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Semple S.,University of Aberdeen | Semple S.,Institute of Occupational Medicine | Devakumar D.,University College London | Fullerton D.G.,Clinical Research Laboratories | And 7 more authors.
Environmental Health Perspectives | Year: 2010

BACKGROUND: About half of the world's population is exposed to smoke from burning biomass fuels at home. The high airborne particulate levels in these homes and the health burden of exposure to this smoke are well described. Burning unprocessed biological material such as wood and dried animal dung may also produce high indoor endotoxin concentrations. OBJECTIVE: In this study we measured airborne endotoxin levels in homes burning different biomass fuels. METHODS: Air sampling was carried out in homes burning wood or dried animal dung in Nepal (n = 31) and wood, charcoal, or crop residues in Malawi (n = 38). Filters were analyzed for endotoxin content expressed as airborne endotoxin concentration and endotoxin per mass of airborne particulate. RESULTS: Airborne endotoxin concentrations were high. Averaged over 24 hr in Malawian homes, median concentrations of total inhalable endotoxin were 24 endotoxin units (EU)/m3 in charcoal-burning homes and 40 EU/m3 in wood-burning homes. Short cooking-time samples collected in Nepal produced median values of 43 EU/m3 in wood-burning homes and 365 EU/m3 in dung-burning homes, suggesting increasing endotoxin levels with decreasing energy levels in unprocessed solid fuels. CONCLUSIONS: Airborne endotoxin concentrations in homes burning biomass fuels are orders of magnitude higher than those found in homes in developed countries where endotoxin exposure has been linked to respiratory illness in children. There is a need for work to identify the determinants of these high concentrations, interventions to reduce exposure, and health studies to examine the effects of these sustained, near-occupational levels of exposure experienced from early life.


Devakumar D.,University College London | Stocks J.,University College London | Ayres J.G.,University of Birmingham | Kirkby J.,University College London | And 8 more authors.
European Respiratory Journal | Year: 2015

A randomised trial of prenatal multiple micronutrient supplementation in Nepalese women increased birthweight and weight at 2 years of age in offspring, compared to those born to mothers who only received iron and folic acid supplements. Further follow-up of this cohort provided an opportunity to investigate the effect of antenatal multiple micronutrients on subsequent lung function by measuring spirometry at 7-9 years of age in children born during the trial. 841 children (80% of the cohort) were seen at mean±SD 8.5±0.4 years. Technically successful spirometry results were obtained in 793 (94.3%) children, 50% of whom had been randomised to micronutrient supplementation. Background characteristics, including anthropometry, were similar in the two allocation groups. Lung function was also similar, mean (95% CI) difference in z-scores (supplementation minus control) was -0.08 (-0.19-0.04), -0.05 (-0.17-0.06) and -0.04 (-0.15-0.07) for forced expiratory volume in 1 s (FEV1), forced vital capacity and FEV1/FVC, respectively. Compared with healthy white children, FEV1 and FVC in the "healthy" Nepalese children were ∼1 (∼13%) z-score lower, with no difference in FEV1/FVC. We conclude that, compared with routine iron and folic acid, multiple micronutrient supplementation during pregnancy has no effect on spirometric lung function in Nepalese children at 8.5 years of age. Copyright ©ERS 2015.


PubMed | University of Birmingham, Roosevelt University, Mother and Infant Research Activities, University College London and University of Aberdeen
Type: | Journal: Environment international | Year: 2014

The exposure of children to air pollution in low resource settings is believed to be high because of the common use of biomass fuels for cooking. We used microenvironment sampling to estimate the respirable fraction of air pollution (particles with median diameter less than 4 m) to which 7-9 year old children in southern Nepal were exposed. Sampling was conducted for a total 2649 h in 55 households, 8 schools and 8 outdoor locations of rural Dhanusha. We conducted gravimetric and photometric sampling in a subsample of the children in our study in the locations in which they usually resided (bedroom/living room, kitchen, veranda, in school and outdoors), repeated three times over one year. Using time activity information, a 24-hour time weighted average was modeled for all the children in the study. Approximately two-thirds of homes used biomass fuels, with the remainder mostly using gas. The exposure of children to air pollution was very high. The 24-hour time weighted average over the whole year was 168 g/m(3). The non-kitchen related samples tended to show approximately double the concentration in winter than spring/autumn, and four times that of the monsoon season. There was no difference between the exposure of boys and girls. Air pollution in rural households was much higher than the World Health Organization and the National Ambient Air Quality Standards for Nepal recommendations for particulate exposure.


PubMed | University of Aberdeen, Mother and Infant Research Activities, University College London and University of Birmingham
Type: Journal Article | Journal: The European respiratory journal | Year: 2015

A randomised trial of prenatal multiple micronutrient supplementation in Nepalese women increased birthweight and weight at 2years of age in offspring, compared to those born to mothers who only received iron and folic acid supplements. Further follow-up of this cohort provided an opportunity to investigate the effect of antenatal multiple micronutrients on subsequent lung function by measuring spirometry at 7-9years of age in C: hildren born during the trial. 841 children (80% of the cohort) were seen at meansd 8.50.4 years. Technically successful spirometry results were obtained in 793 (94.3%) children, 50% of whom had been randomised to micronutrient supplementation. Background characteristics, including anthropometry, were similar in the two allocation groups. Lung function was also similar, mean (95% CI) difference in z-scores (supplementation minus control) was -0.08 (-0.19-0.04), -0.05 (-0.17-0.06) and -0.04 (-0.15-0.07) for forced expiratory volume in 1s (FEV1), forced vital capacity and FEV1/FVC, respectively. Compared with healthy white children, FEV1 and FVC in the healthy Nepalese children were 1 (13%) z-score lower, with no difference in FEV1/FVC. We conclude that, compared with routine iron and folic acid, multiple micronutrient supplementation during pregnancy has no effect on spirometric lung function in Nepalese children at 8.5years of age.


Devakumar D.,University College London | Chaube S.S.,Mother and Infant Research Activities | Wells J.C.K.,University College London | Saville N.M.,University College London | And 4 more authors.
The Lancet Global Health | Year: 2014

Background: In 2002-04, we did a randomised controlled trial in southern Nepal, and reported that children born to mothers taking multiple micronutrient supplements during pregnancy had a mean birthweight 77g greater than children born to mothers taking iron and folic acid supplements. Children born to mothers in the study group were a mean 204g heavier at 2·5 years of age and their systolic blood pressure was a mean 2·5mm Hg lower than children born to mothers in the control group. We aimed to follow up the same children to mid-childhood age 8·5 years to investigate whether these differences would be sustained. Methods: For this follow-up study, we identified children from the original trial and measured anthropometry, body composition with bioelectrical impedance with population-specific isotope calibration, blood pressure, and renal dimensions by ultrasound. We documented socioeconomic status, household food security, and air pollution. Main outcomes of the follow-up at 8 years were Z scores for weight-for-age, height-for-age, and body-mass index BMI-forage according to WHO Child Growth Standards for children aged 5-19 years, and blood pressure. This study is registered with the International Standard Randomised Controlled Trial register, number ISRCTN88625934. Findings: Between Sept 21, 2011, and Dec 7, 2012, we assessed 841 children 422 in the control group and 419 in the intervention group. Unadjusted differences intervention minus control in Z scores were 0·05 for weight-for-age 95% CI -0·09 to 0·19, 0·02 in height-for-age -0·10 to 0·15, and 0·04 in BMI-for-age -0·09 to 0·18. We recorded no difference in blood pressure. Adjusted differences were similar for all outcomes. Interpretation: We recorded no differences in phenotype between children born to mothers who received antenatal multiple micronutrient or iron and folate supplements at age 8·5 years. Our findings did not extend to physiological differences or potential longer-term effects. Funding: The Wellcome Trust. © Devakumar et al.


PubMed | Ludwig Maximilians University of Munich, Mother and Infant Research Activities and University College London
Type: Journal Article | Journal: The Journal of nutrition | Year: 2016

Recent research has highlighted the need for additional studies on the nutrition input required to stabilize growth.Our objective was to examine the association between dietary diversity and conditional growth in children aged 0-89 mo.We analyzed cohort data from 529 mothers and children living in a remote and food-insecure region in the mountains of Nepal. Children were aged 0-59 mo at baseline and were followed up after 9 and 29 mo. Conditional growth was calculated as the deviation from the expected height-for-age difference (HAD) trajectory based on previous measures of HAD and the pattern of growth in the population. Dietary diversity was assessed with the use of a count of the foods consumed from 7 food groups in the previous 7 d. The association between dietary diversity and conditional growth during the 2 follow-up periods (of 9 and 20 mo, respectively) was estimated with the use of ordinary least-squares regressions.Prevalence of stunting and absolute height deficits was very high and increased over the course of the study. At the last measurement (age range 29-89 mo), 76.5% were stunted and the mean SD HAD was -11.7 4.6 cm. Dietary diversity was associated positively with conditional growth in the later (May 2012-December 2013) but not the earlier (July 2011-May 2012) growth period. Childrens ages ranged from 0 to 59 mo in July 2011, 9 to 69 mo in May 2012, and 29 to 89 mo in December 2013. After adjustment, increasing the dietary diversity by one food group was associated with a 0.09 cm (95% CI: 0.00, 0.17 cm) increase in conditional growth in the second growth period.Increasing dietary diversity for children reduces the risk of stunting and improves growth after growth faltering. Future efforts should be directed at enabling families in food-insecure areas to feed their children a more diverse diet.


PubMed | University College London, University of Cambridge and Mother and Infant Research Activities
Type: Journal Article | Journal: American journal of human biology : the official journal of the Human Biology Council | Year: 2016

Factors acting before children are born or reach school-going age may explain why some do not complete primary education. Many relevant factors relate to maternal phenotype, but few studies have tested for independent associations of maternal factors relative to those characterizing the family in general.Using data from a longitudinal study of 838 children in Dhanusha, Nepal, we used logistic regression models to test whether indices of maternal somatic and educational capital, or family economic capital, were independently associated with children having had 2 versus 3+ years of schooling at a mean age of 8.5 years. We also tested whether maternal age, childrens early growth, and urban/rural location mediated such associations.Children had a higher risk of completing less schooling if their mothers were short, thin, anemic, and uneducated. Independently, lower family material assets and land acreage also increased childrens odds of less schooling. There was an indication of gender differences, with the risk of poor educational attainment in girls associated with low maternal somatic and educational capital, whereas in boys the relevant factors were low maternal education and family land ownership.Our analysis demonstrates that, independent of broader indices of family capital such as land or material assets, childrens educational attainment is associated with factors embodied in maternal phenotype. Both somatic and educational maternal capital appeared important. A composite index of maternal capital could provide a new measurable proxy, prior to school entry, for identifying children at risk of completing fewer years of schooling. Am. J. Hum. Biol. 28:687-698, 2016. 2016 Wiley Periodicals, Inc.


PubMed | Mother and Infant Research Activities and University College London
Type: | Journal: PeerJ | Year: 2015

Background. Body composition is important as a marker of both current and future health. Bioelectrical impedance (BIA) is a simple and accurate method for estimating body composition, but requires population-specific calibration equations. Objectives. (1) To generate population specific calibration equations to predict lean mass (LM) from BIA in Nepalese children aged 7-9 years. (2) To explore methodological changes that may extend the range and improve accuracy. Methods. BIA measurements were obtained from 102 Nepalese children (52 girls) using the Tanita BC-418. Isotope dilution with deuterium oxide was used to measure total body water and to estimate LM. Prediction equations for estimating LM from BIA data were developed using linear regression, and estimates were compared with those obtained from the Tanita system. We assessed the effects of flexing the arms of children to extend the range of coverage towards lower weights. We also estimated potential error if the number of children included in the study was reduced. Findings. Prediction equations were generated, incorporating height, impedance index, weight and sex as predictors (R (2) 93%). The Tanita system tended to under-estimate LM, with a mean error of 2.2%, but extending up to 25.8%. Flexing the arms to 90 increased the lower weight range, but produced a small error that was not significant when applied to children <16 kg (p 0.42). Reducing the number of children increased the error at the tails of the weight distribution. Conclusions. Population-specific isotope calibration of BIA for Nepalese children has high accuracy. Arm position is important and can be used to extend the range of low weight covered. Smaller samples reduce resource requirements, but leads to large errors at the tails of the weight distribution.


PubMed | Nagoya University, Mother and Infant Research Activities and University College London
Type: Journal Article | Journal: Rural and remote health | Year: 2014

Low birth weight (LBW) is a major risk factor for neonatal death. However, most neonates in low-income countries are not weighed at birth. This results in many LBW infants being overlooked. Female community health volunteers (FCHVs) in Nepal are non-health professionals who are living in local communities and have already worked in a field of reproductive and child health under the government of Nepal for more than 20 years. The effectiveness of involving FCHVs to detect LBW infants and to initiate prompt action for their care was studied in rural areas of Nepal.FCHVs were tasked with weighing all neonates born in selected areas using color-coded spring scales. Supervisors repeated each weighing using electronic scales as the gold standard comparator. Data on the relative birth sizes of the infants, as assessed by their mothers, were also collected and compared with the measured weights. Each of the 205 FCHVs involved in the study was asked about the steps that she would take when she came across a LBW infant, and knowledge of zeroing a spring scale was also assessed through individual interviews. The effect of the background social characteristics of the FCHVs on their performance was examined by logistic regression. This study was nested within a community-based neonatal sepsis-management intervention surveillance system, which facilitated an assessment of the performance of the FCHVs in weighing neonates, coverage of FCHVs visits, and weighing of babies through maternal interviews.A total of 462 babies were weighed, using both spring scales and electronic scales, within 72 hours of birth. The prevalence of LBW, as assessed by the gold standard method, was 28%. The sensitivity of detection of LBW by FCHVs was 89%, whereas the sensitivity of the mothers perception of size at birth was only 40%. Of the 205 FCHVs participating in the study, 70% of FCHVs understood what they should do when they identified LBW and very low birth weight (VLBW) infants. Ninety-six per cent could describe how to zero a scale and approximately 50% could do it correctly. Seventy-seven per cent of FCHVs weighed infants at least once during the study period, and 19 of them (12%) miscategorized infant weights. Differences were not detected between the background social characteristics of FCHVs who miscategorized infants and those who did not. On the basis of maternal reporting, 67% of FCHVs who visited infants had weighed them.FCHVs are able to correctly identify LBW and VLBW infants using spring scales and describe the correct steps to take after identification of these infants. Use of FCHVs as newborn care providers allows for utilization of their logistical, geographical, and cultural strengths, particularly a high level of access to neonates, that can complement the Nepalese healthcare system. Providing additional training to and increasing supervision of local FCHVs regarding birth weight measurement will increase the identification of high-risk neonates in resource-limited settings.


PubMed | Mother and Infant Research Activities and University College London
Type: Journal Article | Journal: American journal of human biology : the official journal of the Human Biology Council | Year: 2016

Growth patterns in early life are increasingly linked with subsequent cardio-metabolic risk, but the underlying mechanisms require elucidation. We have developed a theoretical model of blood pressure, treating it as a function of homeostatic metabolic capacity, and antagonistic metabolic load. We sought to differentiate prenatal and postnatal components of metabolic capacity, and to identify intergenerational contributions to offspring capacity and load.We followed up at 8 years a cohort of children originally recruited into a randomized trial of maternal micronutrient supplementation in pregnancy. Maternal anthropometry was measured at recruitment. Offspring anthropometry was measured at birth, 2 years and 8 years. Offspring blood pressure, kidney size, and body composition were measured at 8 years. Regression analysis was used to investigate potential associations of maternal phenotype, birth phenotype, and current body composition with kidney size and blood pressure.Blood pressure was positively associated with body fat, but negatively associated with birth weight and relative leg length. Kidney size was positively associated with birth weight but not with relative leg length. Adjusting for adiposity, blood pressure was independently negatively associated with birth weight, relative leg length, and kidney length. Maternal height and BMI predicted offspring size at birth and at 8 years, but not blood pressure.Our data provide support for the capacity-load model of blood pressure in Nepalese children. Fetal and postnatal growth and kidney dimensions all contribute to metabolic capacity. Maternal phenotype contributed to offspring capacity and load, but these associations did not propagate to blood pressure. Am. J. Hum. Biol. 28:555-565, 2016. 2016 The Authors American Journal of Human Biology Published by Wiley Periodicals, Inc.

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