Infant infections, respiratory symptoms, and allergy in relation to timing of rice cereal introduction in a United States cohort

Comparison of direct effects of rice-thickened formula vs routine feeds on symptoms and gastroesophageal reflux indices: A crossover cohort study

BACKGROUND

We compared the direct effects of routine vs rice-thickened formula on 24-h pH-impedance and symptom characteristics and then examined if dietary effects were modified by acid reflux index severity in infants.

METHODS

Forty infants under consideration for gastroesophageal reflux disease and therapies were evaluated at 43 ± 1 weeks postmenstrual age. Each infant was equally fed routine diet and thickened formula during evaluations. Postprandial sessions were analyzed for acid reflux index, reflux events, clearance times, distal baseline impedance, and symptoms.

RESULTS

Thickened formula has no effect (P ≥ 0.05) on acid reflux events' characteristics or overall symptom frequency. However, refluxate height and frequency of weakly acidic events and cough were decreased (P < 0.05). Prolonged bolus clearance and a decrease in distal baseline impedance were noted with thickened feeds (vs routine feeds) when acid reflux index was >7 (P < 0.05).

CONCLUSION

Our pH-impedance testing protocol identifies direct effects of potential therapies at the point of care. Acutely, thickened formula does not impact acid-specific reflux indices but decreases full-column reflux and cough reflexes. In those with an acid reflux index of >7, thickened formula prolongs the distal esophageal bolus clearance (the mechanisms of which are uncertain). Clinical trials are needed to clarify objective indications and therapeutic use of thickened formulas for infants with gastroesophageal reflux disease, along with short- and long-term side effects.

Contribution of gut bacteria to arsenic metabolism in the first year of life in a prospective birth cohort

Gut bacteria are at the interface of environmental exposures and their impact on human systems, and may alter host absorption, metabolism, and excretion of toxic chemicals. We investigated whether arsenic-metabolizing bacterial gene pathways related to urinary arsenic concentrations. In the New Hampshire Birth Cohort Study, urine and stool samples were obtained at six weeks (n = 186) and one year (n = 190) of age. Inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), and arsenobetaine (AsB) were quantified in infant urine samples using high-performance liquid chromatography with inductively coupled plasma mass spectrometry. Total arsenic exposure (tAs) was summarized as Σ(iAs, MMA, DMA) and log2-transformed. Fecal microbial DNA underwent metagenomic sequencing and the relative abundance of bacterial gene pathways were grouped as KEGG Orthologies (KOs) using BioBakery algorithms. Arsenic metabolism KOs with >80% prevalence were log2-transformed and modeled continuously using linear regression, those with <10% were not evaluated and those with 10-80% prevalence were analyzed dichotomously (detect/non-detect) using logistic regression. In the first set of models, tAs was regressed against KO relative abundance or detection adjusting for age at sample collection and child's sex. Effect modification by delivery mode was assessed in stratified models. In the second set of models, the association between the relative abundance/detection of the KOs and arsenic speciation (%iAs, %MMA, %DMA) was quantified with linear regression. Urinary tAs was associated with the increased relative abundance/detection odds of several arsenic-related KOs, including K16509, an arsenate reductase transcriptional regulator, with stronger associations among six-week-olds than one-year-olds. K16509 was also associated with decreased %MMA and increased %DMA at six weeks and one year. Notably, many associations were stronger among operatively-delivered than vaginally-delivered infants. Our findings suggest associations between arsenic-metabolizing bacteria in the infant gut microbiome and urinary arsenic excretion.

Dietary Exposure to Toxic Elements and the Health of Young Children: Methodological Considerations and Data Needs

Concerns have been raised regarding toxic-element (arsenic, cadmium, lead, and mercury) contamination of commercially available infant foods around the world. Young children are vulnerable to the effects of toxic elements, based on higher absorption levels and potentially poorer detoxification capacities. Toxic-element exposures in early life exact high societal costs, but it is unclear how much dietary exposure to these elements contributes to adverse health outcomes. Well-designed epidemiological studies conducted in different geographical and socioeconomic contexts need to estimate dietary toxicant exposure in young children and to determine whether causal links exist between toxicants in children's diets and health outcomes. This commentary outlines the methodological considerations and data needs to advance such research.

Mothers' feeding practices among infants (4-12 months) and associated factors: a cross-sectional study in Saudi Arabia

A global target of increasing exclusive breast-feeding (EBF) to at least 50 % by the year 2025 was set by the WHO for infants under 6 months. The lowest prevalence in the world was found in the Eastern Mediterranean region in 2010-18 and little is known about the status of mothers' feeding practices in Saudi Arabia. The present study aimed to assess mothers' actual feeding and weaning practices used with their infants by the mothers' different age groups. The present study was conducted among 247 mothers of infants aged 4-12 months who were attending public well-baby clinics. Quantitative data were obtained by nutritionists using an electronic semi-structured questionnaire about mothers' feeding practices. Only 5·3 % of mothers engaged in EBF, 44·9 % breast-fed their infants after an hour of birth, while 92·7 % of infants had ever been breast-fed. The average intent/plan to continue breast-feeding was 4·9(±3·1) months. Younger mothers introduced weaning food around 4 weeks earlier than older mothers (mean differences were -0·4, 95 % CI -0·71, -0·13; P = 0·031). A total of 64·3 % of infants received complementary feeding before completing 17 weeks. Maternal age group and delivery mode were the only factors associated with the early introduction of complementary feeding. A total of 69·2 % of the mothers believed that 'it is a good time' and 61·1 % felt that 'infants are hungry and need other sources of food'. Online sources and family advice were the top sources of information on mothers' feeding practices. Provision of professional advice about EBF and optimal weaning practices are significant areas for improvement in terms of compliance with recommended infant feeding practices.