Adjusting ferritin concentrations for inflammation: Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project

Multiple micronutrient status and predictors of anemia in young children aged 12-23 months living in New Delhi, India

Anemia has been identified as a severe public health concern among young children in India, however, information on the prevalence of anemia attributed to micronutrient deficiencies is lacking. We aimed to assess multiple micronutrient status (iron, zinc, selenium, vitamin A, vitamin D, folate and vitamin B12) in young Indian children and to investigate the role of these seven micronutrients and other non-nutritional factors on hemoglobin concentrations and anemia. One-hundred and twenty children aged 12 to 23 months were included in a cross-sectional nutritional assessment survey, of which 77 children provided a blood sample. Hemoglobin (Hb), serum ferritin, soluble transferrin receptor (sTfR), total body iron, zinc, selenium, retinol binding protein (RBP), folate, vitamin B12 and 25-hydroxyvitamin D (25(OH)D) were measured, and adjusted for inflammation using C-reactive protein (CRP) and α-1-acid glycoprotein (AGP), where appropriate. Predictors for hemoglobin and anemia were identified in multiple regression models. Most of the children were classified as anemic, of which 86 to 93% was associated with iron deficiency depending on the indicator applied. Deficiencies of folate (37%), and notably vitamin D (74%) were also common; fewer children were classified with deficiencies of vitamin B12 (29%), zinc (25%), and vitamin A (17%) and selenium deficiency was nearly absent. Multiple micronutrient deficiencies were common with over half (57%) deficient in three or more micronutrients, and less than 10% of children were classified with adequate status for all the micronutrients measured. Iron status was found to be the only nutritional factor statistically significantly inversely associated with anemia (P = 0.003) in multivariate analysis after controlling for sex. A coordinated multi-micronutrient program is urgently needed to combat the co-existing micronutrient deficiencies in these young children to improve micronutrient status and reduce the high burden of childhood anemia.

Malaria early in the first pregnancy: Potential impact of iron status

BACKGROUND & AIMS

Low iron stores may protect from malaria infection, therefore improving iron stores in early pregnancy in line with current recommendations could increase malaria susceptibility. To test this hypothesis we compared iron biomarkers and red cell indices in nulliparae and primigravidae who participated in a randomized controlled trial of long-term weekly iron supplementation.

METHODS

Cross-sectional and longitudinal data analysis from a randomized controlled trial of long-term weekly iron supplementation in rural Burkina Faso. Malaria parasitaemia was monitored and biomarkers and red cell indices measured at study end-points: plasma ferritin, transferrin receptor (sTfR), zinc protoporphyrin, hepcidin, sTfR/log₁₀ ferritin ratio, body iron, haemoglobin, red cell distribution width; mean corpuscular haemoglobin concentration/volume, and C-reactive protein. Correlation coefficients between biomarkers and red cell indices were determined. A regression correction approach based on ferritin was used to estimate iron body stores, allowing for inflammation. Body iron differences were compared between nulliparae and primigravidae, and the association determined of iron biomarkers and body iron stores with malaria.

RESULTS

Iron and haematological indices of 972 nulliparae (mean age 16.5 years) and 314 primigravidae (median gestation 18 weeks) were available. Malaria prevalence was 54.0% in primigravidae and 41.8% in nulliparae (relative risk 1.28, 95% CI 1.13-1.45, P < 0.001), anaemia prevalence 69.7% and 43.4% (P < 0.001), and iron deficient erythropoiesis (low body iron) 8.0% and 11.7% (P = 0.088) respectively. Unlike other biomarkers the sTfR/log₁₀ ferritin ratio showed no correlation with inflammation as measured by CRP. Most biomarkers indicated reduced iron deficiency in early pregnancy, with the exception of haemoglobin. Body iron increased by 0.6-1.2 mg/kg in early gestation, did not differ by malaria status in nulliparae, but was higher in primigravidae with malaria (6.5 mg/kg versus 5.0 mg/kg; relative risk 1.53, 95% CI 0.67-2.38, P < 0.001).

CONCLUSION

In primigravidae, early pregnancy haemoglobin was not a good indicator of requirement for iron supplementation, which could be detrimental given the association of better iron status with increased malaria infection.

TRIAL REGISTRATION

clinicaltrials.gov:NCT01210040. Until placed in a public repository, data relating to the current study can be requested from the corresponding author and will be made available following an end user data agreement and sponsor approval.

The Effect of Vitamin D Supplementation on Hepcidin, Iron Status, and Inflammation in Pregnant Women in the United Kingdom

Iron and vitamin D deficiencies are common during pregnancy. Our aim was to identify whether antenatal vitamin D₃ supplementation affects iron status (via hepcidin suppression) and/or inflammation. Using a subset of the UK multicenter Maternal Vitamin D Osteoporosis Study (MAVIDOS)-a double-blinded, randomized, placebo-controlled trial (ISRCTN82927713; EudraCT2007-001716-23)-we performed a secondary laboratory analysis. Women with blood samples from early and late pregnancy (vitamin D₃ (1000 IU/day from ~14 weeks gestation n = 93; placebo n = 102) who gave birth in the springtime (March⁻May) were selected as we anticipated seeing the greatest treatment group difference in change in 25-hydroxyvitamin D (25OHD) concentration. Outcomes were hepcidin, ferritin, C-reactive protein, and α1-acid glycoprotein concentration in late pregnancy (25OHD concentration was measured previously). By late pregnancy, 25OHD concentration increased by 17 nmol/L in the vitamin D₃ group and decreased by 11 nmol/L in the placebo group; hepcidin, ferritin, and inflammatory markers decreased but no treatment group differences were seen. In late pregnancy, positive relationships between 25OHD and hepcidin and 25OHD and ferritin in the placebo group were observed but not in the treatment group (group × 25OHD interaction, p < 0.02). Vitamin D₃ supplementation had no effect on hepcidin, ferritin, or inflammatory status suggesting no adjunctive value of vitamin D₃ in reducing rates of antenatal iron deficiency.

Effects of lipid-based nutrient supplements and infant and young child feeding counseling with or without improved water, sanitation, and hygiene (WASH) on anemia and micronutrient status: results from 2 cluster-randomized trials in Kenya and Bangladesh

Background

Anemia in young children is a global health problem. Risk factors include poor nutrient intake and poor water quality, sanitation, or hygiene.

Objective

We evaluated the effects of water quality, sanitation, handwashing, and nutrition interventions on micronutrient status and anemia among children in rural Kenya and Bangladesh.

Design

We nested substudies within 2 cluster-randomized controlled trials enrolling pregnant women and following their children for 2 y. These substudies included 4 groups: water, sanitation, and handwashing (WSH); nutrition (N), including lipid-based nutrient supplements (LNSs; ages 6-24 mo) and infant and young child feeding (IYCF) counseling; WSH+N; and control. Hemoglobin and micronutrient biomarkers were measured after 2 y of intervention and compared between groups using generalized linear models with robust SEs.

Results

In Kenya, 699 children were assessed at a mean ± SD age of 22.1 ± 1.8 mo, and in Bangladesh 1470 participants were measured at a mean ± SD age of 28.0 ± 1.9 mo. The control group anemia prevalences were 48.8% in Kenya and 17.4% in Bangladesh. There was a lower prevalence of anemia in the 2 N intervention groups in both Kenya [N: 36.2%; prevalence ratio (PR): 0.74; 95% CI: 0.58, 0.94; WSH+N: 27.3%; PR: 0.56; 95% CI: 0.42, 0.75] and Bangladesh (N: 8.7%; PR: 0.50; 95% CI: 0.32, 0.78; WSH+N: 7.9%, PR: 0.46; 95% CI: 0.29, 0.73). In both trials, the 2 N groups also had significantly lower prevalences of iron deficiency, iron deficiency anemia, and low vitamin B-12 and, in Kenya, a lower prevalence of folate and vitamin A deficiencies. In Bangladesh, the WSH group had a lower prevalence of anemia (12.8%; PR: 0.74; 95% CI: 0.54, 1.00) than the control group, whereas in Kenya, the WSH+N group had a lower prevalence of anemia than did the N group (PR: 0.75; 95% CI: 0.53, 1.07), but this was not significant (P = 0.102).

Conclusions

IYCF counseling with LNSs reduced the risks of anemia, iron deficiency, and low vitamin B-12. Effects on folate and vitamin A varied between studies. Improvements in WSH also reduced the risk of anemia in Bangladesh but did not provide added benefit over the nutrition-specific intervention. These trials were registered at clinicaltrials.gov as NCT01590095 (Bangladesh) and NCT01704105 (Kenya).

Prevalence and risk factors of preconception anemia: A community based cross sectional study of rural women of reproductive age in northeastern Tanzania

BACKGROUND

Anemia is a major public health problem that adversely affects pregnancy outcomes. The prevalence of anemia among pregnant women before conception is not well known in Tanzania. The aim of this study was to determine the prevalence, types, and risk factors of preconception anemia in women of reproductive age from a rural Tanzanian setting.

METHODS

Trained field workers visited households to identify all female residents aged 18-40 years and invited them to the nearby health facility for screening and enrolment into this study. Baseline samples were collected to measure hemoglobin levels, serum ferritin, vitamin B12, folate, C-reactive protein, alanine amino-transferase, the presence of malaria, HIV, and soil transmitted helminth infections. Anthropometric and socio-economic data were recorded alongside with clinical information of participants. Logistic regression analysis was used to determine the adjusted odds ratios (AOR) for the factors associated with preconception anemia.

FINDINGS

Of 1248 women enrolled before conception, 36.7% (95% confidence interval (CI) 34.1-39.4) had anemia (hemoglobin <12 g/dL) and 37.6% (95% CI 34.9-40.4) had iron deficiency. For more than half of the anemic cases, iron deficiency was also diagnosed (58.8%, 95% CI 54.2-63.3). Anemia was independently associated with increased age (AOR 1.05, 95% CI 1.03-1.07), malaria infection at enrolment (AOR 2.21, 95% CI 1.37-3.58), inflammation (AOR 1.77, 95% CI 1.21-2.60) and iron deficiency (AOR 4.68, 95% CI 3.55-6.17). The odds of anemia were reduced among women with increased mid-upper arm circumference (AOR 0.90, 95% CI 0.84-0.96).

CONCLUSION

Anemia among women of reproductive age before conception was prevalent in this rural setting. Increased age, iron deficiency, malaria infection and inflammation were significant risk factors associated with preconception anemia, whereas increased mid-upper arm circumference was protective against anemia. Interventions to ensure adequate iron levels as well as malaria control before conception are needed to prevent anemia before and during pregnancy and improve birth outcomes in this setting.

TRIAL REGISTRATION

NCT02191683.

Malaria causes long-term effects on markers of iron status in children: a critical assessment of existing clinical and epidemiological tools

Background

Most epidemiological studies on the interplay between iron deficiency and malaria risk classify individuals as iron-deficient or iron-replete based on inflammation-dependent iron markers and adjustment for inflammation by using C-reactive protein (CRP) or α-1-acid glycoprotein (AGP). The validity of this approach and the usefulness of fibroblast growth factor 23 (FGF23) as a proposed inflammation-independent iron marker were tested.

Methods

Conventional iron markers and FGF23 were measured in children with acute falciparum malaria and after 1, 2, 4, and 6 weeks. Children, who were transfused or received iron supplementation in the follow-up period, were excluded, and iron stores were considered to be stable throughout. Ferritin levels 6 weeks after admission were used as a reference for admission iron status and compared with iron markers at different time points.

Results

There were long-term perturbations in iron markers during convalescence from acute malaria. None of the tested iron parameters, including FGF23, were independent of inflammation. CRP and AGP normalized faster than ferritin after malaria episodes.

Conclusion

Malaria may bias epidemiological studies based on inflammation-dependent iron markers. Better markers of iron status during and after inflammation are needed in order to test strategies for iron supplementation in populations at risk of malaria.

Sickle Cell and α+-Thalassemia Traits Influence the Association between Ferritin and Hepcidin in Rural Kenyan Children Aged 14-26 Months

Background

The relation between subclinical hemoglobinopathies and concentrations of the iron-regulatory hormone hepcidin is not well characterized.

Objective

We investigated the relation of hepcidin concentration with hemoglobinopathies among young children in Kenya.

Methods

We quantified serum hepcidin and ferritin in 435 Kenyan children aged 14-20 mo in a subsample of the Water, Sanitation, and Handwashing (WASH) Benefits Trial. Blood samples were genotyped for α+-thalassemia and for sickle cell disorder. Hepcidin was compared across sickle cell and α+-thalassemia genotypes separately by using generalized linear models, and children who were normozygous for both conditions were also compared with those who had either of these conditions. In the association between hepcidin and ferritin, we assessed effect modification by genotype.

Results

In this population, we found that 16.2% had sickle cell trait and 0.2% had sickle cell disorder, whereas 40.0% were heterozygous for α+-thalassemia and 8.2% were homozygous. Hepcidin concentration did not differ by genotype, but effect modification was found by genotype in the association between hepcidin and ferritin (P < 0.1). Among normozygous sickle cell children (HbAA), there was an association between hepcidin and ferritin (β = 0.92; 95% CI: 0.72, 1.10). However, among those with sickle cell trait (HbAS), the association was no longer significant (β = 0.31; 95% CI: -0.04, 0.66). Similarly, among children who were normozygous (αα/αα) or heterozygous (-α/αα) for α+-thalassemia, hepcidin and ferritin were significantly associated [β = 0.94 (95% CI: 0.68, 1.20) and β = 0.77 (95% CI: 0.51, 1.03), respectively]; however, in children who were homozygous for α+-thalassemia (-α/-α), there was no longer a significant association (β = 0.45; 95% CI: -0.10, 1.00).

Conclusion

Hepcidin was not associated with hemoglobin genotype, but there may be a difference in the way hepcidin responds to iron status among those with either sickle cell trait or homozygous α+-thalassemia in young Kenyan children. This trial was registered at clinicaltrials.gov as NCT01704105.

Effectiveness of a Program Intervention with Reduced-Iron Multiple Micronutrient Powders on Iron Status, Morbidity and Growth in Young Children in Ethiopia

Despite the potential for improving iron status and child growth in low- and middle-income settings, concerns on the safety of high iron dosages of Micronutrient Powders (MNP currently limit their applicability in programs. We examined the effectiveness and risks of an integrated complementary feeding program with low iron dose (6 mg/serving) MNP among 6–23-month-old Ethiopian children using a quasi-experimental study design comparing children from five intervention districts (n = 1172) to those from four matched non-intervention districts (n = 1137). Haemoglobin concentrations increased in intervention and decreased in non-intervention children (group-difference +3.17 g/L), but without improvement in iron stores. Intervention children were 2.31 times more likely to have diarrhoea and 2.08 times more likely to have common cold and flu, but these differences decreased towards the end of the intervention. At end line, intervention children had higher mean Height-for-Age Zscore (HAZ) and a 51% reduced odds of being stunted compared to non-intervention children. MNP with low iron dose, when provided combined with other Infant and Young Child Feeding (IYCF) interventions, marginally improved haemoglobin status and resulted in a remarkable improvement in linear growth in 6–23-month-old children. These benefits likely outweigh the relatively small increase in the risk of diarrhoea.

The role of the Patient-Generated Subjective Global Assessment (PG-SGA) and biochemical markers in predicting anemia patients with cancer

PURPOSE

The causes of anemia and the common side effects of cancer are multifactorial. Malnutrition is one of the alleged components of the aforementioned complications. This study planned to investigate the relationship among biochemical markers, Patient-Generated Subjective Global Assessment (PG-SGA), and anemia in cancer patients.

METHODS

This analysis consisted of 234 patients who were enlisted in the Department of Oncology of the First Hospital of Shanxi Medical University between December 2016 and October 2017. The groups were divided into anemic and non-anemic patients. The gathered data primarily discussed the patients' basic information, specifically the age, gender, smoking, alcohol consumption, and nutritional status based on levels of serum biochemical markers and PG-SGA scores.

RESULTS

Among the participants, 31.2% of the cancer patients were diagnosed with anemia whereas, according to the scores of PG.SGA, 65.0% of patients experienced malnourishment. The anemia was significantly associated with biochemical markers, expecting a transferrin in univariable analyses. Binary logistic regression analysis between anemic cancer patients and non-anemic cancer patients suggested that high PG-SGA score (odds ratio 1.082; 95% CI 1.027-1.141) implied the risk factor for anemia, and high PG-SGA scores could potentially increase the risk of anemia. The multiple regression analysis showed that hemoglobin concentration (OR 0.575; 95% CI 0.450-0.736) and PG-SGA score (OR 1.231; 95% CI 1.013-1.496) were linked to anemia. However, total protein, albumin, prealbumin, serum iron, transferrin, and transferrin saturation lacked a strong relationship with anemia.

CONCLUSION

Anemia prevailed in cancer patients, as nutritionally assessed by PG-SGA, while hemoglobin established a linkage with anemia as they could provide extra predictive information about anemia in patients diagnosed with cancer.

Limitations of Serum Ferritin in Diagnosing Iron Deficiency in Inflammatory Conditions

Patients with inflammatory conditions such as inflammatory bowel disease (IBD), chronic heart failure (CHF), and chronic kidney disease (CKD) have high rates of iron deficiency with adverse clinical consequences. Under normal circumstances, serum ferritin levels are a sensitive marker for iron status but ferritin is an acute-phase reactant that becomes elevated in response to inflammation, complicating the diagnosis. Proinflammatory cytokines also trigger an increase in hepcidin, which restricts uptake of dietary iron and promotes sequestration of iron by ferritin within storage sites. Patients with inflammatory conditions may thus have restricted availability of iron for erythropoiesis and other cell functions due to increased hepcidin expression, despite normal or high levels of serum ferritin. The standard threshold for iron deficiency (<30 μg/L) therefore does not apply and transferrin saturation (TSAT), a marker of iron availability, should also be assessed. A serum ferritin threshold of <100 μg/L or TSAT < 20% can be considered diagnostic for iron deficiency in CHF, CKD, and IBD. If serum ferritin is 100-300 μg/L, TSAT < 20% is required to confirm iron deficiency. Routine surveillance of serum ferritin and TSAT in these at-risk groups is advisable so that iron deficiency can be detected and managed.

Malaria and Iron Load at the First Antenatal Visit in the Rural South Kivu, Democratic Republic of the Congo: Is Iron Supplementation Safe or Could It Be Harmful?

We investigated the relationship between malaria infection and iron status in 531 pregnant women in South Kivu, Democratic Republic of the Congo. Sociodemographic data, information on morbidity, and clinical data were collected. A blood sample was collected at the first antenatal visit to diagnose malaria and measure serum ferritin (SF), soluble transferrin receptor, C-reactive protein, and α1-acid-glycoprotein. Malaria prevalence was 7.5%. Median (interquartile range) SF (adjusted for inflammation) was significantly higher in malaria-infected (82.9 μg/L [56.3-130.4]) than in non-infected (39.8 μg/L [23.6-60.8]) women (P < 0.001). Similarly, estimated mean body iron store was higher in malaria-infected women (P < 0.001). Malaria was significantly and independently associated with high levels of SF. Efforts to improve malaria prevention while correcting iron deficiency and anemia during pregnancy are warranted.

Iron Supplementation during Pregnancy and Infancy: Uncertainties and Implications for Research and Policy

Iron is particularly important in pregnancy and infancy to meet the high demands for hematopoiesis, growth and development. Much attention has been given to conditions of iron deficiency (ID) and iron deficient anemia (IDA) because of the high global prevalence estimated in these vulnerable life stages. Emerging and preliminary evidence demonstrates, however, a U-shaped risk at both low and high iron status for birth and infant adverse health outcomes including growth, preterm birth, gestational diabetes, gastrointestinal health, and neurodegenerative diseases during aging. Such evidence raises questions about the effects of high iron intakes through supplementation or food fortification during pregnancy and infancy in iron-replete individuals. This review examines the emerging as well as the current understanding of iron needs and homeostasis during pregnancy and infancy, uncertainties in ascertaining iron status in these populations, and issues surrounding U-shaped risk curves in iron-replete pregnant women and infants. Implications for research and policy are discussed relative to screening and supplementation in these vulnerable populations, especially in developed countries in which the majority of these populations are likely iron-replete.

Assessment of iron status in settings of inflammation: challenges and potential approaches

The determination of iron status is challenging when concomitant infection and inflammation are present because of confounding effects of the acute-phase response on the interpretation of most iron indicators. This review summarizes the effects of inflammation on indicators of iron status and assesses the impact of a regression analysis to adjust for inflammation on estimates of iron deficiency (ID) in low- and high-infection-burden settings. We overviewed cross-sectional data from 16 surveys for preschool children (PSC) (n = 29,765) and from 10 surveys for nonpregnant women of reproductive age (WRA) (n = 25,731) from the Biomarkers Reflecting the Inflammation and Nutritional Determinants of Anemia (BRINDA) project. Effects of C-reactive protein (CRP) and α1-acid glycoprotein (AGP) concentrations on estimates of ID according to serum ferritin (SF) (used generically to include plasma ferritin), soluble transferrin receptor (sTfR), and total body iron (TBI) were summarized in relation to infection burden (in the United States compared with other countries) and population group (PSC compared with WRA). Effects of the concentrations of CRP and AGP on SF, sTfR, and TBI were generally linear, especially in PSC. Overall, regression correction changed the estimated prevalence of ID in PSC by a median of +25 percentage points (pps) when SF concentrations were used, by -15 pps when sTfR concentrations were used, and by +14 pps when TBI was used; the estimated prevalence of ID in WRA changed by a median of +8 pps when SF concentrations were used, by -10 pps when sTfR concentrations were used, and by +3 pps when TBI was used. In the United States, inflammation correction was done only for CRP concentrations because AGP concentrations were not measured; regression correction for CRP concentrations increased the estimated prevalence of ID when SF concentrations were used by 3 pps in PSC and by 7 pps in WRA. The correction of iron-status indicators for inflammation with the use of regression correction appears to substantially change estimates of ID prevalence in low- and high-infection-burden countries. More research is needed to determine the validity of inflammation-corrected estimates, their dependence on the etiology of inflammation, and their applicability to individual iron-status assessment in clinical settings.

Iron status of toddlers, nonpregnant females, and pregnant females in the United States

Background: Total-body iron stores (TBI), which are calculated from serum ferritin and soluble transferrin receptor concentrations, can be used to assess the iron status of populations in the United States.Objective: This analysis, developed to support workshop discussions, describes the distribution of TBI and the prevalence of iron deficiency (ID) and ID anemia (IDA) among toddlers, nonpregnant females, and pregnant females.Design: We analyzed data from NHANES; toddlers aged 12-23 mo (NHANES 2003-2010), nonpregnant females aged 15-49 y (NHANES 2007-2010), and pregnant females aged 12-49 y (NHANES 1999-2010). We used SAS survey procedures to plot distributions of TBI and produce prevalence estimates of ID and IDA for each target population. All analyses were weighted to account for the complex survey design.Results: According to these data, ID prevalences (± SEs) were 15.1% ± 1.7%, 10.4% ± 0.5%, and 16.3% ± 1.3% in toddlers, nonpregnant females, and pregnant females, respectively. ID prevalence in pregnant females increased significantly with each trimester (5.3% ± 1.5%, 12.7% ± 2.3%, and 27.5% ± 3.5% in the first, second, and third trimesters, respectively). Racial disparities in the prevalence of ID among both nonpregnant and pregnant females exist, with Mexican American and non-Hispanic black females at greater risk of ID than non-Hispanic white females. IDA prevalence was 5.0% ± 0.4% and 2.6% ± 0.7% in nonpregnant and pregnant females, respectively.Conclusions: Available nationally representative data suggest that ID and IDA remain a concern in the United States. Estimates of iron-replete status cannot be made at this time in the absence of established cutoffs for iron repletion based on TBI. The study was registered at clinicaltrials.gov as NCT03274726.

Effects of long-term weekly iron and folic acid supplementation on lower genital tract infection - a double blind, randomised controlled trial in Burkina Faso

BACKGROUND

Provision of routine iron supplements to prevent anaemia could increase the risk for lower genital tract infections as virulence of some pathogens depends on iron availability. This trial in Burkina Faso assessed whether weekly periconceptional iron supplementation increased the risk of lower genital tract infection in young non-pregnant and pregnant women.

METHODS

Genital tract infections were assessed within a double blind, controlled, non-inferiority trial of malaria risk among nulliparous women, randomised to receive either iron and folic acid or folic acid alone, weekly, under direct observation for 18 months. Women conceiving during this period entered the pregnancy cohort. End assessment (FIN) for women remaining non-pregnant was at 18 months. For the pregnancy cohort, end assessment was at the first scheduled antenatal visit (ANC1). Infection markers included Nugent scores for abnormal flora and bacterial vaginosis (BV), T. vaginalis PCR, vaginal microbiota, reported signs and symptoms, and antibiotic and anti-fungal prescriptions. Iron biomarkers were assessed at baseline, FIN and ANC1. Analysis compared outcomes by intention to treat and in iron replete/deficient categories.

RESULTS

A total of 1954 women (mean 16.8 years) were followed and 478 (24.5%) became pregnant. Median supplement adherence was 79% (IQR 59-90%). Baseline BV prevalence was 12.3%. At FIN and ANC1 prevalence was 12.8% and 7.0%, respectively (P < 0.011). T. vaginalis prevalence was 4.9% at FIN and 12.9% at ANC1 (P < 0.001). BV and T. vaginalis prevalence and microbiota profiles did not differ at trial end-points. Iron-supplemented non-pregnant women received more antibiotic treatments for non-genital infections (P = 0.014; mainly gastrointestinal infections (P = 0.005), anti-fungal treatments for genital infections (P = 0.014) and analgesics (P = 0.008). Weekly iron did not significantly reduce iron deficiency prevalence. At baseline, iron-deficient women were more likely to have normal vaginal flora (P = 0.016).

CONCLUSIONS

Periconceptional weekly iron supplementation of young women did not increase the risk of lower genital tract infections but did increase general morbidity in the non-pregnant cohort. Unabsorbed gut iron due to malaria could induce enteric infections, accounting for the increased administration of antibiotics and antifungals in the iron-supplemented arm. This finding reinforces concerns about routine iron supplementation in highly malarious areas.

TRIAL REGISTRATION

Trial registration number NCT01210040 . Registered with Clinicaltrials.gov on 27 September 2010.

Simultaneous assessment of iodine, iron, vitamin A, malarial antigenemia, and inflammation status biomarkers via a multiplex immunoassay method on a population of pregnant women from Niger

Deficiencies of vitamin A, iron, and iodine are major public health concerns in many low- and middle-income countries, but information on their status in populations is often lacking due to high costs and logistical challenges associated with assessing micronutrient status. Accurate, user-friendly, and low-cost analytical tools are needed to allow large-scale population surveys on micronutrient status. We present the expansion of a 7-plex protein microarray tool for the simultaneous measurement of up to seven biomarkers with relevance to the assessment of the key micronutrients iron, iodine, and vitamin A, and inflammation and malaria biomarkers: α-1-acid glycoprotein, C-reactive protein, ferritin, retinol binding protein 4, soluble transferrin receptor, thyroglobulin, and histidine-rich protein II. Assay performance was assessed using international reference standards and then verified by comparing the multiplexed and conventional immunoassay results on a training panel of plasma samples collected from US adults. These data were used to assign nominal concentrations to the calibrators of the assay to further improve performance which was then assessed by interrogating plasma samples from a cohort of pregnant women from Niger. The correlation between assays for each biomarker measured from this cohort was typically good, with the exception of thyroglobulin, and the sensitivity ranged from 74% to 93%, and specificity from 81% to 98%. The 7-Plex micronutrient assay has the potential for use as an affordable tool for population surveillance of vitamin A, iron, and iodine deficiencies as well as falciparum malarial parasitemia infectivity and inflammation. The assay is easy-to-use, requires minimal sample volume, and is scalable, rapid, and accurate—needing only a low-cost reader and basic equipment present in most reference laboratory settings and so may be employed by low and middle income countries for micronutrient surveillance to inform on status in key populations. Micronutrient deficiencies including iron, iodine, and vitamin A affect a significant portion of the world’s population. Efforts to assess the prevalence of these deficiencies in vulnerable populations are challenging, partly due to measurement tools that are inadequate for assessing multiple micronutrients in large-scale population surveys. We have developed a 7-plex immunoassay for the simultaneous measurement of seven biomarkers relevant to assessing iodine, iron, and vitamin A status, inflammation and Plasmodium falciparum parasitemia by measuring levels of thyroglobulin, ferritin, soluble transferrin receptor, retinol binding protein 4, α-1-acid glycoprotein, C-reactive protein, and histidine-rich protein II. This 7-plex immunoassay technique has potential as a rapid and effective tool for use in large-scale surveys and assessments of nutrition intervention programs in low- and middle-income countries.

Iron deficiency was not the major cause of anemia in rural women of reproductive age in Sidama zone, southern Ethiopia: A cross-sectional study

Background

Anemia, which has many etiologies, is a moderate/severe public health problem in young children and women of reproductive age in many developing countries. The aim of this study was to investigate prevalence of iron deficiency, anemia, and iron deficiency anemia using multiple biomarkers and to evaluate their association with food insecurity and food consumption patterns in non-pregnant women from a rural area of southern Ethiopia.

Methods

A cross-sectional study was conducted in 202 rural women of reproductive age in southern Ethiopia. Anthropometrics and socio-demographic data were collected. A venipuncture blood sample was analyzed for hemoglobin (Hb) and for biomarkers of iron status. Biomarkers were skewed and were log transformed before analysis. Mean, median, Pearson’s correlations and ordinary least-squares regressions were calculated.

Results

Median (IQR) Hb was 138 (127, 151) g/L. Based on an altitude-adjusted (1708 m) cutoff of 125 g/L for Hb, 21.3% were anemic. Plasma ferritin was <15 μg/L in 18.6% of the women. Only one woman had α-1-acid glycoprotein (AGP) >1.0 g/L; four women (2%) had > 5 mg/L of C-reactive protein (CRP). Of the 43 women who were anemic, 23.3% (10 women) had depleted iron stores based on plasma ferritin. Three of these had elevated soluble transferrin receptors (sTfR). Hemoglobin (Hb) concentration was negatively correlated with sTfR (r = -0.24, p = 0.001), and positively correlated with ferritin (r = 0.17, p = 0.018), plasma iron (r = 0.15, p = 0.046), transferrin saturation (TfS) (r = 0.15, p = 0.04) and body iron (r = 0.14, p = 0.05). Overall prevalence of iron deficiency anemia was only 5%.

Conclusion

Iron deficiency anemia was not prevalent in the study population, despite the fact that anemia would be classified as a moderate public health problem.

Methodologic approach for the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project

Background: The Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project is a multiagency and multicountry collaboration that was formed to improve micronutrient assessment and to better characterize anemia.Objectives: The aims of the project were to 1) identify factors associated with inflammation, 2) assess the relations between inflammation, malaria infection, and biomarkers of iron and vitamin A status and compare adjustment approaches, and 3) assess risk factors for anemia in preschool children (PSC) and women of reproductive age (WRA).Design: The BRINDA database inclusion criteria included surveys that 1) were conducted after 2004, 2) had target groups of PSC, WRA, or both, and 3) used a similar laboratory methodology for the measurement of ≥1 biomarker of iron [ferritin or soluble transferrin receptor or vitamin A status (retinol-binding protein or retinol)] and ≥1 biomarker of inflammation (α-1-acid glycoprotein or C-reactive protein). Individual data sets were standardized and merged into a BRINDA database comprising 16 nationally and regionally representative surveys from 14 countries. Collectively, the database covered all 6 WHO geographic regions and contained ∼30,000 PSC and 27,000 WRA. Data were analyzed individually and combined with the use of a meta-analysis.Results: The methods that were used to standardize the BRINDA database and the analytic approaches used to address the project's research questions are presented in this article. Three approaches to adjust micronutrient biomarker concentrations in the presence of inflammation and malaria infection are presented, along with an anemia conceptual framework that guided the BRINDA project's anemia analyses.Conclusions: The BRINDA project refines approaches to interpret iron and vitamin A biomarker values in settings of inflammation and malaria infection and suggests the use of a new regression approach as well as proposes an anemia framework to which real-world data can be applied. Findings can inform guidelines and strategies to prevent and control micronutrient deficiencies and anemia globally.

Adjusting total body iron for inflammation: Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project

Background: Total body iron (TBI) that is calculated from ferritin and soluble transferrin receptor (sTfR) allows for the evaluation of the full range of iron status from deficiency to excess. However, both ferritin and sTfR are affected by inflammation and malaria, which may require a statistical adjustment. TBI has been used to assess iron status in the United States, but its use worldwide and in settings with inflammation has been limited.Objective: We examine whether inflammation-adjusted ferritin and sTfR concentrations affect TBI values and the prevalence of low TBI (<0 mg/kg) in preschool children (PSC) (age range: 6-59 mo) and women of reproductive age (WRA) (age range: 15-49 y).Design: Cross-sectional data for PSC (8 surveys; n = 8413) and WRA (4 surveys; n = 4258) from the Biomarkers Reflecting the Inflammation and Nutritional Determinants of Anemia (BRINDA) project were analyzed individually and combined. TBI and the prevalence of low TBI were compared following 3 adjustment approaches for ferritin and sTfR: 1) the exclusion of individuals with inflammation (C-reactive protein concentration >5 mg/L or α-1-acid glycoprotein concentration >1 g/L), 2) the application of arithmetic correction factors, and 3) the use of regression correction.Results: Regardless of the method that was used to adjust ferritin and sTfR for inflammation, the adjusted mean TBI decreased in both PSC and WRA compared with unadjusted values. Subsequently, inflammation-adjusted TBI increased the prevalence of low TBI by a median of 4-14 percentage points (pps) in PSC and 1-3 pps in WRA compared with unadjusted TBI. The regression approach resulted in a greater median increase than was achieved with the exclusion or correction-factor approaches, and accounting for malaria in addition to inflammation did not have an added effect on the prevalence estimates.Conclusion: The prevalence of low TBI is underestimated if it is not adjusted by inflammation, particularly in children living in areas with a high prevalence of inflammation.

Predictors of anemia in preschool children: Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project

Background: A lack of information on the etiology of anemia has hampered the design and monitoring of anemia-control efforts.Objective: We aimed to evaluate predictors of anemia in preschool children (PSC) (age range: 6-59 mo) by country and infection-burden category.Design: Cross-sectional data from 16 surveys (n = 29,293) from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project were analyzed separately and pooled by category of infection burden. We assessed relations between anemia (hemoglobin concentration <110 g/L) and severe anemia (hemoglobin concentration <70 g/L) and individual-level (age, anthropometric measures, micronutrient deficiencies, malaria, and inflammation) and household-level predictors; we also examined the proportion of anemia with concomitant iron deficiency (defined as an inflammation-adjusted ferritin concentration <12 μg/L). Countries were grouped into 4 categories on the basis of risk and burden of infectious disease, and a pooled multivariable logistic regression analysis was conducted for each group.Results: Iron deficiency, malaria, breastfeeding, stunting, underweight, inflammation, low socioeconomic status, and poor sanitation were each associated with anemia in >50% of surveys. Associations between breastfeeding and anemia were attenuated by controlling for child age, which was negatively associated with anemia. The most consistent predictors of severe anemia were malaria, poor sanitation, and underweight. In multivariable pooled models, child age, iron deficiency, and stunting independently predicted anemia and severe anemia. Inflammation was generally associated with anemia in the high- and very high-infection groups but not in the low- and medium-infection groups. In PSC with anemia, 50%, 30%, 55%, and 58% of children had concomitant iron deficiency in low-, medium-, high-, and very high-infection categories, respectively.Conclusions: Although causal inference is limited by cross-sectional survey data, results suggest anemia-control programs should address both iron deficiency and infections. The relative importance of factors that are associated with anemia varies by setting, and thus, country-specific data are needed to guide programs.

Research, policy, and programmatic considerations from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project

The Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project sought to inform the interpretation of iron and vitamin A biomarkers (ferritin, serum transferrin receptor, and retinol binding protein) in settings of prevalent inflammation as well as the prevention of and control strategies to address anemia. Our purpose is to comment on the contributions of the BRINDA to advance global knowledge with regard to iron and vitamin A status assessment in women and preschool children and to analyze the findings in terms of their rigor and usefulness for global nutrition research and programs. BRINDA investigators found that the acute-phase response is so prevalent that it must be assessed in surveys of iron and vitamin A status for valid interpretation of micronutrient biomarkers. Furthermore, they found that C-reactive protein and α-1-acid glycoprotein provide important and different information about these responses and that common survey variables cannot replace the information they provide. Developing a method for adjusting micronutrient biomarkers for the independent influence of inflammation is challenging and complex, and BRINDA has brought greater clarity to this challenge through the use of large and diverse data sets. When comparing approaches, the regression methods appear to perform best when sample sizes are sufficient and adequate statistical capacity is available. Further correction for malaria does not appear to materially alter regression-adjusted prevalence estimates. We suggest that researchers present both adjusted and unadjusted values for the micronutrient biomarkers. BRINDA findings confirm that iron deficiency is a common and consistent risk factor for anemia globally and that anemia control must combine iron interventions with control of infection and inflammation. Anemia control strategies must be informed by local data. By applying the knowledge in these studies, researchers, program planners, and evaluators working in populations with prevalent inflammation can use and interpret biomarkers with more confidence, tempered with necessary caution.

Predictors of anemia in women of reproductive age: Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project

Background: Anemia in women of reproductive age (WRA) (age range: 15-49 y) remains a public health problem globally, and reducing anemia in women by 50% by 2025 is a goal of the World Health Assembly.Objective: We assessed the associations between anemia and multiple proximal risk factors (e.g., iron and vitamin A deficiencies, inflammation, malaria, and body mass index) and distal risk factors (e.g., education status, household sanitation and hygiene, and urban or rural residence) in nonpregnant WRA.Design: Cross-sectional, nationally representative data from 10 surveys (n = 27,018) from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project were analyzed individually and pooled by the infection burden and risk in the country. We examined the severity of anemia and measured the bivariate associations between anemia and factors at the country level and by infection burden, which we classified with the use of the national prevalences of malaria, HIV, schistosomiasis, sanitation, and water-quality indicators. Pooled multivariate logistic regression models were constructed for each infection-burden category to identify independent determinants of anemia (hemoglobin concertation <120 g/L).Results: Anemia prevalence was ∼40% in countries with a high infection burden and 12% and 7% in countries with moderate and low infection burdens, respectively. Iron deficiency was consistently associated with anemia in multivariate models, but the proportion of anemic women who were iron deficient was considerably lower in the high-infection group (35%) than in the moderate- and low-infection groups (65% and 71%, respectively). In the multivariate analysis, inflammation, vitamin A insufficiency, socioeconomic status, and age were also significantly associated with anemia, but malaria and vitamin B-12 and folate deficiencies were not.Conclusions: The contribution of iron deficiency to anemia varies according to a country's infection burden. Anemia-reduction programs for WRA can be improved by considering the underlying infection burden of the population and by assessing the overlap of micronutrient deficiencies and anemia.