Complementary and alternative metrics for tracking population-level trends in child linear growth.

Stunting prevalence is commonly used to track population-level child nutritional status. However, other metrics derived from anthropometric datasets may be used as alternatives to stunting or provide complementary perspectives on the status of linear growth faltering in low- and middle-income countries (LMICs). Data from 156 Demographic and Health Surveys in 63 LMICs (years 2000 to 2020) were used to generate 2 types of linear growth metrics: (i) measures of location of height distributions (including stunting) for under-5 years (<5y) and 2 to 5 years (2-5y); (ii) model-derived metrics including predicted mean height-for-age z-score (HAZ) at 0, 2, and 5 years; interval slopes of HAZ, height-for-age difference (HAD), and growth delay (GD) from 1 month to 2 years (1mo-2y) and 2-5y; and the SITAR intensity parameter (SITAR-IP) for <5y. Using Spearman's rank correlation coefficient (r), metrics were considered alternatives to stunting if very strongly correlated with stunting (|r|≥0.95) and at least as strongly correlated as stunting with selected population indicators (under 5y mortality, gross domestic product, maternal education). Metrics were considered complementary if less strongly correlated with stunting (|r|<0.95) yet correlated with population indicators. We identified 6 of 15 candidate metrics (stunting 2-5y, mean HAZ <5y and 2-5y, p25 HAZ <5y and 2-5y, predicted HAZ at 2y) as potential alternatives to stunting and 6 as complementary metrics (SITAR-IP, predicted HAZ at 5y, HAZ slope 1m-2y, HAD slope 1m-2y, GD slopes 1m-2y and 2-5y). Three metrics (HAZ slope 2-5y, HAD slope 2-5y years and predicted HAZ at birth) had weak correlations with population indicators (|r| ≤ 0.43). In conclusion, several linear growth metrics could serve as alternatives to stunting prevalence and others may be complementary to stunting in tracking global progress in child health and nutrition. Further research is needed to explore the real-world utility of these alternative and complementary metrics.

Perspective: Understanding the Intersection of Climate/Environmental Change, Health, Agriculture, and Improved Nutrition - A Case Study: Type 2 Diabetes.

Efforts to promote health through improved diet and nutrition demand an appreciation of the nutritional ecology that accounts for the intersection of agriculture, food systems, health, disease and a changing environment. The complexity and implications of this ecology is exemplified by current trends and efforts to address nutrition-related non-communicable diseases (NCDs), most prominently type 2 diabetes. The global prevalence of type 2 diabetes continues to rise unabated. Of particular concern is how to address the unhealthy dietary patterns that are contributing to this pandemic in a changing environment. A multi- disciplinary approach is required that will engage those communities that comprise the continuum of effort from research to translation and implementation of evidence-informed interventions, programs and policies. Using the prevention of type 2 diabetes by increasing fruit and vegetable consumption as an exemplar, we argue that the ability to effect positive change in this and other persistent nutrition-related problems can be achieved by moving away from siloed approaches that limit the integration of key components of the diet-health continuum. Ultimately the impact of preventing type 2 diabetes via increased fruit and vegetable consumption will depend on how the entire diet changes, not just fruits and vegetables. In addition, the rapidly changing physical environment that will confront our food production system going forward will also shape the interventions that are possible. Nonetheless, the proposed "team science" approach that accounts for all the elements of the nutrition ecology will better position us to achieve public health goals through safe and sustainable food systems.

Impact of iron fortification on the geospatial patterns of malaria and non-malaria infection risk among young children: a secondary spatial analysis of clinical trial data from Ghana.

OBJECTIVES: Patterns of infection among children with varying levels of iron status in a malaria endemic area may vary spatially in ways requiring integrated infection and iron deficiency control programmes. The objective of this secondary analysis was to determine the geospatial factors associated with malaria and non-malaria infection status among young Ghanaian children at the end of a 5-month iron intervention trial. DESIGN: Cluster-randomised controlled trial. SETTING: Rural Ghana PARTICIPANTS: 1943 children (6-35 months of age) with geocoded compounds. INTERVENTIONS: Point-of-use fortification with micronutrient powders containing vitamins and minerals with or without iron. PRIMARY AND SECONDARY OUTCOME MEASURES: Generalised linear geostatistical models with a Matern spatial correlation function were used to analyse four infection response variables, defined using different combinations of inflammation (C-reactive protein, CRP >5 mg/L) and malaria parasitaemia. Analyses were also stratified by treatment group to assess the independent effects of the iron intervention. RESULTS: The by-group and combined-group analyses both showed that baseline infection status was the most consistent predictor of endline infection risk, particularly when infection was defined using parasitaemia. In the No-iron group, age above 24 months and weight-for-length z-score at baseline were associated with high CRP at endline. Higher asset score was associated with a 12% decreased odds of endline infection, defined as CRP >5 mg/L and/or parasitaemia (OR 0.88, 95% credible interval 0.78 to 0.98), regardless of group. Maps of the predicted risk and spatial random effects showed a defined low-risk area around the District centre, regardless of how infection was defined. CONCLUSION: In a clinical trial setting of iron fortification, where all children receive treated bed nets and access to malaria treatment, there may be geographical variation in the risk of infection with distinct high-risk and low-risk areas, particularly around municipal centres. TRIAL REGISTRATION NUMBER: clinicaltrials.gov, NCT01001871.

The intersection of climate/environment, food, nutrition and health: crisis and opportunity.

Climate/environmental change (C-E-C) is affecting human health and quality of life. Significant attention has been given to the impact of C-E-C on food supply, and food as a vehicle for exposure. However, C-E-C has been superimposed on prevalent malnutrition, infectious and non-communicable diseases. We discuss why nutrition is not synonymous with food and must be viewed as a biological variable that affects and is affected by both C-E-C as well as the current global health challenges. The nexus of C-E-C, food, nutrition and health must be considered in the development of safe and efficacious interventions. A case is presented for how the convergence of C-E-C, food/nutrition and health, presents an opportunity for more integrated approaches to achieve global health goals.

Geo-spatial factors associated with infection risk among young children in rural Ghana: a secondary spatial analysis.

BACKGROUND: Determining the spatial patterns of infection among young children living in a malaria-endemic area may provide a means of locating high-risk populations who could benefit from additional resources for treatment and improved access to healthcare. The objective of this secondary analysis of baseline data from a cluster-randomized trial among 1943 young Ghanaian children (6-35 months of age) was to determine the geo-spatial factors associated with malaria and non-malaria infection status. METHODS: Spatial analyses were conducted using a generalized linear geostatistical model with a Matern spatial correlation function and four definitions of infection status using different combinations of inflammation (C-reactive protein, CRP > 5 mg/L) and malaria parasitaemia (with or without fever). Potentially informative variables were included in a final model through a series of modelling steps, including: individual-level variables (Model 1); household-level variables (Model 2); and, satellite-derived spatial variables (Model 3). A final (Model 4) and maximal model (Model 5) included a set of selected covariates from Models 1 to 3. RESULTS: The final models indicated that children with inflammation (CRP > 5 mg/L) and/or any evidence of malaria parasitaemia at baseline were more likely to be under 2 years of age, stunted, wasted, live further from a health facility, live at a lower elevation, have less educated mothers, and higher ferritin concentrations (corrected for inflammation) compared to children without inflammation or parasitaemia. Similar results were found when infection was defined as clinical malaria or parasitaemia with/without fever (definitions 3 and 4). Conversely, when infection was defined using CRP only, all covariates were non-significant with the exception of baseline ferritin concentration. In Model 5, all infection definitions that included parasitaemia demonstrated a significant interaction between normalized difference vegetation index and land cover type. Maps of the predicted infection probabilities and spatial random effect showed defined high- and low-risk areas that tended to coincide with elevation and cluster around villages. CONCLUSIONS: The risk of infection among young children in a malaria-endemic area may have a predictable spatial pattern which is associated with geographical characteristics, such as elevation and distance to a health facility. Original trial registration clinicaltrials.gov (NCT01001871).

Effect of iron fortification on malaria incidence in infants and young children in Ghana: a randomized trial.

IMPORTANCE: In sub-Saharan Africa, malaria is a leading cause of childhood morbidity and iron deficiency is among the most prevalent nutritional deficiencies. In 2006, the World Health Organization and the United Nations Children's Fund released a joint statement that recommended limiting use of iron supplements (tablets or liquids) among children in malaria-endemic areas because of concern about increased malaria risk. As a result, anemia control programs were either not initiated or stopped in these areas. OBJECTIVE: To determine the effect of providing a micronutrient powder (MNP) with or without iron on the incidence of malaria among children living in a high malaria-burden area. DESIGN, SETTING, AND PARTICIPANTS: Double-blind, cluster randomized trial of children aged 6 to 35 months (n = 1958 living in 1552 clusters) conducted over 6 months in 2010 in a rural community setting in central Ghana, West Africa. A cluster was defined as a compound including 1 or more households. Children were excluded if iron supplement use occurred within the past 6 months, they had severe anemia (hemoglobin level <7 g/dL), or severe wasting (weight-for-length z score <-3). INTERVENTIONS: Children were randomized by cluster to receive a MNP with iron (iron group; 12.5 mg/d of iron) or without iron (no iron group). The MNP with and without iron were added to semiliquid home-prepared foods daily for 5 months followed by 1-month of further monitoring. Insecticide-treated bed nets were provided at enrollment, as well as malaria treatment when indicated. MAIN OUTCOMES AND MEASURES: Malaria episodes in the iron group compared with the no iron group during the 5-month intervention period. RESULTS: In intention-to-treat analyses, malaria incidence overall was significantly lower in the iron group compared with the no iron group (76.1 and 86.1 episodes/100 child-years, respectively; risk ratio (RR), 0.87 [95% CI, 0.79-0.97]), and during the intervention period (79.4 and 90.7 episodes/100 child-years, respectively; RR, 0.87 [95% CI, 0.78-0.96]). In secondary analyses, these differences were no longer statistically significant after adjusting for baseline iron deficiency and anemia status overall (adjusted RR, 0.87; 95% CI, 0.75-1.01) and during the intervention period (adjusted RR, 0.86; 95% CI, 0.74-1.00). CONCLUSION AND RELEVANCE: In a malaria-endemic setting in which insecticide-treated bed nets were provided and appropriate malaria treatment was available, daily use of a MNP with iron did not result in an increased incidence of malaria among young children. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01001871.

Burden of anemia among indigenous populations.

An international perspective of the magnitude of anemia in indigenous peoples is currently lacking. The present systematic review was performed to characterize the global prevalence, severity, and etiology of anemia in indigenous peoples by conducting a systematic search of original research published in English from 1996 to February 2010 using PubMed, Medline, and Embase. A total of 50 studies, representing the following 13 countries, met the inclusion criteria: Australia, Brazil, Canada, Guatemala, India, Kenya, Malaysia, Mexico, New Zealand, Sri Lanka, Tanzania, the United States, and Venezuela. Results indicate major deficiencies in the coverage and quality of anemia monitoring data for indigenous populations worldwide. The burden of anemia is overwhelmingly higher among indigenous groups compared to the general population and represents a moderate (20-39.9%) to severe (≥40%) public health problem. For the most part, the etiology of anemia is preventable and includes inadequate diet, poor living conditions, and high infection rates (i.e., malaria and intestinal parasites). A concerted global effort is needed to reduce the worldwide burden of anemia in these marginalized populations.

A combination of pH-sensitive caplet coatings may be an effective noninvasive strategy to deliver bioactive substances, nutrients, or their precursors to the colon.

We hypothesize that bacterially synthesized nutrients in the large intestine may significantly influence the nutritional status of humans and, specifically, that of the colonocytes. In vivo research with human subjects in this area has been extremely limited because of the absence of a noninvasive means to quantitatively deliver test doses of nutrients, or their precursors, to the colon. The purpose of this study was to design and test the effectiveness of a pH-dependent coating in delivering intact placebo caplets to the large intestine. Barium sulphate caplet cores (19.1 mm x 9.7 mm) were coated with 2 different pH-dependent acrylic copolymer products, Eudragit L100 and S100, in either a 1:0 ratio (100% Eudragit L100) or 3:1 ratio (75% Eudragit L100 and 25% S100). The disintegration profile of each formulation was determined through in vitro testing, then caplets were sequentially administered to 10 healthy volunteers, and monitored in vivo via serial abdominal fluoroscopic images. Test caplets with the 3:1 coating formulation had a 40% higher colon-targeting specificity compared with the 1:0-coated caplets, and tended to begin disintegrating at a later time after administration (p = 0.09). The total time from administration to complete disintegration was also significantly longer for the 3:1-coated caplets (p = 0.003). These results suggest that barium sulphate caplets with a 3:1 acrylic copolymer coating formulation ratio (Eudragit L100 and S100) may be a suitable delivery system for quantifying the biosynthesis of nutrients in the human large intestine and measuring their absorption across the colonic epithelium.