The comparison of mixed distribution analysis with a three-criteria model as a method for estimating the prevalence of iron deficiency anaemia in Costa Rican children aged 12-23 months

The prevalence of anemia and iron deficiency is more common in breastfed infants than their mothers in Bhaktapur, Nepal

Background/Objectives:

Iron deficiency anemia is a widespread public health problem, particularly in low- and middle-income countries. Maternal iron status around and during pregnancy may influence infant iron status. We examined multiple biomarkers to determine the prevalence of iron deficiency and anemia among breastfed infants and explored its relationship with maternal and infant characteristics in Bhaktapur, Nepal.

Subjects/Methods:

In a cross-sectional survey, we randomly selected 500 mother–infant pairs from Bhaktapur municipality. Blood was analyzed for hemoglobin, ferritin, total iron-binding capacity, transferrin receptors and C-reactive protein.

Results:

The altitude-adjusted prevalence of anemia was 49% among infants 2–6-month-old (hemaglobin (Hb) <10.8 g/dl) and 72% among infants 7–12-month-old (Hb <11.3 g/dl). Iron deficiency anemia, defined as anemia and serum ferritin <20 or <12 μg/l, affected 9 and 26% of infants of these same age groups. Twenty percent of mothers had anemia (Hb <12.3 g/dl), but only one-fifth was explained by depletion of iron stores. Significant predictors of infant iron status and anemia were infant age, sex and duration of exclusive breastfeeding and maternal ferritin concentrations.

Conclusions:

Our findings suggest that iron supplementation in pregnancy is likely to have resulted in a low prevalence of postpartum anemia. The higher prevalence of anemia and iron deficiency among breastfed infants compared with their mothers suggests calls for intervention targeting newborns and infants.

Prevalence of Iron Deficiency and Anemia among Young Children with Acute Diarrhea in Bhaktapur, Nepal

Iron deficiency anemia is still common in children under five years of age and may impair their growth and cognitive development. Diarrhea is the second most common reason for seeking medical care for young children in Nepal. However, neither screening programs nor effective preventive measures for anemia and iron deficiencies are in place among children with diarrhea in many developing countries. The aims of this study were to determine the prevalence of anemia and iron deficiency and explore their associations with clinical, socioeconomic, and anthropometric parameters in Nepalese children. This was a cross-sectional study based on 1232 children, six to 35 months old, with acute diarrhea participating in a zinc supplementation trial. The mean (SD) hemoglobin was 11.2 g/dL (1.2). Anemia was found in 493 children (40%); this estimate increased to 641 (52%) when we adjusted for the altitude of the study area (hemoglobin <11.3 g/dL). One in every three children had depleted iron stores and 198 (16%) of the children had both depleted iron stores and anemia, indicating iron deficiency anemia. The prevalence of anemia among children presenting with acute diarrhea was high but the degree of severity was mainly mild or moderate. Iron deficiency explained less than half of the total anemia, indicating other nutritional deficiencies inducing anemia might be common in this population.

Efficacy of different iron fortificants in wheat flour in controlling iron deficiency

OBJECTIVE

To observe the different impacts of electrolytic iron, FeSO4, and NaFeEDTA on body iron store of anemic school students.

METHODS

Four hundreds anemic students at the age of 11-18 years were divided into four groups. Of which, three consumed different iron fortificants from wheat flour as food vehicle for six months and one consumed non-fortified flour (control). The fortification level of electrolytic iron, FeSO4, and NaFeEDTA was 60 mg Fe/kg, 30 mg Fe/kg, and 20 mg Fe/kg, respectively. Blood samples were collected at 0, 2, 4, and 6 months and hemoglobin (Hb), serum ferritin (SF), and transferrin receptor (TfR) were measured.

RESULTS

The hemoglobin levels in three intervention groups increased, the increments of Hb in the NaFeEDTA group were significantly higher than that in the other groups. SF and TfR levels increased in the tested groups and body iron store in the NaFeEDTA group was higher than that in the other groups. These parameters did not show any significant changes in the control group.

CONCLUSION

NaFeEDTA and FeSO4 fortified wheat flour has positive impacts on iron status in anemic students and NaFeEDTA is more effective than FeSO4, while electrolytic iron is less effective in improving iron store in anemic students.

Fatores determinantes dos níveis de hemoglobina em crianças aos 12 meses de vida na Zona da Mata Meridional de Pernambuco

OBJETIVOS: avaliar os fatores determinantes dos níveis de hemoglobina de crianças aos 12 meses de vida, em quatro municípios da Zona da Mata Meridional de Pernambuco. MÉTODOS: estudo transversal, realizado em uma sub-amostra de 245 lactentes, pertencentes a uma coorte de 652 crianças. A coleta de dados foi realizada no período de janeiro a agosto de 1999. RESULTADOS: a prevalência de anemia foi de 73,2%, sendo a média de hemoglobina de 9,8 g/dL (DP = 1,6 g/dL). A análise de variância apresentou uma associação estatisticamente significante entre níveis de hemoglobina e escolaridade materna, posse de televisão no domicílio, peso ao nascer, duração do aleitamento materno exclusivo, ocorrência de diarréia e estado nutricional segundo os índices peso/idade e comprimento/idade. A análise de regressão linear múltipla mostrou que as condições socioeconômicas, o peso ao nascer, a duração do aleitamento materno exclusivo e a ocorrência de diarréia tiveram um impacto significante na variação dos níveis de hemoglobina. CONCLUSÕES: os resultados confirmam ser a anemia um relevante problema de saúde pública, especialmente em lactentes, tendo múltiplos fatores que contribuem para o seu surgimento, sendo necessário, portanto, identificar os mais importantes para serem levados em consideração nos programas de saúde da criança.

The quantitative assessment of body iron

Current initiatives to reduce the high prevalence of nutritional iron deficiency have highlighted the need for reliable epidemiologic methods to assess iron status. The present report describes a method for estimating body iron based on the ratio of the serum transferrin receptor to serum ferritin. Analysis showed a single normal distribution of body iron stores in US men aged 20 to 65 years (mean +/- 1 SD, 9.82 +/- 2.82 mg/kg). A single normal distribution was also observed in pregnant Jamaican women (mean +/- 1 SD, 0.09 +/- 4.48 mg/kg). Distribution analysis in US women aged 20 to 45 years indicated 2 populations; 93% of women had body iron stores averaging 5.5 +/- 3.35 mg/kg (mean +/- 1 SD), whereas the remaining 7% of women had a mean tissue iron deficit of 3.87 +/- 3.23 mg/kg. Calculations of body iron in trials of iron supplementation in Jamaica and iron fortification in Vietnam demonstrated that the method can be used to calculate absorption of the added iron. Quantitative estimates of body iron greatly enhance the evaluation of iron status and the sensitivity of iron intervention trials in populations in which inflammation is uncommon or has been excluded by laboratory screening. The method is useful clinically for monitoring iron status in those who are highly susceptible to iron deficiency.

Mixed distribution analysis identifies saltation and stasis growth

A maximum likelihood method of mixed distribution analysis is investigated for its utility as a method for the identification of saltation and stasis in longitudinal growth data. Daily infant growth data that have been previously identified to follow a saltatory growth process are employed. This is a novel application of the finite mixed distribution analysis (MDA), a method designed to objectively identify the presence of one or more Gaussian populations. The null hypothesis is that a single Gaussian distribution best describes the incremental growth data. This would be compatible with smooth, slowly varying daily growth patterns. This study explores whether or not two distinctive populations are evident in incremental saltatory growth data, as postulated by the saltation and stasis observations. The analysis is important in providing a growth model-independent test for the presence of saltation and stasis by a separate statistical assessment with none of the saltatory algorithm assumptions. The finite mixed distribution analysis identifies that each individual's incremental growth data is statistically best described as a mixture consisting of two components, or two populations of increments (chi-square, p < 0.05). For each individual, one of these populations is centred about a zero increment, and is compatible with the previous evidence of stasis intervals. The second population of data points is characterized by unique distributions for each individual, compatible with the previous observation that infants grow by unique patterns of growth saltations in both amplitude and frequency. The percentage of data points that fall within each of the two unique finite mixture distributions (FMDs) is similar to the proportions of discrete saltation and stasis intervals previously identified by the saltation and stasis method. Thus, the FMD analysis lends support to the nature of growth as a saltatory process characterized by two states in the daily growth of these infants. By contrast with the saltatory algorithm, which is applied to the original serial growth measurements, the mixed distribution analysis employs increments removed from their time relationships. The lack of time series sequence information precludes the mixed distribution method from reconstructing specific temporal patterns of saltatory growth. The present analysis reiterates that individual growth patterns are statistically unique and cannot be reconstructed or identified from group data.