A lack of information on the etiology of anemia has hampered the design and monitoring of anemia-control efforts.
We aimed to evaluate predictors of anemia in preschool children (PSC) (age range: ...6–59 mo) by country and infection-burden category.
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.
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.
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.
Maternal Height and Child Growth Patterns Addo, O. Yaw, PhD; Stein, Aryeh D., PhD; Fall, Caroline H., DM ...
The Journal of pediatrics,
08/2013, Volume:
163, Issue:
2
Journal Article
Peer reviewed
Open access
Objective To examine associations between maternal height and child growth during 4 developmental periods: intrauterine, birth to age 2 years, age 2 years to mid-childhood (MC), and MC to adulthood. ...Study design Pooled analysis of maternal height and offspring growth using 7630 mother–child pairs from 5 birth cohorts (Brazil, Guatemala, India, the Philippines, and South Africa). We used conditional height measures that control for collinearity in height across periods. We estimated associations between maternal height and offspring growth using multivariate regression models adjusted for household income, child sex, birth order, and study site. Results Maternal height was associated with birth weight and with both height and conditional height at each age examined. The strongest associations with conditional heights were for adulthood and 2 years of age. A 1-cm increase in maternal height predicted a 0.024 (95% CI: 0.021-0.028) SD increase in offspring birth weight, a 0.037 (95% CI: 0.033-0.040) SD increase in conditional height at 2 years, a 0.025 (95% CI: 0.021-0.029 SD increase in conditional height in MC, and a 0.044 (95% CI: 0.040-0.048) SD increase in conditional height in adulthood. Short mothers (<150.1 cm) were more likely to have a child who was stunted at 2 years (prevalence ratio = 3.20 (95% CI: 2.80-3.60) and as an adult (prevalence ratio = 4.74, (95% CI: 4.13-5.44). There was no evidence of heterogeneity by site or sex. Conclusion Maternal height influences offspring linear growth over the growing period. These influences likely include genetic and non-genetic factors, including nutrition-related intergenerational influences on growth that prevent the attainment of genetic height potential in low- and middle-income countries.
Background The Child Health and Mortality Prevention Surveillance Network (CHAMPS) identifies causes of under-5 mortality in high mortality countries. Objective To address challenges in postmortem ...nutritional assessment, we evaluated the impact of anthropometry training and the feasibility of 3D imaging on data quality within the CHAMPS Kenya site. Design Staff were trained using World Health Organization (WHO)-recommended manual anthropometry equipment and novel 3D imaging methods to collect postmortem measurements. Following training, 76 deceased children were measured in duplicate and were compared to measurements of 75 pre-training deceased children. Outcomes included measures of data quality (standard deviations of anthropometric indices and digit preference scores (DPS)), precision (absolute and relative technical errors of measurement, TEMs or rTEMs), and accuracy (Bland-Altman plots). WHO growth standards were used to produce anthropometric indices. Post-training surveys and in-depth interviews collected qualitative feedback on measurer experience with performing manual anthropometry and ease of using 3D imaging software. Results Manual anthropometry data quality improved after training, as indicated by DPS. Standard deviations of anthropometric indices exceeded limits for high data quality when using the WHO growth standards. Reliability of measurements post-training was high as indicated by rTEMs below 1.5%. 3D imaging was highly correlated with manual measurements; however, on average 3D scans overestimated length and head circumference by 1.61 cm and 2.27 cm, respectively. Site staff preferred manual anthropometry to 3D imaging, as the imaging technology required adequate lighting and additional considerations when performing the measurements. Conclusions Manual anthropometry was feasible and reliable postmortem in the presence of rigor mortis. 3D imaging may be an accurate alternative to manual anthropometry, but technology adjustments are needed to ensure accuracy and usability.
Midupper arm circumference (MUAC) has long been used in anthropometric assessments of nutritional status in field settings, especially in emergency situations, but percentile ranges for healthy, ...well-nourished children are currently unavailable.
We developed reference curves for MUAC and derived measures of arm muscle area (AMA) and arm fat area (AFA) on the basis of the population used in the current CDC body mass index growth charts.
We analyzed cross-sectional MUAC and triceps (triceps skinfold thickness) data from 32,952 US children aged 1-20 y. Generalized additive models for location, scale, and shape were used to calculate semiparametric smoothed percentiles and L, M, and S coefficients needed for z-score estimation by age and sex. Equations were developed with the use of the height-for-age z score (HAZ) to adjust for the associations of stature with upper arm measures.
MUAC increased with age steadily throughout the growing period. For children <5 y old, lower percentile ranges varied markedly across age and sex such that the single cutoff (<11.5 or 12.5 cm) for field screening of acute malnutrition did not track along the same percentile. AFA and AMA growth patterns exhibited sex-specific trends including multiple distinct age-related inflections that were more pronounced in males for AFA-for-age than in females. HAZ and age were substantially and independently related with all arm measures.
The new reference percentile ranges for midupper arm measures for healthy children provide a useful nutritional assessment tool in a wide variety of settings. Height status (HAZ) has complex independent associations with arm measures irrespective of the distributional ranking by age and sex. Prediction equations that account for these effects further extend the practical use of the new curves.
Growing evidence supports the role of preconception maternal nutritional status (PMNS) on birth outcomes; however, evidence of relationships with child growth are limited. We examined associations ...between PMNS (height, weight and body mass index- BMI) and offspring growth during the first 1000 days. We used prospective cohort data from a randomized-controlled trial of preconception micronutrient supplementation in Vietnam, PRECONCEPT (n = 1409). Poisson regression models were used to examine associations between PMNS and risk of offspring stunting (<-2 HAZ) at 2 years. We used path analytic models to examine associations with PMNS on fetal growth (ultrasound measurements) and offspring HAZ at birth and 2 years. All models were adjusted for child age, sex, gestational weight gain, education, socioeconomic status and treatment group. A third of women had a preconception height < 150cm or weight < 43 kg. Women with preconception height < 150 cm or a weight < 43 kg were at increased risk of having a stunted child at 2 years (incident risk ratio IRR: 1.85, 95% CI 1.51-2.28; IRR 1.35, 95% CI 1.10-1.65, respectively). While the traditional low BMI cut-off (< 18.5 kg/m2) was not significant, lower BMI cut-offs (< 17.5 kg/m2 or < 18.0 kg/m2) were significantly associated with 1.3 times increased risk of child stunting. In path models, PMNS were positively associated with fetal growth (ultrasound measurements) and offspring HAZ at birth and 2 years. For each 1 standard deviation (SD) increase in maternal height and weight, offspring HAZ at 2 years increased by 0.30 SD and 0.23 SD, respectively. In conclusion, PMNS influences both offspring linear growth and risk of stunting across the first 1000 days. These findings underscore the importance of expanding the scope of current policies and strategies to include the preconception period in order to reduce child stunting.
Serum ferritin concentrations are the most widely used indicator for iron deficiency. WHO determined that insufficient data are available to revise the serum ferritin thresholds of less than 12 μg/L ...for children and less than 15 μg/L for women, which were developed on the basis of expert opinion, to define iron deficiency. We aimed to derive new physiologically based serum ferritin concentration thresholds for iron deficiency in healthy young children and non-pregnant women using data from the US National Health and Nutrition Examination Survey (NHANES).
In this serial cross-sectional study, we examined the relationship of serum ferritin with two independent indicators of iron-deficient erythropoiesis, haemoglobin and soluble transferrin receptor (sTfR), in children (12-59 months) and non-pregnant women (15-49 years) using cross-sectional NHANES data from 2003-06, 2007-10, and 2015-18. NHANES is a US national stratified multistage probability sample that includes a household interview followed by a standardised physical examination in a mobile examination centre. We excluded individuals with missing serum ferritin, sTfR, haemoglobin, or white blood cell counts measurements; non-pregnant women with missing C-reactive protein (CRP), alanine aminotransferase (ALT) or aspartate aminotransferase (AST) data were also excluded. In addition, individuals with infection (white blood cell counts >10·0×10
/L) and non-pregnant women with possible liver disease (ALT >70 IU/L or AST >70 IU/L) and inflammation (CRP >5·0 mg/L) were excluded. We examined distributions of haemoglobin and sTfR with serum ferritin and used restricted cubic spline regression models to determine serum ferritin thresholds for iron-deficient erythropoiesis.
5964 children and 10 462 non-pregnant women had physical examinations and were screened for inclusion in the study, of whom 2569 (43·1%) children and 7498 (71·7%) non-pregnant women were included. At lower serum ferritin concentrations, median haemoglobin concentration decreased as sTfR concentration increased, with each varying in a curvilinear manner. Using restricted cubic spline plateau points to determine the onset of iron-deficient erythropoiesis, the serum ferritin thresholds identified by haemoglobin and sTfR concentrations were not different. For children, the haemoglobin identified serum ferritin threshold was 19·9 μg/L (95% CI 18·8-22·6) and the sTfR identified serum ferritin threshold was 20·0 μg/L (19·4-20·9; p=0·89). For women the haemoglobin identified serum ferritin threshold was 25·2 μg/L (24·2-26·2) and the sTfR identified serum ferritin threshold was 24·0 μg/L (23·3-24·6; p=0·05).
The association between two independent indicators of iron-deficient erythropoiesis, haemoglobin and sTfR, identified serum ferritin concentration thresholds of about 20 μg/L for children and 25 μg/L for non-pregnant women, providing physiological evidence of potential new thresholds for consideration when determining the prevalence and distribution of iron deficiency in populations. In healthy children and non-pregnant women, physiologically based thresholds for iron deficiency might be more clinically and epidemiologically relevant than those based on expert opinion. Validation of this physiologically based approach in non-US populations might help the international harmonisation of serum ferritin thresholds for iron deficiency.
None.
Background: Food fortification is one approach for addressing anemia, but information on program effectiveness is limited.Objective: We evaluated the impact of Costa Rica's fortification program on ...anemia in women aged 15–45 y and children aged 1–7 y.Design: Reduced iron, an ineffective fortificant, was replaced by ferrous fumarate in wheat flour in 2002, and ferrous bisglycinate was added to maize flour in 1999 and to liquid and powdered milk in 2001. We used a one-group pretest-posttest design and national survey data from 1996 (baseline; 910 women, 965 children) and 2008–2009 (endline; 863 women, 403 children) to assess changes in iron deficiency (children only) and anemia. Data were also available for sentinel sites (1 urban, 1 rural) for 1999–2000 (405 women, 404 children) and 2008–2009 (474 women, 195 children), including 24-h recall data in children. Monitoring of fortification levels was routine.Results: Foods were fortified as mandated. Fortification provided about one-half the estimated average requirement for iron in children, mostly and equally through wheat flour and milk. Anemia was reduced in children and women in national and sentinel site comparisons. At the national level, anemia declined in children from 19.3% (95% CI: 16.8%, 21.8%) to 4.0% (95% CI: 2.1%, 5.9%) and in women from 18.4% (95% CI: 15.8%, 20.9%) to 10.2% (95% CI: 8.2%, 12.2%). In children, iron deficiency declined from 26.9% (95% CI: 21.1%, 32.7%) to 6.8% (95% CI: 4.2%, 9.3%), and iron deficiency anemia, which was 6.2% (95% CI: 3.0%, 9.3%) at baseline, could no longer be detected at the endline.Conclusions: A plausible impact pathway suggests that fortification improved iron status and reduced anemia. Although unlikely in the Costa Rican context, other explanations cannot be excluded in a pre/post comparison.
The correct interpretation of hemoglobin (Hb) to identify anemia requires adjusting for altitude and smoking. Current adjustments were derived using data collected before 1985, from low‐income ...preschool‐aged children (PSC) in the United States and indigenous men in Peru for altitude, and from White women of reproductive age (WRA) in the United States for smoking. Given the oldness and limited representativeness of these data, we reexamined associations between Hb and altitude and/or smoking using 13 population‐based surveys and 1 cohort study each conducted after 2000. All WHO regions except South‐East Asia were represented. The dataset included 68,193 observations among PSC (6−59 months) and nonpregnant WRA (15−49 years) with data on Hb and altitude (−28 to 4000 m), and 19,826 observations among WRA with data on Hb and smoking (status or daily cigarette quantity). Generalized linear models were used to assess the robustness of associations under varying conditions, including controlling for inflammation‐corrected iron and vitamin A deficiency. Our study confirms that Hb should be adjusted for altitude and/or smoking; these adjustments are additive. However, recommendations for Hb adjustment likely need updating. Notably, current recommendations may underadjust Hb for light smokers and for those residing at lower altitudes and overadjust Hb for those residing at higher altitudes.
In 2001, the WHO established hemoglobin (Hb) concentration cutoffs to define anemia that included adjustments to account for altitude and smoking. Given the oldness and limited representativeness (i.e., geographic, age, and race) of the data used to establish the adjustments, our objective was to examine the association between Hb and altitude and/or smoking among diverse population groups using more recent (since 2000), multinational data in an effort to evaluate current WHO recommendations for adjusting Hb for altitude and smoking.
BACKGROUND: Skinfold thicknesses have long been considered important and valid measurements of subcutaneous fat. Nevertheless, there are no current skinfold reference data for US children and ...adolescents. OBJECTIVE: We developed new percentile reference curves for triceps and subscapular skinfold thicknesses by using the same national samples as those included in the reference curves for body mass index (BMI) in the Centers for Disease Control and Prevention 2000 Growth Charts. DESIGN: We included triceps and subscapular skinfold-thickness measurements for 32,783 individuals who also had complete data for BMI. The LMS method was used to derive 10 smoothed skinfold-thickness percentile reference curves and to generate the L, M, and S parameters that allow the calculation of standardized z scores. RESULTS: The new reference curves exhibit established age- and sex-related patterns of development, including dramatic prepubescent increases in subcutaneous fatness in boys at the highest percentiles. Comparisons of smoothed medians for race-ethnicity groups confirm greater subcutaneous fatness in white children than in black age mates at the triceps site but similar median subscapular skinfold thicknesses. Median skinfold thicknesses for children considered overweight (≥85th percentile) or obese (≥95th percentile) on the basis of BMI cutoffs do not follow closely the skinfold percentile reference channels across age, especially in boys, which suggests a certain degree of independence between BMI and skinfold thickness at the upper extremes of the BMI distribution. CONCLUSIONS: The age- and sex-standardized skinfold percentiles and z scores will be appropriate for a wide range of research applications that consider measures of subcutaneous fat. Because they were developed by using the same children as those used for the 2000 BMI curves of the Centers for Disease Control and Prevention, they provide an important new complementary assessment tool that should be appropriate for almost all US children and adolescents.
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