Feeding Infants at the Breast or Feeding Expressed Human Milk: Long-Term Cognitive, Executive Function, and Eating Behavior Outcomes at Age 6 Years

Associations between particulate matter exposure during pregnancy and executive function of toddlers in a prospective cohort study

BACKGROUND

Exposure to particulate matter (PM) has been found to be associated with impaired cognitive function. However, limited evidence is available on the relationship between PM exposure in the prenatal period and toddler executive function (EF), and the potential influence of breastfeeding.

METHODS

The study included 1106 mother-toddler pairs recruited between 2015 and 2019. We assessed mothers' PM1, PM2.5, and PM10 prenatal exposure with a satellite-based dataset at a 1 × 1 km spatial resolution and assigned to participants based on residential addresses. Toddler EF was measured using the Behavior Rating Inventory of Executive Function for Preschoolers (BRIEF-P) questionnaire, higher BRIEF-P scores indicated poorer EF in toddlers. We determined the associations of PM exposure during pregnancy with BRIEF-P scores using multiple linear regression models.

RESULTS

In the first trimester, a 10 μg/m3 increase of PM was associated with 1.49 (95% confidence interval [CI]: 0.14-2.83; PM1), 0.68 (95% CI: 0.10-1.26; PM2.5), and 0.63 (95% CI: 0.07-1.20; PM10) elevated toddler global executive composite index scores, respectively. In the stratified analysis, a 10 μg/m3 increase in first trimester PM1 exposure was related to 0.54 (95% CI: 0.19-0.89) higher inhibition scores in toddlers who received complementary breastfeeding for less than six months and -0.15 (95% CI: 0.81-0.51) higher inhibition scores in toddlers who received complementary breastfeeding for six months or more (P for interaction: 0.046). Additionally, a 10 μg/m3 increment in first trimester PM1 exposure was related to 0.36 (95% CI: 0.13-0.59) higher emotional control scores in toddlers who received breastfeeding for less than 12 months and -0.54 (95% CI: 1.25-0.18) higher inhibition scores in toddlers who received breastfeeding for no less than 12 months (P for interaction: 0.043).

CONCLUSIONS

PM exposure during the first trimester, especially PM1, has been linked to lower toddler EF performance in toddlers; feeding with breast milk may be a potential protective measure.

Examining psychosocial pathways to explain the link between breastfeeding practices and child behaviour in a longitudinal cohort

OBJECTIVE

Breastfeeding is associated with reduced postpartum depression, stronger parent-child relationships, and fewer behavioral disorders in early childhood. We tested the mediating roles of postpartum depression and parent-child relationship in the association between breastfeeding practices and child behavior.

STUDY DESIGN

We used standardized questionnaire data from a subset of the CHILD Cohort Study (n = 1,573) to measure postpartum depression at 6 months, 1 year and 2 years, parent-child relationship 1 year and 2 years, and child behavior at 5 years using the Child Behavior Checklist (range 0-100). Breastfeeding practices were measured at 3 months (none, partial, some expressed, all direct at the breast), 6 months (none, partial, exclusive), 12 months, and 24 months (no, yes). Confounders included birth factors, maternal characteristics, and socioeconomic status.

RESULTS

Breast milk feeding at 3 or 6 months was associated with - 1.13 (95% CI: -2.19-0.07) to -2.14 (95% CI: -3.46, -0.81) lower (better) child behavior scores. Reduced postpartum depression at 6 months mediated between 11.5% and 16.6% of the relationship between exclusive breast milk feeding at 3 months and better child behavior scores. Together, reduced postpartum depression at 1 year and reduced parent-child dysfunction at 2 years mediated between 21.9% and 32.1% of the relationship between breastfeeding at 12 months and better child behavior scores.

CONCLUSION

Postpartum depression and parent-child relationship quality partially mediate the relationship between breastfeeding practices and child behavior. Breastfeeding, as well as efforts to support parental mental health and parent-child relationships, may help to improve child behavior.

Review on the Impact of Milk Oligosaccharides on the Brain and Neurocognitive Development in Early Life

Milk Oligosaccharides (MOS), a group of complex carbohydrates found in human and bovine milk, have emerged as potential modulators of optimal brain development for early life. This review provides a comprehensive investigation of the impact of milk oligosaccharides on brain and neurocognitive development of early life by synthesizing current literature from preclinical models and human observational studies. The literature search was conducted in the PubMed search engine, and the inclusion eligibility was evaluated by three reviewers. Overall, we identified 26 articles for analysis. While the literature supports the crucial roles of fucosylated and sialylated milk oligosaccharides in learning, memory, executive functioning, and brain structural development, limitations were identified. In preclinical models, the supplementation of only the most abundant MOS might overlook the complexity of naturally occurring MOS compositions. Similarly, accurately quantifying MOS intake in human studies is challenging due to potential confounding effects such as formula feeding. Mechanistically, MOS is thought to impact neurodevelopment through modulation of the microbiota and enhancement of neuronal signaling. However, further advancement in our understanding necessitates clinical randomized-controlled trials to elucidate the specific mechanisms and long-term implications of milk oligosaccharides exposure. Understanding the interplay between milk oligosaccharides and cognition may contribute to early nutrition strategies for optimal cognitive outcomes in children.

Beyond ingredients: Supramolecular structure of lipid droplets in infant formula affects metabolic and brain function in mouse models

Human milk beneficially affects infant growth and brain development. The supramolecular structure of lipid globules in human milk i.e., large lipid globules covered by the milk fat globule membrane, is believed to contribute to this effect, in addition to the supply of functional ingredients. Three preclinical (mouse) experiments were performed to study the effects of infant formula mimicking the supramolecular structure of human milk lipid globules on brain and metabolic health outcomes. From postnatal day 16 to 42, mouse offspring were exposed to a diet containing infant formula with large, phospholipid-coated lipid droplets (structure, STR) or infant formula with the same ingredients but lacking the unique structural properties as observed in human milk (ingredient, ING). Subsequently, in Study 1, the fatty acid composition in liver and brain membranes was measured, and expression of hippocampal molecular markers were analyzed. In Study 2 and 3 adult (Western-style diet-induced) body fat accumulation and cognitive function were evaluated. Animals exposed to STR compared to ING showed improved omega-3 fatty acid accumulation in liver and brain, and higher expression of brain myelin-associated glycoprotein. Early exposure to STR reduced fat mass accumulation in adulthood; the effect was more pronounced in animals exposed to a Western-style diet. Additionally, mice exposed to STR demonstrated better memory performance later in life. In conclusion, early life exposure to infant formula containing large, phospholipid-coated lipid droplets, that are closer to the supramolecular structure of lipid globules in human milk, positively affects adult brain and metabolic health outcomes in pre-clinical animal models.

Adherence to Screen Time and Physical Activity Guidelines is Associated with Executive Function in US Toddlers Participating in the STRONG Kids 2 Birth Cohort Study

OBJECTIVE

To test the hypothesis that healthy weight status and adherence to American Academy of Pediatrics (AAP) guidelines for diet and physical activity would extend to greater executive function (EF) at age 24 months.

STUDY DESIGN

Parents of 24-month-old children from the STRONG Kids 2 cohort study (n = 352) completed the Behavioral Rating Inventory of Executive Function for Preschoolers (BRIEF-P) and reported physical activities, diet, and screen time. Toddlers met AAP guidelines if they consumed at least 5 servings of fruits and vegetables, were physically active, refrained from sugar-sweetened beverages, and limited daily screen time to <60 minutes. Relationships between EF, 24-month weight status, and meeting AAP guidelines were tested independent of child sex, ethnicity, socioeconomic status, weight status at birth, and maternal pregnancy weight status.

RESULTS

Weight-for-length z-score had no effect on EF. Toddlers meeting the screen time guideline had greater EF (β, -0.125; 95% CI, 0.234 to -0.008), inhibitory self-control (β, -0.142; 95% CI, -0.248 to -0.029), and emergent metacognition (β, -0.111; 95% CI, -0.221 to 0.002), indicated by lower BRIEF-P scores. Those with more minutes of screen time had poorer overall EF (β, 0.257; 95% CI, 0.118-0.384), inhibitory self-control (β, 0.231; 95% CI, 0.099-0.354), cognitive flexibility (β, 0.217; 95% CI, 0.082-0.342), and emergent metacognition (β, 0.257; 95% CI, 0.120-0.381). Daily physical activity was associated with greater emergent metacognition (β, -0.116; 95% CI, -0.225 to -0.005).

CONCLUSIONS

Meeting AAP guidelines for physical activity and screen time was related to greater EF in a demographically homogenous sample of toddlers. Future randomized control trials and more diverse samples are needed to confirm the directionality of this relationship.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT03341858.

Pathways of atopic disease and neurodevelopmental impairment: assessing the evidence for infant antibiotics

INTRODUCTION

Epidemiologic studies are starting to report associations between antibiotic use in early life and neurodevelopmental disorders. Through mechanisms within the gut microbiota-brain axis, indeed, it is plausible that infant antibiotic treatment plays a role in the development of atopic disease and neurodevelopmental disorders.

AREAS COVERED

This narrative review summarizes and interprets published evidence on infant antibiotic use in future outcomes of atopic disease, and neurodevelopmental delay and disorders, including attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). To this end, we critically assess study bias from 2 main confounding factors, maternal/infant infection and infant feeding status. We also discuss common mechanisms that link atopy and neurodevelopment, and propose hypotheses related to immune activation and the gut microbiome.

EXPERT OPINION

Atopic disease and neurodevelopmental disorders share many risk factors and biological pathways. Infant antibiotic use has been linked to both disorders and is likely a marker for prenatal or infant infection. The mediating role of breastfeeding can also not be discounted. The exploration of causal pathways along the gut-brain axis leading towards neurodevelopmental impairment is evolving and of future interest.

Exclusive breastmilk pumping: A concept analysis

Aim

To analyze and examine the concept of exclusive breast pumping (EP).

Background

Breastmilk is the ideal nutrition for infants, yet when breastfeeding is unsuccessful, parents resort to informal breastmilk sharing, artificial formula feeding, or EP. A growing proportion of families exclusively pump yet they often receive guidance from social media rather than healthcare providers because healthcare providers are uninformed about this feeding method.

Data Source

Cumulative Index of Nursing and Allied Health Literature, PubMed, and Google Scholar databases were searched using the following keywords: human milk express*, breast express*, breast milk express, breastmilk express*, exclusive pump, exclusive breast pumping, and exclusive expression.

Review Methods

Concept analysis design using Walker and Avant's method.

Results

Three defining attributes of (1) absence of direct breastfeeding, (2) breastmilk expression, (3) and an enduring infant feeding pattern of feeding expressed breastmilk only via a bottle were identified. All three attributes are required to confirm the presence of the concept of exclusive pumping. Definitions, antecedents, consequences, and empirical referents are described. Model and contrary cases are discussed.

Conclusion

This exclusive pumping concept analysis allows for consistency in terminology in practice and research. EP is a feeding method which can increase the proportion of infants who are fed breastmilk and may reduce the risks that arise from artificial formula feeding.

Exosome-Derived MicroRNAs of Human Milk and Their Effects on Infant Health and Development

Multiple biologically active components of human milk support infant growth, health and development. Milk provides a wide spectrum of mammary epithelial cell-derived extracellular vesicles (MEVs) for the infant. Although the whole spectrum of MEVs appears to be of functional importance for the growing infant, the majority of recent studies report on the MEV subfraction of milk exosomes (MEX) and their miRNA cargo, which are in the focus of this review. MEX and the dominant miRNA-148a play a key role in intestinal maturation, barrier function and suppression of nuclear factor-κB (NF-κB) signaling and may thus be helpful for the prevention and treatment of necrotizing enterocolitis. MEX and their miRNAs reach the systemic circulation and may impact epigenetic programming of various organs including the liver, thymus, brain, pancreatic islets, beige, brown and white adipose tissue as well as bones. Translational evidence indicates that MEX and their miRNAs control the expression of global cellular regulators such as DNA methyltransferase 1-which is important for the up-regulation of developmental genes including insulin, insulin-like growth factor-1, α-synuclein and forkhead box P3-and receptor-interacting protein 140, which is important for the regulation of multiple nuclear receptors. MEX-derived miRNA-148a and miRNA-30b may stimulate the expression of uncoupling protein 1, the key inducer of thermogenesis converting white into beige/brown adipose tissue. MEX have to be considered as signalosomes derived from the maternal lactation genome emitted to promote growth, maturation, immunological and metabolic programming of the offspring. Deeper insights into milk's molecular biology allow the conclusion that infants are both "breast-fed" and "breast-programmed". In this regard, MEX miRNA-deficient artificial formula is not an adequate substitute for breastfeeding, the birthright of all mammals.