Hemoglobin correction factors for estimating the prevalence of iron deficiency anemia in pregnant women residing at high altitudes in Bolivia

Overview of Trends in Anemia and Iron Deficiency in the Mexican Population From 1999 to 2018-19

BACKGROUND

Despite the emergence of diverse programs in Mexico to address anemia and micronutrient deficiencies in disadvantaged groups, progress on reducing their prevalence has stagnated. In Mexico, anemia surveillance at the population level is conducted through the National Health and Nutrition Survey ENSANUT (for its acronym in Spanish).

OBJECTIVE

To overview the trends in anemia and iron deficiency (ID) from 1999 to 2018-19 in the Mexican population before COVID-19 pandemic.

METHODS

Data from five nationwide surveys in Mexico were used. Where available, data on anemia, ID, and ID anemia (IDA) were extracted from ENSANUTs 1999, 2006, 2012, 2016, and 2018-19 in participants from 1 to 99 years old. Blood sample collection methods were similar across surveys (1999-2018) where capillary drop blood was used to estimate Hb using a HemoCue and serum blood samples to measure ferritin and C-reactive protein concentration.

RESULTS

The trend in anemia prevalence shows a U-shape from 1999 to 2018-19 in <60 years old. In older adults (≥60 years), an increasing trend was observed. Anemia declined progressively from 1999 to 2012 but increased from 2016 to 2018-19 in comparison with 2012. In contrast, ID declined from 2006 to 2018-19, mainly in children, while IDA did not change over this period. In older adults, ID prevalence remained constant over time.

CONCLUSIONS

The shifting trend in anemia prevalence across ENSANUTs 1999 through 2018-19 did not mimic the decreasing trend of ID over the same period of time. Other noncausal factors seem to play an important role in the variability of hemoglobin measurements.

Prevalence and factors associated with the coexistence of overweight/obesity and anaemia among women of reproductive age in Guinea

OBJECTIVE

To determine the prevalence and associated factors of the coexistence of overweight or obesity (OWOB) and anaemia among non-pregnant Guinean women aged 15-49 years.

DESIGN

The analysis was performed using data from the 2018 Guinean Demographic and Health Survey. Multivariate logistic regression was used to identify factors associated with the coexistence of OWOB and anaemia (OWOB + anaemia) among non-pregnant Guinean women.

SETTING

Guinea.

PARTICIPANTS

A total of 4783 non-pregnant women aged 15-49 years with valid data on the nutritional status (BMI and Hb level) were included in the analysis.

RESULTS

The prevalence of coexistence of OWOB and anaemia among non-pregnant women was 11·16 % (95% CI: 10·05, 12·37). The following variables were associated with OWOB + anaemia in multivariate models (adjusted OR (AOR) 95% CI): higher wealth index (AOR = 4·69; 95% CI: 2·62, 8·39), middle wealth index (AOR = 1·96; 95% CI: 1·31, 2·93), four or more antenatal visits (AOR = 1·62; CI: 1·16, 2·28), having four or more children (AOR = 2·47; 95% CI: 1·37, 4·43) and the rural areas (AOR = 0·59; 95% CI: 0·37, 0·95).

CONCLUSION

The current study's findings reveal that OWOB + anaemia concerned one-tenth of non-pregnant women. Associated factors were household wealth index, multiparity, antenatal visits and rural areas. Thus, there is a need to design specific interventions to prevent the double burden of malnutrition among women of reproductive age. Interventions should include promoting physical exercise, family planning, healthy eating and raising awareness of behavioural change.

Prediction of plasma volume and total hemoglobin mass with machine learning

Hemoglobin concentration ([Hb]) is used for the clinical diagnosis of anemia, and in sports as a marker of blood doping. [Hb] is however subject to significant variations mainly due to shifts in plasma volume (PV). This study proposes a newly developed model able to accurately predict total hemoglobin mass (Hbmass) and PV from a single complete blood count (CBC) and anthropometric variables in healthy subject. Seven hundred and sixty-nine CBC coupled to measures of Hbmass and PV using a CO-rebreathing method were used with a machine learning tool to calculate an estimation model. The predictive model resulted in a root mean square error of 33.2 g and 35.6 g for Hbmass, and 179 mL and 244 mL for PV, in women and men, respectively. Measured and predicted data were significantly correlated (p < 0.001) with a coefficient of determination (R2 ) ranging from 0.76 to 0.90 for Hbmass and PV, in both women and men. The Bland-Altman bias was on average 0.23 for Hbmass and 4.15 for PV. We herewith present a model with a robust prediction potential for Hbmass and PV. Such model would be relevant in providing complementary data in contexts such as the epidemiology of anemia or the individual monitoring of [Hb] in anti-doping.

Epstein-Barr Virus Infection Is Associated with Elevated Hepcidin Levels

EBV and Helicobacter pylori (H. pylori) cause highly prevalent persistent infections as early as in childhood. Both pathogens are associated with gastric carcinogenesis. H. pylori interferes with iron metabolism, enhancing the synthesis of acute-phase proteins hepcidin, C-reactive protein (CRP), and α-1 glycoprotein (AGP), but we do not know whether EBV does the same. In this study, we correlated the EBV antibody levels and the serum levels of hepcidin, CRP, and AGP in 145 children from boarding schools in Mexico City. We found that children IgG positive to EBV antigens (VCA, EBNA1, and EA) presented hepcidin, AGP, and CRP levels higher than uninfected children. Hepcidin and AGP remained high in children solely infected with EBV, while CRP was only significantly high in coinfected children. We observed positive correlations between hepcidin and EBV IgG antibodies (p < 0.5). Using the TCGA gastric cancer database, we also observed an association between EBV and hepcidin upregulation. The TCGA database also allowed us to analyze the two important pathways controlling hepcidin expression, BMP−SMAD and IL-1β/IL-6. We observed only the IL-1β/IL-6-dependent inflammatory pathway being significantly associated with EBV infection. We showed here for the first time an association between EBV and enhanced levels of hepcidin. Further studies should consider EBV when evaluating iron metabolism and anemia, and whether in the long run this is an important mechanism of undernourishment and EBV gastric carcinogenesis.

Consumption of Micronutrient Powder, Syrup or Fortified Food Significantly Improves Zinc and Iron Status in Young Mexican Children: A Cluster Randomized Trial

The objective of this study was to compare the effect of three micronutrient products on biomarkers of iron and zinc status of Mexican children 6−12 months of age. As part of research to improve the impact of a national program, 54 communities were randomly assigned to receive: (1) fortified food (FF), provided by the program at the time, or (2) micronutrient powders (MNP) or (3) syrup. Each product contained 10 mg each of zinc and iron, plus other micronutrients. Children consumed the product 6 days/week for four months. Primary outcomes were changes in serum zinc, ferritin, soluble transferrin receptor, hemoglobin concentrations, and their deficiencies. Zinc concentration increased significantly from baseline to follow-up in all groups, with the largest change in the syrup group (geometric mean difference: +4.4 µmol/L; 95%CI: 3.2, 5.5), followed by MNP (+2.9 µmol/L; 95%CI: 2.1, 3.6) and FF (+0.9 µmol/L; 95%CI: 0.3, 1.6). There was a significant increase in hemoglobin concentration (+5.5 g/L; 2.5, 8.4) and a significant reduction in anemia prevalence (44.2% to 26.8%, p < 0.01) only in the MNP group. Compliance differed significantly among groups (MNP vs. FF, p = 0.04; MNP vs. syrup, p = 0.04), but may not fully explain the greater improvement in zinc and iron status in the syrup and MNP groups. The food matrix may influence nutrient utilization from supplements.

Malnutrition in all its forms by wealth, education and ethnicity in Latin America: who are more affected?

OBJECTIVE

To summarise the findings from this supplemental issue on the distribution of malnutrition (stunting/short stature, anaemia and overweight) by wealth, education and ethnicity within and between ten Latin American countries.

DESIGN

We retrieved information from each country's article and estimated the average difference in the prevalence of malnutrition between groups. We estimated the associations between countries' malnutrition prevalence and GDP, percentage of women with high education and percentage of non-indigenous ethnicity.

SETTING

Nationally representative surveys from ten Latin American countries conducted between 2005 and 2017.

PARTICIPANTS

Children (<5 years), adolescent women (11-19 years) and adult women (20-49 years).

RESULTS

Socially disadvantaged groups (low wealth, low education and indigenous ethnicity) had on average 15-21 (range across indicators and age groups) percentage points (pp) higher prevalence of stunting/short stature and 3-11 pp higher prevalence of anaemia. For overweight or obesity, adult women with low education had a 17 pp higher prevalence; differences were small among children <5 years, and results varied by country for adolescents by education, and for adults and adolescents by wealth and ethnicity. A moderate and strong correlation (-0·58 and -0·71) was only found between stunting/short stature prevalence and countries' GDP per capita and percentage of non-indigenous households.

CONCLUSIONS

Overweight was equally distributed among children; findings were mixed for ethnicity and wealth, whereas education was a protective factor among adult women. There is an urgent need to address the deep inequalities in undernutrition and prevent the emerging inequalities in excess weight from developing further.

Effect of Milk-Based Infant Formula Fortified with PUFAs on Lipid Profile, Growth and Micronutrient Status of Young Children: A Randomized Double-Blind Clinical Trial

BACKGROUND

Polyunsaturated fatty acids (PUFAs) are essential to child growth and development.

OBJECTIVE

To assess the effect of PUFAs-fortified infant formula on lipid profile, growth and micronutrient status in children 12 to 30 months old.

METHODS

This study is a double-blind randomized controlled clinical trial. Two study groups were assessed: (a) milk-based infant formula with micronutrients and PUFAs (PUFAs) and (b) milk-based infant formula with micronutrients, no PUFAs added (Non-PUFAs). Children received prepared formula (240 mL) twice a day, according to the color-code assigned to each infant. Anthropometric measurements and venous blood samples were taken at each day-care center at baseline, and again after four months. Total serum lipid extraction was 0.5 mL. Samples were treated and modified by the Folch method and analyzed with gas chromatography.

RESULTS

Changes in serum lipid profile (expressed as % FA) between baseline and four months showed a statistically significant increase in docosahexaenoic acid (DHA) (0.22 vs. -0.07, p < 0.05) and Alpha-Linoleic acid (0.08 vs. 0.02, p < 0.05) in infants who consumed PUFAs-fortified formula compared to Non-PUFAs-fortified formula. Infants increased their length/height-for-age Z-score: median change for the PUFAs group was 0.16 (95% CI = 0.08, 0.28) and 0.23 (95% CI = 0.14, 0.33) for Non-PUFAs, with no differences between groups. Median folate level was significantly higher among the PUFAs group compared to Non-PUFAs: -0.87 (95% CI = -1.38, -0.44) and -3.83 (95% CI = -4.65, -3.03) respectively. Consumption of both supplements was adequate and stable during the intervention.

CONCLUSION

A significant improvement was observed in the lipid profile of children who received the PUFAs-fortified milk-based formula.

The relationship between residential altitude and stunting: evidence from >26 000 children living in highlands and lowlands of Ethiopia

Little information is known about the influence of altitude on child growth in Ethiopia, where most people live in highlands. We investigated the relation of residential altitude with growth faltering (stunting) of infants and young children in Ethiopia. We also examined whether the altitude-growth relationship was independent of the influence of the dietary and non-dietary determinants of growth. We used the data of 26 976 under-5-year-old children included in the Ethiopian Demographic and Health Surveys, conducted from 2005 to 2016. The samples were recruited following a two-stage cluster sampling strategy. Stunting was defined by height-for-age <-2 z-scores. The relationship between residential altitude and stunting was examined by running multiple logistic regression analysis, controlling the effect of covariate dietary and non-dietary variables. The residential altitude of the study participants ranged from -116 to 4500 m above sea level (masl). There was a significant and progressive increase in the prevalence and odds of stunting with increasing altitude (P < 0·001), irrespective of the dietary and non-dietary predictors of stunting. The prevalence of stunting was lowest in lowlands (39 %) and highest in highlands (47 %). Compared with altitude <1000 masl, the odds of stunting was 1·41 times higher at altitude ≥2500 masl (OR 1·41, 95 % CI 1·16, 1·71) and 1·29 times higher at altitude 2000-2499 masl (OR 1·29, 95 % CI 1·11, 1·49). Children living in highlands might be at a higher risk of poor growth. Further studies are warranted to understand the mechanism behind the observed altitude-stunting link and identify strategies to compensate for the growth-faltering effect of living in highlands.

Hemoglobin levels and anemia evaluation among pregnant women in the remote and rural high lands of mid-western Nepal: a hospital based study

Background

Anemia though is a major risk factor for unfavorable pregnancy outcomes; no previous studies have yet described the hemoglobin (Hb) concentrations and anemia prevalence among pregnant women of remote mid western highlands of Nepal where the aggravating factors that increase the risk of anemia are very common. In addition, the physiological adaptive Hb rise to altitude was considered in the study while evaluating anemia. Thus, our primary objectives were to study the hemoglobin levels and prevalence of anemia among pregnant women of Jumla and its adjoining districts, and to assess the potential associations of hemoglobin and anemia with women’s characteristics.

Methods

The study was conducted in 319 singleton term non-smoker pregnant women who visited to the teaching hospital for delivery. Their blood samples were tested for Hb and related sociodemographic information was collected. One-way analysis of variance (ANOVA) and independent t-test were used to compare the mean Hb levels. Multiple linear regression model and multiple logistic regression model were used to assess the association of Hb level and anemia with pregnant women’s characteristics. The prevalence of anemia was calculated based on the altitude and pregnancy-adjusted Hb cut off value for anemia [{11+ adjustment factor (1.3)} gm./dl].

Results

The overall mean hemoglobin concentration was (13.497 ± 1.64) gm/dl, ranging from 8 to 19.20 g/dl. The pregnant women Hb level showed significant association with their age (Coeff = 0.059; 95% CI: 0.011, 0.106; p = 0.015) and parity (Coeff = − 0.21; 95% CI: − 0.382, − 0.038; p = 0.017). The overall prevalence of anemia in the study population was 17.9% (57/319), which varied with age, parity and ethnicity. The disadvantaged Janajatis were more likely (OR = 4.615, 95% CI: 1.48, 14.35, p = 0.008) to have anemia compared to upper cast group.

Conclusion

The mean Hb concentration was high and prevalence rate of anemia was low among pregnant women in karnali zone compared to average Nepali pregnant women. Women’s age and parity were significant predictors of Hb level. Ethnicity, however, was associated with the occurrence of anemia.

Malnutrition prevalence among children and women of reproductive age in Mexico by wealth, education level, urban/rural area and indigenous ethnicity

OBJECTIVE

To compare the prevalence of malnutrition (undernutrition and excess weight) by wealth, education level, ethnicity and urban/rural areas in Mexican children and women of reproductive age.

DESIGN

We compared the prevalence of overweight, obesity, wasting/underweight, stunting/short stature and anaemia by socioeconomic and ethnic indicators. For each indicator, we estimated prevalence ratios (PR) adjusted by all other socioeconomic and ethnic indicators. We analysed if results differed by urban/rural areas.

SETTING

Mexican National Health and Nutrition Survey 2012.

PARTICIPANTS

Children <5 years, non-pregnant women 11-19 years and non-pregnant women 20-49 years (n 33 244).

RESULTS

In most age groups, belonging to non-indigenous households, with high wealth, high education and in urban areas were inversely associated with stunting or short stature (PR ranging from 0·40 to 0·83), and wealth and education were inversely associated with anaemia (PR ranging from 0·53 to 0·78). The prevalence of overweight was similar across subgroups among children <5 years; however, among women 11-19 years, wealth, non-indigenous household and urban areas were positively associated (PR ranging from 1·16 to 1·33); and among women 20-49 years, education was inversely associated (PR 0·83).

CONCLUSIONS

Socially disadvantaged populations have a higher prevalence of undernutrition, whereas the prevalence of excess weight is either equal (children <5 years), slightly lower (women 11-19 years) or even higher (women 20-49 years) with lower education. These results highlight the need for specific actions to address social inequalities in malnutrition in the Mexican population.

Low Serum B12 Concentrations Are Associated with Low B12 Dietary Intake But Not with Helicobacter pylori Infection or Abnormal Gastric Function in Rural Mexican Women

Background: Gastric function, Helicobacter pylori infection, and vitamin B12 (B12) dietary intake were assessed as predictors of serum B12. Methods: H. pylori antibodies, gastric function, B12 dietary intake, and biochemical/hematological parameters were measured in 191 adult women from two rural communities in Querétaro, Mexico. Results: The overall mean serum B12 concentration was 211 ± 117 pmol/L. The prevalences of low (≤ 148 pmol/L), marginal (148 to 221 pmol/L), and adequate (> 221 pmol/L) serum B12 were 28.4%, 31.1%, and 40.5%, respectively. Seventy-one percent of women tested positive for H. pylori antibodies. The prevalence of gastric function categories did not differ by serum B12 categories. The odds ratio for having low serum B12 was 2.7 (p = 0.01) for women with an intake below the estimated average requirement, 3.6 (p = 0.01) for those in the lowest tertile of total B12 intake, and 3.0 (p = 0.02) for those in the lowest tertile of B12 intake from animal source foods. Age and B12 intake were predictors of serum B12 concentrations [serum B12 (pmol/L) = 90.060 + 5.208 (B12 intake, µg/day) + 2.989 (age, years). Conclusions: Low serum B12 concentrations were associated with low B12 dietary intake but not with H. pylori infection or abnormal gastric function in rural Mexican women.

Translating Evidence-Based Program Recommendations into Action: The Design, Testing, and Scaling Up of the Behavior Change Strategy EsIAN in Mexico

BACKGROUND

The Integrated Strategy for Attention to Nutrition (EsIAN in Spanish) is a national strategy within Mexico's conditional cash transfer program (initially Progresa, then Oportunidades, then Prospera, CCT-POP) designed to strengthen the health and nutrition component, address the nutrition transition, and improve the health and nutritional status of its beneficiaries, through 3 main components: 1) procurement of functioning equipment to primary health care (PHC) units; 2) providing free micronutrient supplements to beneficiary women and children; 3) implementing a behavior change communication (BCC) strategy and a training system for PHC providers (PHCPs).

OBJECTIVE

We aim to describe the iterative process and evidence-based approach used to design and roll-out the EsIAN at scale, by focusing on the BCC component.

METHODS

The BCC strategy was developed by following an iterative process through the following phases: situational analysis, formative research and design of the BCC strategy (using the socioecological framework and the social marketing approach), large-scale feasibility study, redesign, and national scale-up.

RESULTS

The review and formative research revealed several barriers and issues that limited program coverage, utilization, and acceptance. These included misconceptions about pregnancy and infant feeding, nonalignment of practices with international recommendations, and lack of knowledge on nutrition and related topics, among others. These results were used to identify priority behaviors and elaborate key messages for mothers/caregivers and providers to develop the BCC strategy. The feasibility study resulted in significant improvements in PHCPs' knowledge, counseling (breastfeeding, and supplement use and consumption), and caregivers' complementary feeding behaviors, and highlighted several design and delivery aspects that needed strengthening. Based on these findings, the BCC strategy was adapted prior to a national scale-up.

CONCLUSIONS

The theory-based iterative approach resulted in the identification of specific actions to target, and approaches to do so, as part of the design and roll-out of the BCC strategy at scale.

A Fortified Food Can Be Replaced by Micronutrient Supplements for Distribution in a Mexican Social Protection Program Based on Results of a Cluster-Randomized Trial and Costing Analysis

BACKGROUND

Despite positive nutrition impacts, the prevalence of malnutrition among beneficiaries of Mexico's conditional cash transfer (CCT) program remains high. Greater nutrition impact may have been constrained by the type of nutritional supplements provided.

OBJECTIVE

The objective of this study was to inform a potential modification to the supplements distributed to pregnant and lactating women and children.

METHODS

Impact was assessed using 2 cluster-randomized trials (pregnant women, children) run simultaneously. Communities (n = 54) were randomly assigned to the fortified foods provided by the program (Nutrivida women, Nutrisano children) or alternatives: tablets (women), syrup (children), or micronutrient powders for women (MNP-W) and children (MNP-C). Each supplement for women/children contained the same micronutrients based on the formulations of Nutrivida and Nutrisano, respectively. Pregnant women (aged >18 y) were recruited before 25 weeks of gestation and followed to 3 mo postpartum. Children aged 6-12 mo were recruited and followed to age 24 mo. Primary outcomes were anemia for women and length growth for children. Statistical analyses appropriate for cluster-randomized designs were used, and structural equation modeling to estimate dose-response effects. Supplement costs per beneficiary (daily dose for 18 mo) were estimated for production and distribution.

RESULTS

There was no significant difference in change of anemia prevalence between supplement groups in women, or in length growth between groups in children. One daily dose of any supplement was associated with 0.8 cm greater length growth. From baseline to age 24 mo, the prevalence of anemia in the Nutrisano, syrup, and MNP-C groups decreased by 36.7, 40.8, and 37.9 percentage points, respectively (within-group, P < 0.05; between groups, P > 0.05). Costs per beneficiary ranged from $12.1 (MNP-C) to $94.8 (Nutrivida).

CONCLUSIONS

The CCT program could distribute alternative supplements at lower cost per beneficiary without compromising potential for impact. Acceptance among beneficiaries should also be considered in choice of alternatives. This trial was registered at www.clinicaltrials.gov as NCT00531674.

Malnutrition in all its forms and socio-economic indicators in Argentina

OBJECTIVE

To assess the prevalence of five forms of malnutrition (wasting/underweight, overweight, obesity, stunting/short stature and anaemia) by socio-economic wealth (SEW) and educational level (EL) among children, adolescents and women of reproductive age in Argentina.

DESIGN

Analysis from a cross-sectional survey. Anthropometric indicators and prevalence of anaemia were estimated. SEW was classified according to the proportion of contributors in the household, employment status, EL and medical coverage. EL was categorized by years of formal education.

SETTING

National Health and Nutrition Survey, 2005.

PARTICIPANTS

Children (n 27 015) <5 years, adolescent girls (n 1729) 11-19 years, women (n 4401) 20-49 years.

RESULTS

In Argentina, 26 % of households lived with unsatisfied basic needs and 23 % received at least one form of food assistance. Any form of malnutrition affected 23 % of children, 36 % of girls and 56 % of women. Children were especially affected by anaemia, overweight/obesity and stunting (15·2, 9·9, 7·4 %, respectively). Girls were affected by overweight/obesity, anaemia and stunting (22·5, 15·2, 6·2 %). Women were strongly affected by overweight/obesity, anaemia and stunting (43·8, 19·8, 10·5 %). Stunting or short stature was higher in low-SEW settings, doubling in prevalence between low and high levels, increasing four times among women in reproductive age (P < 0·05). Excess weight among children was higher in high-SEW settings, in women the tendency was inverse. Anaemia showed different tendency according to SEW.

CONCLUSIONS

In 2005, Argentina had high rates of excess weight and anaemia, moderate prevalence of stunting and low frequency of wasting/underweight. All forms of malnutrition showed a strong relationship with socio-economic and educational inequality.

Household food insecurity and its association with anaemia in Mexican children: National Health and Nutrition Survey 2012

OBJECTIVES

To assess the association between household food insecurity (FI) and the presence of anaemia among Mexican children who were between 12 and 59 months old, and to determine whether this association differs by geographical regions.

METHODS

We analysed 7468 children of ages between 12 and 59 months, based on data from the 2012 National Health and Nutrition Survey (ENSANUT 2012). Haemoglobin was measured in capillary blood. Household FI levels were defined according to the Latin American and Caribbean Food Security Scale. An ordinal logistic regression model was developed to assess the relationship between FI and anaemia. The interaction between geographical regions and FI was determined.

RESULTS

The highest proportion of anaemia occurred in children with severe household FI (24.3%), compared to those from households with food security (21.2%). Children from severe FI households have a higher adjusted prevalence of anaemia than those from households with food security. FI and anaemia were associated mainly among children residing in the southern region of Mexico.

CONCLUSIONS

Our findings can contribute to a better understanding of FI and anaemia in children and to strengthen interventions to address these problems.

Physiologically driven, altitude-adaptive model for the interpretation of pediatric oxygen saturation at altitudes above 2,000 m a.s.l

Measuring peripheral oxygen saturation (SpO2) with pulse oximeters at the point of care is widely established. However, since SpO2 is dependent on ambient atmospheric pressure, the distribution of SpO2 values in populations living above 2000 m a.s.l. is largely unknown. Here, we propose and evaluate a computer model to predict SpO2 values for pediatric permanent residents living between 0 and 4,000 m a.s.l. Based on a sensitivity analysis of oxygen transport parameters, we created an altitude-adaptive SpO2 model that takes physiological adaptation of permanent residents into account. From this model, we derived an altitude-adaptive abnormal SpO2 threshold using patient parameters from literature. We compared the obtained model and threshold against a previously proposed threshold derived statistically from data and two empirical data sets independently recorded from Peruvian children living at altitudes up to 4,100 m a.s.l. Our model followed the trends of empirical data, with the empirical data having a narrower healthy SpO2 range below 2,000 m a.s.l. but the medians never differed more than 2.3% across all altitudes. Our threshold estimated abnormal SpO2 in only 17 out of 5,981 (0.3%) healthy recordings, whereas the statistical threshold returned 95 (1.6%) recordings outside the healthy range. The strength of our parametrized model is that it is rooted in physiology-derived equations and enables customization. Furthermore, as it provides a reference SpO2, it could assist practitioners in interpreting SpO2 values for diagnosis, prognosis, and oxygen administration at higher altitudes.NEW & NOTEWORTHY Our model describes the altitude-dependent decrease of SpO2 in healthy pediatric residents based on physiological equations and can be adapted based on measureable clinical parameters. The proposed altitude-specific abnormal SpO2 threshold might be more appropriate than rigid guidelines for administering oxygen that currently are only available for patients at sea level. We see this as a starting point to discuss and adapt oxygen administration guidelines.

Nutrition-specific and nutrition-sensitive factors associated with mid-upper arm circumference as a measure of nutritional status in pregnant Ethiopian women: Implications for programming in the first 1000 days

Poor nutritional status in pregnancy expressed as low mid-upper arm circumference (MUAC) is associated with low birth weight. The study aims were to assess the nutritional status of pregnant Ethiopian women using MUAC and examine association with nutrition-specific and nutrition-sensitive factors, using baseline data of a prospective longitudinal observational birth cohort study conducted in three rural districts in the Oromia region of Ethiopia. Recruitment into the cohort was rolling over a period of nine months, and the data used for this analysis were collected while the women were between 12-32 weeks of gestation. Detailed household socio-demographics, agricultural production, women's health, morbidity and diets, with weights, heights and MUAC, and anemia prevalence (HemoCue) were collected. The prevalence of low MUAC (< 23 cm) was 41%. Controlling for location and clustering, wealth quintile (OR = 0.88, CI = 0.82 to 0.96, p<0.01) was associated with decreased risk of low MUAC, while trimester (OR = 1.31, CI = 1.16 to 1.48, p<0.001) was associated with increased risk of low MUAC. The only significant factor amenable to nutrition-specific interventions was altitude-adjusted anemia, which was associated with increased risk of low MUAC (OR = 1.28, CI = 1.09 to 1.49, p<0.01). Significant factors amenable to nutrition-sensitive factors and associated with higher odds of low MUAC were household food insecurity (OR = 1.04, CI = 1.02 to 1.06, p<0.001), distance to the clinic in minutes (OR = 1.01, CI = 1.0 to 1.01, p<0.0001) and season of recruitment (lean versus non lean) (OR = 1.30, CI = 1.10 to 1.54, p<0.01). Literacy (OR = 0.85, CI = 0.74 to 0.98, p<0.05) and numeracy (OR = 0.75, CI = 0.62 to 0.91, p<0.01) were also significantly associated with lower odds of low MUAC. Poor nutritional status in pregnancy expressed as percent with low MUAC was high in Ethiopian women. It was associated with several nutrition-specific and -sensitive factors indicating the importance of multisectoral actions in improving outcomes within the first 1000 days.

A Randomized Feeding Trial of Iron-Biofortified Beans on School Children in Mexico

Iron deficiency is a major public health problem worldwide, with the highest burden among children. The objective of this randomized efficacy feeding trial was to determine the effects of consuming iron-biofortified beans (Fe-Beans) on the iron status in children, compared to control beans (Control-Beans). A cluster-randomized trial of biofortified beans (Phaseolus vulgaris L.), bred to enhance iron content, was conducted over 6 months. The participants were school-aged children (n = 574; 5–12 years), attending 20 rural public boarding schools in the Mexican state of Oaxaca. Double-blind randomization was conducted at the school level; 20 schools were randomized to receive either Fe-Beans (n = 10 schools, n = 304 students) or Control-Beans (n = 10 schools, n = 366 students). School administrators, children, and research and laboratory staff were blinded to the intervention group. Iron status (hemoglobin (Hb), serum ferritin (SF), soluble transferrin receptor (sTfR), total body iron (TBI), inflammatory biomarkers C-reactive protein (CRP) and α-1-acid glycoprotein (AGP)), and anthropometric indices for individuals were evaluated at the enrollment and at the end of the trial. The hemoglobin concentrations were adjusted for altitude, and anemia was defined in accordance with age-specific World Health Organization (WHO) criteria (i.e., Hb <115 g/L for <12 years and Hb <120 g/L for ≥12 years). Serum ferritin concentrations were adjusted for inflammation using BRINDA methods, and iron deficiency was defined as serum ferritin at less than 15.0 µg/L. Total body iron was calculated using Cook’s equation. Mixed models were used to examine the effects of Fe-Beans on hematological outcomes, compared to Control-Beans, adjusting for the baseline indicator, with school as a random effect. An analysis was conducted in 10 schools (n = 269 students) in the Fe-Beans group and in 10 schools (n = 305 students) in the Control-Beans group that completed the follow-up. At baseline, 17.8% of the children were anemic and 11.3% were iron deficient (15.9%, BRINDA-adjusted). A total of 6.3% of children had elevated CRP (>5.0 mg/L), and 11.6% had elevated AGP (>1.0 g/L) concentrations at baseline. During the 104 days when feeding was monitored, the total mean individual iron intake from the study beans (Fe-bean group) was 504 mg (IQR: 352, 616) over 68 mean feeding days, and 295 mg (IQR: 197, 341) over 67 mean feeding days in the control group (p < 0.01). During the cluster-randomized efficacy trial, indicators of iron status, including hemoglobin, serum ferritin, soluble transferrin receptor, and total body iron concentrations improved from the baseline to endline (6 months) in both the intervention and control groups. However, Fe-Beans did not significantly improve the iron status indicators, compared to Control-Beans. Similarly, there were no significant effects of Fe-Beans on dichotomous outcomes, including anemia and iron deficiency, compared to Control-Beans. In this 6-month cluster-randomized efficacy trial of iron-biofortified beans in school children in Mexico, indicators of iron status improved in both the intervention and control groups. However, there were no significant effects of Fe-Beans on iron biomarkers, compared to Control-Beans. This trial was registered at clinicaltrials.gov as NCT03835377.

[Trend in the prevalence of anemia in Mexican women of childbearing age from 2006-2016. Ensanut MC 2016]

OBJECTIVE

To describe the anemia prevalence among women from 20 to 49 years from 2016-Halfway National Health and Nutrition Survey (Ensanut MC 2016) and compare the trends in 2006, 2012 and 2016 surveys, as well as its association with dietary iron and sociodemographic factors.

MATERIALS AND METHODS

The methodological design of Ensanut MC is fully comparable with Ensanut 2006 and 2012. Capillary hemoglobin (Hb) was obtained and those values <120 g/L were classified as anemic. Pregnant women were excluded from the analysis.

RESULTS

Anemia prevalence is higher in Ensanut MC 2016 when compared with Ensanut 2012 (p<0.001), differences can be found by age-groups, locality (urban-rural) and country region (North, Center, Mexico City and South). Logistic model showed an increase in anemia prevalence in 2016.

CONCLUSIONS

Anemia decreas from 2006 to 2012 was followed by an increas in 2016. It is necessary to identify potential risk factors that could be promoting anemia prevalence rising as well as estimate the iron-rich foods intake whit 24 hours recall.

Burden and determinants of undernutrition among young pregnant women in Ethiopia

Undernutrition is a major public health concern due to its association with the mortality and disease burden of women and children. This study aimed at identifying the extent and determinants of undernutrition among young pregnant women in Ethiopia. A multivariable regression analysis was fitted to identify determinants of undernutrition and anaemia in a sample of 1,393 pregnant women. Risk ratios (RRs) with 95% confidence interval (CI) were estimated. All the analyses were performed using STATA version 14 and adjusted for clustering. The study revealed that 38% of the women were undernourished and 22% were anaemic. Improved maternal education, RR = 0.94, 95% CI [0.89, 0.98]; higher wealth status, RR = 0.72, 95% CI [0.47, 0.95]; higher minimum dietary diversity for women, RR = 0.87, 95% CI [0.77, 0.98]; increased maternal height, RR = 0.96, 95% CI [0.94, 0.98]; and protected water source, RR = 0.93, 95% CI [0.86, 0.96], have decreased the risk of undernutrition while using unimproved toilet, RR = 1.31, 95% CI [1.06, 1.63], and depression, RR = 1.33, 95% CI [1.14, 1.55], increased the risk of anaemia. Animal source food consumption decreased both the risk of undernutrition, RR = 0.85, 95% CI [0.77, 0.94], and anaemia, RR = 0.91, 95% CI [0.85, 0.95]. The burden of undernutrition is still high. Although improved socio-economic status and dietary practices decreased the risk of undernutrition, poor health and environmental conditions were still significant risk factors. These findings suggest the need to target this set of important determinants to significantly decrease the burden of undernutrition among young pregnant women.

Peri-Urban, but Not Urban, Residence in Bolivia Is Associated with Higher Odds of Co-Occurrence of Overweight and Anemia among Young Children, and of Households with an Overweight Woman and Stunted Child

Background

Urban populations have grown globally alongside emerging simultaneous burdens of undernutrition and obesity. Yet, how heterogeneous urban environments are associated with this nutritional double burden is poorly understood.

Objective

We aimed to determine: 1) the prevalence of the nutritional double burden and its components in urban, peri-urban, and rural areas of Bolivia; and 2) the association of residence in these areas with the nutritional double burden and its components.

Design

We surveyed 3946 randomly selected households from 2 metropolitan regions of Bolivia. Census data and remotely sensed imagery were used to define urban, peri-urban, and rural districts along a transect in each region. We defined 5 nutritional double burdens: concurrent overweight and anemia among women of reproductive age (15-49 y), and children (6-59 mo), respectively; concurrent overweight and stunting among children; and households with an overweight woman and, respectively, an anemic or stunted child. Capillary hemoglobin concentrations were measured to assess anemia (women: hemoglobin <120 g/L; children: hemoglobin <110 g/L), and overweight and stunting were calculated from height, weight, and age data.

Results

In multiple logistic regression models, peri-urban, but not urban residence, was associated with higher odds of concurrent overweight and anemia among children (OR: 1.8; 95% CI; 1.0, 3.2) and of households with an overweight woman and stunted child (1.8; 1.2, 2.7). Examining the components of the double burden, peri-urban women and children, respectively, had higher odds of overweight than rural residents [women (1.5; 1.2, 1.8); children (1.5; 1.0, 2.4)], and children from peri-urban regions had higher odds of stunting (1.5; 1.1, 2.2).

Conclusions

Peri-urban, but not urban, residence in Bolivia is associated with a higher risk of the nutritional double burden than rural areas. Understanding how heterogeneous urban environments influence nutrition outcomes could inform integrated policies that simultaneously address both undernutrition and obesity.

Using a monitoring and evaluation framework to improve study efficiency and quality during a prospective cohort study in infants receiving rotavirus vaccination in El Alto, Bolivia: the Infant Nutrition, Inflammation, and Diarrheal Illness (NIDI) study

BACKGROUND

Implementing rigorous epidemiologic studies in low-resource settings involves challenges in participant recruitment and follow-up (e.g., mobile populations, distrust), biological sample collection (e.g., cold-chain, laboratory equipment scarcity) and data collection (e.g., literacy, staff training, and infrastructure). This article describes the use of a monitoring and evaluation (M&E) framework to improve study efficiency and quality during participant engagement, and biological sample and data collection in a longitudinal cohort study of Bolivian infants.

METHODS

The study occurred between 2013 and 2015 in El Alto, Bolivia, a high-altitude, urban, low-resource community. The study's M&E framework included indicators for participant engagement (e.g., recruitment, retention, safety), biological sample (e.g., stool and blood), and data (e.g., anthropometry, questionnaires) collection and quality. Monitoring indicators were measured regularly throughout the study and used for course correction, communication, and staff retraining.

RESULTS

Participant engagement indicators suggested that enrollment objectives were met (461 infants), but 15% loss-to-follow-up resulted in only 364 infants completing the study. Over the course of the study, there were four study-related adverse events (minor swelling and bruising related to a blood draw) and five severe adverse events (infant deaths) not related to study participation. Biological sample indicators demonstrated two blood samples collected from 95% (333 of 350 required) infants and stool collected for 61% of reported infant diarrhea episodes. Anthropometry data quality indicators were extremely high (median SDs for weight-for-length, length-for-age and weight-for-age z-scores 1.01, 0.98, and 1.03, respectively), likely due to extensive training, standardization, and monitoring efforts.

CONCLUSIONS

Conducting human subjects research studies in low-resource settings often presents unique logistical difficulties, and collecting high-quality data is often a challenge. Investing in comprehensive M&E is important to improve participant recruitment, retention and safety, and sample and data quality. The M&E framework from this study can be applied to other longitudinal studies.

Household food insecurity in Mexico is associated with the co-occurrence of overweight and anemia among women of reproductive age, but not female adolescents

We aimed to determine the association between household food insecurity (HFI) and the co-occurrence of overweight and anemia among women of reproductive age in the Mexican population. We analyzed data on 4,039 nonpregnant female adolescents (15-19 years) and 10,760 nonpregnant adult women of reproductive age (20-49 years) from the 2012 National Health and Nutrition Survey of Mexico. The survey uses a two-stage sampling design, stratified by rural and urban regions. The Latin American and Caribbean Food Security Scale was used to assess HFI. We assessed overweight and obesity in women based on World Health Organization classifications for body mass index, and BMI-for-age Z-scores for female adolescents, and defined anemia as an altitude-adjusted hemoglobin (Hb) concentration < 120 g/L based on measurement of capillary Hb concentrations. In multiple logistic regression models adjusting for potential confounding covariates, HFI was not associated with the co-occurrence of anemia and overweight among female adolescents. The adjusted odds of women of reproductive age from mildly and moderately food-insecure households, respectively, experiencing concurrent anemia and overweight were 48% (OR: 1.48; 95% CI: 1.15, 1.91) and 49% (OR: 1.49; 95% CI: 1.08, 2.06) higher than among women from food-secure households. Severe HFI was not associated with concurrent overweight and anemia among female adolescents or women. HFI may be a shared mechanism for dual forms of malnutrition within the same individual, simultaneously contributing to overconsumption and dietary inadequacy.

Predictors of anemia in pregnant women residing in rural areas of the Oromiya region of Ethiopia

Background

Anemia in pregnancy is associated with higher risk of low birth weight and both maternal and perinatal mortality. While previous studies in Ethiopia have examined factors associated with anemia, which factors are the most important determinants of anemia in this population remain unclear. The objective of this study was to examine the association between anemia status in pregnant women with different health, behavioral, and socioeconomic factors in Oromiya province of Ethiopia.

Methods

This study used pregnancy enrollment data from a longitudinal birth cohort study conducted in Ethiopia. Survey data on maternal and household characteristics were collected at enrollment and maternal hemoglobin levels were measured. The analysis includes 4600 pregnant women. Logistic regression models were used to identify factors associated with maternal anemia in pregnancy.

Results

Controlling for geographic location and religion, low maternal MUAC and previous pregnancies were associated with increased odds of anemia, with odds ratios of 1.30 (p < 0.001, CI 1.12-1.51), and 1.50 (p = 0.002, CI 1.16-1.95), respectively. For each additional point on the handwashing score scale, the odds of being anemic were reduced by 12% (p < 0.001, CI 0.82-0.94). Numerate women compared to non-numerate women had 30% lower odds (p < 0.001, CI 0.57-0.85).

Conclusion

Controlling for woreda and religion, low maternal MUAC, and previous pregnancy increased odds of anemia while numeracy and better handwashing practices significantly reduced the odds of anemia in pregnancy. Further investigation is needed to determine the cause of anemia in pregnant women in Oromiya and to determine the effects of maternal anemia on birth outcomes.

Food assistance programmes are indirectly associated with anaemia status in children <5 years old in Mexico

Anaemia in children is a public health concern in Mexico; Federal food assistance programmes are being implemented to prevent it. We undertook this research to investigate the indirect association between food assistance programmes (FAP) and anaemia through dietary and socio-economic conditions of beneficiary children. A structural equation model (SEM) was constructed to assess associations among FAP, dietary and socio-economic conditions, as well as anaemia. A cross-sectional comparative study was conducted based on a sample of 1214 households with children <5 years old, beneficiaries of two FAP:Prosperaand rescue from malnutrition with amaranth (RMA) and a comparison group in San Luis Potosí, Mexico. The SEM and a decomposition effect analysis revealed the existence of a significant indirect association of FAP on the prevalence of anaemia via dietary and socio-economic conditions in children under 5 years old. TheProsperaassistance programme showed a significant indirect positive association with the prevalence of anaemia (standard coefficient=0·027,P<0·031), and the RMA programme showed a significant indirect negative association with the prevalence of anaemia (standard coefficient=−0·029,P=0·047). There was a direct association between FAP and dietary and socio-economic conditions. FAP could indirectly modify the prevalence of anaemia in young children with a direct improvement on dietary and socio-economic conditions. The unexpected finding of the association between RMA, dietary and socio-economic conditions and the prevalence of anaemia reflects differences in the focus of the programmes.

Systematic Review and Meta-Analysis of Method Comparison Studies of Masimo Pulse Co-Oximeters (Radical-7™ or Pronto-7™) and HemoCue® Absorption Spectrometers (B-Hemoglobin or 201+) with Laboratory Haemoglobin Estimation

We assessed agreement in haemoglobin measurement between Masimo pulse co-oximeters (Rad-7™ and Pronto-7™) and HemoCue® photometers (201+ or B-Hemoglobin) with laboratory-based determination and identified 39 relevant studies (2915 patients in Masimo group and 3084 patients in HemoCue group). In the Masimo group, the overall mean difference was -0.03 g/dl (95% prediction interval -0.30 to 0.23) and 95% limits of agreement -3.0 to 2.9 g/dl compared to 0.08 g/dl (95% prediction interval -0.04 to 0.20) and 95% limits of agreement -1.3 to 1.4 g/dl in the HemoCue group. Only B-Hemoglobin exhibited bias (0.53, 95% prediction interval 0.27 to 0.78). The overall standard deviation of difference was larger (1.42 g/dl versus 0.64 g/dl) for Masimo pulse co-oximeters compared to HemoCue photometers. Masimo devices and HemoCue 201+ both provide an unbiased, pooled estimate of laboratory haemoglobin. However, Masimo devices have lower precision and wider 95% limits of agreement than HemoCue devices. Clinicians should carefully consider these limits of agreement before basing transfusion or other clinical decisions on these point-of-care measurements alone.

Evaluation of hemoglobin concentration in pregnancy and correlation with different altitude: a study from balochistan plateau of pakistan

BACKGROUND

Anemia refers to a condition having low hemoglobin concentration. Anemia is considered a major risk factor for unfavorable pregnancy outcomes. This is the first study describing the pattern of hemoglobin concentration during pregnancy and its relationship to areas of high and low altitudes in Balochistan (the largest of Pakistan's four provinces). The main objective of this study was to observe hemoglobin levels and prevalence of anemia among pregnant women living in the high or low altitude areas of Balochistan.

METHODS

A randomized survey was conducted and blood samples were collected from 132 healthy full term pregnant women subjects and 110 unmarried females. The subjects of the current study were selected from two different areas of Balochistan (Quetta and Uthal). Hemoglobin levels of the subjects were analyzed on Microlab 300 by Merck kit. Dietary status of the subjects was assessed based on simplified associated food frequency questionnaire. The factors effecting hemoglobin in full term pregnancy at different altitudes were multi gravidity/parity (increased number of pregnancies/children), age, socio-economic and educational status.

RESULTS

Anemia was highly prevalent in low-altitude region (68.33%). We found statistically significant difference in mean hemoglobin level at high-altitude region (11.81 ± 1.02) and low-altitude region (10.20 ± 1.28) in pregnant females of Balochistan plateau (P < 0.001). Higher maternal age (> 35 years) has shown significantly higher anemic frequency at both high (57.89%; p < 0.002) and low (41.46%; p = 0.067) altitudes. A balanced-diet that is rich in meat products has also shown significant correlation with reduced incidences of anemia among pregnant women at both altitudes.

CONCLUSION

Hemoglobin concentration increases in the body with elevated altitudes and, thus, anemia was less frequent at high-altitude region. Factors affecting hemoglobin concentration in full term pregnancy at different altitudes included old maternal age, low body-mass index, education and diet.

Household food insecurity is associated with anemia in adult Mexican women of reproductive age

BACKGROUND

Anemia is a major cause of maternal mortality. Household food insecurity (HFI) may increase the risk of anemia among women of reproductive age although this hypothesis remains largely untested in representative samples from low- and middle-income countries.

OBJECTIVE

Our objective was to investigate the association of HFI with anemia in a nationally representative, cross-sectional sample of Mexican women of reproductive age (12-49 y old).

METHODS

We tested the association between HFI and anemia among 16,944 women of reproductive age using the multiple logistic regression among adolescent (12-20 y) and adult women (21-49 y). HFI was measured with the use of the Latin American and Caribbean Food Security Scale. Hemoglobin was measured with capillary hemoglobin with the use of HemoCue photometer (HemoCue, Inc.) and anemia was defined with the use of WHO standards.

RESULTS

The association of HFI and anemia was not significant (P > 0.05) for adolescent women (12-20 y), whereas in adult women (21-49 y), the adjusted odds of having anemia were 31-43% higher among those living in mild to severely food insecure households than adult women residing in food secure households (P < 0.05).

CONCLUSIONS

HFI is associated with anemia among adult Mexican women. Programs that reduce HFI may also be effective at reducing the risk of anemia among Mexican women.

Effect of supplementation with ferrous sulfate or iron bis-glycinate chelate on ferritin concentration in Mexican schoolchildren: a randomized controlled trial

Background

Iron deficiency is one of the most common nutritional deficiencies worldwide. It is more prevalent when iron requirements are increased during pregnancy and during growth spurts of infancy and adolescence. The last stage in the process of iron depletion is characterized by a decrease in hemoglobin concentration, resulting in iron deficiency anemia. Iron deficiency, even before it is clinically identified as anemia, compromises the immune response, physical capacity for work, and intellectual functions such as attention level. Therefore, interventions addressing iron deficiency should be based on prevention rather than on treatment of anemia. The aim of this study was to compare short- and medium-term effects on ferritin concentration of daily supplementation with ferrous sulfate or iron bis-glycinate chelate in schoolchildren with iron deficiency but without anemia.

Methods

Two hundred schoolchildren from public boarding schools in Mexico City who had low iron stores as assessed by serum ferritin concentration but without anemia were randomly assigned to a daily supplement of 30 mg/day of elemental iron as ferrous sulfate or iron bis-glycinate chelate for 12 weeks. Iron status was evaluated at baseline, one week post-supplementation (short term), and 6 months (medium term) after supplementation.

Results

Ferritin concentration increased significantly between baseline and post-supplementation as well as between baseline and 6 months after supplementation. One week post-supplementation no difference was found in ferritin concentration between iron compounds, but 6 months after supplementation ferritin concentration was higher in the group that received bis-glycinate chelate iron. However, there is no difference in the odds for low iron storage between 6 months after supplementation versus the odds after supplementation; nor were these odds different by type of supplement. Hemoglobin concentration did not change significantly in either group after supplementation.

Conclusions

Supplementing with 30 mg/d of elementary iron, either as ferrous sulfate or iron bis-glycinate chelate for 90 days, showed positive effects on increasing ferritin concentration in schoolchildren with low iron stores, and this effect persisted 6 months after supplementation.

Short-Term Impact of Anemia on Mortality

Objective: To estimate the short-term (14 months) impact of anemia on mortality among Mexican older adults (OAs). Method: Longitudinal analyses using data from a quasi-experimental study in a non-contributory pension program in Mexico with a sample of 3,621 OAs aged 65 to 74 years. Data on health, nutrition, life conditions, and mortality were gathered at both baseline and follow-up. Logistic regression model was used to estimate the impact of anemia and hemoglobin quintiles on mortality. Results: Overall mortality rate was 2.1%. Both mild anemia and moderate/severe anemia increased mortality risk at 14 months (odds ratio [OR] = 2.04, 95% confidence interval [CI] = [1.1, 4.1]; and OR = 6, 95% CI = [2.1, 16.9], respectively). Discussion: In the short term, degree of severity of anemia is an independent predictor of mortality risk. Because anemia is a modifiable factor, further research is required to better understand this condition in terms of main causes, prevention, treatment, and impact on OAs’ survival.

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.

Administration of misoprostol by trained traditional birth attendants to prevent postpartum haemorrhage in homebirths in Pakistan: a randomised placebo-controlled trial

Objective

To determine if misoprostol is safe and efficacious in preventing postpartum haemorrhage (PPH) when administered by trained traditional birth attendants (TBA) at home deliveries.

Design

A randomised, double-blind, placebo-controlled trial.

Setting

Chitral, Khyber Pakhtunkhwa Province, Pakistan.

Population

A total of 1119 women giving birth at home.

Methods

From June 2006 to June 2008, consenting women were randomised to receive 600 μg oral misoprostol (n = 534) or placebo (n = 585) after delivery to determine whether misoprostol reduced the incidence of PPH (≥500 ml).

Main outcome measures

The primary outcomes were measured blood loss ≥500 ml after delivery and drop in haemoglobin >2 g/dl from before to after delivery.

Results

Oral misoprostol was associated with a significant reduction in the rate of PPH (≥500 ml) (16.5 versus 21.9%; relative risk 0.76, 95% CI 0.59–0.97). There were no measurable differences between study groups for drop in haemoglobin >2 g/dl (relative risk 0.79, 95% CI 0.62–1.02); but significantly fewer women receiving misoprostol had a drop in haemoglobin >3 g/dl, compared with placebo (5.1 versus 9.6%; relative risk 0.53, 95% CI 0.34–0.83). Shivering and chills were significantly more common with misoprostol. There were no maternal deaths among participants.

Conclusions

Postpartum administration of 600 μg oral misoprostol by trained TBAs at home deliveries reduces the rate of PPH by 24%. Given its ease of use and low cost, misoprostol could reduce the burden of PPH in community settings where universal oxytocin prophylaxis is not feasible. Continual training and skill-building for TBAs, along with monitoring and evaluation of programme effectiveness, should accompany any widespread introduction of this drug.

Trial registration

http://clinicaltrials.gov/NCT00120237 Misoprostol for the Prevention of Postpartum Hemorrhage in Rural Pakistan.

Effectiveness of a large-scale iron-fortified milk distribution program on anemia and iron deficiency in low-income young children in Mexico

BACKGROUND

Anemia during infancy impairs neurodevelopment. Little information has been published about the effectiveness of large-scale programs on anemia and iron-deficiency prevention.

OBJECTIVE

The objective was to assess the effectiveness of a large-scale program that distributes subsidized iron-fortified milk in Mexico on anemia and iron deficiency in children aged 12-30 mo.

DESIGN

A double-blinded, group-randomized effectiveness trial was conducted in 12 milk distribution clusters assigned to consume iron-fortified (FM; n = 7) or nonfortified (NFM; n = 5) milk. A daily portion of FM contained 5.28 mg Fe (ferrous gluconate) and 48 mg sodium ascorbate.

RESULTS

Overall treatment effects were documented at 6 and 12 mo for anemia and for iron deficiency assessed by both serum ferritin (SF) and serum soluble transferrin receptor (sTfR) (interaction: P < 0.10). Differential effects at 6 mo (P = 0.004) and 12 mo (P = 0.664) were documented only for sTfR. Estimated prevalences (EPs) of anemia (hemoglobin < 110 g/L) from baseline to 6 and 12 mo decreased from 42.6% to 19.7% and 9.4%, respectively, in the NFM group (n = 210) and from 44.5% to 12.7% and 4.0%, respectively, in the FM group (n = 357). EPs of SF < 12 mug/L from baseline to 6 and 12 mo changed from 36.0% to 41.8% and 17.1%, respectively, in the NFM group (n = 43) and from 29.8% to 18.6% and 5.7%, respectively, in the FM group (n = 144). EPs of sTfR > 3.3 mg/L from baseline to 6 and 12 mo decreased from 16.2% to 8.3% and 2.0%, respectively, in the NFM group (n = 114) and from 15.5% to 0.7% and 1.1%, respectively, in the FM group.

CONCLUSION

A large-scale iron-fortified subsidized-milk program was effective at reducing the rates of anemia and iron deficiency in Mexican children during 12 mo of implementation. This trial was registered at clinicaltrials.gov as NCT00508131.

Hemoglobin levels and anemia evaluation during pregnancy in the highlands of Tibet: a hospital-based study

Background

Anemia is regarded as a major risk factor for unfavorable pregnancy outcomes, but there have been no previous studies describing the pattern of hemoglobin concentration during pregnancy in Tibet and the relationship between altitude and Hb concentration in the pregnant women living in Tibet still has not been clearly established. The main objectives of this study were to study the hemoglobin levels and prevalence of anemia among pregnant women living in the highlands of Tibet and to evaluate potential associations of hemoglobin and anemia with women's characteristics.

Methods

The hospital-based study was conducted in 380 pregnant women. Their blood samples were tested and related sociodemographic information was collected. Multiple linear regression model and multiple logistic regression model were used to assess the association of pregnant women's characteristics with hemoglobin level and the occurrence of anemia. Centers for Disease Control (CDC), Dirren et al. and Dallman et al. methods were used to adjust the hemoglobin measurements based on altitude for estimating the prevalence of anemia.

Results

The mean hemoglobin concentration was 127.6 g/L (range: 55.0-190.0 g/L). Prevalence rate of anemia in this study was 70.0%, 77.9% and 41.3%, respectively for three altitude-correction methods for hemoglobin (CDC method, Dirren et al. method, and Dallman et al. method). Gestational age, ethnicity, residence and income were significantly associated with the hemoglobin concentration and prevalence of anemia in the study population. Specially, the hemoglobin concentration of pregnant women decreased with increase in gestational age.

Conclusion

The hemoglobin level was low and prevalence rate of anemia was high among pregnant women in Lhasa, Tibet. Gestational age, ethnicity, residence and income were found to be significantly associated with the hemoglobin level and the occurrence of anemia in the study population.

Maternal hemoglobin level and fetal outcome at low and high altitudes

Both, low (<7 g/dl) and high (>14.5 g/dl), maternal hemoglobin (Hb) levels have been related to poor fetal outcome. Most studies have been done at low altitude (LA). Here, we have sought to determine whether this relationship exists at both high and low altitude, and also whether there is an adverse effect of high altitude (HA) on fetal outcome independent of level of maternal hemoglobin. The study is based on a retrospective multicenter analysis of 35,449 pregnancies at LA and six other cities above 3000 meters. In analyses of all women at both LA and HA, those with Hb <9 g/dl had odds ratios (ORs) and 95% confidence intervals (CI) of 4.4 (CI: 2.8-6.7), 2.5 (CI: 1.9-3.2), and 1.4 (CI: 1.1-1.9) for stillbirths, preterm, and small for gestational age (SGA) births, respectively, compared with women with 11-12.9 g/dl of Hb, after adjustment for confounders. These risks by hemoglobin level differed little between women at LA and HA, suggesting that no correction of the definition of anemia is necessary for women at HA. Women living at high altitude with hemoglobin >15.5 g/dl had higher risks for stillbirths (OR: 1.3; CI: 1.05-1.3), preterm (OR: 1.5; CI 1.3-1.8), and SGA births (OR: 2.1, CI 1.8-2.3). There was also a significant adverse effect of living at HA, independent of hemoglobin level for all three outcomes (OR: 3.9, 1.7, and 2.3; CI: 2.8-5.2, 1.5-1.9, and 2.1-2.5) for stillbirths, preterms, and SGA respectively, after adjusting for hemoglobin level. Both, high and low maternal hemoglobin levels were related to poor pregnancy outcome, with similar effect of low hemoglobin in both LA and HA. Our data suggest, that maternal hemoglobin above 11 g/dl but below 13 g/dl is the area of minimal risk of poor adverse outcomes. Living at HA had an adverse effect independent of hemoglobin level.

Some indicators of nutritional status are associated with activity and exploration in infants at risk for vitamin and mineral deficiencies

Severe malnutrition, both protein-energy and micronutrient deficiency, results in decreased activity, but the results regarding mild-to-moderate malnutrition are equivocal. Our objective in this investigation was to describe the activity and exploratory behavior of Mexican infants and describe the relationship among nutritional status, activity, and exploration in this population at high risk for mild-to-moderate micronutrient deficiency, but at low risk for severe malnutrition. The participants were infants, 4-12 mo old, of low socioeconomic status from 3 states in southern Mexico. We measured anthropometrics using standard techniques. We measured hemoglobin (Hb) concentration in the field and adjusted values for altitude before analysis. We measured activity and exploration by direct observation during 15 min of individual play in a novel environment. Cluster analysis generated mutually exclusive activity clusters and exploration clusters based on patterns of bodily movement and exploratory behavior, respectively. We categorized the clusters as higher or lower activity or higher or lower exploration. A higher Hb concentration and height-for-age Z-score (HAZ) significantly increased the odds of being in the high-activity cluster. Iron deficiency, stunting, and wasting significantly decreased the odds of being in the high-activity cluster. Higher HAZ and weight-for-age Z-score significantly increased the odds of being in a higher exploration cluster. In Mexican infants at risk for mild-to-moderate micronutrient deficiency but at low risk of severe malnutrition, some indicators of nutritional status were related to increased activity and exploration.

Ferrous gluconate and ferrous sulfate added to a complementary food distributed by the Mexican nutrition program Oportunidades have a comparable efficacy to reduce iron deficiency in toddlers

OBJECTIVE

To assess the efficacy of ferrous sulfate (FS) and ferrous gluconate (FG) as fortificants for a complementary baby food (Nutrisano) to improve the iron status and to reduce the prevalence of anemia in toddlers.

PATIENTS AND METHODS

Toddlers 12 to 30 months old were randomly assigned to receive either of 3 versions of Nutrisano fortified with FS or FG or not fortified (CG) for 6 months. In final blood samples, the concentrations of hemoglobin, serum ferritin, and soluble transferrin receptors (sTfR) were determined. The effects of treatment on final hemoglobin, ferritin, and sTfR were assessed by multivariate analysis.

RESULTS

No significant changes in hemoglobin were observed within or among treatment groups. The prevalence of high sTfR decreased 7.1 percentage points in FG, increased 13.1 percentage points in FS, and increased 0.7 percentage points in CG (P>0.05). In an interaction between treatment and total intake of Nutrisano on the concentration of ferritin, sTfR, and total iron body stores, adjusted means of serum ferritin in the medium tertiles of intake of Nutrisano for FS (P=0.05) and in the higher and medium tertiles for FG were higher (P=0.001), and adjusted means of sTfR were significantly lower (P<0.001), than the respective lower tertile of intake.

CONCLUSIONS

Fortification of Nutrisano with FG has an acceptable level of beneficial effect on markers of iron status. The satisfactory efficacy and other sensory data has led to the political decision to substitute hydrogen-reduced iron, used formerly as a fortificant, with FG. Studies to assess the effectiveness of the reformulated Nutrisano are in order.

Fortifying milk with ferrous gluconate and zinc oxide in a public nutrition program reduced the prevalence of anemia in toddlers

We aimed to assess the efficacy of whole cow's milk fortified with ferrous gluconate and zinc oxide, along with ascorbic acid, in reducing the prevalence of anemia and improving iron status of low income children 10-30 mo of age. Healthy children were randomly assigned to drink 400 mL/d of cow's whole milk, either fortified milk (FM) with 5.8 mg/400 mL of iron as ferrous gluconate, 5.28 mg/400 mL of zinc as zinc oxide, and 48 mg/400 mL of ascorbic acid, or nonfortified milk (NFM) with 0.2 mg iron/400 mL, 1.9 mg zinc/400 mL, and 6.8 mg ascorbic acid/400 mL. Hemoglobin, serum ferritin, soluble transferrin receptors (TfR), and C-reactive protein concentrations were measured at baseline and 6 mo after intervention. The prevalence of anemia declined from 41.4 to 12.1% (P < 0.001), or 29 percentage points, in the FM group; there was no change in the NFM group. Hemoglobin (coefficient = 0.22, P < 0.01) was positively and TfR (coefficient = -0.29, P < 0.001) negatively associated with treatment, controlling for their respective baseline values, age, and gender. Treatment with FM was negatively associated with the likelihood of being anemic (pseudo R(2) = 0.085, P < 0.03) after 6 mo of intervention. Ferrous gluconate added to whole cow's milk as a fortificant along with ascorbic acid is efficacious in reducing the prevalence of anemia and in improving iron status of Mexican toddlers. The results of this study lead to broadening a subsidized FM distribution program to 4.2 million beneficiary children 1-11 y of age in Mexico.

Weekly iron as a safe alternative to daily supplementation for nonanemic pregnant women

BACKGROUND

We undertook this study to compare the effectiveness and safety of antenatal daily and weekly supplementation with iron, folic acid, and vitamin B(12) in healthy, pregnant women who were not anemic at gestational week 20.

METHODS

Women with singleton pregnancies and blood hemoglobin (Hb) >115 g/L at gestational week 20 (equivalent to 105 g/L at sea level) were randomly assigned to two groups, one consuming one tablet containing 60 mg iron, 200 mug folic acid and 1 mug vitamin B(12) daily (DS, n = 56); the other consuming two tablets once weekly (WS, n = 60). Blood Hb and serum ferritin concentrations were measured every 4 weeks from weeks 20 to 36, and pregnancy outcomes were evaluated.

RESULTS

Mild anemia and hypoferritinemia throughout pregnancy occurred less frequently in DS than WS. None of the 116 women had Hb concentrations <103 g/L at any evaluation point. In contrast, hemoconcentration (Hb >145 g/L) from gestational week 28 onwards occurred in 11% in DS and 2% in WS. We observed ex post facto that hemoconcentration at gestational week 28 was associated with a significantly higher relative risk of low birth weight (RR 6.23, 95% CI 1.46-26.57) and premature delivery (RR 7.78, 95% CI 1.45-24.74).

CONCLUSIONS

In women who were nonanemic at gestational week 20, both schemes (DS and WS) prevented the occurrence of Hb levels <100 g/L. DS women had a higher incidence of hemoconcentration. Hemoconcentration was associated with increased risk of low birth weight and premature delivery.

Nutritional status of indigenous children at boarding schools in northern Mexico

OBJECTIVE

To assess the nutritional status of Tarahumara children at indigenous boarding schools.

DESIGN

Cross-sectional comprehensive nutritional survey.

SETTING

The schools sampled were located in indigenous municipalities of the northern Mexican state of Chihuahua.

SUBJECTS

The study was carried out in 2001 among 331 children aged 6-14 y from a sample of five schools. Anthropometric measurements, a thyroid exam and capillary haemoglobin levels were obtained from the children. Serum concentrations of ferritin, iron, total iron-binding capacity, vitamin B(12), folic acid and zinc were collected from a subsample of 100 children.

RESULTS

The prevalence of wasting and overweight (children 6-9 y) was 1.1 and 4.6%, respectively, and of underweight, risk of overweight and overweight (10-14 y) was 3.2, 5.1 and 0.6%, respectively. Stunting (6-12 y) was present in 22.3% of the children. The total goitre rate was 5.4%. The prevalence of anaemia was 13% (boys 11.4, girls 14.5%). Overall, 24.2% of the children were iron deficient (depletion 11.1%, deficient erythropoiesis 3%, iron deficiency anaemia 10.1%). No child had folic acid values <3 ng/ml, but 20.2% had low (<200 microg/dl) and 27.3% marginal (200-300 microg/dl) vitamin B(12) levels, and 80.2% had low zinc concentrations (<60 microg/dl).

CONCLUSIONS

Nutritional underweight and stunting were similar to those reported in rural localities at the national level, but overweight was less prevalent in children aged 10-14 y. Various micronutrient deficiencies was identified including zinc and vitamin B(12), but the prevalence of iron and folic acid deficiency was lower than expected. These results suggest that Tarahumara children attending boarding schools may be the better-off children from these extremely poor and marginalized areas.

SPONSORSHIP

Swedish Agency for Research Cooperation with Developing Countries and the Mexican Social Security Institute.