Intestinal microbiota composition and efficacy of iron supplementation in Peruvian children.

OBJECTIVE: Despite repeated public health interventions, anemia prevalence among children remains a concern. We use an evolutionary medicine perspective to examine the intestinal microbiome as a pathway underlying the efficacy of iron-sulfate treatment. This study explores whether gut microbiota composition differs between anemic children who respond and do not respond to treatment at baseline and posttreatment and if specific microbiota taxa remain associated with response to iron supplementation after controlling for relevant inflammatory and pathogenic variables. METHODS: Data come from 49 pre-school-aged anemic children living in San Juan de Lurigancho, Lima, Peru. We tested for differences in alpha and beta diversity using QIIME 2 and performed differential abundance testing in DESeq2 in R. We ran multivariate regression models to assess associations between abundance of specific taxa and response while controlling for relevant variables in Stata 17. RESULTS: While we found no evidence for gut microbiota diversity associated with child response to iron treatment, we observed several differential abundance patterns between responders and non-responders at both timepoints. Additionally, we present support for a nonzero relationship between lower relative abundance of Barnesiellaceae and response to iron supplementation in samples collected before and after treatment. CONCLUSION: While larger studies and more specific approaches are needed to understand the relationship between microbes and anemia in an epidemiological context, this study suggests that investigating nutritional status and pathogen exposure is key to better understanding the gut microbiome and impact of iron fortification.

Infant eating behaviors and Milk feeding independently predict infant size.

OBJECTIVES: This study investigates the association of infant eating behaviors with infant size, and if those associations are mediated by infant feeding. METHODS: Mothers with infants less than 12 months of age and living in Central North Carolina were enrolled (N = 61). Data were collected at baseline and at 3- and 6-month follow up visits. Modified constructs from the Baby Eating Behavior Questionnaire (BEBQ) and Child Eating Behavior Questionnaire (CEBQ) measured parents' perceptions of infant eating behaviors related to food approach (enjoyment of food, and food responsiveness) and food avoidance (food fussiness, satiety responsiveness, and slowness in eating). Linear mixed effects models tested longitudinal associations among infant eating behavior ratings, infant feeding (breastfeeding intensity, timing of introduction of complementary foods), and anthropometry (weight, length, and weight-for-length z-scores). Path analyses were stratified by age and tested for direct and indirect effects of mothers' ratings of infant eating behaviors and infant feeding on infant anthropometry. RESULTS: Linear mixed models showed that general appetite was associated with higher weight-for-age, and satiety responsiveness was associated with lower length-for-age. Path analyses showed that infant milk feeding did not mediate associations. Breastfeeding intensity was independently associated with lower weight- and length-for-age z-scores. Age at complementary feeding initiation was associated with lower length-for-age z-scores. CONCLUSIONS: Associations between parental perceptions of general appetite, satiety responsiveness, and infant weight and length are observed early in life. These findings suggest that parental perceptions of infant eating behaviors may contribute to the early developmental programming of later health outcomes.

Water Security and Nutrition: Current Knowledge and Research Opportunities.

Water is an essential nutrient that has primarily been considered in terms of its physiological necessity. But reliable access to water in sufficient quantities and quality is also critical for many nutrition-related behaviors and activities, including growing and cooking diverse foods. Given growing challenges to water availability and safety, including climate change, pollution, and infrastructure degradation, a broader conceptualization of water and its diverse uses is needed to sustainably achieve global nutrition targets. Therefore, we review empirical and qualitative evidence describing the linkages between water security (the reliable availability, accessibility, and quality of water for all household uses) and nutrition. Primary linkages include water security for drinking, food production and preparation, infant and young child feeding, and limiting exposure to pathogens and environmental toxins. We then identify knowledge gaps within each linkage and propose a research agenda for studying water security and nutrition going forward, including the concurrent quantification of both food and water availability, accessibility, use, and stability. By making explicit the connections between water security and nutritional well-being, we aim to promote greater collaboration between the nutrition and water, sanitation, and hygiene sectors. Interdisciplinary policies and programs that holistically address the water-nutrition nexus, versus those that focus on water and nutrition independently, are likely to significantly advance our ability to ensure equitable access to healthy foods and safe water for all.

Adiposity and pathogen exposure: An investigation of response to iron supplementation and hypothesized predictors in anemic pre-school-aged children living in a dual burden environment.

OBJECTIVES: Peruvians are experiencing rapid dietary and lifestyle changes, resulting in a phenomenon known as the "dual burden of disease." A common manifestation of the dual burden in individuals is the co-occurrence of overweight and anemia. Despite recent initiatives introduced to address these concerns, rates continue to be public health concerns. This study investigates the relationship between immune activation and lack of response to iron supplementation after 1 month of treatment and explores variation in body fat stores as a potential moderator between immune function and response to treatment. METHODS: Data come from children, aged 2-5 years (n = 50) from a peri-urban community in Lima, Peru. Multivariate logistic regression models were used to explore the associations between response to treatment (Hb > =11.0 g/dl) after 1 month of treatment), markers of immune activation (C-reactive protein [CRP] and reported morbidity symptoms), and measures of body fat (waist-to-height ratio, triceps skinfold thickness, and body mass index [BMI]). RESULTS: We found that high CRP is associated with a lack of response to iron supplementation after 1 month of treatment and that BMI z-score may moderate this association. Generally, larger body size is associated with response to iron supplementation whether or not the children in this sample have high immune activation. However, the probability of anemic children responding to iron supplementation treatment differed across adiposity measures. CONCLUSIONS: Our finding suggesting that adiposity and CRP influence response to iron supplementation, furthers our understanding of the relationship between inflammation and anemia treatment in children and has both theoretical and public health implications.

Child, caretaker, and community: Testing predictors of anemia and response to iron supplementation in Peruvian preschool-aged children.

OBJECTIVES: Despite repeated governmental and nongovernmental interventions, anemia remains a widespread public health concern in Peru. This article examines nutritional and disease factors associated with the prevalence of anemia and response to iron supplementation in Peruvian children, with the aim of understanding the lack of success of national programs. METHODS: Data come from children, aged 2-5 years (n = 102), living in peri-urban Lima. Predictors of anemia and response to iron supplementation were explored at the individual, maternal, household, and environmental levels using logistic regression models, adjusted for clustering by household. RESULTS: Half of the children in this sample were anemic and 50% of the anemic children responded to iron supplementation. We identified several factors that were associated with child anemia status and response to iron supplementation. Lower weight-for-age z-scores and the winter season were strong predictors of child anemia status and nonresponse to iron supplementation. Living with paternal grandparents was protective against anemia and elevated C-reactive protein at the time of the final interview was associated with a lack of response to iron supplementation. CONCLUSIONS: The findings of this study document an association between children's anemia status and their nutritional and ecological environment, highlighting the importance of examining anemia within a specific context to better understand the factors driving this important health problem.

A test for clinal variation in Artemisia californica and associated arthropod responses to nitrogen addition.

The response of plant traits to global change is of fundamental importance to understanding anthropogenic impacts on natural systems. Nevertheless, little is known about plant genetic variation in such responses or the indirect effect of environmental change on higher trophic levels. In a three-year common garden experiment, we grew the shrub Artemisia californica from five populations sourced along a 700 km latitudinal gradient under ambient and nitrogen (N) addition (20 kg N ha-1) and measured plant traits and associated arthropods. N addition increased plant biomass to a similar extent among all populations. In contrast, N addition effects on most other plant traits varied among plant populations; N addition reduced specific leaf area and leaf percent N and increased carbon to nitrogen ratios in the two northern populations, but had the opposite or no effect on the three southern populations. N addition increased arthropod abundance to a similar extent among all populations in parallel with an increase in plant biomass, suggesting that N addition did not alter plant resistance to herbivores. N addition had no effect on arthropod diversity, richness, or evenness. In summary, genetic variation among A. californica populations mediated leaf-trait responses to N addition, but positive direct effects of N addition on plant biomass and indirect effects on arthropod abundance were consistent among all populations.

Preliminary evidence for the feasibility of a stress management intervention for 7- to 12-year-olds with asthma.

OBJECTIVE: Evidence supports a bidirectional relationship between stress and asthma exacerbations in children, suggesting that interventions to reduce stress may improve both psychosocial quality of life and disease course. Here, we examine the feasibility of a stress management intervention for 7- to 12-year-olds with asthma. METHODS: Two trials were conducted. Cohort 1 (n = 11) was recruited from the community and attended intervention sessions at an urban university. Cohort 2 (n = 7) was school based and recruited from an African American charter school. Six individual intervention sessions focused on psychoeducation about asthma, stress, and emotions; problem-solving and coping skills training; and relaxation training paired with physiological feedback. Pre- and post-intervention stress, mood, and lung function data were collected. Satisfaction surveys were administered after intervention completion. RESULTS: The intervention was rated as highly acceptable by participating families. Feasibility was much stronger for the school-based than the university-based recruitment mechanism. Initial efficacy data suggest that both cohorts showed pre- to post-intervention improvements in lung function, perceived stress, and depressed mood. CONCLUSION: Findings provide evidence for the feasibility of offering asthma-related stress management training in a school setting. Initial findings offer support for future, large-scale efficacy studies.

Survivors of childhood cancer and comparison peers: the influence of peer factors on later externalizing behavior in emerging adulthood.

OBJECTIVE: To examine group differences and predictors of externalizing behavior and substance use during the transition to emerging adulthood (i.e., ages 18-25) among survivors of childhood cancer and comparison peers. METHODS: Peer acceptance and social behavior were assessed in classrooms of 55 children (ages 8-15) during cancer treatment. Children with cancer, comparison peers (n = 60), and parents completed measures of externalizing behavior and/or substance use during an initial home visit and soon after participants turned 18. RESULTS: At follow-up, survivors and peers exhibited similar externalizing behaviors and substance use, except peers were more likely to use marijuana. Substance use was associated with earlier peer acceptance and social behavior. Survivors who were older at diagnosis were at greater risk for later externalizing behavior and substance use. CONCLUSIONS: Mean externalizing behaviors and substance use generally fell within normative ranges for both survivors and peers. Some survivors may benefit from interventions to reduce risk behavior.