Previously, we showed that antenatal micronutrient supplementation increases birth weight in a malnourished rural South Asian setting, but the long-term effects are unknown. Between 1999 and 2001, ...pregnant women were sector-randomized to receive from early pregnancy through 3 mo postpartum daily micronutrient supplements containing either vitamin A alone as the control or with folic acid; folic acid+iron; folic acid+iron+zinc; or a multiple micronutrient supplement that included the above nutrients plus 11 others. From 2006 to 2008, 3524 children (93% of surviving children) were revisited between the ages of 6 and 8 y. Blood pressure, BMI, waist circumference, glycated hemoglobin, cholesterol, triglycerides, glucose, insulin, and the urinary microalbumin:creatinine ratio were assessed among children. Insulin resistance was estimated using the homeostasis model assessment (HOMA) and metabolic syndrome was defined using a modified National Cholesterol Education Program definition. None of the micronutrient supplement combinations affected blood pressure, cholesterol, triglycerides, glucose, insulin, or HOMA. There was a reduced risk of microalbuminuria (greater-than-or-equal3.40 mg/mmol creatinine) in the folic acid odds ratio (OR), 0.56; 95%CI, 0.33-0.93; P = 0.02) and folic acid+iron+zinc (OR, 0.53; CI, 0.32-0.89; P = 0.02) groups and a reduced risk of metabolic syndrome in the folic acid group (OR, 0.63; CI, 0.41-0.97; P = 0.03). Maternal supplementation with folic acid or folic acid+iron+zinc reduced the risk of kidney dysfunction and, to some extent, metabolic syndrome among children at 6-8 y of age. Supplementation with multiple micronutrients had no such affect. Future follow-up studies are needed to examine long-term supplementation effects on risk of chronic diseases in adults.
Inflammation is a condition stemming from complex host defense and tissue repair mechanisms, often simply characterized by plasma levels of a single acute reactant. We attempted to identify candidate ...biomarkers of systemic inflammation within the plasma proteome. We applied quantitative proteomics using isobaric mass tags (iTRAQ) tandem mass spectrometry to quantify proteins in plasma of 500 Nepalese children 6-8 years of age. We evaluated those that co-vary with inflammation, indexed by α-1-acid glycoprotein (AGP), a conventional biomarker of inflammation in population studies. Among 982 proteins quantified in >10% of samples, 99 were strongly associated with AGP at a family-wise error rate of 0.1%. Magnitude and significance of association varied more among proteins positively (n = 41) than negatively associated (n = 58) with AGP. The former included known positive acute phase proteins including C-reactive protein, serum amyloid A, complement components, protease inhibitors, transport proteins with anti-oxidative activity, and numerous unexpected intracellular signaling molecules. Negatively associated proteins exhibited distinct differences in abundance between secretory hepatic proteins involved in transporting or binding lipids, micronutrients (vitamin A and calcium), growth factors and sex hormones, and proteins of largely extra-hepatic origin involved in the formation and metabolic regulation of extracellular matrix. With the same analytical approach and the significance threshold, seventy-two out of the 99 proteins were commonly associated with CRP, an established biomarker of inflammation, suggesting the validity of the identified proteins. Our findings have revealed a vast plasma proteome within a free-living population of children that comprise functional biomarkers of homeostatic and induced host defense, nutrient metabolism and tissue repair, representing a set of plasma proteins that may be used to assess dynamics and extent of inflammation for future clinical and public health application.
Isobaric tags for relative and absolute quantitation (iTRAQ) is a prominent mass spectrometry technology for protein identification and quantification that is capable of analyzing multiple samples in ...a single experiment. Frequently, iTRAQ experiments are carried out using an aliquot from a pool of all samples, or “masterpool”, in one of the channels as a reference sample standard to estimate protein relative abundances in the biological samples and to combine abundance estimates from multiple experiments. In this manuscript, we show that using a masterpool is counterproductive. We obtain more precise estimates of protein relative abundance by using the available biological data instead of the masterpool and do not need to occupy a channel that could otherwise be used for another biological sample. In addition, we introduce a simple statistical method to associate proteomic data from multiple iTRAQ experiments with a numeric response and show that this approach is more powerful than the conventionally employed masterpool-based approach. We illustrate our methods using data from four replicate iTRAQ experiments on aliquots of the same pool of plasma samples and from a 406-sample project designed to identify plasma proteins that covary with nutrient concentrations in chronically undernourished children from South Asia.
Impaired dark adaptation is an early functional indicator of vitamin A deficiency that may be prevented by regular dietary intake of foods containing provitamin A carotenoids.
We tested the impact of ...provitamin A carotenoid-biofortified maize consumption (∼15 μg β-carotene/g) on dark adaptation in Zambian children.
We used a cluster-randomized trial of children aged 4-8 y (n = 1024) in Mkushi District, Zambia, and compared the regular consumption (2 meals/d, 6 d/wk for 6 mo) of biofortified orange maize (OM) to white maize (WM). The primary outcome was the serum retinol response. In a random sample (n = 542), we used a digital pupillometer to test pre- and postintervention responses to graded light stimuli (-2.9 to 0.1 log cd/m
) in a dark-adapted state.
At baseline, 11.7% of the children had serum retinol <0.7 μmol/L, 14.4% had impaired dark adaptation (pupillary threshold ≥ -1.11 log cd/m
), and 2.3% had night blindness. The mean ± SD pupillary responsiveness to light stimuli was poorer at baseline in the OM group (16.1% ± 6.6%) than the WM group (18.1% ± 6.4%) (P = 0.02) but did not differ at follow-up (OM: 17.6% ± 6.5%; WM: 18.3% ± 6.5%). Among children with serum retinol <1.05 μmol/L at baseline, there was greater improvement in pupillary responsiveness in the OM group (2.2%; 95% CI: 0.1%, 4.3%) than the WM group (0.2%; 95% CI: -1.1%, 1.5%; P = 0.01), but there were no differences in children with adequate baseline status. We found no effect of treatment on pupillary threshold or night blindness.
The regular consumption of provitamin A carotenoid-biofortified maize increased pupillary responsiveness among children with marginal or deficient vitamin A status, providing evidence of a functional benefit to consuming this biofortified crop. This trial was registered at clinicaltrials.gov as NCT01695148.
ABSTRACT
Objectives:
Environmental enteric dysfunction (EED) may inhibit growth and development in low‐ and middle‐income countries, but available assessment methodologies limit its study. In rural ...Bangladesh, we measured EED using the widely used lactulose mannitol ratio (L:M) test and a panel of intestinal and systemic health biomarkers to evaluate convergence among biomarkers and describe risk factors for EED.
Methods:
In 539 18‐month‐old children finishing participation in a randomized food supplementation trial, serum, stool, and urine collected after lactulose and mannitol dosing were analyzed for biomarkers of intestinal absorption, inflammation, permeability and repair, and systemic inflammation. EED scores for each participant were developed using principal component analysis and partial least squares regression. Associations between scores and L:M and with child sociodemographic and health characteristics were evaluated using regression analysis.
Results:
EED prevalence (L:M > 0.07) was 39.0%; 60% had elevated acute phase proteins (C‐reactive protein >5 mg/L or α‐1 acid glycoprotein >100 mg/dL). Correlations between intestinal biomarkers were low, with the highest between myeloperoxidase and α‐1 antitrypsin (r = 0.33, P < 0.01), and biomarker values did not differ by supplementation history. A 1‐factor partial least squares model with L:M as the dependent variable explained only 8.6% of L:M variability. In adjusted models, L:M was associated with child sex and socioeconomic status index, whereas systemic inflammation was predicted mainly by recent illness, not EED.
Conclusions:
Impaired intestinal health is widespread in this setting of prevalent stunting, but a panel of serum and stool biomarkers demonstrated poor agreement with L:M. Etiologies of intestinal and systemic inflammation are likely numerous and complex in resource‐poor settings, underscoring the need for a better case definition with corresponding diagnostic methods to further the study of EED.
Four fortified complementary food supplements (CFSs) in a randomized controlled trial (RCT) were found to improve childhood linear growth in rural Bangladesh. We hypothesized children receiving these ...supplements would have improved micronutrient status.
In the RCT, we assessed hemoglobin and serum ferritin, retinol, zinc, C-reactive protein (CRP), and α-1-acid glycoprotein (AGP) at endline (18 mo) in a subsample of children (
= 752). The impact of supplementation on mean concentrations and the prevalence of nutrient deficiency and inflammation were evaluated using adjusted generalized estimating equation (GEE) linear and log-binomial regression models.
In the control arm at age 18 months, 13% of children were anemic (hemoglobin < 110 g/L), and 6% were iron (inflammation-adjusted ferritin < 12 μg/L), 8% vitamin A (inflammation-adjusted retinol < 0.70 μmol/L), and 5% zinc (zinc < 9.9 μmol/L) deficient. The prevalence of inflammation by CRP (>5 mg/L) and AGP (>1 g/L) was 23% and 66%, respectively, in the control group. AGP trended lower in CFS groups (
= 0.04), while CRP did not. Mean ferritin (
< 0.001) and retinol (
= 0.007) were higher in all supplemented groups relative to control, whereas hemoglobin improved with two of the four CFSs (
= 0.001), and zinc was equal or lower in supplemented groups relative to control (
= 0.017).
CFSs improved iron status and vitamin A concentrations and lowered inflammation in a context of low underlying nutrient deficiency but high inflammation.
Arsenic methylation converts inorganic arsenic (iAs) to monomethyl (MMA) and dimethyl (DMA) arsenic compounds. Body mass index (BMI) has been positively associated with arsenic methylation efficiency ...(higher DMA%) in adults, but evidence in pregnancy is inconsistent. We estimated associations between anthropometric measures and arsenic methylation among pregnant women in rural northern Bangladesh.
We enrolled pregnant women (n = 784) (median IQR gestational week: 14 13, 15) in Gaibandha District, Bangladesh from 2018 to 2019. Anthropometric measures were BMI, subscapular and triceps skinfold thicknesses, and mid-upper arm circumference (MUAC), fat area (MUAFA), and muscle area (MUAMA). Arsenic methylation measures were urinary iAs, MMA, and DMA divided by their sum and multiplied by 100 (iAs%, MMA%, and DMA%), primary methylation index (MMA/iAs; PMI), and secondary methylation index (DMA/MMA; SMI). In complete cases (n = 765 97.6%), we fitted linear, beta, and Dirichlet regression models to estimate cross-sectional differences in iAs%, MMA%, DMA%, PMI, and SMI per IQR-unit difference in each anthropometric measure, adjusting for drinking water arsenic, age, gestational age, education, living standards index, and plasma folate, vitamin B12, and homocysteine.
Median (IQR) BMI, subscapular skinfold thickness, triceps skinfold thickness, MUAC, MUAFA, and MUAMA were 21.5 (19.4, 23.8) kg/m2, 17.9 (13.2, 24.2) mm, 14.2 (10.2, 18.7) mm, 25.9 (23.8, 28.0) cm, 15.3 (10.5, 20.3) cm2, and 29.9 (25.6, 34.2) cm2, respectively. Median (IQR) iAs%, MMA%, DMA%, PMI, and SMI were 12.0 (9.3, 15.2)%, 6.6 (5.3, 8.3)%, 81.0 (77.1, 84.6)%, 0.6 (0.4, 0.7), and 12.2 (9.3, 15.7), respectively. In both unadjusted and adjusted linear models, all anthropometric measures were negatively associated with iAs%, MMA%, and PMI and positively associated with DMA% and SMI. For example, fully adjusted mean differences (95% CI) in DMA% per IQR-unit difference in BMI, subscapular skinfolds thickness, triceps skinfold thickness, MUAC, MUAFA, and MUAMA were 1.72 (1.16, 2.28), 1.58 (0.95, 2.21), 1.74 (1.11, 2.37), 1.45 (0.85, 2.06), 1.70 (1.08, 2.31), and 0.70 (0.13, 1.27) pp, respectively.
Anthropometric measures were positively associated with arsenic methylation efficiency among pregnant women in the early second trimester.
•Anthropometric measures were positively associated with arsenic methylation efficiency in pregnancy.•Associations were independent of plasma biomarkers of micronutrient status.•Results suggest adiposity was more relevant than lean mass.
Integrated nutrition and health programs seek to reduce undernutrition by educating child caregivers about infant feeding and care. Data on the quality of program implementation and consequent ...effects on infant feeding practices are limited. This study evaluated the effectiveness of enhancing a nutrition and health program on breastfeeding and complementary-feeding practices in rural India.
Utilizing a quasi-experimental design, one of the implementing districts of a Cooperative for Assistance and Relief Everywhere (CARE) nutrition and health program was randomly selected for enhanced services and compared with a district receiving the Government of India's standard nutrition and health package alone. A cohort of 942 mother-child dyads was longitudinally followed from birth to 18 months. In both districts, the evaluation focused on responses to services delivered by community-based nutrition and health care providers anganwadi workers (AWWs) and auxiliary nurse midwives (ANMs).
The CARE enhanced program district showed an improvement in program coverage indicators (e.g., contacts, advice) through outreach visits by both AWWs (28.8-59.8% vs. 0.7-12.4%; all p<0.05) and ANMs (8.6-46.2% vs. 6.1-44.2%; <0.05 for ages ≥6 months). A significantly higher percentage of child caregivers reported being contacted by the AWWs in the CARE program district (20.5-45.6% vs. 0.3-21.6%; p<0.05 for all ages except at 6months). No differences in ANM household contacts were reported. Overall, coverage remained low in both areas. Less than a quarter of women received any infant feeding advice in the intervention district. Earlier and exclusive breastfeeding improved with increasing number or quality of visits by either level of health care provider (OR: 2.04-3.08, p = <0.001), after adjusting for potentially confounding factors. Socio-demographic indicators were the major determinants of exclusive breastfeeding up to 6 month and age-appropriate complementary-feeding practices thereafter in the program-enhanced but not comparison district.
An enhanced nutrition and health intervention package improved program exposure and associated breastfeeding but not complementary-feeding practices, compared to standard government package.
ClinicalTrials.gov NCT00198835.
Eggs are nutrient-rich. Strengthening evidence of the impact of egg consumption on dietary quality can inform complementary feeding guidance.
We aimed to assess the effect of an egg intervention on ...dietary intakes among infants aged 6–12 mo in rural Bangladesh.
We conducted a cluster-randomized controlled trial allocating clusters (n = 566) to enteric pathogen control or placebo treatment, with daily provision of a protein-rich meal, isocaloric meal, egg, or control. Nutrition education was provided to all arms. Our focus here is on the egg and control arms. Infants were enrolled at 3 mo. From 6 mo, we visited households weekly to distribute eggs and measure compliance. A semistructured feeding questionnaire assessed 24-h intake at 6, 9, and 12 mo. Assessments were repeated in ∼10% of subjects 2–29 d later. Using NCI SAS macros, we estimated usual intake distributions for energy, protein, fat, and 18 micronutrients and the proportion meeting intake recommendations. We compared the outcomes between the arms using clustered bootstrapping.
Data were available from 757 infants (137 clusters) and 943 infants (141 clusters) in the egg and control arms, respectively. In the egg arm compared with the control arm, the mean usual intakes were higher for energy (610 compared with 602 kcal/d, 9 mo; 669 compared with 658 kcal/d, 12 mo), crude protein (2.2 compared with 1.7 g/(kg·d), 9 mo; 2.4 compared with 1.9 g/(kg·d), 12 mo), available protein (2.0 compared with 1.6 g/(kg·d), 9 mo; 2.1 compared with 1.8 g/(kg·d), 12 mo), and for 13 and 14 micronutrients at 9 and 12 mo, respectively. The proportion meeting intake recommendations for most micronutrients was higher in the egg arm but remained <50% for 15 and 13 micronutrients at 9 and 12 mo, respectively.
Daily egg consumption improved dietary intakes among Bangladeshi infants, but was insufficient to meet multiple micronutrient intake recommendations, demonstrating the need to be coupled with other strategies.