This study aimed to describe the timing and patterns of pubertal maturation of girls living in rural Bangladesh. Starting in September 2015, a total of 15,320 girls from a birth cohort, aged 9 to 15 ...years at initial encounter, were visited twice at about a one year interval, typically in their birth month. Participants were asked to self-report extent of pubertal maturation, including breast development, pubic hair growth and age at menarche, if applicable. Pubertal stage (abbreviated as B2 and B3-4 for breast development and PH2 and PH3-4 for pubic hair growth) was assigned. Data from both visits were pooled, yielding a total of 29,377 age-related observations per pubertal characteristic. Probit regression models were used to estimate distributions of age at which each stage of pubertal development was attained. Before age 8, <3% of the study population initiated pubertal maturation as indicated by onset of breast development (B2). The median (95% confidence interval) age of B2 and B3-4 was 11.02 (11.00-11.04) and 12.82 (12.80-12.83) years, respectively; and 12.93 (12.91-12.94) and 14.29 (14.27-14.31) years for the onset (PH2) and advanced stage (PH3-4) of pubic hair growth, respectively. Median age at menarche was 13.17 (13.15-13.19) years, with 2.15 years of timespan from B2 to menarche. Girls in rural Bangladesh progressed through puberty following a well-documented sequence of sexual maturation stages. The age at which each pubertal milestone took place was somewhat later, but the tempo from breast development to menarche was comparable to that observed elsewhere. Our findings present a current norm of pubertal maturation in a typical, rural adolescent population in South Asia, which could help inform future studies and interventions to preserve or improve early adolescent health and development.
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.
Questions have been raised about potentially negative effects of antenatal folic acid use in populations with a high prevalence of vitamin B-12 deficiency. Our objective was to examine the ...association between maternal folate and vitamin B-12 status in pregnancy on offspring insulin resistance and examine whether the effects of maternal micronutrient supplementation varied by baseline maternal folate and/or vitamin B-12 status. Pregnant women were cluster randomized to receive daily supplements containing vitamin A alone or with folic acid, folic acid+iron, folic acid+iron+zinc, or a multiple micronutrient. In a subsample (n = 1132), micronutrient status biomarkers were analyzed at baseline and late pregnancy. Children born to the women who participated in the trial were visited at 6-8 y of age. Fasting plasma glucose and insulin were used to estimate insulin resistance using the homeostasis model assessment (HOMA-IR). Children whose mothers were deficient in vitamin B-12 (<148 pmol/L, 27%) during early pregnancy had a 26.7% increase in HOMA-IR (P = 0.02), but there was no association with maternal folate status. Among children born to women who were vitamin B-12 deficient at baseline, the percent difference in HOMA-IR compared to the control group was 15.1% (95% CI: -35.9, 106.4), 4.9% (-41.6, 88.5), 3.3% (-38.4, 73.5), and 18.1% (-29.0, 96.7) in the folic acid, folic acid-iron, folic acid-iron-zinc, and multiple micronutrient supplementation groups, respectively, none of which were significant. Maternal vitamin B-12 deficiency is associated with an elevated risk of insulin resistance, but supplementation with folic acid or other micronutrients led to no significant change in insulin resistance in school-aged offspring.
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.
Animal source foods are rich in multiple nutrients. Regular egg consumption may improve infant growth in low- and middle-income countries.
To assess the impact of daily egg consumption on linear ...growth among 6–12-mo olds in rural Bangladesh.
We conducted a 2 × 4 factorial cluster-randomized controlled trial allocating clusters (n = 566) to treatment for enteric pathogens or placebo and a daily egg, protein supplement, isocaloric supplement, or control. All arms received nutrition education. Here, we compare the effect of the egg intervention versus control on linear growth, a prespecified aim of the trial. Infants were enrolled at 3 mo. We measured length and weight at 6 and 12 mo and visited households weekly to distribute eggs and monitor compliance. We used linear regression models to compare 12-mo mean length, weight, and z-scores for length-for-age (LAZ), weight-for-length, and weight-for-age (WAZ), and log-binomial or robust Poisson regression to compare prevalence of stunting, wasting, and underweight between arms. We used generalized estimating equations to account for clustering and adjusted models for baseline measures of outcomes.
We enrolled 3051 infants (n = 283 clusters) across arms, with complete 6 and 12 mo anthropometry data from 1228 infants (n = 142 clusters) in the egg arm and 1109 infants (n = 141 clusters) in the control. At baseline, 18.5%, 6.0%, and 16.4% were stunted, wasted, and underweight, respectively. The intervention did not have a statistically significant effect on mean LAZ (β: 0.05, 95% confidence interval CI: −0.01, 0.10) or stunting prevalence (β: 0.98, 95% CI: 0.89, 1.13) at 12 mo. Mean weight (β: 0.07 kg, 95% CI: 0.02, 0.11) and WAZ (β: 0.06, 95% CI: 0.02, 0.11) were significantly higher in the egg compared with control arms.
Provision of a daily egg for 6 mo to infants in rural Bangladesh improved ponderal but not linear growth.
NCT03683667, https://clinicaltrials.gov/ct2/show/NCT03683667.
Maternal micronutrient deficiencies may adversely affect fetal and infant health, yet there is insufficient evidence of effects on these outcomes to guide antenatal micronutrient supplementation in ...South Asia.
To assess effects of antenatal multiple micronutrient vs iron-folic acid supplementation on 6-month infant mortality and adverse birth outcomes.
Cluster randomized, double-masked trial in Bangladesh, with pregnancy surveillance starting December 4, 2007, and recruitment on January 11, 2008. Six-month infant follow-up ended August 30, 2012. Surveillance included 127,282 women; 44,567 became pregnant and were included in the analysis and delivered 28,516 live-born infants. Median gestation at enrollment was 9 weeks (interquartile range, 7-12).
Women were provided supplements containing 15 micronutrients or iron-folic acid alone, taken daily from early pregnancy to 12 weeks postpartum.
The primary outcome was all-cause infant mortality through 6 months (180 days). Prespecified secondary outcomes in this analysis included stillbirth, preterm birth (<37 weeks), and low birth weight (<2500 g). To maintain overall significance of α = .05, a Bonferroni-corrected α = .01 was calculated to evaluate statistical significance of primary and 4 secondary risk outcomes (.05/5).
Among the 22,405 pregnancies in the multiple micronutrient group and the 22,162 pregnancies in the iron-folic acid group, there were 14,374 and 14,142 live-born infants, respectively, included in the analysis. At 6 months, multiple micronutrients did not significantly reduce infant mortality; there were 764 deaths (54.0 per 1000 live births) in the iron-folic acid group and 741 deaths (51.6 per 1000 live births) in the multiple micronutrient group (relative risk RR, 0.95; 95% CI, 0.86-1.06). Multiple micronutrient supplementation resulted in a non-statistically significant reduction in stillbirths (43.1 vs 48.2 per 1000 births; RR, 0.89; 95% CI, 0.81-0.99; P = .02) and significant reductions in preterm births (18.6 vs 21.8 per 100 live births; RR, 0.85; 95% CI, 0.80-0.91; P < .001) and low birth weight (40.2 vs 45.7 per 100 live births; RR, 0.88; 95% CI, 0.85-0.91; P < .001).
In Bangladesh, antenatal multiple micronutrient compared with iron-folic acid supplementation did not reduce all-cause infant mortality to age 6 months but resulted in a non-statistically significant reduction in stillbirths and significant reductions in preterm births and low birth weight.
clinicaltrials.gov Identifier: NCT00860470.
Vitamin A deficiency remains a nutritional concern in sub-Saharan Africa. Conventionally bred maize hybrids with high provitamin A carotenoid concentrations may have the potential to improve vitamin ...A status in maize-consuming populations.
We evaluated the efficacy of regular provitamin A carotenoid-biofortified "orange" maizemeal (∼15 μg β-carotene/g) consumption in improving vitamin A status and reducing vitamin A deficiency in children.
This was a cluster-randomized controlled trial in the rural farming district of Mkushi, Zambia. All 4- to 8-y-old children in an ∼400-km(2) area were identified and grouped by proximity into clusters of ∼15-25 children. We randomly assigned clusters to 1) orange maizemeal (n = 25), 2) white maizemeal (n = 25), or 3) a parallel, nonintervention group (n = 14). Children in intervention clusters (n = 1024) received 200 g maizemeal for 6 d/wk over 6 mo; the maizemeal was prepared according to standardized recipes and served in cluster-level kitchens. Staff recorded attendance and leftovers. We collected venous blood before and after the intervention to measure serum retinol, β-carotene, C-reactive protein, and α1-acid glycoprotein.
Intervention groups were comparable at baseline, and vitamin A status was better than anticipated (12.1% deficient on the basis of serum retinol <0.7 μmol/L). Although attendance at meals did not differ (85%), median daily maize intake was higher in white (154 g/d) than in orange (142 g/d) maizemeal clusters. At follow-up, mean serum β-carotene was 0.14 μmol/L (95% CI: 0.09, 0.20 μmol/L) higher in orange maizemeal clusters (P < 0.001), but mean serum retinol (1.00 ± 0.33 μmol/L overall) and deficiency prevalence (17.1% overall) did not differ between arms.
In this marginally nourished population, regular biofortified maizemeal consumption increased serum β-carotene concentrations but did not improve serum retinol. This trial was registered at clinicaltrials.gov as NCT01695148.
ABSTRACT
Background: Childhood undernutrition may have prenatal origins, and the impact of prenatal interventions on postnatal growth is not well known.
Objective: We assessed the effects of prenatal ...multiple micronutrient (MM) supplementation on child growth and cognitive development.
Design: In a cluster-randomized controlled trial in rural Bangladesh, prenatal MM supplementation compared with iron-folic acid (IFA) supplementation was examined for its impact on growth assessed longitudinally from birth up to 24 mo of age (n = 8529) and, in a subsample (n = 734), on cognitive function at 24 mo of age by use of the Bayley scales of infant and toddler development–third edition test.
Results: Prevalence of stunting at birth length for age z score (LAZ): <−2 was 31.9% in the MM and 35.7% in the IFA groups (P < 0.001); however, LAZ increased during the first 3–4 mo in both groups. With the use of a linear random-effects model, prenatal MM-exposed children sustained a higher mean predicted LAZ of ∼0.10 at 1 and 3 mo and 0.06 at 6 mo of age compared with children in the IFA group. Supplementation reduced the prevalence of stunting at 1 (RR: 0.95; 95% CI: 0.92, 0.98) and 3 (RR: 0.91; 95% CI: 0.88, 0.94) mo of age. Differences between groups were absent by 6, 12, and 24 mo of age, when nearly 50% of children had stunted growth. Ponderal and linear growth velocities were somewhat slower from 3 to 12 mo of age in the MM group than in the IFA group, but not from 12 to 24 mo of age. There was no difference between groups on composite scores of cognition, language, and motor performance at 24 mo of age.
Conclusions: In this Bangladeshi trial, maternal pre- and postnatal MM supplementation resulted in improvements in LAZ and reduction in stunting through 3 mo of age, but not thereafter and had no impact on cognitive and motor function at 2 y. This trial was registered at clinicaltrials.gov as NCT000860470.
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.
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