Placing a Lens on the First 1000 Days of Life: Prenatal Intake, Infant Feeding, the Microbiome and Child Growth

The first 1000 days of life, from conception until the child’s second birthday, constitute a critical window for child growth and development. During infancy and early childhood, significant and rapid physical changes occur, including increases in weight, height, and brain size and organ development accompanied by cognitive and psychomotor development. Adequate infant feeding, including breastfeeding and complementary feeding, that meets the infants’ energy and nutrient requirements can help protect against growth faltering, infant and child morbidity and mortality, and delayed mental and motor development. Adequate nutrition during this critical period can also protect against adverse health outcomes and chronic diseases later in life according to the hypothesis of developmental origins of health and disease. A web of factors that are country- and culture- specific influence infant feeding practices and child growth. Further, the microbiome has been suggested as a strong potential player in the association between infant nutrition and child growth. Therefore, the overarching theme of the current dissertation is to investigate hypotheses that can provide evidence to inform the paradigm linking socio-demographic, maternal, and child determinants including prenatal intake to infant feeding, the breast milk and infant gut microbiome, and child growth within the first 1000 days of life. Specifically, aims one and two examine the socio-demographic, maternal, and child determinants of child growth and breastfeeding in a cross-sectional survey of mother-child dyads in Lebanon, a middle-income country undergoing nutrition transition in the Middle East. The third aim focuses on the CHILD cohort study, a multi-center longitudinal prospective birth cohort study, to examine the associations between prenatal diet and supplement intake and the breast milk microbiome. Finally, the fourth aim is to review the evidence for the potential of the infant gut microbiome as a promising target linking complementary feeding to child undernutrition in low- and middleincome countries (LMIC) with the highest burden of undernutrition. The results for aim one revealed sex-specific determinants of child growth in Lebanon. The determinants examined through a hierarchical conceptual framework included: maternal and paternal education among boys and crowding index among girls at the distal sociodemographic level, and maternal obesity among girls at the intermediate maternal level. The proximal child determinants included birth length, number of children in the household and breastfeeding duration among girls, birthweight among boys and child’s age among boys and girls. In the analysis for aim two, breastfeeding practices were suboptimal in Lebanon as less than half (41.5%) of the infants were exclusively breastfed during the 40-day rest period and 12.3% were exclusively breastfed during the 6-month duration recommended by the World Health Organization. Higher socioeconomic status, as reflected by a larger number of cars owned, and Csection delivery were consistently inversely associated with lower odds of exclusive breastfeeding for 40 days and 6 months. Belonging to a family with more children was associated with higher odds of exclusive breastfeeding for 40 days; while maternal overweight and obesity were associated with lower odds of exclusive breastfeeding for 6 months

A scoping review of reporting ‘Ethical Research Practices’ in research conducted among refugees and war-affected populations in the Arab world

Abstract Background Ethical research conduct is a cornerstone of research practice particularly when research participants include vulnerable populations. This study mapped the extent of reporting ethical research practices in studies conducted among refugees and war-affected populations in the Arab World, and assessed variations by time, country of study, and study characteristics. Methods An electronic search of eight databases resulted in 5668 unique records published between 2000 and 2013. Scoping review yielded 164 eligible articles for analyses. Results Ethical research practices, including obtaining institutional approval, access to the community/research site, and informed consent/assent from the research participants, were reported in 48.2, 54.9, and 53.7% of the publications, respectively. Institutional approval was significantly more likely to be reported when the research was biomedical in nature compared to public health and social (91.7% vs. 54.4 and 32.4%), when the study employed quantitative compared to qualitative or mixed methodologies (61.7% vs. 26.8 and 42.9%), and when the journal required a statement on ethical declarations (57.4% vs. 27.1%). Institutional approval was least likely to be reported in papers that were sole-authored (9.5%), when these did not mention a funding source (29.6%), or when published in national journals (0%). Similar results were obtained for access to the community site and for seeking informed consent/assent from study participants. Conclusions The responsibility of inadequacies in adherence to ethical research conduct in crisis settings is born by a multitude of stakeholders including funding agencies, institutional research boards, researchers and international relief organizations involved in research, as well as journal editors, all of whom need to play a more proactive role for enhancing the practice of ethical research conduct in conflict settings

Development of an automated system for the analysis of inorganic chloramines in swimming pools via multi-syringe chromatography and photometric detection with ABTS

International audienceInorganic chloramines are disinfection by-products resulting from the unwanted reaction between chlorine used as disinfectant in swimming pools and nitrogenous compounds brought by bathers. This parameter (total chloramines or combined chlorine) is currently measured on site by a colorimetric method that does not allow to measure only inorganic chloramines. In this paper, a multi-syringe chromatography system combined with a post column derivatization is applied for the first time for the specific detection of the three individual inorganic chloramines (monochloramine, dichloramine and trichloramine). These latter ones are separated using a low-pressure monolithic C18 column, and separately detected after a post-column reaction with the chromogenic reagent ABTS (2,2'-azino-bis-(3-ethyl-benzothiazoline)-6-sulfonic acid-diammonium salt). Development of two ABTS reagents provides discrimination of chlorine and monochloramine that are not separated on the column. Optimization of the experimental conditions enables determination of inorganic chloramines with very good detection limits (around 10 µg eq.Cl2 L-1) without interferences from other chlorinated compounds such as organic chloramines or free available chlorine. The validation of the whole procedure has been successfully applied to real swimming pools samples

Prioritizing Variables for Observational Study Design using the Joint Variable Importance Plot

Observational studies of treatment effects require adjustment for confounding variables. However, causal inference methods typically cannot deliver perfect adjustment on all measured baseline variables, and there is often ambiguity about which variables should be prioritized. Standard prioritization methods based on treatment imbalance alone neglect variables’ relationships with the outcome. We propose the joint variable importance plot to guide variable prioritization for observational studies. Since not all variables are equally relevant to the outcome, the plot adds outcome associations to quantify the potential confounding jointly with the standardized mean difference. To enhance comparisons on the plot between variables with different confounding relationships, we also derive and plot bias curves. Variable prioritization using the plot can produce recommended values for tuning parameters in many existing matching and weighting methods. We showcase the use of the joint variable importance plots in the design of a balance-constrained matched study to evaluate whether taking an antidiabetic medication, glyburide, increases the incidence of C-section delivery among pregnant individuals with gestational diabetes.</p

Validity and Reproducibility of a Culture-Specific Food Frequency Questionnaire in Lebanon

This study aims to assess the validity and reproducibility of a culture-specific semi-quantitative food frequency questionnaire (FFQ) for Lebanese adults. The 94-item FFQ captures intake of traditional Mediterranean dishes and Western food, reflective of current Lebanese nutrition transition. Among 107 participants (18&ndash;65 years), the FFQ was administered at baseline (FFQ-1) and one year thereafter (FFQ-2); 2&ndash;3 24-h recalls (24-HRs)/season were collected for a total of 8&ndash;12 over four seasons. A subset (n = 67) provided a fasting blood sample in the fall. Spearman-correlation coefficients, Bland&ndash;Altman plots, joint-classification and (ICC) were calculated. Mean intakes from FFQ-2 were higher than from the total 24-HRs. Correlations for diet from FFQ-2 and 24-HRs ranged from 0.17 for &alpha;-carotene to 0.65 for energy. Joint classification in the same/adjacent quartile ranged from 74.8% to 95%. FFQ-2-plasma carotenoid correlations ranged from 0.18 for lutein/zeaxanthin to 0.59 for &beta;-carotene. Intra-class correlations for FFQ-1 and FFQ-2 ranged from 0.36 for &beta;-cryptoxanthin to 0.85 for energy. 24-HRs carotenoid intake varied by season; combining season-specific 24-HRs proximal to biospecimen collection to the FFQ-2 improved diet-biochemical correlations. By applying dietary data from two tools with biomarkers taking into consideration seasonal variation, we report a valid, reproducible Lebanese FFQ for use in diet-disease research

Longitudinal Associations of Plasma Phospholipid Fatty Acids in Pregnancy with Neonatal Anthropometry: Results from the NICHD Fetal Growth Studies&mdash;Singleton Cohort

Despite increasing interest in the health effects of polyunsaturated FAs (PUFAs), their roles in fetal and neonatal growth remain understudied. Within the NICHD Fetal Growth Studies&mdash;Singleton Cohort, we prospectively investigated the associations of individual and subclasses of plasma phospholipid PUFAs at gestational weeks (GW) 10&ndash;14, 15&ndash;26, 23&ndash;31, and 33&ndash;39 with neonatal anthropometric measures as surrogates for fetal growth among 107 women with gestational diabetes mellitus (GDM) and 214 non-GDM controls. Multivariable weighted linear regression models estimated the associations between plasma phospholipid PUFAs and neonatal anthropometric measures. Adjusted beta coefficients for phospholipid docosahexaenoic acid (DHA) per standard deviation (SD) increase at GW 23&ndash;31 in association with birthweight z-score, neonatal length, and neonatal fat mass were 0.25 (95% CI: 0.08&ndash;0.41), 0.57 (0.11&ndash;1.03) cm, and 54.99 (23.57&ndash;86.42) g, respectively; all false discovery rates (FDRs) &lt; 0.05. Estimated &Delta;5-desaturase activity per SD increase at GW 33&ndash;39 but not at other time points was positively associated with birthweight z-score: 0.29 (95% CI: 0.08&ndash;0.33); neonatal length: 0.61 (0.29&ndash;0.94) cm; and neonatal fat mass: 32.59 (8.21&ndash;56.96) g; all FDRs &lt; 0.05. Longitudinal analysis showed consistent results. Our findings suggest that mid-to-late pregnancy presented as critical windows for primarily diet-derived DHA and &Delta;5-desaturase activity in relation to neonatal anthropometric measures