Usha Ramakrishnan

Anaemia in low-income and middle-income countries

Anaemia affects a quarter of the global population, including 293 million (47%) children younger than 5 years and 468 million (30%) non-pregnant women. In addition to anaemias adverse health consequences, the economic effect of anaemia on human capital results in the loss of billions of dollars annually. In this paper, we review the epidemiology, clinical assessment, pathophysiology, and consequences of anaemia in low-income and middle-income countries. Our analysis shows that anaemia is disproportionately concentrated in low socioeconomic groups, and that maternal anaemia is strongly associated with child anaemia. Anaemia has multifactorial causes involving complex interaction between nutrition, infectious diseases, and other factors, and this complexity presents a challenge to effectively address the population determinants of anaemia. Reduction of knowledge gaps in research and policy and improvement of the implementation of effective population-level strategies will help to alleviate the anaemia burden in low-resource settings.

Prevalence of micronutrient malnutrition worldwide.

Recent estimates indicate that globally over two billion people are at risk for vitamin A, iodine, and/or iron deficiency, in spite of recent efforts in the prevention and control of these deficiencies. The prevalence is especially high in Southeast Asia and sub-Saharan Africa, and pregnant women and young children are at greatest risk. Other micronutrient deficiencies of public health concern include zinc, folate, and the B vitamins. However, there is limited data on the actual prevalence of these deficiencies. Finally, in many settings, more than one micronutrient deficiency exists, suggesting the need for simple approaches that evaluate and address multiple micronutrient malnutrition.

Maternal Influenza Immunization and Reduced Likelihood of Prematurity and Small for Gestational Age Births: A Retrospective Cohort Study

In an analysis of surveillance data from the state of Georgia (US), Saad Omer and colleagues show an association between receipt of influenza vaccination among pregnant women and reduced risk of premature births.

Effect of Women's Nutrition before and during Early Pregnancy on Maternal and Infant Outcomes: A Systematic Review

Current understanding of biologic processes indicates that womens nutritional status before and during early pregnancy may play an important role in determining early developmental processes and ensuring successful pregnancy outcomes. We conducted a systematic review of the evidence for the impact of maternal nutrition before and during early pregnancy (<12 weeks gestation) on maternal, neonatal and child health outcomes and included 45 articles (nine intervention trials and 32 observational studies) that were identified through PubMed and EMBASE database searches and examining review articles. Intervention trials and observational studies show that periconceptional (<12 weeks gestation) folic acid supplementation significantly reduced the risk of neural tube defects. Observational studies suggest that preconceptional and periconceptional intake of vitamin and mineral supplements is associated with a reduced risk of delivering offspring who are low birthweight and/or small-for-gestational age (SGA) and preterm deliveries (PTD). Some studies report that indicators of maternal prepregnancy size, low stature, underweight and overweight are associated with increased risks of PTD and SGA. The available data indicate the importance of womens nutrition prior to and during the first trimester of pregnancy, but there is a need for well-designed prospective studies and controlled trials in developing country settings that examine relationships with low birthweight, SGA, PTD, stillbirth and maternal and neonatal mortality. The knowledge gaps that need to be addressed include the evaluation of periconceptional interventions such as food supplements, multivitamin-mineral supplements and/or specific micronutrients (iron, zinc, iodine, vitamin B-6 and B-12) as well as the relationship between measures of prepregnancy body size and composition and maternal, neonatal and child health outcomes.

Micronutrients and pregnancy outcome: A review of the literature☆

There is considerable evidence supporting the role of various micronutrients in determining pregnancy outcomes such as low birth weight and prematurity. While some nutrients have been studied extensively (e.g.:calcium, zinc) much less is known about others (e.g.:vitamin B-complex). Methodologically, there is considerable variation in the types of study design ranging from cross-sectional studies to well designed randomized placebo-controlled trials (RCTs) most of which were conducted in developing countries among women who were not deficient and therefore less likely to benefit from the interventions. Inadequate sample size was another problem in many studies. The key conclusions of this review of the literature are 1) there is strong evidence primarily from developed countries that zinc, calcium and magnesium supplementation could improve birth weight, prematurity and hypertension particularly in high risk groups 2) folic acid can prevent neural tube defects, but the evidence on whether iron/and or folic acid supplements reduce the prevalence of low birth weight (LBW), prematurity and maternal mortality is limited 3) Severe iodine deficiency results in increase pregnancy loss, mental retardation and cretinism, but less is known for other outcomes especially in the case of marginal iodine deficiency 4) vitamin A supplements might reduce maternal mortality and perhaps LBW 5) vitamin C may play a role in the etiology of prematurity and 6) the B-complex vitamins, copper and selenium may have a role but very few experimental studies have been conducted to date. Most importantly, although there is evidence of interactions among several micronutrients at the metabolic level, very little is known about the significance of interactions for pregnancy outcomes. There is a need for well designed RCTs that will examine the role of selected nutrient interactions and multi vitamin-mineral supplements in improving pregnancy outcomes especially in developing countries where nutrient deficiencies do not occur in isolation and multiple micronutrients deficiencies are common.

Risk of childhood undernutrition related to small-for-gestational age and preterm birth in low- and middle-income countries

BACKGROUND Low- and middle-income countries continue to experience a large burden of stunting; 148 million children were estimated to be stunted, around 30-40% of all children in 2011. In many of these countries, foetal growth restriction (FGR) is common, as is subsequent growth faltering in the first 2 years. Although there is agreement that stunting involves both prenatal and postnatal growth failure, the extent to which FGR contributes to stunting and other indicators of nutritional status is uncertain. METHODS Using extant longitudinal birth cohorts (n=19) with data on birthweight, gestational age and child anthropometry (12-60 months), we estimated study-specific and pooled risk estimates of stunting, wasting and underweight by small-for-gestational age (SGA) and preterm birth. RESULTS We grouped children according to four combinations of SGA and gestational age: adequate size-for-gestational age (AGA) and preterm; SGA and term; SGA and preterm; and AGA and term (the reference group). Relative to AGA and term, the OR (95% confidence interval) for stunting associated with AGA and preterm, SGA and term, and SGA and preterm was 1.93 (1.71, 2.18), 2.43 (2.22, 2.66) and 4.51 (3.42, 5.93), respectively. A similar magnitude of risk was also observed for wasting and underweight. Low birthweight was associated with 2.5-3.5-fold higher odds of wasting, stunting and underweight. The population attributable risk for overall SGA for outcomes of childhood stunting and wasting was 20% and 30%, respectively. CONCLUSIONS This analysis estimates that childhood undernutrition may have its origins in the foetal period, suggesting a need to intervene early, ideally during pregnancy, with interventions known to reduce FGR and preterm birth.

Effects of micronutrients on growth of children under 5 y of age: meta-analyses of single and multiple nutrient interventions

BACKGROUND Micronutrient interventions have received much attention as a cost-effective and promising strategy to improve child health, but their roles in improving child growth remain unclear. OBJECTIVE Meta-analyses of randomized controlled trials were conducted to evaluate the effect of micronutrient interventions on the growth of children aged <5 y old. DESIGN Eligible studies were identified by PubMed database searches and other methods. Weighted mean effect sizes and 95% CIs were calculated for changes in height, weight, and weight-for-height z scores (WHZ) by using random-effect models. Tests for publication bias were done by using funnel plots, heterogeneity, and stratified analyses by predefined characteristics. RESULTS Interventions including iron (n = 27) or vitamin A (n = 17) only had no significant effects on growth. Interventions including zinc only (n = 43) had a small positive effect (effect size = 0.06; 95% CI: 0.006, 0.11) on change in WHZ but no significant effect on height or weight gain. Multiple micronutrient interventions (n = 20) improved linear growth (0.09; 95% CI: 0.008, 0.17). CONCLUSIONS Our findings confirm earlier results of no benefits for interventions including iron and vitamin A only but differ from the earlier meta-analysis that found improvements in linear growth for zinc only interventions. This may be due to the improved nutritional status of children in the more recent studies. Multiple micronutrient interventions improve linear growth, but the benefits are small. Other strategies are needed to prevent stunting.

Effect of Zinc on Efficacy of Iron Supplementation in Improving Iron and Zinc Status in Women

Iron and zinc may interact in micronutrient supplements and thereby decrease efficacy. We investigated interactive effects of combined zinc and iron supplementation in a randomized controlled trial conducted in 459 Guatemalan women. Four groups were supplemented for 12 weeks: (1) weekly iron and folic acid (IFA); (2) weekly IFA and 30 mg zinc; (3) daily IFA; (4) daily IFA and 15 mg zinc. Effects were assessed by generalized linear regression. Baseline hemoglobin (Hb) concentration was 137.4 ± 15.5 g/L, 13% were anemic and 54% had zinc deficiency. Hb cconcentrations were similar by supplement type, but Hb concentrations improved significantly in anemic women at baseline (increase of 21.8 g/L). Mean percentage changes in serum ferritin were significantly higher in daily compared to weekly supplemented groups (86% versus 32%). The addition of zinc to IFA supplements had no significant impact on iron or zinc status. In conclusion, adding zinc to IFA supplements did not modify efficacy on iron status or improve zinc status, but daily supplementation was more efficacious than weekly in improving iron stores.

Effects of Docosahexaenoic Acid Supplementation During Pregnancy on Gestational Age and Size at Birth: Randomized, Double-Blind, Placebo-Controlled Trial in Mexico

Background The need for omega-3 fatty acids, especially docosahexaenoic acid (DHA), during pregnancy has received much attention, but evidence of effects on birth outcomes is limited. Objective To evaluate whether prenatal DHA supplementation increases gestational age and birth size. Methods We conducted a double-blind, randomized, placebo-controlled trial in Cuernavaca, Mexico. We randomly assigned 1,094 pregnant women (18 to 35 years of age; median DHA dietary intake, 55 mg/day) to 400 mg/day of algal DHA or placebo from 18 to 22 weeks of gestation through delivery. Birth outcomes (968 live births and 5 stillbirths) were ascertained from hospital records within 24 hours of delivery. Results Intention-to-treat analysis showed no differences between the control and DHA group (all p > .05) in mean gestational age (39.1 + 1.7 and 39.0 ± 1.9 weeks, respectively), weight (3.20 + 0.47 and 3.21 ± 0.45 kg, respectively), length (50.3 ± 2.7 and 50.3 ± 2.3 cm, respectively) and head circumference (34.3 ± 1.8 and 34.3 ± 1.5 cm, respectively) at birth. Offspring of supplemented primigravidae (n = 370) were heavier (difference, 99.4 g; 95% CI, 5.5 to 193.4) and had larger head circumferences (difference, 0.5 cm; 95% CI, 0.1 to 0.9) than controls; the differences in multigravidae (n = 603) were −53.3 g (95% CI, −126.8 to 20.2) and −0.2 cm (95% CI, −0.4 to 0.1), respectively (p < .05 for heterogeneity). Conclusions Prenatal DHA supplementation of primigravid women may result in increased birth size in a population where dietary DHA intakes are very low. Benefits of the intervention on infant health and neurodevelopment are under study.

Impacts of domestic violence on child growth and nutrition: a conceptual review of the pathways of influence.

Domestic violence against women is a global problem, and young children are disproportionate witnesses. Childrens exposure to domestic violence (CEDV) predicts poorer health and development, but its effects on nutrition and growth are understudied. We propose a conceptual framework for the pathways by which domestic violence against mothers may impair child growth and nutrition, prenatally and during the first 36 months of life. We synthesize literatures from multiple disciplines and critically review the evidence for each pathway. Our review exposes gaps in knowledge and opportunities for research. The framework also identifies interim strategies to mitigate the effects of CEDV on child growth and nutrition. Given the global burden of child malnutrition and its long-term effects on human-capital formation, improving child growth and nutrition may be another reason to prevent domestic violence and its cascading after-effects.