Breast milk and cognitive development--the role of confounders: a systematic review

Association between breastfeeding duration and educational attainment in rural Southwest Uganda: a population-based cohort study

BACKGROUND

Breastfeeding is important for early childhood nutrition and health. The positive effects on educational outcomes may be attributed to socioeconomic factors. Socioeconomic status is not a strong predictor of breastfeeding in sub-Saharan African countries. Yet, few studies have investigated the association between breastfeeding and educational outcomes in these countries.

OBJECTIVE

This study investigated the association between breastfeeding duration and children's educational attainment in rural Southwest Uganda.

METHODS

We analysed longitudinal data on 3018 children who had information on breastfeeding and were followed for at least 5 years, with at least one primary school grade recorded by 2005. Data on breastfeeding duration were collected from mothers. The highest school grade was recorded repeatedly between ages 6 and 12 years. We calculated age-for-grade based on whether a child was on, over, or under the official age for a grade. Generalised estimating equations and binary logistic regression estimated the effect of breastfeeding duration on being 2 years, 3 or more years, or any years over-age for grade in primary school, adjusting for socioeconomic status and maternal-child characteristics.

RESULTS

Most mothers breastfed for more than a year. Just over one-third breastfed for 18-23 months, and 30% breastfed for longer. By age eight, 42% of the children were two years over-age for their grade. Three or more years over-age for grade increased from 19% at age nine to 56% at age 12. Both adjusted and unadjusted estimates were consistent in showing reduced odds for children being 2 years, 3 or more years, or any years over-age for grade among children breastfed for 7-12, 13-17, 18-23, and > 23 months compared to those breastfed for 0-6 months. There was no evidence to support an overall association between breastfeeding duration and being over-age for grade. There was no evidence of association in the sex and age sub-group analyses.

CONCLUSION

Although we found no association between breastfeeding duration and educational attainment, breastfeeding remains important for children's health and nutrition, and mothers should be encouraged and supported to breastfeed for the recommended duration.

Social determinants of health and language outcomes in preterm infants with public and private insurance

OBJECTIVE

To evaluate associations of maternal social determinants of health (SDOH) with language outcomes of preterm infants with public and private insurance.

STUDY DESIGN

Single center study of 375 neonates born ≤ 28 weeks. Perinatal characteristics were collected, and the Bayley III was administered at 18-24 months. Primary outcome was language scores of <85. Bivariate and multivariable analyses were used to compare groups.

RESULTS

Mothers with public insurance had higher rates of psychosocial risk factors. In regression analysis, People of Color (aOR 2.4, 1.47-4.04), non-English speaking household (aOR 4.05, 1.47-11.15) and public insurance (aOR 2.03, 1.18-3.49) significantly increased the odds of having a language composite score of <85, whereas breast milk (aOR 0.47, 0.28-0.79) was protective.

CONCLUSIONS

Preterm infants with public insurance are at increased risk of exposure to multiple SDOH which are independently associated with language delay at 18-24 months.

Breastfeeding duration and brain-body development in 9-10-year-olds: modulating effect of socioeconomic levels

OBJECTIVE

To investigate relationships of breastfeeding duration with brain structure and adiposity markers in youth and how these relationships are modified by neighborhood socioeconomic environments (SEEs).

METHODS

This was a cross-sectional study of youth enrolled in the Adolescent Brain and Cognitive Development (ABCD) Study® (n = 7511). Mixed effects models examined associations of breastfeeding duration with global brain measures and adiposity markers, adjusting for sociodemographic, pre- and post-natal covariates. Stratified analysis was performed by area deprivation index (ADI) tertiles.

RESULTS

Total cortical surface area (SA) (False Discovery Rate - FDR corrected P < 0.001), cortical (FDR corrected P < 0.001) and subcortical gray matter (GM) volume (FDR corrected P < 0.001) increased with increased breastfeeding duration. Body mass index (BMI) z-scores (FDR corrected P = 0.001), waist circumference (FDR corrected P = 0.002) and waist-to-height ratio (WHtR) (FDR corrected P = 0.001) decreased with increased breastfeeding duration. Breastfeeding duration was inversely associated with adiposity in youth from high- and medium- ADI neighborhoods, but positively associated with SA across ADI tertiles.

CONCLUSIONS

In this cross-sectional study, longer breastfeeding duration was associated with lower adiposity indices, particularly in youth from lower SEEs and greater SA across SEE levels. Longer breastfeeding duration showed long-term associations with brain and body development for offspring.

IMPACT

Building on previous findings that longer breastfeeding duration is associated with healthier weight gain, lower obesity risk, and brain white matter development in infancy, our results find longer breastfeeding duration to be associated with lower adiposity indices and greater cortical and subcortical gray matter volume, and cortical surface area during peri-adolescence. Children from lower socioeconomic environments (SEEs) demonstrated stronger negative associations of breastfeeding duration and adiposity indices, and children across SEEs showed positive relationships between breastfeeding duration and cortical surface area. Promoting breastfeeding, particularly among women from lower SEEs would confer long-term benefits to offspring.

Evaluating the association between duration of breastfeeding and fine motor development among children aged 20 to 24 months in Butajira, Ethiopia: a case-control study

BACKGROUND

A Suitable environment and proper child nutrition are paramount to a child's physical and mental development. Different environmental factors contribute to proper child development. Breast milk is an important source of nutrition during the early years of life and contains essential nutrients that are the building blocks for growth and development.

OBJECTIVE

To assess the association between the duration of breastfeeding and fine motor development among children aged 20 to 24 months living in Butajira, southern Ethiopia.

METHOD

Community-based case-control study design was employed among mother-child dyads of children aged 20 to 24 months in Butajira Southern Ethiopia. Children were screened for fine motor delay using the Denver II developmental screening and identified as cases and controls. A repeated visit was done to gather the rest of the information and 332 samples, 83 cases, and 249 controls were available and assessed. Epi-data version 4.4.2.1 software was used to prepare a data entry template, which was later exported to and analyzed using STATA version 14 statistical software. Finally, a Multivariable logistic regression model was used to adjust for confounders and estimate the independent effect of breastfeeding duration on fine motor development.

RESULT

We didn't find a significant association between the duration of breastfeeding from 21 to 24 months and fine motor delay compared to children who were breastfed less than 18 months[AOR: 0.86, 95% CI: (0.36, 2.05)]. Children who have mothers > 35 years of age were 78% less likely than children who had mothers younger than 25 years, Children who had mothers in secondary school and above were 77% less likely than mothers who didn't have formal education, Females were 1.86 times more likely than males, and Children who scored 20-29 on the Home score were 51% less likely than Children who scored < 20 to have fine motor delay.

CONCLUSION

Duration of breastfeeding was not significantly associated with fine motor delay for children aged 20 to 24 months old. The age of the mother, the educational status of the mother, being female, and Home score were identified to have a significant association with fine motor delay. Improving the educational status and empowerment of women is essential. Further work should be done on avoiding gender differences starting from a young age and creating a conducive environment for child development is crucial.

Unraveling the effects of maternal breastfeeding duration and exclusive breast milk on children's cognitive abilities in early childhood

Background

This study investigated the putative associations between mothers' use of exclusive breast milk and the duration of breastfeeding with child cognitive development.

Methods

This study is based on 2,210 Canadian families with children assessed longitudinally from age 4 to 7 years on their memory-span and math skills. These cognitive abilities were measured with standardized tasks. Breastfeeding practices were collected via maternal reports. We applied propensity scores to control the social selection bias for breastfeeding.

Results

Results adjusted for propensity scores and sample weight revealed no significant differences between non-breastfed children with those being non-exclusively breastfed for 5 months or less, and with children being exclusively breastfed for 9.2 months on average, on their early math skills and memory-span. We found that children who were non-exclusively breastfed for 6.8 months on average had a slightly higher levels of memory-span at age 4 than children who were never breastfed, and this small but significant difference lasted up to age 7.

Conclusion

Our findings suggest no significant differences between children being exclusively breastfed and those fed with formula on their early math skills and memory-span. The encouragement of breastfeeding to promote child cognitive school readiness may, in some case (non-exclusive breastfeeding for more than 5 months), show a small but long-lasting advantage in early memory-span.

Is breastfeeding duration related to the health of migrant mother-child dyads experiencing homelessness? The ENFAMS cross-sectional survey

BACKGROUND

Literature from the general population shows a consensus about the health benefits associated with breastfeeding for both mothers and children. However, studies investigating these issues in the context of homelessness and migration are rare. This research aimed to examine the relations of any breastfeeding duration with health outcomes among migrant mother-child dyads experiencing homelessness.

METHODS

Data were collected among sheltered and mainly foreign-born mothers experiencing homelessness, and their children aged 6 months to 5 years, from the ENFAMS cross-sectional survey (n = 481, 2013-Great Paris area). Any breastfeeding duration, along with various health outcomes of both the mother and her child, was ascertained by face-to-face questionnaires administered by trained interviewers to mothers (perceived physical and emotional health and maternal depression) or by trained psychologists to children (adaptive behaviours). Nurses measured weight and height [thus allowing them to calculate body mass index (BMI)] and haemoglobin concentration (mother-child dyad) and maternal blood pressure. Multivariable linear and modified Poisson regression analyses were performed to examine outcome-wide associations between any breastfeeding duration ≥6 months and the various mother-child outcomes.

RESULTS

Any breastfeeding ≥6 months was associated with lower systolic blood pressure in mothers (B = -0.40, 95% confidence interval = -0.68 to -0.12). No association was observed with the other outcomes.

CONCLUSIONS

The relevance of supporting breastfeeding to improve mothers' physical health holds true in the context of migration and homelessness. It is therefore important to support breastfeeding in these settings. Moreover, given the documented social complexity of breastfeeding practices, interventions should take mothers' socio-cultural heritage and the structural barriers they face into account.

Effects of exclusive breastfeeding on educational attainment and longitudinal trajectories of grade progression among children in a 13-year follow-up study in Malawi

The benefits of exclusive breastfeeding (EBF) for infant health and survival are well documented. However, its impact on educational outcomes has been contested and poorly researched in Africa. It has been hypothesised that positive associations reported in high-income countries can be attributed to residual confounding by socioeconomic status (SES). Our study investigated whether EBF duration in infancy is associated with educational attainment and age-for-grade attainment trajectories at school-age in rural Malawi. Longitudinal data on 1021 children at the Karonga demographic surveillance site in Malawi were analysed. Breastfeeding data were collected 3 months after birth and again at age one. The school grade of each child was recorded each year from age 6 until age 13. We calculated age-for-grade based on whether a child was at, over, or under the official expected age for a grade. Generalised estimating equations estimated the average effect of breastfeeding on age-for-grade. Latent class growth analysis identified age-for-grade trajectories, and multinomial logistic regression examined their associations with EBF. Maternal-child characteristics, SES, and HIV status were controlled. Overall, 35.9% of the children were exclusively breastfed for 6 months. Over-age for grade steadily increased from 9.6% at age 8 to 41.9% at age 13. There was some evidence that EBF for 6 months was associated with lower odds of being over-age for grade than EBF for less than 3 months (aOR = 0.82, 95%CI = 0.64-1.06). In subgroup analyses, children exclusively breastfed for 6 months in infancy were less likely to be over-age for grades between ages 6-9 (aOR = 0.64, 95%CI = 0.43-0.94). Latent class growth analysis also provided some evidence that EBF reduced the odds of falling behind in the early school grades (aOR = 0.66, 95%CI = 0.41-1.08) but not later. Our study adds to the growing evidence that EBF for 6 months has benefits beyond infant health and survival, supporting the WHO's recommendation on EBF.

Cardiometabolic effects of breastfeeding on infants of diabetic mothers

BACKGROUND

Breast milk is the best and principal nutritional source for neonates and infants. It may protect infants against many metabolic diseases, predominantly obesity and type 2 diabetes. Diabetes mellitus (DM) is a chronic metabolic and microvascular disease that affects all the body systems and all ages from intrauterine life to late adulthood. Breastfeeding protects against infant mortality and diseases, such as necrotizing enterocolitis, diarrhoea, respiratory infections, viral and bacterial infection, eczema, allergic rhinitis, asthma, food allergies, malocclusion, dental caries, Crohn's disease, and ulcerative colitis. It also protects against obesity and insulin resistance and increases intelligence and mental development. Gestational diabetes has short and long-term impacts on infants of diabetic mothers (IDM). Breast milk composition changes in mothers with gestational diabetes.

AIM

To investigate the beneficial or detrimental effects of breastfeeding on the cardiometabolic health of IDM and their mothers.

METHODS

We performed a database search on different engines and a thorough literature review and included 121 research published in English between January 2000 and December 15, 2022, in this review.

RESULTS

Most of the literature agreed on the beneficial effects of breast milk for both the mother and the infant in the short and long terms. Breastfeeding protects mothers with gestational diabetes against obesity and type 2 DM. Despite some evidence of the protective effects of breastfeeding on IDM in the short and long term, the evidence is not strong enough due to the presence of many confounding factors and a lack of sufficient studies.

CONCLUSION

We need more comprehensive research to prove these effects. Despite many obstacles that may enface mothers with gestational diabetes to start and maintain breastfeeding, every effort should be made to encourage them to breastfeed.

The influence of nutrition on white matter development in preterm infants: a scoping review

White matter (WM) injury is the most common type of brain injury in preterm infants and is associated with impaired neurodevelopmental outcome (NDO). Currently, there are no treatments for WM injury, but optimal nutrition during early preterm life may support WM development. The main aim of this scoping review was to assess the influence of early postnatal nutrition on WM development in preterm infants. Searches were performed in PubMed, EMBASE, and COCHRANE on September 2022. Inclusion criteria were assessment of preterm infants, nutritional intake before 1 month corrected age, and WM outcome. Methods were congruent with the PRISMA-ScR checklist. Thirty-two articles were included. Negative associations were found between longer parenteral feeding duration and WM development, although likely confounded by illness. Positive associations between macronutrient, energy, and human milk intake and WM development were common, especially when fed enterally. Results on fatty acid and glutamine supplementation remained inconclusive. Significant associations were most often detected at the microstructural level using diffusion magnetic resonance imaging. Optimizing postnatal nutrition can positively influence WM development and subsequent NDO in preterm infants, but more controlled intervention studies using quantitative neuroimaging are needed. IMPACT: White matter brain injury is common in preterm infants and associated with impaired neurodevelopmental outcome. Optimizing postnatal nutrition can positively influence white matter development and subsequent neurodevelopmental outcome in preterm infants. More studies are needed, using quantitative neuroimaging techniques and interventional designs controlling for confounders, to define optimal nutritional intakes in preterm infants.

Prenatal Exposure to Tobacco and Childhood Cognition and Behavior: Effect Modification by Maternal Folate Intake and Breastfeeding Duration

In this exploratory analysis, we assessed whether nutrition modified the association between prenatal exposure to tobacco and childhood cognition/behavior among 366 Colorado-based mothers and their offspring (born ≥ 37 weeks with birthweights ≥ 2500 g). Interaction by folate ( 5 months, but not for shorter durations. Our findings support the need for smoking cessation campaigns throughout pregnancy and throughout the postpartum period breastfeeding to reduce neurobehavioral risks in the offspring.

Breastfeeding is not a risk factor for clinical severity in Autism spectrum disorder in children from the ELENA cohort

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that results from a complex interaction between genes and environment. Breastfeeding (BF) is thought to promote healthy cognitive development, and a body of research has suggested that it may also protect against ASD. Our objectives were to identify the relationship between the initiation and duration of BF and the severity of clinical presentation in ASD. Data were collected from 243 children with a confirmed diagnosis of ASD followed in the ELENA cohort. Clinical severity was measured according to multiple dimensions using standardised tools. The frequency of the initiation of BF was comparable to that of the general population and the rate of children still being breastfed at six months of age was higher. Our results did not indicate a contribution of initiation or duration of BF to the prevention of clinical severity of ASD. We discuss our results in the light of possible methodological limitations of previous reports of an association between BF and ASD.Clinical Trial Registration: NCT02625116.

Long-term benefits of breastfeeding on brain and body development among 9-10-year-olds: modulated by socioeconomic environment

Importance

It is yet unknown if breastfeeding (bf) benefits, to brain and body development of children, persist into peri-adolescence and vary by socioeconomic environments (SEEs).

Objective

We aim to investigate SEE-independent and SEE-modulated relationships between bf duration and child brain structure and adiposity markers during peri-adolescence.

Design setting and participants

This was a cross-sectional study of children aged 9-10 enrolled in the multi-center Adolescent Brain and Cognitive Development (ABCD) Study®.

Exposures

Bf duration was self-reported. Neighborhood-level SEE was assessed using area deprivation index (ADI).

Main Outcomes

T1-weighted magnetic resonance imaging was used to assess global brain measures: volumes of white, cortical, and subcortical gray matter (GM), cortical thickness, and surface area (SA). Adiposity markers included age- and sex-specific body mass index (BMI z- scores), waist circumference, and waist-to-height ratio (WHtR). Mixed effects models examined associations of bf duration with brain structure and adiposity markers controlling for sociodemographic, pre- and post-natal covariates. Stratified analysis was performed by tertiles of ADI.

Results

The sample consisted of 7,511 children (51.7% males; 18.8% no bf, 35.3% 1-6 months, 24.9% 7-12 months, 21.0% >12 months). Child's total SA (β (95% CI) = 0.053 (0.033, 0.074); FDR corrected P <0.001), cortical (β (95% CI) = 0.021 (0.010, 0.032); FDR corrected P <0.001) and subcortical GM volume (β (95% CI) = 0.016 (0.003, 0.030); FDR corrected P <0.001) increased monotonically with bf duration, after controlling for covariates. Child's BMI z -scores (β (95% CI) = -0.040 (-0.063, -0.016); FDR corrected P =0.001), waist circumference (β (95% CI) = -0.037 (-0.060, -0.014), FDR corrected P =0.002) and WHtR (β (95% CI) = -0.040 (-0.064, -0.018), FDR corrected P =0.001) decreased monotonically with increased bf duration, after controlling for covariates. Bf duration was inversely associated with adiposity in children from high- and medium-ADI neighborhoods. Bf duration was positively associated with SA across ADI tertiles.

Conclusions and Relevance

Our results imply that long-term benefits of bf on body and brain development in offspring increase as bf duration increases, particularly in children from low SEEs. Policies and social support aimed to incremental increases in bf duration among women from low SEEs would confer long-term benefits for offspring.

Key Points

Question: Do benefits of breastfeeding(bf), on children's brain and body development, persist long-term and are these benefits uniform across socioeconomic environments (SEEs)?Findings: Longer bf duration is associated with lower adiposity, greater cortical and subcortical gray matter volume, and cortical surface area in 9-10-year-old children. Children from lower SEEs showed stronger negative relationships between bf duration and adiposity. Children across all SEEs demonstrated positive relationships between bf duration and surface area.Meaning: Our results imply that long-term benefits to child brain and body development increase with bf duration; and children from lower SEEs benefited more from longer bf duration.

Human milk microbial species are associated with infant head-circumference during early and late lactation in Guatemalan mother-infant dyads

Human milk contains abundant commensal bacteria that colonize and establish the infant's gut microbiome but the association between the milk microbiome and head circumference during infancy has not been explored. For this cross-sectional study, head-circumference-for-age-z-scores (HCAZ) of vaginally delivered breastfed infants were collected from 62 unrelated Mam-Mayan mothers living in eight remote rural communities in the Western Highlands of Guatemala during two stages of lactation, 'early' (6-46 days postpartum, n = 29) or 'late' (109-184 days postpartum, n = 33). At each stage of lactation, infants were divided into HCAZ ≥ -1 SD (early: n = 18; late: n = 14) and HCAZ < -1 SD (early: n = 11; late: n = 19). Milk microbiome communities were assessed using 16S ribosomal RNA gene sequencing and DESeq2 was used to compare the differential abundance (DA) of human milk microbiota with infant HCAZ subgroups at both stages of lactations. A total of 503 ESVs annotated 256 putative species across the 64 human milk samples. Alpha-diversity using Chao index uncovered a difference in microbial community richness between HCAZ ≥ -1 SD and HCAZ < -1 SD groups at late lactation (p = 0.045) but not at early lactation. In contrast, Canonical Analysis of Principal Coordinates identified significant differences between HCAZ ≥ -1 SD and HCAZ < -1 SD at both stages of lactation (p = 0.003); moreover, 26 milk microbial taxa differed in relative abundance (FDR < 0.05) between HCAZ ≥ -1 SD and HCAZ < -1 SD, with 13 differentially abundant at each lactation stage. Most species in the HCAZ ≥ -1 SD group were Streptococcus species from the Firmicutes phylum which are considered human colonizers associated with human milk whereas the HCAZ < -1 SD group at late lactation had more differentially abundant taxa associated with environmentally and 'potentially opportunistic' species belonging to the Actinobacteria genus. These findings suggest possible associations between brain growth of breastfed infants and the milk microbiome during lactation. Importantly, these data provide the first evidence of cross talk between the human milk microbiome and the infant brain that requires further investigation.

Associations between sociodemographic and behavioural parameters and child development depending on age and sex: a cross-sectional analysis

OBJECTIVES

To explore environmental and individual factors that are associated with child development and to investigate whether the strength of these associations differs according to the age of the children.

DESIGN

Cross-sectional study.

SETTING

This study was part of the LIFE Child study, a large cohort study conducted in Leipzig, Germany.

PARTICIPANTS

778 children aged between 0.5 and 6 years (48.6% girls, mean age=2.67 years).

OUTCOME MEASURES

The outcomes were cognitive development, language development, body and hand motor skills, social-emotional development, and tracing skills, measured with a standardised development test. We analysed the associations between development and gestational age, socioeconomic status (SES), sex, behavioural difficulties, siblings, sleep duration, breastfeeding duration and overweight/obesity. We also tested for interactions between these variables and child age or sex.

RESULTS

Higher gestational age (b ranging between 0.12 and 0.26) and higher SES (b ranging between 0.08 and 0.21) were associated with better outcomes in almost all developmental domains (all p<0.019). Children with older siblings had improved body and hand motor skills compared with children without older siblings (both b=0.55, all p<0.029). Boys had poorer scores than girls in body and hand motor skills and tracing (b=-0.45, -0.68 and -1.5, all p<0.019). Children with behavioural difficulties had significantly poorer outcomes in most developmental domains. Some of the associations with SES and sex were stronger in older than in younger children. Associations between gestational age and motor development were weaker in older children. We did not find significant associations between child development and sleep duration, breastfeeding duration or overweight/obesity.

CONCLUSION

Some factors had a protective, others an adverse effect on development of children under 6 years of age. The effect of SES and sex increased, while the effect of gestational age decreased with age.

TRIAL REGISTRATION NUMBER

NCT02550236.

The association of breastfeeding with cognitive development and educational achievement in sub-Saharan Africa: A systematic review

Background

Systematic reviews and meta-analyses of studies mainly from high-income countries suggest that breastfeeding improves cognitive function and educational achievement. However, these associations may be a manifestation of who breastfeeds in these settings rather than an actual effect of breastfeeding. We investigated the association of breastfeeding with cognitive development and educational achievements in sub-Saharan Africa, where breastfeeding is the norm, and socioeconomic status is not strongly correlated with ever breastfeeding.

Methods

We searched Medline, Embase, PsycINFO, Cochrane Central Register of Controlled Trials (CENTRAL), and Africa-Wide Information in January 2021 for studies that assessed the cognitive and educational benefits of breastfeeding in children and adolescents in sub-Saharan Africa. Two reviewers independently screened, extracted, and critically appraised the included studies.

Results

After reviewing 5552 abstracts and 151 full-text articles, seventeen studies on cognitive development and two on educational achievements met our predefined inclusion criteria. The included studies were from ten sub-Saharan African countries and published between 2013 and 2021, with sample sizes ranging from 54 to 6573. Most of the studies (n = 14) were prospective cohort studies, but only nine collected data on breastfeeding prospectively. The studies differed in analytic approaches and cognitive and educational achievements measurements. Of the 17 studies on cognitive development, only four adjusted sufficiently for key confounders. None of these four studies found an overall association between breastfeeding and cognitive development in children or adolescents in sub-Saharan Africa. The two studies on education measured achievements based on the highest grade of school attained, 12 or more years of education, or grade repetition at age 7-11 years. Both studies adjusted for a range of sociodemographic factors and found no evidence that children exclusively breastfed or breastfed for a longer duration have a better educational outcome than sub-optimally breastfed children.

Conclusions

The current evidence from sub-Saharan Africa is limited but does not corroborate previous findings that breastfeeding is associated with improved cognitive development and educational achievement.

Registration

This study is registered with PROSPERO, CRD42021236009.

Profiles of Functioning in 5.5-Year-Old Very Preterm Born Children in France: The EPIPAGE-2 Study

OBJECTIVE

Very preterm born children are at risk for impairments in multiple neurodevelopmental domains, but outcomes vary between individuals. The present study aimed to distinguish subgroups with distinct profiles of functioning across motor, cognitive, behavioral, and psychosocial domains. These profiles were related to neonatal and social/environmental factors.

METHOD

The sample included 1977 children born very preterm (<32 weeks' gestation) in 2011 from the French population-based EPIPAGE-2 cohort. Using latent profile analysis, subgroups of children were distinguished based on their functioning at 5.5 years. The relation between outcome profiles and neonatal and social/environmental factors was tested using multivariable multinomial logistic regression analysis.

RESULTS

Four subgroups with distinct outcome profiles were distinguished: no deficit in any domain (45%); motor and cognitive deficits without behavioral/psychosocial deficits (31%); primarily behavioral and psychosocial deficits (16%); and deficits in multiple domains (8%). Male sex (odds ratio [OR] = 2.1-2.7), bronchopulmonary dysplasia (OR = 2.1-2.8), low parental education level (OR = 1.8-2.1), and parental non-European immigrant status (OR = 2.3-3.0) were independently associated with higher odds for all suboptimal outcome profiles compared to the favorable outcome profile.

CONCLUSION

Among 5.5-year-old very preterm born children, subgroups can be distinguished with distinct outcome profiles that vary in severity, type, and combinations of deficits. This information is important for the development of interventions that are tailored to the needs of large subgroups of children across multiple domains of functioning. General neonatal and social/environmental factors may be useful for early identification of very preterm born children at risk for general rather than domain-specific impairments.

To what extent does confounding explain the association between breastfeeding duration and cognitive development up to age 14? Findings from the UK Millennium Cohort Study

Background

Breastfeeding duration is associated with improved cognitive development in children, but it is unclear whether this is a causal relationship or due to confounding. This study evaluates whether the observed association is explained by socioeconomic position (SEP) and maternal cognitive ability.

Methods

Data from 7,855 singletons born in 2000–2002 and followed up to age 14 years within the UK Millennium Cohort Study were analysed. Mothers reported breastfeeding duration, and children’s cognitive abilities were assessed at 5, 7, 11, and 14 years using validated measures. Standardised verbal (age 5 to 14) and spatial (age 5 to 11) cognitive scores were compared across breastfeeding duration groups using multivariable linear mixed-effects models (repeated outcome measures).

Results

At all ages, longer breastfeeding durations were associated with higher cognitive scores after accounting for the child’s own characteristics. Adjustment for SEP approximately halved the effect sizes. Further adjustment for maternal cognitive scores removed the remaining associations at age 5, but not at ages 7, 11 and 14 (e.g.: verbal scores, age 14; breastfed ≥12 months vs never breastfed: 0.26 SD; 95%CI: 0.18, 0.34).

Conclusion

The associations between breastfeeding duration and cognitive scores persist after adjusting for SEP and maternal cognitive ability, however the effect was modest.

Human milk microbiota: what did we learn in the last 20 years?

Human milk (HM) is the gold standard for infant nutrition during the first months of life. Beyond its nutritional components, its complex bioactive composition includes microorganisms, their metabolites, and oligosaccharides, which also contribute to gut colonization and immune system maturation. There is growing evidence of the beneficial effects of bacteria present in HM. However, current research presents limited data on the presence and functions of other organisms. The potential biological impacts on maternal and infant health outcomes, the factors contributing to milk microbes' variations, and the potential functions in the infant's gut remain unclear. This review provides a global overview of milk microbiota, what the actual knowledge is, and what the gaps and challenges are for the next years.

Early Life Exposure to a Diet With a Supramolecular Lipid Structure Close to That of Mammalian Milk Improves Early Life Growth, Skeletal Development, and Later Life Neurocognitive Function in Individually and Socially Housed Male C57BL/6J Mice

Breastfeeding (duration) can be positively associated with infant growth outcomes as well as improved cognitive functions during childhood and later life stages. (Prolonged) exposure to optimal lipid quantity and quality, i.e., the supramolecular structure of lipids, in mammalian milk, may contribute to these beneficial effects through nutritional early-life programming. In this pre-clinical study, we exposed male C57BL/6J mice from post-natal Days 16 to 42 (i.e., directly following normal lactation), to a diet with large lipid droplets coated with bovine milk fat globule membrane-derived phospholipids, which mimic more closely the supramolecular structure of lipid droplets in mammalian milk. We investigated whether exposure to this diet could affect growth and brain development-related parameters. As these outcomes are also known to be affected by the post-weaning social environment in mice, we included both individually housed and pair-wise housed animals and studied whether effects of diet were modulated by the social environment. After Day 42, all the animals were fed standard semi-synthetic rodent diet. Growth and body composition were assessed, and the mice were subjected to various behavioral tests. Individual housing attenuated adolescent growth, reduced femur length, and increased body fat mass. Adult social interest was increased due to individual housing, while cognitive and behavioral alterations as a result of different housing conditions were modest. The diet increased adolescent growth and femur length, increased lean body mass, reduced adolescent anxiety, and improved adult cognitive performance. These effects of diet exposure were comparable between individually and socially housed mice. Hence, early life exposure to a diet with lipid droplets that mimic the supramolecular structure of those in mammalian milk may improve adolescent growth and alters brain function in both socially and individually housed mice. These findings suggest that lipid structure in infant milk formula may be a relevant target for nutritional solutions, targeting both healthy infants and infants facing growth challenges.

A multi-center longitudinal study on responsive breastfeeding in China from the perspective of health equity: research protocol

Background

Socio-economic inequities can strongly influence suboptimal infant feeding outcomes. Factors such as lack of knowledge about breastfeeding, low family income, low educational attainment, social and economic status, cultural norms and ethnicity may negatively affect success with offering breastfeeding following a responsive feeding approach (ie. responsive breastfeeding). Such inequities can indeed shorten breastfeeding duration, and negatively affect behavioral and cognitive infant outcomes. In China, there is a dearth of studies focusing on breastfeeding from the responsive and health equity perspective.

Objective

The aim of this article is to present a protocol of an ongoing longitudinal cohort study investigating factors associated with responsive breastfeeding behaviors, and the child’s behavioral and cognitive development from birth to12 months post-partum in five centers in China. The study seeks to identify breastfeeding barriers and facilitators from a health equity perspective.

Methods

We are enrolling 700 women and their singleton full term infants in Chongqing, Huizhou and Guangzhou urban and rural areas. The study questionnaires will be administrated within 72 h, 30 days, 3, 6, 9, and 12 months post-partum during the baby’s vaccination visits. We will investigate the difference between urban and rural areas sociodemographic characteristics, breastfeeding knowledge, attitudes and practice, postnatal depression, maternal emotion regulation and parenting stress, and anthropometric and cognitive development indicators of the infants at each time-point.

Conclusion

Our article illustrates how a cohort study can be designed to understand the barriers and facilitators of responsive breastfeeding taking equity principles into account to help promote infants’ growth and development in China.

Breastfeeding Duration Is Associated With Domain-Specific Improvements in Cognitive Performance in 9-10-Year-Old Children

Significant immunological, physical and neurological benefits of breastfeeding in infancy are well-established, but to what extent these gains persist into later childhood remain uncertain. This study examines the association between breastfeeding duration and subsequent domain-specific cognitive performance in a diverse sample of 9-10-year-olds enrolled in the Adolescent Brain Cognitive Development (ABCD) Study®. The analyses included 9,116 children that attended baseline with their biological mother and had complete neurocognitive and breastfeeding data. Principal component analysis was conducted on data from an extensive battery of neurocognitive tests using varimax-rotation to extract a three-component model encompassing General Ability, Executive Functioning, and Memory. Propensity score weighting using generalized boosted modeling was applied to balance the distribution of observed covariates for children breastfed for 0, 1-6, 7-12, and more than 12 months. Propensity score-adjusted linear regression models revealed significant association between breastfeeding duration and performance on neurocognitive tests representing General Ability, but no evidence of a strong association with Executive Function or Memory. Benefits on General Ability ranged from a 0.109 (1-6 months) to 0.301 (>12 months) standardized beta coefficient difference compared to those not breastfed. Results indicate clear cognitive benefits of breastfeeding but that these do not generalize to all measured domains, with implications for public health policy as it pertains to nutrition during infancy.

Association between breastfeeding during infancy and white matter microstructure in early childhood

INTRODUCTION

Associations between breastfeeding and brain development, in the context of child, perinatal, and sociodemographic variables, remain unclear. This study investigated whether exclusive breastfeeding for the first 6 months and total duration of breastfeeding were associated with brain white matter microstructure in young children.

METHODS

This study included 85 typically developing children (42 males) born to 83 mothers that were predominantly white, highly educated, and in high income households. Children underwent their first diffusion tensor imaging scan between ages 2.34 and 6.97 years; some children returned multiple times, providing a total of 331 datasets. Feeding information was collected from mothers at 3, 6, and 12 months postpartum and at their child's scan to calculate breastfeeding status at 6 months (exclusive or not) as well as total duration of any breastfeeding. Linear regression was used to investigate associations between breastfeeding exclusivity/duration and fractional anisotropy (FA) for the whole brain and 10 individual white matter tracts.

RESULTS

Breastfeeding exclusivity and duration were associated with global and regional white matter microstructure, even after controlling for perinatal and sociodemographic factors. Greater exclusivity was associated with higher FA in females and lower FA in males.

CONCLUSIONS

These findings suggest white matter differences associated with breastfeeding that differ by sex. These may stem from different trajectories in white matter development between males and females in early childhood and suggest possible long-term white matter differences associated with breastfeeding.

Dairy-Derived Emulsifiers in Infant Formula Show Marginal Effects on the Plasma Lipid Profile and Brain Structure in Preterm Piglets Relative to Soy Lecithin

Breastfed infants have higher intestinal lipid absorption and neurodevelopmental outcomes compared to formula-fed infants, which may relate to a different surface layer structure of fat globules in infant formula. This study investigated if dairy-derived emulsifiers increased lipid absorption and neurodevelopment relative to soy lecithin in newborn preterm piglets. Piglets received a formula diet containing soy lecithin (SL) or whey protein concentrate enriched in extracellular vesicles (WPC-A-EV) or phospholipids (WPC-PL) for 19 days. Both WPC-A-EV and WPC-PL emulsions, but not the intact diets, increased in vitro lipolysis compared to SL. The main differences of plasma lipidomics analysis were increased levels of some sphingolipids, and lipid molecules with odd-chain (17:1, 19:1, 19:3) as well as mono- and polyunsaturated fatty acyl chains (16:1, 20:1, 20:3) in the WPC-A-EV and WPC-PL groups and increased 18:2 fatty acyls in the SL group. Indirect monitoring of intestinal triacylglycerol absorption showed no differences between groups. Diffusor tensor imaging measurements of mean diffusivity in the hippocampus were lower for WPC-A-EV and WPC-PL groups compared to SL indicating improved hippocampal maturation. No differences in hippocampal lipid composition or short-term memory were observed between groups. In conclusion, emulsification of fat globules in infant formula with dairy-derived emulsifiers altered the plasma lipid profile and hippocampal tissue diffusivity but had limited effects on other absorptive and learning abilities relative to SL in preterm piglets.

Perinatal and childhood predictors of general cognitive outcome at 28 years in a very-low-birthweight national cohort

AIM

To determine IQ at 26 to 30 years in very-low-birthweight (VLBW) adults compared with term-born controls; and to examine the stability of IQ in VLBW individuals between 7 to 8 years and 26 to 30 years, identify perinatal and social predictors of IQ, and assess the contribution of brain volume to IQ.

METHOD

At 26 to 30 years, 229 VLBW adults (71% survivors of prospectively enrolled national cohort) and 100 term-born controls were tested on the Wechsler Abbreviated Scale of Intelligence. For VLBW, IQ at 7 to 8 years, perinatal and social data were extracted from the data set, and 150 adults underwent volumetric cranial magnetic resonance imaging (MRI).

RESULTS

At 26 to 30 years, the mean adjusted difference between VLBW and controls for total IQ was 9.4 (95% CI 6.5-12.4) points. In VLBW individuals the correlation between IQ scores at 7 to 8 years and 26 to 30 years was 0.78. On multiple regression analysis, parental education was the strongest predictor of verbal and total IQ at both ages. Birthweight was a strong predictor of perceptual and total IQ. In VLBW individuals with MRI scans, the addition of brain volume as a variable increased the variance explained for perceptual and total IQ.

INTERPRETATION

VLBW adults have mean IQ scores 9 to 11 points below controls. Parental education and birthweight are the strongest predictors of IQ.

Breastfeeding for 3 Months or Longer but Not Probiotics Is Associated with Reduced Risk for Inattention/Hyperactivity and Conduct Problems in Very-Low-Birth-Weight Children at Early Primary School Age

(1) Background: We aimed to evaluate the effect of proposed “microbiome-stabilising interventions”, i.e., breastfeeding for ≥3 months and prophylactic use of Lactobacillus acidophilus/ Bifidobacterium infantis probiotics on neurocognitive and behavioral outcomes of very-low-birthweight (VLBW) children aged 5–6 years. (2) Methods: We performed a 5-year-follow-up assessment including a strength and difficulties questionnaire (SDQ) and an intelligence quotient (IQ) assessment using the Wechsler Preschool and Primary Scale of Intelligence (WPPSI)-III test in preterm children previously enrolled in the German Neonatal Network (GNN). The analysis was restricted to children exposed to antenatal corticosteroids and postnatal antibiotics. (3) Results: 2467 primary school-aged children fulfilled the inclusion criteria. In multivariable linear regression models breastfeeding ≥3 months was associated with lower conduct disorders (B (95% confidence intervals (CI)): −0.25 (−0.47 to −0.03)) and inattention/hyperactivity (−0.46 (−0.81 to −0.10)) as measured by SDQ. Probiotic treatment during the neonatal period had no effect on SDQ scores or intelligence. (4) Conclusions: Prolonged breastfeeding of highly vulnerable infants may promote their mental health later in childhood, particularly by reducing risk for inattention/hyperactivity and conduct disorders. Future studies need to disentangle the underlying mechanisms during a critical time frame of development.

Nutrition and the ageing brain: Moving towards clinical applications

The global increases in life expectancy and population have resulted in a growing ageing population and with it a growing number of people living with age-related neurodegenerative conditions and dementia, shifting focus towards methods of prevention, with lifestyle approaches such as nutrition representing a promising avenue for further development. This overview summarises the main themes discussed during the 3^rd Symposium on "Nutrition for the Ageing Brain: Moving Towards Clinical Applications" held in Madrid in August 2018, enlarged with the current state of knowledge on how nutrition influences healthy ageing and gives recommendations regarding how the critical field of nutrition and neurodegeneration research should move forward into the future. Specific nutrients are discussed as well as the impact of multi-nutrient and whole diet approaches, showing particular promise to combatting the growing burden of age-related cognitive decline. The emergence of new avenues for exploring the role of diet in healthy ageing, such as the impact of the gut microbiome and development of new techniques (imaging measures of brain metabolism, metabolomics, biomarkers) are enabling researchers to approach finding answers to these questions. But the translation of these findings into clinical and public health contexts remains an obstacle due to significant shortcomings in nutrition research or pressure on the scientific community to communicate recommendations to the general public in a convincing and accessible way. Some promising programs exist but further investigation to improve our understanding of the mechanisms by which nutrition can improve brain health across the human lifespan is still required.

Maternal Programming of Social Dominance via Milk Cytokines

Regular physical activity improves physical and mental health. Here we found that the effect of physical activity extends to the next generation. Voluntary wheel running of dams, from postpartum day 2 to weaning, increased the social dominance and reproductive success, but not the physical/metabolic health, of their otherwise sedentary offspring. The individual's own physical activity did not improve dominance status. Maternal exercise did not disrupt maternal care or the maternal and offspring microbiota. Rather, the development of dominance behavior in the offspring of running mothers could be explained by the reduction of LIF, CXCL1, and CXCL2 cytokines in breast milk. These data reveal a cytokine-mediated lactocrine pathway that responds to the mother's postpartum physical activity and programs offspring social dominance. As dominance behaviors are highly relevant to the individual's survival and reproduction, lactocrine programming could be an evolutionary mechanism by which a mother promotes the social rank of her offspring.

A Comparison of Vitamin and Lutein Concentrations in Breast Milk from Four Asian Countries

Vitamins are the essential elements for human life and, particularly, for infant health. Human milk is the best source of nutrients for newborns, however, the information of vitamins in Asian maternal milk is still limited. In this study, we have collected 580 Asian maternal milk samples from Korea (n = 254), China (n = 137), Pakistan (n = 92), and Vietnam (n = 97). The vitamin concentrations, including vitamin B-groups (8 vitamins), fat-soluble vitamin (retinol, D, E, K) and lutein in the breast milk of were investigated. The concentration of thiamin (B1), biotin (B7), and folic acid (B9) in mother's milk of four countries were not considerably different, while riboflavin (B2), pantothenic acid (B5), and pyridoxine (B6) level in Vietnam samples were significantly lower than those in other countries. In contrast, retinol (A) and tocopherol (E) were found to be higher levels in Vietnamese maternal milk. Korean and Chinese maternal milk had low concentrations of retinol that may cause vitamin A deficiency in children. However, Chinese mother's milk was distinguished with a high concentration of lutein. Pakistani mother's milk was observed as having a significant problem of folic acid (B9) deficiency. Regardless of the country, vitamin B12, K, and D did not seem to be provided sufficiently through maternal milk. The moderate positive correlations were found between vitamin concentrations in each country and the pooled sample. The data obtained in this study were able to provide vital information to assess the nutritional status of breast milk in Asian countries and contributed to the efforts of ensuring the best nutrition for Asian children.

Late weaning and maternal closeness, associated with advanced motor and visual maturation, reinforce autonomy in healthy, 2-year-old children

We studied neurodevelopmental outcomes and behaviours in healthy 2-year old children (N = 1306) from Brazil, India, Italy, Kenya and the UK participating in the INTERGROWTH-21^st Project. There was a positive independent relationship of duration of exclusive breastfeeding (EBF) and age at weaning with gross motor development, vision and autonomic physical activities, most evident if children were exclusively breastfed for ≥7 months or weaned at ≥7 months. There was no association with cognition, language or behaviour. Children exclusively breastfed from birth to <5 months or weaned at >6 months had, in a dose-effect pattern, adjusting for confounding factors, higher scores for "emotional reactivity". The positive effect of EBF and age at weaning on gross motor, running and climbing scores was strongest among children with the highest scores in maternal closeness proxy indicators. EBF, late weaning and maternal closeness, associated with advanced motor and vision maturation, independently influence autonomous behaviours in healthy children.

Effect modification of FADS2 polymorphisms on the association between breastfeeding and intelligence: results from a collaborative meta-analysis

Background

Accumulating evidence suggests that breastfeeding benefits children’s intelligence, possibly due to long-chain polyunsaturated fatty acids (LC-PUFAs) present in breast milk. Under a nutritional adequacy hypothesis, an interaction between breastfeeding and genetic variants associated with endogenous LC-PUFAs synthesis might be expected. However, the literature on this topic is controversial.

Methods

We investigated this gene × environment interaction through a collaborative effort. The primary analysis involved >12 000 individuals and used ever breastfeeding, FADS2 polymorphisms rs174575 and rs1535 coded assuming a recessive effect of the G allele, and intelligence quotient (IQ) in Z scores.

Results

There was no strong evidence of interaction, with pooled covariate-adjusted interaction coefficients (i.e. difference between genetic groups of the difference in IQ Z scores comparing ever with never breastfed individuals) of 0.12[(95% confidence interval (CI): −0.19; 0.43] and 0.06 (95% CI: −0.16; 0.27) for the rs174575 and rs1535 variants, respectively. Secondary analyses corroborated these results. In studies with ≥5.85 and <5.85 months of breastfeeding duration, pooled estimates for the rs174575 variant were 0.50 (95% CI: −0.06; 1.06) and 0.14 (95% CI: −0.10; 0.38), respectively, and 0.27 (95% CI: −0.28; 0.82) and −0.01 (95% CI: −0.19; 0.16) for the rs1535 variant.

Conclusions

Our findings did not support an interaction between ever breastfeeding and FADS2 polymorphisms. However, subgroup analysis suggested that breastfeeding may supply LC-PUFAs requirements for cognitive development if breastfeeding lasts for some (currently unknown) time. Future studies in large individual-level datasets would allow properly powered subgroup analyses and further improve our understanding on the breastfeeding × FADS2 interaction.

Fluoride exposure from infant formula and child IQ in a Canadian birth cohort

BACKGROUND

Infant consumption of formula reconstituted with fluoridated water can lead to excessive fluoride intake. We examined the association between fluoride exposure in infancy and intellectual ability in children who lived in fluoridated or non-fluoridated cities in Canada.

METHODS

We examined 398 mother-child dyads in the Maternal-Infant Research on Environmental Chemicals cohort who reported drinking tap water. We estimated water fluoride concentration using municipal water reports. We used linear regression to analyze the association between fluoride exposure and IQ scores, measured by the Wechsler Primary and Preschool Scale of Intelligence-III at 3-4 years. We examined whether feeding status (breast-fed versus formula-fed) modified the impact of water fluoride and if fluoride exposure during fetal development attenuated this effect. A second model estimated the association between fluoride intake from formula and child IQ.

RESULTS

Thirty-eight percent of mother-child dyads lived in fluoridated communities. An increase of 0.5 mg/L in water fluoride concentration (approximately equaling the difference between fluoridated and non-fluoridated regions) corresponded to a 9.3- and 6.2-point decrement in Performance IQ among formula-fed (95% CI: -13.77, -4.76) and breast-fed children (95% CI: -10.45, -1.94). The association between water fluoride concentration and Performance IQ remained significant after controlling for fetal fluoride exposure among formula-fed (B = -7.93, 95% CI: -12.84, -3.01) and breastfed children (B = -6.30, 95% CI: -10.92, -1.68). A 0.5 mg increase in fluoride intake from infant formula corresponded to an 8.8-point decrement in Performance IQ (95% CI: -14.18, -3.34) and this association remained significant after controlling for fetal fluoride exposure (B = -7.62, 95% CI: -13.64, -1.60).

CONCLUSIONS

Exposure to increasing levels of fluoride in tap water was associated with diminished non-verbal intellectual abilities; the effect was more pronounced among formula-fed children.

Association of infant and young child feeding practices with cognitive development at 10–12 years: a birth cohort in rural Western China

We aimed to comprehensively examine the association of breast-feeding, types and initial timing of complementary foods with adolescent cognitive development in low- and middle-income countries. We conducted a prospective cohort study of 745 adolescents aged 10–12 years who were born to women who participated in a randomised trial of prenatal micronutrient supplementation in rural Western China. An infant feeding index was constructed based on the current WHO recommendations. Full-scale intelligence quotient (FSIQ) was assessed and derived by the fourth edition of the Wechsler Intelligence Scale for Children. The duration of exclusive or any breast-feeding was not significantly associated with adolescent cognitive development. Participants who regularly consumed Fe-rich or Fe-fortified foods during 6–23 months of age had higher FSIQ than those who did not (adjusted mean differences 4·25; 95 % CI 1·99, 6·51). For cows’/goats’ milk and high protein-based food, the highest FSIQ was found in participants who initially consumed at 10–12 and 7–9 months, respectively. A strong dose–response relationship of the composite infant feeding index was also identified, with participants in the highest tertile of overall feeding quality having 3·03 (95 % CI 1·37, 4·70) points higher FSIQ than those in the lowest tertile. These findings suggest that appropriate infant feeding practices (breast-feeding plus timely introduction of appropriate complementary foods) were associated with significantly improved early adolescent cognitive development scores in rural China. In addition, improvement in Fe-rich or Fe-fortified foods complementary feeding may produce better adolescent cognitive development outcomes.

Protective Effect of Breastfeeding on the Adverse Health Effects Induced by Air Pollution: Current Evidence and Possible Mechanisms

Air pollution is a major social, economic, and health problem around the world. Children are particularly susceptible to the negative effects of air pollution due to their immaturity and excessive growth and development. The aims of this narrative review were to: (1) summarize evidence about the protective effects of breastfeeding on the adverse health effects of air pollution exposure, (2) define and describe the potential mechanisms underlying the protective effects of breastfeeding, and (3) examine the potential effects of air pollution on breastmilk composition and lactation. A literature search was conducted using electronic databases. Existing evidence suggests that breastfeeding has a protective effect on adverse outcomes of indoor and outdoor air pollution exposure in respiratory (infections, lung function, asthma symptoms) and immune (allergic, nervous and cardiovascular) systems, as well as under-five mortality in both developing and developed countries. However, some studies reported no protective effect of breastfeeding or even negative effects of breastfeeding for under-five mortality. Several possible mechanisms of the breastfeeding protective effect were proposed, including the beneficial influence of breastfeeding on immune, respiratory, and nervous systems, which are related to the immunomodulatory, anti-inflammatory, anti-oxidant, and neuroprotective properties of breastmilk. Breastmilk components responsible for its protective effect against air pollutants exposure may be long chain polyunsaturated fatty acids (LC PUFA), antioxidant vitamins, carotenoids, flavonoids, immunoglobins, and cytokines, some of which have concentrations that are diet-dependent. However, maternal exposure to air pollution is related to increased breastmilk concentrations of pollutants (e.g., Polycyclic aromatic hydrocarbons (PAHs) or heavy metals in particulate matter (PM)). Nonetheless, environmental studies have confirmed that breastmilk's protective effects outweigh its potential health risk to the infant. Mothers should be encouraged and supported to breastfeed their infants due to its unique health benefits, as well as its limited ecological footprint, which is associated with decreased waste production and the emission of pollutants.

Early life risk factors of motor, cognitive and language development: a pooled analysis of studies from low/middle-income countries

OBJECTIVE

To determine the magnitude of relationships of early life factors with child development in low/middle-income countries (LMICs).

DESIGN

Meta-analyses of standardised mean differences (SMDs) estimated from published and unpublished data.

DATA SOURCES

We searched Medline, bibliographies of key articles and reviews, and grey literature to identify studies from LMICs that collected data on early life exposures and child development. The most recent search was done on 4 November 2014. We then invited the first authors of the publications and investigators of unpublished studies to participate in the study.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies that assessed at least one domain of child development in at least 100 children under 7 years of age and collected at least one early life factor of interest were included in the study.

ANALYSES

Linear regression models were used to assess SMDs in child development by parental and child factors within each study. We then produced pooled estimates across studies using random effects meta-analyses.

RESULTS

We retrieved data from 21 studies including 20 882 children across 13 LMICs, to assess the associations of exposure to 14 major risk factors with child development. Children of mothers with secondary schooling had 0.14 SD (95% CI 0.05 to 0.25) higher cognitive scores compared with children whose mothers had primary education. Preterm birth was associated with 0.14 SD (-0.24 to -0.05) and 0.23 SD (-0.42 to -0.03) reductions in cognitive and motor scores, respectively. Maternal short stature, anaemia in infancy and lack of access to clean water and sanitation had significant negative associations with cognitive and motor development with effects ranging from -0.18 to -0.10 SDs.

CONCLUSIONS

Differential parental, environmental and nutritional factors contribute to disparities in child development across LMICs. Targeting these factors from prepregnancy through childhood may improve health and development of children.

Psychological effects of breastfeeding on children and mothers

While the nutritional and physical health benefits of breastfeeding are well established, accumulating research demonstrates the far-reaching psychological effects of breastfeeding on children and their mothers. Here, we provide a non-exhaustive review of the empirical evidence, showing that breastfeeding impacts children's brain, cognitive, and socio-emotional development. In mothers, research is presented indicating that breastfeeding influences mood, affect, stress, and maternal care. The current review aims to provide a broad overview of existing findings on the psychological effects of breastfeeding, highlighting the important role that breastfeeding plays across several dimensions of psychological functioning. We also discuss the potential mechanisms that may underpin the observed effects, provide a constructive commentary on the limitations of the existing work, and put forth some considerations when evaluating this line of research.

Assessment of risk factors for developmental delays among children in a rural community of North India: A cross-sectional study

BACKGROUND

Initial formative years in every children's life are critical for their optimal development, as these frame the foundation of future well-being. With a varied prevalence of developmental delays (DDs) in the world and most of the studies representing the hospital-based data. The present study was aimed to find the prevalence and risk factors for DDs (domain wise) in children aged 2 months to 6 years in the rural area of North India.

METHODS

This was a cross-sectional study in which a multistage random sampling technique was used. From 30 Anganwadi centers, 450 children aged 2 months-6 years were taken in the study. Rashtriya Bal Swasthya Karyakram screening tool developed by the Ministry of Health and Family Welfare, India, was used for developmental screening. Binary logistic regression analysis was done to identify the predictors for DDs (domain wise).

RESULTS

Seventy-three (16.2%) children were found to have DDs and 60 (13.3%) children had the global DDs. About 84/421 (20.0%) children had cognitive delay, followed by 43/450 (9.6%) children who had delay in speech and language area. About 17/190 (8.9%) children had social delay while 26/407 (6.4%) children had hearing and vision impairment. Gross motor delay was seen in 24/450 (5.3%) children and 16/300 (5.3%) children had fine motor delay. Gestational age (adjusted odds ratio [AOR] - 13.30), complications during delivery (AOR - 25.79), meconium aspiration (AOR - 12.81), and child never breastfed (AOR - 8.34) were strong predictors for the delay in different domains of developmental milestones.

CONCLUSION

Socio-economic, ante-natal, natal and post-natal factors should be considered for prompt identification and initiation of intervention for DDs.

RECOMMENDATION

There is a need for increasing awareness and knowledge of parents regarding the achievement of developmental milestones according to the age. A multipronged approach to the holistic treatment of developmentally delayed children for early intervention is required.

The Long-Term Effects of Dietary Nutrient Intakes during the First 2 Years of Life in Healthy Infants from Developed Countries: An Umbrella Review

The role of both qualitative and quantitative early nutrient intakes on later health has been suggested for decades and supported by observational studies on humans, mainly preterm and low-birth-weight infants, and animal models. However, to date, no comprehensive review has been conducted to evaluate the full impact of nutritional variables on healthy full-term infants. This umbrella review considers meta-analyses and systematic reviews on the health effects of different nutritional exposures or interventions in the first 2 y of life of healthy full-term infants in developed countries. The systematic reviews and meta-analyses published by March 2018 in MEDLINE, EMBASE, and Cochrane Database of Systematic Reviews were included. The following outcomes were considered: growth and obesity, cardiovascular disease, neurodevelopment, allergy and autoimmunity, infections, and malignancy. Breastfeeding and complementary feeding were considered separately and analyzed by means of their differences in delivering heterogeneous food-related variables. The resulting data on the long-term effect of early nutritional differences in healthy full-term infants were found to be inconclusive. Only breastfeeding has a beneficial effect, which is nevertheless slight and limited to just a few outcome measures, whereas the type and duration required to be effective are still unclear. As regards the complementary feeding period, no clear effects of different dietary interventions emerge in terms of health outcomes. Available evidence on the health effects of differences in early nutrition in healthy full-term infants still remains largely inconclusive.

Association between Breastmilk LC PUFA, Carotenoids and Psychomotor Development of Exclusively Breastfed Infants

The first months of infant life are crucial for proper neurodevelopment, which may be influenced by several factors, including nutrition and nutrients (e.g., long-chain polyunsaturated fatty acids (LC PUFA) and carotenoids) of which the concentration in breastmilk is diet-dependent. This study analysed the relationship between the average concentrations of selected LC PUFA and carotenoids in breastmilk samples from the first and third months of lactation and the psychomotor development of exclusively breastfed infants at the sixth month of life. Infant psychomotor development was assessed using the Children Development Scale (DSR). The average age of infants during the assessment was 6.6 ± 0.2 months and 30.9 ± 3.8 years for mothers (n = 39 mother⁻infant pairs). The average concentration of docosahexaenoic acid (DHA) was 0.50% of fatty acids. The average concentration of carotenoids was 33.3 nmol/L for β-carotene, 121 nmol/L for lycopene and 33.3 nmol/L for lutein + zeaxanthin. The total results of the Performance scale and Motor subscale were 39 centiles and 4.1 points, respectively. Adjusted multivariate regression models revealed associations between breastmilk DHA and motor development (β = 0.275; p ≤ 0.05), α-linolenic acid (ALA; β = 0.432; p ≤ 0.05), n-3 LC PUFA (β = 0.423; p ≤ 0.05) and β-carotene (β = 0.359; p ≤ 0.05). In addition, an association between the Perception subscale and DHA was observed (β = 0.316; p ≤ 0.05; model 2). There were no significant associations between the overall Performance scale scores. Due to the positive association between concentrations of n-3 LC PUFA (ALA and DHA) and β-carotene in breastmilk and infant motor development, it is important to provide these nutrients with breastmilk. According to the diet-dependent concentration of these compounds in breastmilk, breastfeeding mothers should have a diet abundant in dietary sources of these nutrients, e.g., fish, nuts, seeds, vegetable oils, vegetables and fruits.

Exposure to prenatal secondhand smoke and early neurodevelopment: Mothers and Children's Environmental Health (MOCEH) study

BACKGROUND

The association between exposure to secondhand smoke (SHS) during pregnancy and a child's neurodevelopment has not been established yet. We explored the association between prenatal exposure to SHS and neurodevelopment at 24 months of age considering genetic polymorphism and breastfeeding in 720 mothers and their offspring enrolled in the Korean multicenter birth cohort study (Mothers and Children Environmental Health, MOCEH).

METHODS

We quantified urine cotinine concentrations in mothers once from 12th to 20th gestational weeks and excluded those whose urine cotinine levels exceeded 42.7 ng/ml to represent SHS exposure in early pregnancy. Mental developmental index (MDI) and psychomotor developmental index (PDI) values were measured using the Korean version of the Bayley Scales of Infant Development II (K-BSID-II) at 24 months of age. A general linear model was used to assess the relationship between maternal urinary cotinine level and neurodevelopment.

RESULTS

MDI scores were inversely associated with cotinine [β = - 2.73; 95% confidence interval (CI): - 5.32 to - 0.15] in children whose mothers had early pregnancy urinary cotinine levels >1.90 ng/ml. No association was evident in children whose mothers had cotinine levels ≤1.90 ng/ml. This negative association was more pronounced in children whose mothers had both Glutathione S-transferases mu 1 (GSTM1) and theta 1 (GSTT1) null type [β = - 5.78; 95% CI: -10.69 to - 0.87], but not in children whose mothers had any present type of GSTM1/GSTT1 [β = - 1.64; 95% CI: -4.79 to 1.52]. The association was no longer significant when children received breast milk exclusively for up to 6 months [β = - 0.24; 95% CI: -4.69 to 4.20] compared to others [β = - 3.75; 95% CI: -7.51 to 0.00]. No significant association was found for PDI.

CONCLUSIONS

Maternal exposure to SHS during pregnancy may result in delayed MDI in early childhood. This effect might be modified by genetic polymorphism and breastfeeding behavior.

Breastfeeding and behavioural problems: Propensity score matching with a national cohort of infants in Chile

IMPORTANCE

Potential effects of breast feeding on children's behaviour remains an elusive debate given inherent methodological challenges. Propensity score matching affords benefits by ensuring greater equivalence on observable social and health determinants, helping to reduce bias between groups.

OBJECTIVES

We examined whether the duration of breast feeding had an impact on children's externalising and internalising behaviours.

STUDY DESIGN

A cohort study (Encuesta Longitudinal de la Primera Infancia cohort) that included 3037 Chilean families who were enrolled in 2010. Follow-up data was collected in 2012.

SETTING

General community.

PARTICIPANTS

Population-based sample. Eligibility criteria: children born full-term with complete data on matching variables. Matching variables included: healthcare system as a proxy of income, presence of a partner/spouse in the household, maternal age, educational level, IQ, working status, type of work, diagnosis of prenatal depression by a healthcare professional, smoking during pregnancy, delivery type, child sex, weight at birth, incubation following delivery, and child age.

EXPOSURE

Duration of breast feeding.

MAIN OUTCOMES AND MEASURES

Externalising and internalising problems assessed using the Child Behaviour Checklist.

RESULTS

Matched results revealed benefits of any breast feeding, up to 6 months, on emotional reactivity and somatic complaints (mean difference of -1.00, 95% CI, -1.84 to -0.16 and -1.02, 95% CI, -1.76 to -0.28, respectively). Children breast fed between 7 and 12 months also had reduced scores on emotional reactivity, in addition to attention problems (mean difference of -0.86, 95% CI, -1.66 to -0.06 and -0.50, 95% CI, -0.93 to -0.07, respectively). No benefits were observed for children breast fed 13 months or more.

CONCLUSION

Reduced internalising difficulties and inattention were found in children breast fed up to a year, suggesting that breast feeding may have beneficial impacts on these areas of development. The magnitude of effect was modest. Extended durations of breast feeding did not appear to offer any benefits.

Associations between prenatal and childhood PBDE exposure and early adolescent visual, verbal and working memory

BACKGROUND

Prenatal and childhood exposure to polybrominated diphenyl ether (PBDE) flame retardants has been inversely associated with cognitive performance, however, few studies have measured PBDE concentrations in samples collected during both prenatal and postnatal periods.

METHODS

We examined prenatal (cord) and childhood (ages 2, 3, 5, 7 and 9 years) plasma PBDE concentrations in relation to memory outcomes assessed between the ages of 9 and 14 years. The study sample includes a subset (n = 212) of the African American and Dominican children enrolled in the Columbia Center for Children's Environmental Health Mothers and Newborns birth cohort. We used multivariable linear regression to examine associations between continuous log₁₀-transformed PBDE concentrations and performance on tests of visual, verbal and working memory in age-stratified models. We additionally used latent class growth analysis to estimate trajectories of exposure across early life, which we analyzed as a categorical variable in relation to memory outcomes. We examined interactions between PBDE exposure and sex using cross-product terms.

RESULTS

Associations between prenatal exposure and working memory significantly varied by sex (p-interaction = 0.02), with inverse relations observed only among girls (i.e. β_BDE-47 = -7.55, 95% CI: -13.84, -1.24). Children with sustained high concentrations of BDEs-47, 99 or 100 across childhood scored approximately 5-8 standard score points lower on tests of visual memory. Children with PBDE plasma concentrations that peaked during toddler years performed better on verbal domains, however, these associations were not statistically significant.

CONCLUSIONS

Exposure to PBDEs during both prenatal and postnatal periods may disrupt memory domains in early adolescence. These findings contribute to a substantial body of evidence supporting the developmental neurotoxicity of PBDEs and underscore the need to reduce exposure among pregnant women and children.

Early nutrition influences developmental myelination and cognition in infants and young children

Throughout early neurodevelopment, myelination helps provide the foundation for brain connectivity and supports the emergence of cognitive and behavioral functioning. Early life nutrition is an important and modifiable factor that can shape myelination and, consequently, cognitive outcomes. Differences in the nutritional composition between human breast and formula milk may help explain the functional and cognitive disparity often observed between exclusively breast versus formula-fed children. However, past cognitive and brain imaging studies comparing breast and formula feeding are often: cross-sectional; performed in older children and adolescents relying on parental recall of infant feeding; and generally treat formula-fed children as a single group despite the variability between formula compositions. Here we address some of these weakness by examining longitudinal trajectories of brain and neurocognitive development in children who were exclusively breastfed versus formula-fed for at least 3 months. We further examine development between children who received different formula compositions. Results reveal significantly improved overall myelination in breastfed children accompanied by increased general, verbal, and non-verbal cognitive abilities compared to children who were exclusively formula-fed. These differences were found to persist into childhood even with groups matched for important socioeconomic and demographic factors. We also find significant developmental differences depending on formula composition received and that, in particular, long-chain fatty acids, iron, choline, sphingomyelin and folic acid are significantly associated with early myelination trajectories. These results add to the consensus that prolonged and exclusive breastfeeding plays an important role in early neurodevelopment and childhood cognitive outcomes.

Antenatal corticosteroids: an assessment of anticipated benefits and potential risks

Antenatal corticosteroids are standard of care for pregnancies at risk of preterm delivery between 24-34 weeks' gestational age. Recent trials demonstrate modest benefits from antenatal corticosteroids for late preterm and elective cesarean deliveries, and antenatal corticosteroids for periviable deliveries should be considered with family discussion. However, many women with threatened preterm deliveries receive antenatal corticosteroids but do not deliver until >34 weeks or at term. The net effect is that a substantial fraction of the delivery population will be exposed to antenatal corticosteroids. There are gaps in accurate assessments of benefits of antenatal corticosteroids because the randomized controlled trials were performed prior to about 1990 in pregnancies generally >28 weeks. The care practices for the mother and infant survival were different than today. The randomized controlled trial data also do not strongly support the optimal interval from antenatal corticosteroid treatment to delivery of 1-7 days. Epidemiology-based studies using large cohorts with >85% of at-risk pregnancies treated with antenatal corticosteroids probably overestimate the benefits of antenatal corticosteroids. Although most of the prematurity-associated mortality is in low-resource environments, the efficacy and safety of antenatal corticosteroids in those environments remain to be evaluated. The short-term benefits of antenatal corticosteroids for high-risk pregnancies in high-resource environments certainly justify antenatal corticosteroids as few risks have been identified over many years. However, cardiovascular and metabolic abnormalities have been identified in large animal models and cohorts of children exposed to antenatal corticosteroids that are consistent with fetal programming for adult diseases. These late effects of antenatal corticosteroids suggest caution for the expanded use of antenatal corticosteroids beyond at-risk pregnancies at 24-34 weeks. A way forward is to develop noninvasive fetal assessments to identify pregnancies across a wider gestational age that could benefit from antenatal corticosteroids.

Improved rates of exclusive breastfeeding at 14 weeks of age in KwaZulu Natal, South Africa: what are the challenges now?

Background

Increasing the rate of exclusive breastfeeding (EBF) to 50% in the first six months of life is one of six major global targets set by the United Nations Decade of Nutrition, and is essential to achieve the sustainable development goals to eradicate hunger and end malnutrition by 2030.

Methods

A survey using multistage random sampling design included 99 primary health care (PHC) clinics in all 11 districts in KwaZulu-Natal (KZN). All mothers and caregivers of infants 14 weeks of age attending the clinics in the study period were requested to participate in a structured interview to explore feeding practices since birth. As non-maternal caregivers may not have detailed knowledge of feeding practices, they provided limited information about current feeding practices. Respondents who consistently reported giving no other food or fluids except breastmilk since birth were classified as practising exclusive breastfeeding (EBF), and those who were currently breastfeeding but had given other food or fluids since birth were categorised as practising mixed breastfeeding (MBF).

Results

A total of 4172 interviews were conducted with mothers and caregivers of 14 week old infants. Among mothers 49.8% were EBF, 23.1% were MBF and 27.0% were not breastfeeding. Among non-maternal caregivers 11.8% reported EBF, 23.4% MBF and 62.3% were not giving breastmilk. Higher education (OR 0.6, 95% CI 0.4–0.8) and being in the highest socio-economic tertile (OR 0.7, 95% CI 0.6–0.9) were risk factors for not practising EBF, while returning to work (OR 0.3, 95% CI 0.2–0.3) or school (OR 0.2 95% CI, 0.1–0.3) was associated with less EBF. HIV-positive mothers were more likely to have never started breastfeeding (OR 3.6, 95% CI 2.7–4.8). However, they were similar in having stopped breastfeeding by 14 weeks (OR 1.1, 95% CI 0.9–1.4) compared to HIV-negative mothers, and, they had similar rates of EBF at 14 weeks of age (OR 1.0, 95% CI 0.9–1.3).

Conclusions

Estimates of breastfeeding practices at 14 weeks in KZN are higher than previously shown. However, particular challenges that should be addressed if international targets for EBF are to be achieved include improving breastfeeding practices of HIV positive mothers and supporting all mothers, particularly working or schooling mothers to continue giving breastmilk while they are away from their children.

Association between breastfeeding and better preserved cognitive ability in an elderly cohort of Finnish men

BACKGROUND

Being breastfed in infancy has been shown to benefit neurodevelopment. However, whether the benefits persist to old age remains unclear.

METHODS

We examined the associations between breastfeeding and its duration on cognitive ability in young adulthood and old age, and on aging-related cognitive change over five decades. In total, 931 men from the Helsinki Birth Cohort Study born in 1934-1944 in Finland took the Finnish Defence Forces Basic Intellectual Ability Test (total and verbal, arithmetic and visuospatial subtest scores) twice, at ages 20.2 and 67.9 years, and had data on breastfeeding (yes v. no) and its duration ('never breastfed', 'up to 3', '3 to 6' and '6 or more months'). Linear and mixed model regressions tested the associations.

RESULTS

At 20.2 years, breastfed men had higher cognitive ability total and visuospatial subtest scores [mean differences (MDs) ranged between 3.0-3.9, p values < 0.013], and its longer duration predicted higher cognitive ability total and arithmetic and visuospatial subtest scores (MDs ranged between 3.0 and 4.8, p values < 0.039). At 67.9 years, breastfed men had higher total cognitive ability and all subtest scores (MDs ranged between 2.6 and 3.4, p values < 0.044) and its longer duration predicted all cognitive ability scores (MDs ranged between 3.1 and 4.7, p values < 0.050). Verbal subtest scores decreased over five decades in men who were never breastfed or were breastfed for 3 months or less, and increased in those breastfed for longer than 3 months.

CONCLUSIONS

Neurodevelopmental advantages of breastfeeding and its longer duration persist into old age, and longer duration of breastfeeding may benefit aging-related change, particularly in verbal reasoning ability.

Exclusive breastfeeding promotion and neuropsychological outcomes in 5-8 year old children from Uganda and Burkina Faso: Results from the PROMISE EBF cluster randomized trial

BACKGROUND

The beneficial effects from exclusive breastfeeding (EBF) have been widely acknowledged. We assessed the effect of exclusive breastfeeding promotion by peer counsellors in Uganda and Burkina Faso, on cognitive abilities, social emotional development, school performance and linear growth among 5-8 years old children.

METHODS

Children in the PROMISE EBF trial (2006-2008) were re-enrolled in the follow-up PROMISE Saving Brains (SB) study (2013-2015). Caretaker interviews captured sociodemographic characteristics and social emotional development using the parent version of the Strengths and Difficulties Questionnaire (SDQ). Overall cognition and working memory were assessed using the Kaufman Assessment Battery for Children, second edition (KABC2), cognitive flexibility was measured with the Child Category Test (CCT), and attention with the Test of Variables of Attention (T.O.V.A), while school performance was measured by a standardized test on arithmetic and reading. Country-pooled, age adjusted z-scores from each of the above outcomes were entered into a linear regression model controlling for confounders.

RESULTS

The number of children re-enrolled in the intervention and control arms were: 274/396 (69.2%) and 256/369 (69.4%) in Uganda and 265/392 (67.6%) and 288/402 (71.6%) in Burkina Faso. Assessment of cognitive ability showed small and no significant differences, of which general cognition (z-scores, 95% CI) showed the largest mean difference: -0.17 (-0.40; 0.05). Social emotional symptoms were similar across arms. There were no differences in school performance or linear growth for age detected.

CONCLUSION

Peer promotion for exclusive breastfeeding in Burkina Faso and Uganda was not associated with differences at 5-8 years of age in a range of measures of child development: cognitive abilities, emotion-behaviour-social symptoms or linear growth. This study from sub Saharan Africa did not reconfirm findings elsewhere that have shown an association between exclusive breastfeeding and cognitive performance. This might be due to a number of methodological limitations inherent in the current study. For example since the majority of the children were breastfed, the benefits of the intervention could have been diluted. Other factors such as the mental and HIV status of the mothers (which were not assessed in the current study) could have affected our results. Hence regarding the effect of exclusive breastfeeding on measures of child neurocognitive development in sub Saharan Africa, the jury is still out.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01882335.