Keith P West

Johns Hopkins University, Baltimore, MD, USA

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Publications (65)522.03 Total impact

  • Article: Low-birthweight rates higher among Bangladeshi neonates measured during active birth surveillance compared to national survey data.
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    ABSTRACT: Birth size is an important gauge of fetal and neonatal health. Birth size measurements were collected within 72 h of life for 16 290 live born, singleton infants in rural Bangladesh from 2004 to 2007. Gestational age was calculated based on the date of last menstrual period. Newborns were classified as small-for-gestational age (SGA) based on a birthweight below the 10th percentile for gestational age, using three sets of US reference data. Birth size distributions were explored based on raw values as well as after z-score standardisation in reference to World Health Organization (WHO) 2006 growth standards. Mean (SD) birthweight (g), length (cm) and head circumference (cm) measurements, completed within [median (25th, 75th percentile)] 15 (8, 23) h of life, were 2433 (425), 46.4 (2.4) and 32.4 (1.6), respectively. Twenty-two per cent were born preterm. Over one-half (55.3%) of infants were born low birthweight; 46.6%, 37.0% and 33.6% had a weight, length and head circumference below -2 z-scores of the WHO growth standard at birth; and 70.9%, 72.2% and 59.8% were SGA for weight based on Alexander et al., Oken et al. and Olsen et al. references, respectively. Infants in this typical rural Bangladesh setting were commonly born small, reflecting a high burden of fetal growth restriction and preterm birth. Our findings, produced by active birth surveillance, suggest that low birthweight is far more common than suggested by cross-sectional survey estimates. Interventions that improve fetal growth during pregnancy may have the largest impact on reducing SGA rates.
    Maternal and Child Nutrition 05/2013; · 1.61 Impact Factor
  • Article: Plasma zinc, vitamin B12 and α-tocopherol are positively and plasma γ-tocopherol is negatively associated with Hb concentration in early pregnancy in north-west Bangladesh.
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    ABSTRACT: OBJECTIVE: The objective of the current analysis was to explore the association of multiple micronutrients with Hb concentration among pregnant women in a South Asian setting, a topic that has not been adequately explored. DESIGN: Sociodemographic, anthropometric and micronutrient status (plasma ferritin, transferrin receptor, retinol, α- and γ-tocopherol, folate, vitamin B12, Zn) and Hb concentration were assessed at early pregnancy. SETTING: The biochemical sub-study was nested within a double-blind, placebo-controlled, community-based vitamin A and β-carotene supplementation trial in rural north-western Bangladesh (JiVitA). All assessments were conducted before trial supplementation was initiated. SUBJECTS: A systematic sample of 285 women was selected from those enrolled in the biochemical sub-study. RESULTS: Seventeen per cent of women were mildly anaemic; moderate and severe anaemia was uncommon (2·1 %). α-Tocopherol, vitamin B12 and Zn deficiencies were common (43·5 %, 19·7 % and 14·7 %, respectively); however, vitamin A, folate and Fe deficiencies were comparatively rare (7·4 %, 2·8 % and <1 %, respectively). Plasma Zn, vitamin B12 and α-tocopherol were positively associated and plasma γ-tocopherol was negatively associated with Hb (P < 0·05) after adjustment for gestational age, inflammation status, season and nutritional status measured by mid-upper arm circumference. CONCLUSIONS: Among pregnant women in rural Bangladesh with minimal Fe deficiency, plasma Zn, vitamin B12, and α- and γ-tocopherol concentrations were associated with Hb concentration. Appreciating the influence on Hb of micronutrients in addition to those with known associations with anaemia, such as Fe, folate, and vitamin A, is important when addressing anaemia in similar settings.
    Public Health Nutrition 03/2013; · 2.17 Impact Factor
  • Article: A cross-sectional study of the prevalence and risk factors for hypertension in rural Nepali women.
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    ABSTRACT: BACKGROUND: The prevalence of hypertension is increasing in much of the South Asian region, including Nepal. This paper reports the prevalence and risk factors of hypertension and pre-hypertension among adult women in a rural community of Nepal. METHODS: Cross-sectional data on socioeconomic status (SES), lifestyle factors and blood pressure (BP) were collected from a cohort of 15,934 women in rural Nepal in 2006--08. Among a subsample (n = 1679), anthropometry and biomarkers of cardiovascular risk were measured. RESULTS: The mean age of women was 34.2 years (range 16.4-71.2 years). More than three percent (3.3%) had hypertension and 14.4% had pre-hypertension. In an adjusted analysis, lower SES, especially lower household farm assets and storage of food for long term consumption, was associated with increased odds of hypertension (OR = 1.14 for mid-level SES and OR = 1.40 for low SES; p for trend < 0.01). Smoking, alcohol use and not working outside the home were also associated with higher risk. In a subsample, both systolic BP (SBP) and diastolic BP (DBP) were positively associated with high triglycerides (SBP beta = 4.1 mm Hg; DBP beta =3.6 mm Hg), high HbA1c (SBP beta = 14.0; DBP beta = 9.2), raised fasting glucose (SBP beta = 10.0; DBP beta = 6.9), high BMI (SBP beta = 6.7; DBP beta = 5.1) and high waist circumference (SBP beta = 6.2; DBP beta = 5.3) after adjusting for potential confounders (p for all <0.01). CONCLUSIONS: Although the prevalence of hypertension was low in this cohort, it was more prevalent among the poorer women and was strongly associated with other cardiovascular risks. These associations at a relatively young age may confer greater risk for cardiovascular disease among women in later life, indicating the need for interventions to reduce the progression from pre-hypertension to hypertension.
    BMC Public Health 01/2013; 13(1):55. · 2.00 Impact Factor
  • Article: Cognitive and motor skills in school-aged children following maternal vitamin A supplementation during pregnancy in rural Nepal: a follow-up of a placebo-controlled, randomised cohort.
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    ABSTRACT: To determine the effects of maternal vitamin A supplementation from preconception through postpartum on cognitive and motor development of children at 10-13 years of age in rural Nepal. Follow-up assessment of children born to women randomly assigned by a village to receive either supplemental vitamin A (7000 µg retinol equivalents) or placebo weekly during a continuous 3.5-year period from 1994-1997. The participants came from 12 wards, a subset of 270 wards in the original trial. Trained staff tested children for cognition by the Universal Nonverbal Intelligence Test (UNIT) and motor ability using four subtests from the Movement Assessment Battery for Children (MABC). Data on schooling, home environment and nutritional and socioeconomic status were also collected. Southern plains district of Sarlahi, Nepal. 390 Nepalese children 10-13 years of age. Raw scores on UNIT and square-root transformed scores on an abridged version of the MABC tests, expressed as cluster-summarised (mean±SD) values to account for the design of the original trial. There were no differences in UNIT (79.61±5.99 vs 80.69±6.71) or MABC (2.64±0.07 vs 2.49±0.09) test scores in children whose mothers were exposed to vitamin A vs placebo (mean differences: -1.07, 95% CI -7.10 to 9.26, p=0.78; 0.15, 95% CI 0.43 to -0.08, p=0.15), respectively. More children in the placebo group had repeated a grade in school (28% of placebo vs 16.7% of vitamin A, p=0.01). Preconceptional to postpartum maternal vitamin A supplementation, in an undernourished setting, does not improve cognition or motor development at ages 10-13 years.
    BMJ open. 01/2013; 3(5).
  • Article: Statistical inference from multiple iTRAQ experiments without using common reference standards.
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    ABSTRACT: Isobaric Tags for Relative and Absolute Quantitation (iTRAQ) is a prominent mass spectrometry technology for protein identification and quantification, capable of analyzing multiple samples in a single experiment. Frequently, iTRAQ experiments are carried out using an aliquot from a pool of all samples, or "masterpool", in one of the channels as a reference sample standard to estimate protein relative abundances in the biological samples and to combine abundance estimates from multiple experiments. In this manuscript we show that using a masterpool is counterproductive. We obtain more precise estimates of protein relative abundance by using the available biological data instead of the masterpool and do not need to occupy a channel that could otherwise be used for another biological sample. In addition, we introduce a simple statistical method to associate proteomic data from multiple iTRAQ experiments with a numeric response and show that this approach is more powerful than the conventionally employed masterpool based approach. We illustrate our methods using data from four replicate iTRAQ experiments on aliquots of the same pool of plasma samples and from a 406 sample project designed to identify plasma proteins that covary with nutrient concentrations in chronically undernourished children from South Asia.
    Journal of Proteome Research 12/2012; · 5.11 Impact Factor
  • Article: Effects of vitamin A and β-carotene supplementation on birth size and length of gestation in rural Bangladesh: a cluster-randomized trial.
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    ABSTRACT: BACKGROUND: Micronutrient deficiencies may be related to poor fetal growth and short gestation. Few studies have investigated the contribution of maternal vitamin A deficiency to these outcomes. OBJECTIVE: In rural northwestern Bangladesh, we examined the effects of weekly antenatal vitamin A and β-carotene supplementation on birth weight, length, circumferential body measures, and length of gestation. DESIGN: With the use of a cluster-randomized, placebo-controlled trial design, pregnant women were enrolled in the first trimester and began receiving their allocated supplements (vitamin A, β-carotene, or placebo) weekly until 3 mo postpartum. Birth anthropometric measures were made at home. RESULTS: Of 13,709 newborns whose birth weight was measured within 72 h of birth, mean (±SD) weight was 2.44 ± 0.42 kg, the prevalence of low birth weight (LBW) was 54.4%, and that of small-for-gestational age (SGA) was 70.5%. Birth weight, length, and chest, head, and arm circumferences did not differ between supplementation and placebo groups nor did rates of LBW and SGA. Mean gestational age at birth was 38.3 ± 2.9 wk, and 25.6% of births occurred before 37 wk. Neither gestational age nor preterm birth rate differed with vitamin A or β-carotene supplementation. CONCLUSIONS: In this rural South Asian population with a high burden of LBW and preterm birth but modest levels of maternal vitamin A deficiency, antenatal vitamin A or β-carotene supplementation did not benefit these birth outcomes. Other nutritional and nonnutritional interventions should be examined to reduce risks of these adverse outcomes in rural South Asia. This trial was registered at clinicaltrials.gov as NCT00198822.
    American Journal of Clinical Nutrition 11/2012; · 6.67 Impact Factor
  • Article: Maternal morbidity in early pregnancy in rural northern Bangladesh.
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    ABSTRACT: OBJECTIVE: To determine the burden of maternal morbidity in early pregnancy in rural northern Bangladesh. METHODS: A cross-sectional analysis was performed on baseline morbidity data from 42 896 pregnant women enrolled in a vitamin A supplementation trial. One-week histories for 31 defined symptoms were collected at 5-12weeks of gestation. Ten illnesses were defined, compatible with ICD-10 diagnoses and WHO definitions. Prevalence, duration, and treatment-seeking behaviors were determined for each symptom and illness. Risk of wasting malnutrition was compared between symptomatic and asymptomatic women. RESULTS: In total, 93.1% of women reported at least 1 symptom. The most frequent symptoms were poor appetite (53.3%), vaginal discharge (48.7%), and nausea (48.1%), each of which lasted 22-27days. The most prevalent illnesses were anemia (36.4%), morning sickness (17.2%), excessive vomiting (7.0%), and reproductive tract infections (6.7%). Symptoms that prompted treatment seeking included jaundice, high-grade fever, and swelling of hands and face. Odds ratios for malnutrition were higher among women with symptoms of anemia (1.30; 95% confidence interval [CI], 1.24-1.36), vaginal discharge (1.37; 95% CI, 1.31-1.43), and high-grade fever (1.23; 95% CI, 1.10-1.37) than among those without symptoms. CONCLUSION: Women in rural Bangladesh report substantial morbidity in the first trimester.
    International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics 10/2012; · 1.41 Impact Factor
  • Article: Maternal Weight and Body Composition during Pregnancy Are Associated with Placental and Birth Weight in Rural Bangladesh.
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    ABSTRACT: Placental growth is a strong predictor of fetal growth, but little is known about maternal predictors of placental growth in malnourished populations. Our objective was to investigate in a prospective study the associations of maternal weight and body composition [total body water (TBW) estimated by bioelectrical impedance and fat and fat-free mass derived from upper arm fat and muscle areas (UAFA, UAMA)] and changes in these with placental and birth weights. Within a cluster-randomized trial of maternal micronutrient supplementation, a subsample of 350 women was measured 3 times across gestation. Longitudinal analysis was used to examine independent associations of ∼10-wk measurements and ∼10-20 wk and ∼20-32 wk changes with birth outcomes. Weight, TBW, and UAMA, but not UAFA, at ∼10 wk were each positively and independently associated with placental weight and birth weight (P < 0.05). Of the maternal ∼10-20 wk changes in measurements, only TBW change and placental weight, and maternal weight and birth weight were positively associated (P < 0.05). Gains in weight, TBW, and UAMA from 20 to 32 wk were positively and UAFA gain was negatively associated with placental weight (P ≤ 0.01). Gains in weight and UAMA from 20 to 32 wk were positively associated with birth weight (P ≤ 0.01). Overall, higher maternal weight and measures of fat-free mass at ∼10 wk gestation and gains from 20 to 32 wk are independently associated with higher placental and birth weight.
    Journal of Nutrition 09/2012; 142(11):2010-6. · 3.92 Impact Factor
  • Article: Hepatitis e, a vaccine-preventable cause of maternal deaths.
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    ABSTRACT: Hepatitis E virus (HEV) is a major cause of illness and of death in the developing world and disproportionate cause of deaths among pregnant women. Although HEV vaccine trials, including trials conducted in populations in southern Asia, have shown candidate vaccines to be effective and well-tolerated, these vaccines have not yet been produced or made available to susceptible populations. Surveillance data collected during 2001-2007 from >110,000 pregnancies in a population of ≈650,000 women in rural Bangladesh suggest that acute hepatitis, most of it likely hepatitis E, is responsible for ≈9.8% of pregnancy-associated deaths. If these numbers are representative of southern Asia, as many as 10,500 maternal deaths each year in this region alone may be attributable to hepatitis E and could be prevented by using existing vaccines.
    Emerging Infectious Diseases 09/2012; 18(9):1401-4. · 6.79 Impact Factor
  • Article: Care-seeking patterns for fatal non-communicable diseases among women of reproductive age in rural northwest Bangladesh.
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    ABSTRACT: Though non-communicable diseases contribute to an increasing share of the disease burden in South Asia, health systems in most rural communities are ill-equipped to deal with chronic illness. This analysis seeks to describe care-seeking behavior among women of reproductive age who died from fatal non-communicable diseases as recorded in northwest rural Bangladesh between 2001 and 2007. This analysis utilized data from a large population-based cohort trial in northwest rural Bangladesh. To conduct verbal autopsies of women who died while under study surveillance, physicians interviewed family members to elicit the biomedical symptoms that the women experienced as well as a narrative of the events leading to deaths. We performed qualitative textual analysis of verbal autopsy narratives for 250 women of reproductive age who died from non-communicable diseases between 2001 and 2007. The majority of women (94%) sought at least one provider for their illnesses. Approximately 71% of women first visited non-certified providers such as village doctors and traditional healers, while 23% first sought care from medically certified providers. After the first point of care, women appeared to switch to medically certified practitioners when treatment from non-certified providers failed to resolve their illness. This study suggests that treatment seeking patterns for non-communicable diseases are affected by many of the sociocultural factors that influence care seeking for pregnancy-related illnesses. Families in northwest rural Bangladesh typically delayed seeking treatment from medically certified providers for NCDs due to the cost of services, distance to facilities, established relationships with non-certified providers, and lack of recognition of the severity of illnesses. Most women did not realize initially that they were suffering from a chronic illness. Since women typically reached medically certified providers in advanced stages of disease, they were usually told that treatment was not possible or were referred to higher-level facilities that they could not afford to visit. Women suffering from non-communicable disease in these rural communities need feasible and practical treatment options. Further research and investment in adequate, appropriate care seeking and referral is needed for women of reproductive age suffering from fatal non-communicable diseases in resource-poor settings.
    BMC Women s Health 08/2012; 12:23.
  • Article: Development of bioelectrical impedance analysis-based equations for estimation of body composition in postpartum rural Bangladeshi women.
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    ABSTRACT: Equations for predicting body composition from bioelectrical impedance analysis (BIA) parameters are age-, sex- and population-specific. Currently there are no equations applicable to women of reproductive age in rural South Asia. Hence, we developed equations for estimating total body water (TBW), fat-free mass (FFM) and fat mass in rural Bangladeshi women using BIA, with 2H2O dilution as the criterion method. Women of reproductive age, participating in a community-based placebo-controlled trial of vitamin A or β-carotene supplementation, were enrolled at 19·7 (sd 9·3) weeks postpartum in a study to measure body composition by 2H2O dilution and impedance at 50 kHz using multi-frequency BIA (n 147), and resistance at 50 kHz using single-frequency BIA (n 82). TBW (kg) by 2H2O dilution was used to derive prediction equations for body composition from BIA measures. The prediction equation was applied to resistance measures obtained at 13 weeks postpartum in a larger population of postpartum women (n 1020). TBW, FFM and fat were 22·6 (sd 2·7), 30·9 (sd 3·7) and 10·2 (sd 3·8) kg by 2H2O dilution. Height2/impedance or height2/resistance and weight provided the best estimate of TBW, with adjusted R2 0·78 and 0·76, and with paired absolute differences in TBW of 0·02 (sd 1·33) and 0·00 (sd 1·28) kg, respectively, between BIA and 2H2O. In the larger sample, values for TBW, FFM and fat were 23·8, 32·5 and 10·3 kg, respectively. BIA can be an important tool for assessing body composition in women of reproductive age in rural South Asia where poor maternal nutrition is common.
    The British journal of nutrition 05/2012; · 3.45 Impact Factor
  • Article: Maternal nutritional status in early pregnancy is associated with body water and plasma volume changes in a pregnancy cohort in rural Bangladesh.
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    ABSTRACT: Plasma volume expansion has been associated with fetal growth. Our objective was to examine the associations between maternal nutritional status in early pregnancy and extracellular water (ECW), total body water (TBW), and percentage plasma volume change across pregnancy. In a subsample of 377 pregnant women participating in a cluster-randomized trial of micronutrient supplementation, hemoglobin, hematocrit, and multi-frequency bioelectrical impedance were measured at ~10, 20, and 32 wk of gestation. In early pregnancy, women were short (mean ± SD, 148.9 ± 5.3 cm) and thin (19.5 ± 2.5 kg/m(2)). In mixed-effects multiple regression models, a 1-unit higher BMI at ~10 wk was associated with higher ECW and TBW (0.27 and 0.66 kg per kg/m(2), respectively; P < 0.01) at ~10, ~20, and ~32 wk. Height was also positively associated with ECW and TBW at each time point. Early pregnancy BMI was negatively associated with gains in ECW and TBW (-0.06 and -0.14 kg per kg/m(2), respectively; P < 0.01) from 10 to 20 wk, but not with 20- to 32-wk gains after accounting for weight gain. BMI was positively associated with percentage changes in plasma volume from 20 to 32 wk (0.57% per kg/m(2); P < 0.05). Height was not associated with changes in body water or plasma volume. Women with low BMI and height in early pregnancy have lower ECW and TBW in early, mid, and late pregnancy and lower late pregnancy plasma volume expansion, potentially increasing risk of fetal growth restriction.
    Journal of Nutrition 04/2012; 142(6):1109-15. · 3.92 Impact Factor
  • Article: The use and interpretation of serum retinol distributions in evaluating the public health impact of vitamin A programmes.
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    ABSTRACT: Developing countries have adopted universal, high-potency vitamin A (VA) supplementation and food fortification as major strategies to control deficiency, prevent nutritional blindness and reduce child mortality. Yet questions persist regarding how best to measure impact and when to phase out supplementation. The present paper provides guidance on the use and interpretation of serum retinol (SROL) distributions as indicators of both programme impact and adequate VA intake in a population. We reviewed extant data on SROL's response to high-potency VA supplementation and VA-fortified foods in children. Supplementation virtually eliminates xerophthalmia and reduces child mortality; however, it shifts the SROL distribution only transiently (<2 months). Regular consumption of VA-fortified foods prevents xerophthalmia, lowers mortality and sustainably improves SROL distributions, from which both compliance and public health impact can be inferred. Given SROL's limited responsiveness to high-potency VA supplementation, target population coverage remains the preferred performance indicator. However, periodic SROL surveys do reflect underlying dietary risk and can guide programming: low or marginal SROL distributions in areas with high supplementation coverage do not signify programme failure, but rather suggest the need to continue supplementation while working to effectively raise dietary VA intakes. We propose that a sustained rise in the SROL distribution, defined as ≤5 % prevalence of SROL < 0·70 μmol/l among vulnerable population groups in at least two consecutive surveys (≥1 year apart), be used as an indicator of stable and adequate dietary VA intake and status in a population, at which point programmes may re-evaluate the need for continued universal supplementation.
    Public Health Nutrition 03/2012; 15(7):1201-15. · 2.17 Impact Factor
  • Article: High prevalence of anemia with lack of iron deficiency among women in rural Bangladesh: a role for thalassemia and iron in groundwater.
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    ABSTRACT: Iron deficiency was absent in a recent population assessment of rural Bangladeshi women exhibiting anemia (57%), suggesting other causes of low hemoglobin. We assessed the relative influence on anemia of thalassemia, groundwater arsenic and iron, and diet among women of reproductive age living in rural Bangladesh. Women (n=207) sampled from a previous antenatal nutrient intervention trial in rural Bangladesh were visited during two seasons in 2008. Collected data included 7-day dietary and 24-hour drinking water intake recalls, 7-day morbidity recall, anthropometry, and drinking water arsenic and iron concentrations. Capillary blood was analyzed for iron (plasma ferritin, soluble transferrin receptor), inflammation (C-reactive protein) and thalassemia (β thalassemia and Hb E) status. In stratified, adjusted analyses, only parity was associated with anemia (odds ratio, OR (95% CI): 11.34 (1.94, 66.15)) for those with thalassemia (28% prevalent). In contrast, groundwater iron intake (>30 mg/d, 0.48 (0.24, 0.96)) and wasting (2.32 (1.17, 4.62)) were associated with anemia among those without thalassemia. Elevated groundwater arsenic (>50 μg/L, 12% of tubewells) and a diverse diet were unrelated to anemia regardless of thalassemia diagnosis (p>0.70 and >0.47, respectively). Among women in this typical rural Bangladeshi area, the prevalence of thalassemia was high and, unlike iron deficiency which was absent most likely due to high iron intake from groundwater, contributed to the risk of anemia. In such settings, the influence of environmental sources of iron and the role of thalassemias in contributing to anemia at the population level may be underappreciated.
    Asia Pacific Journal of Clinical Nutrition 01/2012; 21(3):416-24. · 1.13 Impact Factor
  • Article: Vitamin A supplementation in preschool children and risk of hearing loss as adolescents and young adults in rural Nepal: randomised trial cohort follow-up study.
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    ABSTRACT: To determine whether vitamin A supplementation administered in the preschool years can lower the risk of hearing loss in adolescence and adulthood. Follow-up study of adolescents and young adults who, as preschool aged children in 1989, were enrolled into a cluster randomised, double blinded, placebo controlled trial of vitamin A supplementation. South central, rural Nepal. 2378 adolescents and young adults aged 14 to 23, representing 51% of those who finished the original trial and 71% of those living in the study area in 2006. Every four months for 16 months preschool children were visited at home, given an oral 200,000 IU dose of vitamin A (half dose at age 1-11 months, quarter dose at <1 month) or placebo and the parents were queried about any childhood illnesses in the previous week, including purulent discharge from the ears. Prevalence of mild or worse hearing loss (≥ 30 dB) in the most affected ear and tympanometric measures of middle ear function (peak height, ear canal volume, and gradient). During the original trial, the prevalence of middle ear infection during the preschool years did not differ between the supplement groups. By adolescence and early adulthood, a non-significant 17% reduction in hearing loss occurred among those who had periodically received vitamin A compared with placebo as preschool aged children (odds ratio 0.83, 95% confidence interval 0.62 to 1.12). Among participants with any ear discharge in early childhood, vitamin A supplementation was associated with a reduced risk of hearing loss, by 42% (0.58, 0.37 to 0.92) compared with controls, after adjusting the confidence interval for the design effect of the original trial. Abnormal tympanometric peak height of the middle ear system was less likely among participants supplemented with vitamin A in childhood. In undernourished settings, periodic, high dose vitamin A supplementation may reduce the risk of hearing loss associated with purulent ear infections in early childhood.
    BMJ (Clinical research ed.). 01/2012; 344:d7962.
  • Article: Maternal vitamin A and β-carotene supplementation and risk of bacterial vaginosis: a randomized controlled trial in rural Bangladesh.
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    ABSTRACT: Bacterial vaginosis (BV) in pregnancy is linked to preterm birth, but its risk factors are not well understood. Micronutrient deficiencies may be associated with an increased risk of this condition. We assessed the effect of weekly vitamin A or β-carotene supplementation during pregnancy until 3 mo postpartum on BV risk in rural northeastern Bangladesh. In this cluster-randomized, placebo-controlled trial, 33 clusters (n = 33) were randomly assigned to 3 groups. Women (n = 1812) were examined for BV by using self-administered swabs and the Nugent scoring method in early pregnancy, at 32 wk of gestation, and at 3 mo postpartum. The prevalence of BV in early pregnancy, before supplementation, was 7.6% (95% CI: 6.3%, 9.1%) overall. Neither the prevalence nor the incidence of BV in the third trimester differed by supplement group. However, the prevalence (OR: 0.71; 95% CI: 0.52, 0.98) and incidence (RR: 0.58; 95% CI: 0.41, 0.81) of BV at 3 mo postpartum was lower among women in the vitamin A group (9.1% and 6.7%, respectively) than in the placebo group (12.4% and 11.8%, respectively), but not in the β-carotene group. Both vitamin A and β-carotene reduced the prevalence and incidence of BV at both time points (ie, third trimester and 3 mo postpartum) by 30-40% compared with placebo (all P < 0.05). Weekly vitamin A supplementation reduced the risk of maternal BV in this rural Bangladeshi population. Enhancement of vitamin A status before and during pregnancy may reduce the risk of BV in areas with vitamin A deficiency. This trial is registered at clinicaltrials.gov as NCT00198822.
    American Journal of Clinical Nutrition 11/2011; 94(6):1643-9. · 6.67 Impact Factor
  • Article: Low maternal vitamin B-12 status is associated with offspring insulin resistance regardless of antenatal micronutrient supplementation in rural Nepal.
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    ABSTRACT: Questions have been raised about potentially negative effects of antenatal folic acid use in populations with a high prevalence of vitamin B-12 deficiency. Our objective was to examine the association between maternal folate and vitamin B-12 status in pregnancy on offspring insulin resistance and examine whether the effects of maternal micronutrient supplementation varied by baseline maternal folate and/or vitamin B-12 status. Pregnant women were cluster randomized to receive daily supplements containing vitamin A alone or with folic acid, folic acid+iron, folic acid+iron+zinc, or a multiple micronutrient. In a subsample (n = 1132), micronutrient status biomarkers were analyzed at baseline and late pregnancy. Children born to the women who participated in the trial were visited at 6-8 y of age. Fasting plasma glucose and insulin were used to estimate insulin resistance using the homeostasis model assessment (HOMA-IR). Children whose mothers were deficient in vitamin B-12 (<148 pmol/L, 27%) during early pregnancy had a 26.7% increase in HOMA-IR (P = 0.02), but there was no association with maternal folate status. Among children born to women who were vitamin B-12 deficient at baseline, the percent difference in HOMA-IR compared to the control group was 15.1% (95% CI: -35.9, 106.4), 4.9% (-41.6, 88.5), 3.3% (-38.4, 73.5), and 18.1% (-29.0, 96.7) in the folic acid, folic acid-iron, folic acid-iron-zinc, and multiple micronutrient supplementation groups, respectively, none of which were significant. Maternal vitamin B-12 deficiency is associated with an elevated risk of insulin resistance, but supplementation with folic acid or other micronutrients led to no significant change in insulin resistance in school-aged offspring.
    Journal of Nutrition 08/2011; 141(10):1912-7. · 3.92 Impact Factor
  • Article: Newborn vitamin A supplementation does not affect nasopharyngeal carriage of Streptococcus pneumoniae in Bangladeshi infants at age 3 months.
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    ABSTRACT: Nasopharyngeal (NP) carriage of S. pneumoniae (Spn) is a risk factor for pneumococcal disease and its transmission. We assessed the impact of vitamin A (VA) supplementation shortly after birth in reducing Spn colonization in early infancy in rural Bangladesh. We recruited 500 infants participating in a cluster-randomized trial that reported a 15% reduction in mortality following receipt of an oral dose of VA (52.25 μmol) compared to placebo. NP specimens were collected at the age of 3 mo to study the effect of VA on the prevalence of culture-confirmed Spn. Analyses were conducted by intention to treat. Spn carriage prevalence did not differ between VA and placebo recipients [OR = 0.83 (95% CI: 0.55-1.27); P = 0.390]. Spn carriage at the age of 3 mo was not lowered by VA given at birth. Results are similar to those from an Indian study in which impact on Spn carriage was assessed at the age of 4 mo [OR = 0.73 (95% CI: 0.48-1.10); P = 0.128]. The point estimate of the pooled effect size for the 2 studies is OR = 0.78 [(95% CI: 0.58-1.04); P = 0.095], which may imply a modest impact on carriage. If so, then the evidence thus far would suggest that Spn carriage reduction is unlikely to be a primary ancillary benefit of newborn VA supplementation.
    Journal of Nutrition 08/2011; 141(10):1907-11. · 3.92 Impact Factor
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    Article: Bioelectrical impedance among rural Bangladeshi Women during pregnancy and in the postpartum period.
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    ABSTRACT: Properties of bioelectrical impedance analysis (BIA) reflect body-composition and may serve as stand-alone indicators of maternal health. Despite these potential roles, BIA properties during pregnancy and lactation in rural South Asian women have not been described previously, although pregnancy and infant health outcomes are often compromised. This paper reports the BIA properties among a large sample of pregnant and postpartum women of rural Bangladesh, aged 12-46 years, participating in a substudy of a community-based, placebo-controlled trial of vitamin A or beta-carotene supplementation. Anthropometry and single frequency (50 kHz) BIA were assessed in 1,435 women during the first trimester (< or =12 weeks gestation), in 1237 women during the third trimester (32-36 weeks gestation), and in 1,141 women at 12-18 weeks postpartum. Resistance and reactance were recorded, and impedance and phase angle were calculated. Data were examined cross-sectionally to maximize sample-size at each timepoint, and the factors relating to BIA properties were explored. Women were typically young, primiparous and lacking formal education (22.2 +/- 6.3 years old, 42.2% primiparous, and 39.7% unschooled among the first trimester participants). Weight (kg), resistance (omega), and reactance (omega) were 42.1 +/- 5.7, 688 +/- 77, and 73 +/- 12 in the first trimester; 47.7 +/- 5.9, 646 +/- 77, and 64 +/- 12 in the third trimester; and 42.7 +/- 5.6, 699 +/- 79, and 72 +/- 12 postpartum respectively. Resistance declined with age and increased with body mass index. Resistance was higher than that observed in other, non-Asian pregnant populations, likely reflecting considerably smaller body-volume among Bangladeshi women. Resistance and reactance decreased in advanced stage of pregnancy as the rate of gain in weight increased, returning to the first trimester values by the three months postpartum. Normative distributions of BIA properties are presented for rural Bangladeshi women across a reproductive cycle that may be related to pregnancy outcomes and ultimately be used for assessing body-composition in this population.
    Journal of Health Population and Nutrition 06/2011; 29(3):236-44. · 0.95 Impact Factor
  • Article: Effects of vitamin A or beta carotene supplementation on pregnancy-related mortality and infant mortality in rural Bangladesh: a cluster randomized trial.
    [show abstract] [hide abstract]
    ABSTRACT: Maternal vitamin A deficiency is a public health concern in the developing world. Its prevention may improve maternal and infant survival. To assess efficacy of maternal vitamin A or beta carotene supplementation in reducing pregnancy-related and infant mortality. Cluster randomized, double-masked, placebo-controlled trial among pregnant women 13 to 45 years of age and their live-born infants to 12 weeks (84 days) postpartum in rural northern Bangladesh between 2001 and 2007. Interventions Five hundred ninety-six community clusters (study sectors) were randomized for pregnant women to receive weekly, from the first trimester through 12 weeks postpartum, 7000 μg of retinol equivalents as retinyl palmitate, 42 mg of all-trans beta carotene, or placebo. Married women (n = 125,257) underwent 5-week surveillance for pregnancy, ascertained by a history of amenorrhea and confirmed by urine test. Blood samples were obtained from participants in 32 sectors (5%) for biochemical studies. All-cause mortality of women related to pregnancy, stillbirth, and infant mortality to 12 weeks (84 days) following pregnancy outcome. Groups were comparable across risk factors. For the mortality outcomes, neither of the supplement group outcomes was significantly different from the placebo group outcomes. The numbers of deaths and all-cause, pregnancy-related mortality rates (per 100,000 pregnancies) were 41 and 206 (95% confidence interval [CI], 140-273) in the placebo group, 47 and 237 (95% CI, 166-309) in the vitamin A group, and 50 and 250 (95% CI, 177-323) in the beta carotene group. Relative risks for mortality in the vitamin A and beta carotene groups were 1.15 (95% CI, 0.75-1.76) and 1.21 (95% CI, 0.81-1.81), respectively. In the placebo, vitamin A, and beta carotene groups the rates of stillbirth and infant mortality were 47.9 (95% CI, 44.3-51.5), 45.6 (95% CI, 42.1-49.2), and 51.8 (95% CI, 48.0-55.6) per 1000 births and 68.1 (95% CI, 63.7-72.5), 65.0 (95% CI, 60.7-69.4), and 69.8 (95% CI, 65.4-72.3) per 1000 live births, respectively. Vitamin A compared with either placebo or beta carotene supplementation increased plasma retinol concentrations by end of study (1.46 [95% CI, 1.42-1.50] μmol/L vs 1.13 [95% CI, 1.09-1.17] μmol/L and 1.18 [95% CI, 1.14-1.22] μmol/L, respectively; P < .001) and reduced, but did not eliminate, gestational night blindness (7.1% for vitamin A vs 9.2% for placebo and 8.9% for beta carotene [P < .001 for both]). Use of weekly vitamin A or beta carotene in pregnant women in Bangladesh, compared with placebo, did not reduce all-cause maternal, fetal, or infant mortality. clinicaltrials.gov Identifier: NCT00198822.
    JAMA The Journal of the American Medical Association 05/2011; 305(19):1986-95. · 30.03 Impact Factor

Institutions

  • 2002–2013
    • Johns Hopkins University
      • • Department of Pediatrics
      • • Center for Human Nutrition
      • • Department of Medicine
      • • Department of International Health
      Baltimore, MD, USA
  • 2002–2012
    • Johns Hopkins Bloomberg School of Public Health
      Baltimore, MD, USA
    • Johns Hopkins Medicine
      • Department of International Health
      Baltimore, MD, USA
  • 2011
    • University of California, Davis
      • Program in International and Community Nutrition
      Davis, CA, USA
  • 2010
    • Fred Hutchinson Cancer Research Center
      Seattle, WA, USA
    • Columbia University
      • College of Physicians and Surgeons
      New York City, NY, USA
  • 2007
    • University of Maryland-School of Medicine
      Baltimore, MD, USA