Vitamin A deficiency and determinants of vitamin A status in Bangladeshi children and women: findings of a national survey.

OBJECTIVE: Using data from the national micronutrients survey 2011-2012, the present study explored the status of subclinical vitamin A nutrition and the underlying determinants in the Bangladeshi population. DESIGN: A nationwide cross-sectional study. Settings The survey covered 150 clusters; fifty in each of rural, urban and slum strata. SUBJECTS: Three population groups: (i) pre-school age children (6-59 months; PSAC); (ii) school age children (6-14 years; SAC); and (iii) non-pregnant non-lactating women (15-49 years; NPNLW). RESULTS: National prevalence of subclinical vitamin A deficiency was 20·5, 20·8 and 5·3 % in PSAC, SAC and NPNLW, respectively. Slum populations had higher prevalence compared with urban (PSAC: 38·1 v. 21·2 %, P0·05 for differences in ß between <3 months v. 3-6 months, 6-9 months and 9-12 months). CONCLUSIONS: Prevalence of subclinical vitamin A deficiency was high in children in Bangladesh. Intakes of animal-source foods and leafy vegetables were associated with higher and lower retinol status, respectively. Increased food diversity through animal-source foods is required.

Prevalence and risk factors of vitamin D insufficiency and deficiency among 6-24-month-old underweight and normal-weight children living in an urban slum of Bangladesh.

OBJECTIVE: We quantified the prevalence of vitamin D status in 6-24-month-old underweight and normal-weight children and identified the socio-economic and dietary predictors for status. DESIGN: Cross-sectional, baseline data from a nutritional intervention study were analysed. Multinomial logistic regression was used to estimate the odds of being vitamin D deficient or insufficient with the reference being vitamin D sufficient. SETTING: Urban slum area of Mirpur field site, Dhaka, Bangladesh. SUBJECTS: Underweight (weight-for-age Z-score <-2·00) and normal-weight (weight-for-age Z-score ≥-1·00) children aged 6-24 months. RESULTS: Among 468 underweight children, 23·1 % were sufficient, 42·3 % insufficient, 31·2 % deficient and 3·4 % severely vitamin D deficient. Among 445 normal-weight children, 14·8 % were sufficient, 39·6 % insufficient and 40·0 % deficient and 5·6 % severely deficient. With adjusted multinominal regression analysis, risk factors (OR (95 % CI)) for vitamin D deficiency in underweight children were: older age group (18-24 months old; 2·9 (1·5-5·7)); measurement of vitamin D status during winter (3·0 (1·4-6·4)) and spring (6·9 (3·0-16·1)); and maternal education (≥6 years of institutional education; 2·2 (1·0-4·9)). In normal-weight children, older age group (3·6 (1·2-10·6)) and living in the richest quintile (3·7 (1·1-12·5)) were found to be significantly associated with vitamin D insufficiency. CONCLUSIONS: The study demonstrates a significant burden of vitamin D insufficiency and deficiency in both underweight and normal-weight children <2 years of age from an urban slum of Bangladesh. Identification of risk factors may help in mitigating the important burden in such children.

Determinants of iron status and Hb in the Bangladesh population: the role of groundwater iron.

OBJECTIVE: Using data from the national micronutrients survey 2011-2012, the present study explored the determinants of Fe status and Hb levels in Bangladesh with a particular focus on groundwater Fe. DESIGN: Cross-sectional study conducted at the nationwide scale. Settings The survey was conducted in 150 clusters, fifty in each of the three strata of rural, urban and slum. SUBJECTS: Three population groups: pre-school age children (6-59 months; PSAC), school age children (6-14 years; SAC) and non-pregnant non-lactating women (15-49 years; NPNLW). RESULTS: National prevalence of Fe deficiency was 10·7 %, 7·1 % and 3·9-9·5 % in PSAC, NPNLW and SAC, respectively. Prevalence of anaemia was 33·1 % (PSAC), 26·0 % (NPNLW) and 17·1-19·1 % (SAC). Multivariate regression analyses showed that the area with 'predominantly high groundwater Fe' was a determinant of higher serum ferritin levels in NPNLW (standardized ß=0·19; P=0·03), SAC (standardized ß=0·22; P=0·01) and PSAC (standardized ß=0·20; P=0·03). This area also determined higher levels of Hb in PSAC (standardized ß=0·14; P=0·01). CONCLUSIONS: National prevalence of Fe deficiency in Bangladesh is low, contrary to the widely held assumption. High Fe level in groundwater is associated with higher Fe status (all populations) and higher Hb level (PSAC).

The MAL-ED cohort study in Mirpur, Bangladesh.

The Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) study site in Bangladesh is located in the capital city of Dhaka in an urban slum that has one of the highest population densities in the world. The site is in the Bauniabadh area of Mirpur, Dhaka. A typical squatter settlement, the average family size of households in Mirpur Bauniabadh is 4.5, with 48% females. About 20% of households have a monthly income of only US$62. About 30% of mothers never attended school, and only 3% obtained secondary school education. The majority of the people are day laborers, garment workers, and transport workers. About 72% of caregivers always wash their hands after helping the child defecate and 6.6% never wash their hands. The diarrheal attack rate for Mirpur is 4.69 episodes per child per year. The study site is representative of a typical urban slum of Dhaka city in terms of demographics, socioeconomic status, and general health indicators.

Measuring socioeconomic status in multicountry studies: results from the eight-country MAL-ED study.

BACKGROUND: There is no standardized approach to comparing socioeconomic status (SES) across multiple sites in epidemiological studies. This is particularly problematic when cross-country comparisons are of interest. We sought to develop a simple measure of SES that would perform well across diverse, resource-limited settings. METHODS: A cross-sectional study was conducted with 800 children aged 24 to 60 months across eight resource-limited settings. Parents were asked to respond to a household SES questionnaire, and the height of each child was measured. A statistical analysis was done in two phases. First, the best approach for selecting and weighting household assets as a proxy for wealth was identified. We compared four approaches to measuring wealth: maternal education, principal components analysis, Multidimensional Poverty Index, and a novel variable selection approach based on the use of random forests. Second, the selected wealth measure was combined with other relevant variables to form a more complete measure of household SES. We used child height-for-age Z-score (HAZ) as the outcome of interest. RESULTS: Mean age of study children was 41 months, 52% were boys, and 42% were stunted. Using cross-validation, we found that random forests yielded the lowest prediction error when selecting assets as a measure of household wealth. The final SES index included access to improved water and sanitation, eight selected assets, maternal education, and household income (the WAMI index). A 25% difference in the WAMI index was positively associated with a difference of 0.38 standard deviations in HAZ (95% CI 0.22 to 0.55). CONCLUSIONS: Statistical learning methods such as random forests provide an alternative to principal components analysis in the development of SES scores. Results from this multicountry study demonstrate the validity of a simplified SES index. With further validation, this simplified index may provide a standard approach for SES adjustment across resource-limited settings.

Association between enteropathogens and malnutrition in children aged 6-23 mo in Bangladesh: a case-control study.

Background: Early exposure to enteropathogens has been associated with malnutrition in children in low-resource settings. However, the contribution of individual enteropathogens remains poorly defined. Molecular diagnostics offer an increase in sensitivity for detecting enteropathogens but have not been comprehensively applied to studies of malnutrition.Objective: We sought to identify enteropathogens associated with malnutrition in Bangladesh.Design: Malnourished children [weight-for-age z score (WAZ) <-2] aged 6-23 mo in Dhaka, Bangladesh, and identified by active community surveillance were enrolled as cases, and normal-weight children (WAZ >-1) of the same age and from the same community were enrolled as controls. Stools were collected at enrollment and, for cases, after a 5-mo nutritional intervention. Enrollment and follow-up stools were tested by quantitative polymerase chain reaction for 32 enteropathogens with the use of a custom-developed TaqMan Array Card.Results: Enteropathogen testing was performed on 486 cases and 442 controls upon enrollment and 365 cases at follow-up. At enrollment, the detection of enteroaggregative Escherichia coli (OR: 1.39; 95% CI: 1.05, 1.83), Campylobacter spp. (OR: 1.46; 95% CI: 1.11, 1.91), heat-labile enterotoxin-producing E. coli (OR: 1.55; 95% CI: 1.04, 2.33), Shigella/enteroinvasive E. coli (OR: 1.65; 95% CI: 1.10, 2.46), norovirus genogroup I (OR: 1.66; 95% CI: 1.23, 2.25), and Giardia (OR: 1.73; 95% CI: 1.20, 2.49) were associated with malnourished cases, and the total burden of these pathogens remained associated with malnutrition after adjusting for sociodemographic factors. The number of these pathogens at follow-up was negatively associated with the change in WAZ during the intervention (-0.10 change in WAZ per pathogen detected; 95% CI: -0.14, -0.06), whereas the number at enrollment was positively associated with the change in WAZ (0.05 change in WAZ per pathogen detected; 95% CI: 0.00, 0.10).Conclusions: A subset of enteropathogens was associated with malnutrition in this setting. Broad interventions designed to reduce the burden of infection with these pathogens are needed. This trial was registered at clinicaltrials.gov as NCT02441426.

Undernutrition, Vitamin A and Iron Deficiency Are Associated with Impaired Intestinal Mucosal Permeability in Young Bangladeshi Children Assessed by Lactulose/Mannitol Test.

BACKGROUND: Lactulose/mannitol (L:M) test has been used as a non-invasive marker of intestinal mucosal -integrity and -permeability (enteropathy). We investigated the association of enteropathy with anthropometrics, micronutrient- status, and morbidity in children. METHODS: The urine and blood samples were collected from 925 children aged 6-24 months residing in Mirpur slum of Dhaka, Bangladesh during November 2009 to April 2013. L:M test and micronutrient status were assessed in the laboratory of International Centre for Diarrhoeal Diseases Research, Bangladesh (icddr,b) following standard procedure. RESULTS: Mean±SD age of the children was 13.2±5.2 months and 47.8% were female. Urinary- lactulose recovery was 0.264±0.236, mannitol recovery was 3.423±3.952, and L:M was 0.109±0.158. An overall negative correlation (Spearman's-rho) of L:M was found with age (rs = -0.087; p = 0.004), weight-for-age (rs = -0.077; p = 0.010), weight-for-length (rs = -0.060; p = 0.034), mid-upper-arm-circumference (rs = -0.098; p = 0.001) and plasma-retinol (rs = -0.105; p = 0.002); and a positive correlation with plasma α-1-acid glycoprotein (rs = 0.066; p = 0.027). However, most of the correlations were not very strong. Approximately 44% of children had enteropathy as reflected by L:M of ≥0.09. Logistic regression analysis revealed that younger age (infancy) (adjusted odds ratio (AOR) = 1.35; p = 0.027), diarrhea (AOR = 4.00; p = 0.039) or fever (AOR = 2.18; p = 0.003) within previous three days of L:M test were the risk factors of enteropathy (L:M of ≥0.09). CONCLUSIONS: Enteropathy (high L:M) is associated with younger age, undernutrition, low vitamin A and iron status, and infection particularly diarrhea and fever.

Extent of vitamin A deficiency among rural pregnant women in Bangladesh.

OBJECTIVE: To investigate the prevalence of vitamin A deficiency (VAD) among pregnant women in rural Bangladesh, and examine the relationship between various factors and vitamin A status. SETTING: Community Nutrition Promoter (CNP) centres in Kapasia sub-district of Gazipur district, Bangladesh. DESIGN: A cross-sectional study. SUBJECTS AND METHODS: Two hundred women, aged 18-39 years, in their second or third trimester of pregnancy were selected from seventeen CNP centres in four unions of Kapasia sub-district where they usually visit for antenatal care. Various socio-economic, personal and pregnancy-related information, dietary intake of vitamin A and mid-upper arm circumference (MUAC) data were collected. Serum retinol (vitamin A) concentration was determined. RESULTS: More than half (51 %) of the pregnant women had low vitamin A status (serum retinol <1.05 micromol/l) with 18.5 % having VAD (serum retinol <0.70 micromol/l). Fifty-three per cent of the women's vitamin A intake was less than the recommended dietary allowance. By multiple regression analysis, MUAC, per-capita expenditure on food and wealth index were found to have significant independent positive relationship with serum retinol concentration, while gestational age of the pregnant women had a negative relationship. The overall F-ratio (10.3) was highly significant (P = 0.0001), the adjusted R2 was 0.18 (multiple R = 0.45). CONCLUSION: VAD is highly prevalent among rural pregnant women in Bangladesh. Gestational age, nutritional status, per-capita expenditure on food and wealth index appear to be important in influencing the vitamin A status of these women. An appropriate intervention is warranted in order to improve the vitamin A status.