in children aged 1-9 years. Being at age 3-8 years old (AOR = 6.76; 95% CI 1.346-33.947), have an unclean face (AOR = 24.64; 95% CI 6.787-89.444), and having been dewormed in the last six months (AOR = 2.47; 95% CI 1.106-5.514), were risk factors of TF. Being a female (AOR = 0.22; 95% CI 0.103-0.457) was associated with decreased odds of TF. Having been dewormed in the last six months (AOR = 0.30; 95% CI 0.139-0.628) was a preventative factor for STH. Risk factors for children with both diseases mirrored the findings for risk factors for individual diseases.

CONCLUSIONS

Neglected tropical diseases and associated risk factors overlap in communities living in vulnerable conditions in the Amazon basin of Peru. These findings support the need to implement integrated interventions, including mass drug administration, water, sanitation, and hygiene for both diseases in the study area.

Prevalence of malnutrition, anemia, and soil-transmitted helminthiasis in preschool-age children living in peri-urban populations in the Peruvian Amazon

Stunting, anemia, and soil-transmitted helminth (STH) infections are major health concerns for children in extremely poor regions of the world, especially rural and periurban ones. This study aimed to determine the prevalence of these three cooccurring conditions in preschool-age children in an extremely poor district on the outskirts of Iquitos, in the Peruvian Amazon, to inform public health actions. Malnutrition was assessed by standard World Health Organization-recommended metrics; anemia, by hemoglobin levels; and STH, by the Kato-Katz technique. Logistic regression analyses were performed to identify the risk factors for our three outcomes of interest. A total of 572 children aged 6-59 months were recruited in March 2019. We found a 31.3% stunting, 47.2% anemia, and 34.1% STH prevalence. Stunting and anemia figures exceeded both regional and national estimates for 2019. Having more children was a risk factor for stunting, whereas married mothers were associated with a lower risk. Risk factors for anemia included younger age and the male sex, whereas those for STH, older age, incomplete vaccination, and a lower socioeconomic status. Mothers’ employment outside the home was also associated with a lower STH risk. This recent evidence highlights the need for prompt and integrated clinical attention and public health actions to address both short- and long-term health consequences in this vulnerable child age group. The integration of a monitoring and evaluation framework is important to effectively manage these conditions, optimize resources and accountability, and show their impact.

Daily Rice Bran Consumption for 6 Months Influences Serum Glucagon-Like Peptide 2 and Metabolite Profiles without Differences in Trace Elements and Heavy Metals in Weaning Nicaraguan Infants at 12 Months of Age

BACKGROUND

Environmental enteric dysfunction (EED) is associated with chronic gut inflammation affecting nutrient absorption and development of children, primarily in low- and middle-income countries. Several studies have shown that rice bran (RB) supplementation provides nutrients and modulates gut inflammation, which may reduce risk for undernutrition.

OBJECTIVE

The aim was to evaluate the effect of daily RB dietary supplementation for 6 mo on serum biomarkers in weaning infants and associated changes in serum and stool metabolites.

METHODS

A 6-mo randomized-controlled dietary intervention was conducted in a cohort of weaning 6-mo-old infants in León, Nicaragua. Anthropometric indices were obtained at 6, 8, and 12 mo. Serum and stool ionomics and metabolomics were completed at the end of the 6-mo intervention using inductively coupled plasma MS and ultra-high performance LC-tandem MS. The ɑ1-acid glycoprotein, C-reactive protein, and glucagon-like peptide 2 (GLP-2) serum EED biomarkers were measured by ELISA.

RESULTS

Twenty-four infants in the control group and 23 in the RB group successfully completed the 6-mo dietary intervention with 90% dietary compliance. RB participants had higher concentrations of GLP-2 as compared with control participants at 12 mo [median (IQR): 743.53 (380.54) pg/mL vs. 592.50 (223.59) pg/mL; P = 0.04]. Metabolite profiles showed significant fold differences of 39 serum metabolites and 44 stool metabolites from infants consuming RB compared with control, and with significant metabolic pathway enrichment scores of 4.7 for the tryptophan metabolic pathway, 5.7 for polyamine metabolism, and 5.7 for the fatty acid/acylcholine metabolic pathway in the RB group. No differences were detected in serum and stool trace elements or heavy metals following daily RB intake for 6 mo.

CONCLUSIONS

RB consumption influences a suite of metabolites associated with growth promotion and development, while also supporting nutrient absorption as measured by changes in serum GLP-2 in Nicaraguan infants. This clinical trial was registered at https://clinicaltrials.gov as NCT02615886.

Factors associated with undernutrition among children aged between 6-36 months in Semien Bench district, Ethiopia

BACKGROUND

Malnutrition is a term used to refer a condition of both excessive and under-nutrition. Even in the 21st c, it is yet among the major public health challenges that affect the health, growth, and development of millions of children across continents. Studies show that malnutrition during early childhood could result in devastating long-term effects such as poor school performance, weak immune system, and growth and development. Unfortunately, Ethiopia is among the developing countries hard hit by the problem of malnutrition (under-nutrition).

OBJECTIVE

To assess the magnitude of stunting, wasting, and underweight and risk factors associated with them; among Children aged between 6- 36 months.

METHODS

A community-based cross-sectional study design was conducted on 700 study participants from April to May 2020. Nutritional status of children aged between 6-36 months was determined based on the WHO reference population with Z score ≤ -2 SD (HAZ, WHZ and WAZ) was looked upon for stunting, wasting and underweight accordingly. Data were collected through structured and measuring anthropometric of the eligible sample unit. The questionnaire data were first entered into Epi-data and later analyzed following binary and multiple logistic regression analysis procedures with the help of IBM SPSS 26. Adjusted odds ratios, with 95% CI of the association and statistical significance declared at P-values ≤ 0.05 in this study.

RESULTS

In the present study, the response rate of the respondent was 100%. Factors significantly associated with undernutrition: stunting, Mothers who have no formal education (AOR = 2.58, 95% CI; 1.44-4.63), food insecure (AOR = 1.9, 95% CI; 1.23-2.9) and children had no feeding plate (AOR = 1.53, 95% CI; 1.07-2.19).

FOR UNDERWEIGHT

have not individual feeding plate (AOR = 2.39, 95% CI; 1.42-4.03), poor dietary diversity (AOR = 1.82, 95% CI; 1.23-2.69) and food insecurity (AOR = 4.24, 95% CI; 2.68-6.71).We have also identified age between 6-11 months (AOR = 6.81, 95% CI; 2.93-15.79), 12-23 months (AOR = 2.28, 95% CI; 1.03-5.06), food insecure (AOR = 10.34, 95% CI; 5.22-20.45) and poor dietary diversity (AOR = 5.58, 95% CI; 2.36-13.19) as risk factors associated with wasting.

CONCLUSION

This study relived that six variables significantly associate with undernutrition. These are: children have not his/her own feeding plate, household food insecurity, mother who had no formal education, poor dietary diversity and children aged between 6-11months and children age 6-23 months. Based on the findings of this study, the following recommendations are made. First, strategies and programs targeted towards the reduction and prevention of undernutrition among 6-36-month children should be made at all level to improve childhood nutritional status. Second, provide health information to families regarding the importance of separating children's feeding plate. Three, provide nutritional counselling about feeding practice and dietary diversity for mothers who have no formal education.

Maternal postpartum deworming and infant milk intake: Secondary outcomes from a trial

The World Health Organization recommends deworming to reduce soil-transmitted helminth (STH)-attributable morbidity in women of reproductive age, including pregnant and lactating women, to reduce blood loss, iron deficiency anaemia and nutrient malabsorption. This study assessed the impact of maternal postpartum deworming with albendazole approximately 1 day after delivery on infant milk intake among a subset of 216 randomly selected mother-infant pairs recruited into a large trial in Peru. Infant milk intake was measured using the deuterium-oxide method at 1- and 6-month postpartum. Maternal STH infection was measured at 6-month postpartum. At 1-month postpartum, mean intake was 756 ± 16 and 774 ± 18 mL day^-1 in the albendazole and placebo groups, respectively (mean difference: -18 mL day^-1 ; 95% CI: -65, 30). At 6-month postpartum, mean intake was 903 ± 16 and 908 ± 18 mL day^-1 in the albendazole and placebo groups, respectively (mean difference: -5 mL day^-1 ; 95% CI: -52, 43). There was no statistically significant difference in milk intake between groups at either time point. At 6-month postpartum, mothers infected with Trichuris trichiura had infants with higher milk intakes (adjusted mean difference: 70 mL day^-1 ; 95% CI: 20, 120) compared with uninfected mothers. However, there was no statistically significant difference in infant milk intake between mothers who had moderate-and-heavy intensity infection compared with the comparison group (mothers with no and light intensity infection). A lower prevalence and intensity of infection, and inclusion of uninfected mothers in both arms of the trial, resulting in effect dilution, may explain the null findings.

Drivers of stunting reduction in Peru: a country case study

BACKGROUND

Peru reduced its under-5 child stunting prevalence notably from 31.3% in 2000 to 13.1% in 2016.

OBJECTIVES

We aimed to study factors and key enablers of child stunting reduction in Peru from 2000-2016.

METHODS

Demographic and Health Surveys were used to conduct descriptive analyses [height-for-age z scores (HAZ) means and distributions, equity analysis, predicted child growth curves through polynomial regressions] and advanced regression analyses. An ecological (at department level) multilevel regression analysis was conducted to identify the major predictors of stunting decline from 2000 to 2016, and Oaxaca-Blinder decomposition was conducted to identify the relative contribution of each factor to child HAZ change. A systematic literature review, policy and program analysis, and interviews with relevant stakeholders were conducted to understand key drivers of stunting decline in Peru.

RESULTS

The distribution of HAZ scores showed a slight rightward shift from 2000 to 2007/2008, and a greater shift from 2007/2008 to 2016. Stunting reduction was higher in the lowest wealth quintile, in rural areas, and among children with the least educated mothers. Decomposing predicted changes showed that the most important factors were increased maternal BMI and maternal height, improved maternal and newborn health care, increased parental education, migration to urban areas, and reduced fertility. Key drivers included the advocacy role of civil society and political leadership around poverty and stunting reduction since the early 2000s. Key enablers included the economic growth and the consolidation of democracy since the early 2000s, and the acknowledgement that stunting reduction needs much more than food supplementation.

CONCLUSIONS

Peru reduced child stunting owing to improved socioeconomic determinants, sustained implementation of out-of-health-sector and within-health-sector changes, and implementation of health interventions. These efforts were driven through a multisectoral approach, strong civil society advocacy, and keen political leadership. Peru's experience offers useful lessons on how to tackle the problem of stunting under differing scenarios, with the participation of multiple sectors.

Evaluation of Peruvian Government Interventions to Reduce Childhood Anemia

Background:

In Peru, anemia has been a persistent health problem that is known to lead to irreversible cognitive and developmental deficits in children. The Peruvian government has recently made anemia a primary health concern by passing legislation in 2017 that makes anemia an intersectoral priority. This new legislation fortifies previous programs while creating new programs that target specific age groups.

Objectives:

Evaluate the effectiveness of government programs in Madre de Dios, Peru to reduce anemia prevalence and increase hemoglobin levels among children ages 2–11 years old.

Methods:

Propensity scores are used to match 688 children enrolled in 2018, after the legislation, and 2,140 children enrolled in previous studies our team conducted in the region between 2014 and 2017, based on sex, age (years), intervention status (prior/post), community income, presence of a health post in the community (yes/no), community type (indigenous, non-indigenous rural, non-indigenous urban) and road access (fraction of the number of months out of the year with road access). A pseudo matched case-control analysis to evaluate changes in anemia prevalence and hemoglobin was conducted using t-tests and multivariate models. Program effectiveness is evaluated overall, by age groups (2–4, 5–7 and 8–11 years old), and community type (indigenous vs. urban).

Findings:

The adjusted odds ratio indicated lower odds of anemia (OR = 0.31, 95%CI 0.17–0.54) for children exposed to the anemia prevention programs vs. those not exposed. The effect was not significantly different across age groups; however, the intervention effects significantly differed by community type among children 8–11 years old, with urban children less likely to benefit from anemia interventions (OR = 0.69, 95% CI 0.38–1.25) compared to indigenous children (OR = 0.21, 95% CI 0.08–0.56).

Conclusion:

Government programs to reduce anemia in Madre de Dios were found to be associated with reduced anemia prevalence in the study communities. However, the lack of program monitoring precludes the attribution of anemia decline to specific interventions or program components. In addition, regional anemia prevalence remains high according to the 2019 Demographic and Health Survey, suggesting impaired population impact. Program monitoring and evaluation is a key component of health interventions to improve program implementation effectiveness.

Assessing school-lunch feeding and nutrition education strategy for healthier kids in selected Philippine public schools

BACKGROUND

Nutrition interventions during the early years of a child's life are anchored on the need to provide good nutrition and proper health care to optimize their growth potential as adults. In the Philippines, undernutrition is a persistent problem among 0-10 year old Filipino children. In this age group, children consume a diet poor in quantity and quality.

AIM

This study aimed to assess the effects of a school-lunch and nutrition education intervention among schoolchildren in terms of attaining good nutrition.

METHOD

Using a quasi-experimental design, children aged 7-9 years from public elementary schools in the province of Laguna, Philippines were categorized into three intervention groups and one non-intervention group. Anthropometric measurements; nutrition knowledge, attitude and behavior; and food intake among children and households were collected at baseline and endline periods. SPSS for Windows version 16 and Stata version 15 were utilized for data analysis.

RESULTS

Mean scores on knowledge, attitude and behavior of schoolchildren in intervention groups increased significantly at endline (p<0.05). Protein requirement was met by more children and households than the energy requirement. Most children with normal nutritional status after the interventions (25.3%) belonged to the group with the complete intervention of school-lunch and nutrition education.

CONCLUSIONS

The provision of both school-lunch feeding and nutrition education is effective in improving the knowledge, attitude and behavior scores and nutritional status of schoolchildren. The adoption and institutionalization of complete intervention with school-lunch and nutrition education in elementary public schools should be pursued.

Rice bran supplementation modulates growth, microbiota and metabolome in weaning infants: a clinical trial in Nicaragua and Mali

Rice bran supplementation provides nutrients, prebiotics and phytochemicals that enhance gut immunity, reduce enteric pathogens and diarrhea, and warrants attention for improvement of environmental enteric dysfunction (EED) in children. EED is a subclinical condition associated with stunting due to impaired nutrient absorption. This study investigated the effects of rice bran supplementation on weight for age and length for age z-scores (WAZ, LAZ), EED stool biomarkers, as well as microbiota and metabolome signatures in weaning infants from 6 to 12 months old that reside in Nicaragua and Mali. Healthy infants were randomized to a control (no intervention) or a rice bran group that received daily supplementation with increasing doses at each month (1–5 g/day). Stool microbiota were characterized using 16S rDNA amplicon sequencing. Stool metabolomes were analyzed using ultra-high-performance liquid-chromatography tandem mass-spectrometry. Statistical comparisons were completed at 6, 8, and 12 months of age. Daily consumption of rice bran was safe and feasible to support changes in LAZ from 6–8 and 8–12 months of age in Nicaragua and Mali infants when compared to control. WAZ was significantly improved only for Mali infants at 8 and 12 months. Mali and Nicaraguan infants showed major differences in the overall gut microbiota and metabolome composition and structure at baseline, and thus each country cohort demonstrated distinct microbial and metabolite profile responses to rice bran supplementation when compared to control. Rice bran is a practical dietary intervention strategy that merits development in rice-growing regions that have a high prevalence of growth stunting due to malnutrition and diarrheal diseases. Rice is grown as a staple food, and the bran is used as animal feed or wasted in many low- and middle-income countries where EED and stunting is prevalent.

Implementing neuroimaging and eye tracking methods to assess neurocognitive development of young infants in low- and middle-income countries

Infants and children in low- and middle-income countries (LMICs) are frequently exposed to a range of environmental risk factors which may negatively affect their neurocognitive development. The mechanisms by which factors such as undernutrition and poverty impact development and cognitive outcomes in early childhood are poorly understood. This lack of knowledge is due in part to a paucity of objective assessment tools which can be implemented across different cultural settings and in very young infants. Over the last decade, technological advances, particularly in neuroimaging, have opened new avenues for research into the developing human brain, allowing us to investigate novel biological associations. This paper presents functional near-infrared spectroscopy (fNIRS), electroencephalography (EEG) and eye tracking (ET) as objective, cross-cultural methods for studying infant neurocognitive development in LMICs, and specifically their implementation in rural Gambia, West Africa. These measures are currently included, as part of a broader battery of assessments, in the Brain Imaging for Global Health (BRIGHT) project, which is developing brain function for age curves in Gambian and UK infants from birth to 24 months of age. The BRIGHT project combines fNIRS, EEG and ET with behavioural, growth, health and sociodemographic measures. The implementation of these measures in rural Gambia are discussed, including methodological and technical challenges that needed to be addressed to ensure successful data acquisition. The aim is to provide guidance to other groups seeking to implement similar methods in their research in other LMICs to better understand associations between environmental risk and early neurocognitive development.

Implementing neuroimaging and eye tracking methods to assess neurocognitive development of young infants in low- and middle-income countries

Infants and children in low- and middle-income countries (LMICs) are frequently exposed to a range of environmental risk factors which may negatively affect their neurocognitive development. The mechanisms by which factors such as undernutrition and poverty impact development and cognitive outcomes in early childhood are poorly understood. This lack of knowledge is due in part to a paucity of objective assessment tools which can be implemented across different cultural settings and in very young infants. Over the last decade, technological advances, particularly in neuroimaging, have opened new avenues for research into the developing human brain, allowing us to investigate novel biological associations. This paper presents functional near-infrared spectroscopy (fNIRS), electroencephalography (EEG) and eye tracking (ET) as objective, cross-cultural methods for studying infant neurocognitive development in LMICs, and specifically their implementation in rural Gambia, West Africa. These measures are currently included, as part of a broader battery of assessments, in the Brain Imaging for Global Health (BRIGHT) project, which is developing brain function for age curves in Gambian and UK infants from birth to 24 months of age. The BRIGHT project combines fNIRS, EEG and ET with behavioural, growth, health and sociodemographic measures. The implementation of these measures in rural Gambia are discussed, including methodological and technical challenges that needed to be addressed to ensure successful data acquisition. The aim is to provide guidance to other groups seeking to implement similar methods in their research in other LMICs to better understand associations between environmental risk and early neurocognitive development.

Environmental Risk Factors Associated with Child Stunting: A Systematic Review of the Literature

BACKGROUND

Stunting, a form of malnutrition characterized by impaired linear growth in the first two years of life, affects one quarter of children globally. While nutritional status remains the key cause of stunting, there is evidence that environmental risk factors are associated with stunting.

OBJECTIVE

The objective of this review is to explore the current literature and compile the environmental risk factors that have been associated with stunting. Further, we seek to discover which risk factors act independently of nutritional intake.

METHODS

A systematic search of the literature was performed using PubMed, EMBASE, Scopus, TOXNET, and CINAHL. A search of the grey literature was conducted. Papers were included in this review if they examined an association between childhood stunting and exposure to environmental risk factors.

FINDINGS

We included 71 reports in the final analysis. The included studies showed that foodborne mycotoxins, a lack of adequate sanitation, dirt floors in the home, poor quality cooking fuels, and inadequate local waste disposal are associated with an increased risk of childhood stunting. Access to safe water sources was studied in a large number of studies, but the results remain inconclusive due to inconsistent study findings. Limited studies were available for arsenic, mercury, and environmental tobacco, and thus their role in stunting remains inconclusive. The identified research did not control for nutritional intake. A causal model identified solid fuel use and foodborne mycotoxins as being environmental risk factors with the potential to have direct effects on childhood growth.

CONCLUSIONS

A diverse range of environmental risk factors are, to varying degrees, associated with stunting, demonstrating the importance of considering how the environment interacts with nutrition. Health promotion activities may be more effective if they consider environmental factors alongside nutritional interventions.

Environmental Risk Factors Associated with Child Stunting: A Systematic Review of the Literature

BACKGROUND

Stunting, a form of malnutrition characterized by impaired linear growth in the first two years of life, affects one quarter of children globally. While nutritional status remains the key cause of stunting, there is evidence that environmental risk factors are associated with stunting.

OBJECTIVE

The objective of this review is to explore the current literature and compile the environmental risk factors that have been associated with stunting. Further, we seek to discover which risk factors act independently of nutritional intake.

METHODS

A systematic search of the literature was performed using PubMed, EMBASE, Scopus, TOXNET, and CINAHL. A search of the grey literature was conducted. Papers were included in this review if they examined an association between childhood stunting and exposure to environmental risk factors.

FINDINGS

We included 71 reports in the final analysis. The included studies showed that foodborne mycotoxins, a lack of adequate sanitation, dirt floors in the home, poor quality cooking fuels, and inadequate local waste disposal are associated with an increased risk of childhood stunting. Access to safe water sources was studied in a large number of studies, but the results remain inconclusive due to inconsistent study findings. Limited studies were available for arsenic, mercury, and environmental tobacco, and thus their role in stunting remains inconclusive. The identified research did not control for nutritional intake. A causal model identified solid fuel use and foodborne mycotoxins as being environmental risk factors with the potential to have direct effects on childhood growth.

CONCLUSIONS

A diverse range of environmental risk factors are, to varying degrees, associated with stunting, demonstrating the importance of considering how the environment interacts with nutrition. Health promotion activities may be more effective if they consider environmental factors alongside nutritional interventions.

Influence of Maternal Fish Intake on the Anthropometric Indices of Children in the Western Amazon

We studied trends in fish intake among pregnant women living in the Madeira River Basin in Rondônia State, Brazil, to investigate the influence of maternal fish intake on anthropometric indices of children followed up to 5 years. Maternal fish intake was assessed using hair mercury concentrations of mothers and children at delivery and 6, 24, and 59 months. Data analysis was performed using a linear mixed-effect model. Mothers were predominantly young, had low incomes and limited schooling, and breastfed for >6 months. Only 1.9% of children had low birth weight. Anthropometric indices in approximately 80% of the study population showed Z-score values ranging from ≥-2 to ≤1. The influence of maternal fish intake on anthropometric indices, including height-to-age (H/A), weight-to-age (W/A), and weight-to-height (W/H) were not statistically significant after model adjustments. However, higher income and larger birth weight had a positive influence on H/A and W/A, whereas W/H gain was favored by higher maternal educational status and breastfeeding duration. Other variables (hemoglobin concentration and maternal age) had a positive significant influence on anthropometric indices. Maternal fish intake (or its attendant MeHg exposure) did not affect children growth. Nevertheless, it is advisable to avoid mercury-contaminated fish during pregnancy and childhood.

A Double-Blind Randomized Controlled Trial of Maternal Postpartum Deworming to Improve Infant Weight Gain in the Peruvian Amazon

Background

Nutritional interventions targeting the critical growth and development period before two years of age can have the greatest impact on health trajectories over the life course. Compelling evidence has demonstrated that interventions investing in maternal health in the first 1000 days of life are beneficial for both mothers and their children. One such potential intervention is deworming integrated into maternal postpartum care in areas where soil-transmitted helminth (STH) infections are endemic.

Methodology/Principal Findings

From February to August 2014, 1010 mother-infant pairs were recruited into a trial aimed at assessing the effectiveness of maternal postpartum deworming on infant and maternal health outcomes. Following delivery, mothers were randomly assigned to receive either single-dose 400 mg albendazole or placebo. Participants were followed-up at 1 and 6 months postpartum. There was no statistically significant difference in mean weight gain between infants in the experimental and control groups (mean difference: -0.02; 95% CI: -0.1, 0.08) at 6 months of age. Further, deworming had no effect on measured infant morbidity indicators. However, ad hoc analyses restricted to mothers who tested positive for STHs at baseline suggest that infants of mothers in the experimental group had greater mean length gain in cm (mean difference: 0.8; 95% CI: 0.1, 1.4) and length-for-age z-score (mean difference: 0.5; 95% CI: 0.2, 0.8) at 6 months of age.

Conclusions/Significance

In a study population composed of both STH-infected and uninfected mothers, maternal postpartum deworming was insufficient to impact infant growth and morbidity indicators up to 6 months postpartum. Among STH-infected mothers, however, important improvements in infant length gain and length-for-age were observed. The benefits of maternal postpartum deworming should be further investigated in study populations having higher overall prevalences and intensities of STH infections and, in particular, where whipworm and hookworm infections are of public health concern.

Trial registration

ClinicalTrials.gov (NCT01748929).

Worldwide, over one billion people are infected with intestinal worms (roundworms, whipworms, and hookworms). In worm-endemic areas, women of reproductive age are a high risk group for infection because of their poor nutritional status and increased physiological needs during pre-pregnancy, pregnancy, and lactation. To measure the effect of providing mothers with deworming treatment soon after delivery, we conducted a trial in 1010 mother-infant pairs. Mothers were randomly assigned to receive either a single-dose deworming tablet or a placebo tablet. Mothers and their infants were visited in their homes at 1 and 6 months following delivery. At the 6-month time point, among all mother-infant pairs, we could not detect an effect of deworming on infant growth or morbidity. We did, however, observe that, among women who were infected with intestinal worms at baseline, deworming had a beneficial effect on important infant growth outcomes. The potential benefit of maternal postpartum deworming in populations with higher prevalences and intensities of intestinal worms, particularly where infections with whipworm and hookworm predominate, warrants further investigation.

Adverse Events from a Randomized, Multi-Arm, Placebo-Controlled Trial of Mebendazole in Children 12-24 Months of Age

Large-scale deworming interventions, using anthelminthic drugs, are recommended in areas where the prevalence of soil-transmitted helminth infection is high. Anthelminthic safety has been established primarily in school-age children. Our objective was to provide evidence on adverse events from anthelminthic use in early childhood. A randomized multi-arm, placebo-controlled trial of mebendazole, administered at different times and frequencies, was conducted in children 12 months of age living in Iquitos, Peru. Children were followed up to 24 months of age. The association between mebendazole administration and the occurrence of a serious or minor adverse event was determined using logistic regression. There was a total of 1,686 administrations of mebendazole and 1,676 administrations of placebo to 1,760 children. Eighteen serious adverse events (i.e., 11 deaths and seven hospitalizations) and 31 minor adverse events were reported. There was no association between mebendazole and the occurrence of a serious adverse event (odds ratio [OR] = 1.21; 95% confidence interval [CI] = 0.47, 3.09) or a minor adverse event (OR = 0.84; 95% CI = 0.41, 1.72). Results from our trial support evidence of safety in administering mebendazole during early childhood. These results support World Health Organization deworming policy and the scaling up of interventions to reach children as of 12 months of age in endemic areas.

Complexities and Perplexities: A Critical Appraisal of the Evidence for Soil-Transmitted Helminth Infection-Related Morbidity

BACKGROUND

Soil-transmitted helminths (STH) have acute and chronic manifestations, and can result in lifetime morbidity. Disease burden is difficult to quantify, yet quantitative evidence is required to justify large-scale deworming programmes. A recent Cochrane systematic review, which influences Global Burden of Disease (GBD) estimates for STH, has again called into question the evidence for deworming benefit on morbidity due to STH. In this narrative review, we investigate in detail what the shortfalls in evidence are.

METHODOLOGY/PRINCIPAL FINDINGS

We systematically reviewed recent literature that used direct measures to investigate morbidity from STH and we critically appraised systematic reviews, particularly the most recent Cochrane systematic review investigating deworming impact on morbidity. We included six systematic reviews and meta-analyses, 36 literature reviews, 44 experimental or observational studies, and five case series. We highlight where evidence is insufficient and where research needs to be directed to strengthen morbidity evidence, ideally to prove benefits of deworming.

CONCLUSIONS/SIGNIFICANCE

Overall, the Cochrane systematic review and recent studies indicate major shortfalls in evidence for direct morbidity. However, it is questionable whether the systematic review methodology should be applied to STH due to heterogeneity of the prevalence of different species in each setting. Urgent investment in studies powered to detect direct morbidity effects due to STH is required.

The effect of deworming on early childhood development in Peru: A randomized controlled trial

Background

There is a knowledge gap on the effect of early childhood deworming on development in low- and middle-income countries. This evidence is important in the critical window of growth and development before two years of age.

Methods

A randomized controlled trial of the benefit, and optimal timing and frequency, of deworming on development was conducted in Iquitos, Peru. Children were enrolled during routine 12-month growth and development visits and randomly allocated to: (1) deworming at the 12-month visit and placebo at the 18-month visit; (2) placebo at the 12-month visit and deworming at the 18-month visit; (3) deworming at the 12 and 18-month visits; or (4) placebo at the 12 and 18-month visits. The Bayley Scales of Infant Development III was used to assess cognitive, language and motor skills at the 12 and 24-month visits. One-way ANOVA analyses used an intention-to-treat approach.

Results

Between September 2011 and June 2012, 1760 children were enrolled. Attendance at the 24-month visit was 88.8% (n=1563). Raw scores on all subtests increased over 12 months; however, cognitive and expressive language scaled scores decreased. There was no statistically significant benefit of deworming, or effect of timing or frequency, on any of the development scores. Baseline height and weight and maternal education were associated with development scores at 24 months.

Conclusions

After 12 months of follow-up, an overall benefit of deworming on cognition, language or fine motor development was not detected. Additional integrated child and maternal interventions should be considered to prevent developmental deficits in this critical period.

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This is the first and largest deworming trial exclusively in 1-year-old children.

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We examined the effect of deworming on early childhood development.

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Deworming did not impact cognition, language or motor skills.

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Concomitant poverty and malnutrition may obscure the true effect of deworming.

The Effect of Deworming on Growth in One-Year-Old Children Living in a Soil-Transmitted Helminth-Endemic Area of Peru: A Randomized Controlled Trial

Background

Appropriate health and nutrition interventions to prevent long-term adverse effects in children are necessary before two years of age. One such intervention may include population-based deworming, recommended as of 12 months of age by the World Health Organization in soil-transmitted helminth (STH)-endemic areas; however, the benefit of deworming has been understudied in early preschool-age children.

Methodology/Principal Findings

A randomized, double-blind, placebo-controlled trial was conducted to determine the effect of deworming (500 mg single-dose crushed mebendazole tablet) on growth in one-year-old children in Iquitos, Peru. Children were enrolled during their routine 12-month growth and development clinic visit and followed up at their 18 and 24-month visits. Children were randomly allocated to: Group 1: deworming at 12 months and placebo at 18 months; Group 2: placebo at 12 months and deworming at 18 months; Group 3: deworming at both 12 and 18 months; or Group 4: placebo at both 12 and 18 months (i.e. control group). The primary outcome was weight gain at the 24-month visit. An intention-to-treat approach was used. A total of 1760 children were enrolled between September 2011 and June 2012. Follow-up of 1563 children (88.8%) was completed by July 2013. STH infection was of low prevalence and predominantly light intensity in the study population. All groups gained between 1.93 and 2.05 kg on average over 12 months; the average difference in weight gain (kg) compared to placebo was: 0.05 (95% CI: -0.05, 0.17) in Group 1; -0.07 (95%CI: -0.17, 0.04) in Group 2; and 0.04 (95%CI: -0.06, 0.14) in Group 3. There was no statistically significant difference in weight gain in any of the deworming intervention groups compared to the control group.

Conclusions

Overall, with one year of follow-up, no effect of deworming on growth could be detected in this population of preschool-age children. Low baseline STH prevalence and intensity and/or access to deworming drugs outside of the trial may have diluted the potential effect of the intervention. Additional research is required to overcome these challenges and to contribute to strengthening the evidence base on deworming.

Trial Registration

ClinicalTrials.gov (NCT01314937)

The World Health Organization recommends starting population-based deworming interventions as of 12 months of age where intestinal worm infection is common; however, little is known about the benefits in early preschool-age children. We conducted a clinical trial to determine the effect of deworming on growth in one-year-old children in Peru. Participating children were randomly assigned to: 1) deworming at 12 months of age; 2) deworming at 18 months of age; 3) deworming at 12 and 18 months of age; or 4) no deworming (i.e. control group). A total of 1760 children were enrolled between September 2011 and June 2012, and followed up for one year. Overall, with one year of follow-up, no effect of deworming on growth could be detected in this population of preschool-age children. The potential benefit of the intervention may have been affected by low baseline infection prevalence and/or low compliance to the randomly assigned intervention. Additional research is required to overcome these challenges and to contribute to strengthening the evidence base on deworming.

Novel approaches to the diagnosis of Strongyloides stercoralis infection

Strongyloides stercoralis differs from the other soil-transmitted helminths because it puts infected subjects at risk of a fatal syndrome (in cases of immunosuppression for medical conditions, immunosuppressant therapies, or both). Chronic strongyloidiasis is often a non-severe condition, or is sometimes even asymptomatic, but diagnosis and effective therapy are essential in order to eradicate the infection and the life-long risk involved. Therefore, diagnostic methods need to be highly sensitive. Stool microscopy and the Kato-Katz technique are commonly used in prevalence studies, but they are inadequate for S. stercoralis detection. This is probably the main reason why the global prevalence has long been underestimated. Concentration methods, the Baermann technique and Koga agar plate culture have better, but still unsatisfactory, sensitivity. Serological tests have demonstrated higher sensitivity; although some authors have concerns about their specificity, it is possible to define cut-off values over which infection is almost certain. In particular, the luciferase immunoprecipitation system technique combined with a recombinant antigen (NIE) demonstrated a specificity of almost 100%. ELISA coproantigen detection has also shown promising results, but still needs full evaluation. Molecular diagnostic methods are currently available in a few referral centres as in-house techniques. In this review, on the basis of the performance of the different diagnostic methods, we outline diagnostic strategies that could be proposed for different purposes, such as: prevalence studies in endemic areas; individual diagnosis and screening; and monitoring of cure in clinical care and clinical trials.