Long-term effects of birth weight and breastfeeding duration on inflammation in early adulthood

Three common assumptions about inflammation, aging, and health that are probably wrong

Chronic inflammation contributes to the onset and progression of cardiovascular disease and other degenerative diseases of aging. But does it have to? This article considers the associations among inflammation, aging, and health through the lens of human population biology and suggests that chronic inflammation is not a normal nor inevitable component of aging. It is commonly assumed that conclusions drawn from research in affluent, industrialized countries can be applied globally; that aging processes leading to morbidity and mortality begin in middle age; and that inflammation is pathological. These foundational assumptions have shifted focus away from inflammation as a beneficial response to infection or injury and toward an understanding of inflammation as chronic, dysregulated, and dangerous. Findings from community-based studies around the world-many conducted in areas with relatively high burdens of infectious disease-challenge these assumptions by documenting substantial variation in levels of inflammation and patterns of association with disease. They also indicate that nutritional, microbial, and psychosocial environments in infancy and childhood play important roles in shaping inflammatory phenotypes and their contributions to diseases of aging. A comparative, developmental, and ecological approach has the potential to generate novel insights into the regulation of inflammation and how it relates to human health over the life course.

Rates of breastfeeding initiation and duration in the United States: data insights from the 2016-2019 Pregnancy Risk Assessment Monitoring System

Introduction

While breastfeeding rates in the United States have been increasing, they remain low by international standards with substantial racial, income and education disparities. This study uses recent population-based data to analyze sociodemographic differences in breastfeeding initiation, duration, and exposure to information and education.

Methods

We used the 2016-2019 Pregnancy Risk Assessment Monitoring System (PRAMS) to compare breastfeeding duration among a representative population from 43 states and the District of Columbia. We modeled the likelihood of never initiating breastfeeding by respondent's age, race and ethnicity, language, marital status, household income, educational attainment, parity and insurance status. We also compared sources of information and education for respondents who never breastfed to those who breastfed up to 6 months.

Results

Among 142,643 new mother respondents, representing an estimated population of 7,426,725 birthing individuals, 12.6% never breastfed, 60.4% reported breastfeeding at 3 months and 54.7% at 6 months. While 75.8% of college graduates reported breastfeeding at 3 months, this was only 37.8% of respondents with high school or less. Among those with the lowest six-month rates were non-Hispanic Black participants (36.3%) and those age < 20 (25.5%). Respondents with Medicaid coverage for their delivery were 25% more likely to have never breastfed than the privately insured. Respondents reporting household income <$20,000 were 57% more likely to have never breastfed as compared to those with household income>$85,000. While 64.1% of those breastfeeding at 6 months reported receiving information from "my" doctor', this was only 13.0% of those who never breastfeed.

Discussion

Improved breastfeeding rates could have significant effects on reducing health disparities in the United States. Clinical and public health policy initiatives need to include culturally sensitive breastfeeding education before and after childbirth, with psychological and direct support from obstetrics and primary care providers. Health plans should support home and community-based in-person and telelactation consulting services. Public policies such as paid family and medical leave and workplace accommodations will also be critical. Given the huge implications of breastfeeding rates on the development of infant immune defenses and a healthy microbiome, improving breastfeeding rates should be a much more important public health priority in the United States.

Progression of C-reactive protein from birth through preadolescence varies by mode of delivery

Introduction

Delivery via caesarean section (C-section) has been associated with an increased risk of childhood chronic diseases such as obesity and asthma, which may be due to underlying systemic inflammation. However, the impact of specific C-section types may be differential, as emergency C-sections typically involve partial labor and/or membrane rupture. Our objectives were to determine if mode of delivery associates with longitudinal profiles of high sensitivity CRP (hs-CRP) -a marker of systemic inflammation-from birth through preadolescence, and to examine if CRP mediates the association between mode of delivery and preadolescent body mass index (BMI).

Methods

Data from the WHEALS birth cohort (N = 1,258) were analyzed; 564 of the 1,258 children in the cohort had data available for analysis. Longitudinal plasma samples (birth through 10-years of age) from 564 children from were assayed for hs-CRP levels. Maternal medical records were abstracted to obtain mode of delivery. Growth mixture models (GMMs) were used to determine classes of hs-CRP trajectories. Poisson regression with robust error variance was used to calculate risk ratios (RRs).

Results

Two hs-CRP trajectory classes were identified: class 1 (76% of children) was characterized by low hs-CRP, while class 2 (24% of children) was characterized by high and steadily increasing hs-CRP. In multivariable models, children delivered via planned C-section had 1.15 times higher risk of being in hs-CRP class 2, compared to vaginal deliveries (p = 0.028), while no association was found for unplanned C-section deliveries [RR (95% CI) = 0.96 (0.84, 1.09); p = 0.49]. Further, the effect of planned C-section on BMI z-score at age 10 was significantly mediated by hs-CRP class (percent mediated = 43.4%).

Conclusions

These findings suggest potentially beneficial effects of experiencing partial or full labor, leading to a lower trajectory of systemic inflammation throughout childhood and decreased BMI during preadolescence. These findings may have implications for chronic disease development later in life.

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.

Breastfeeding in infancy and mortality in middle and late adulthood: A prospective cohort study and meta-analysis

BACKGROUND

Breastfeeding in infancy is associated with a lower risk of mortality among children, but the impact on mortality in middle and late adulthood remains unknown.

OBJECTIVES

To assess the association between breastfeeding in infancy and mortality in middle and late adulthood.

METHODS

We included 383,627 participants aged 40-73 from the UK Biobank (2006-2010) and followed up until 2021. Hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause and cause-specific mortality according to breastfeeding in infancy were estimated with Cox proportional hazards regression models. We further did a meta-analysis, including results from our present study and three other cohort studies (PROSPERO; number CRD42022348925).

RESULTS

During a total of 4732,751 person-years of follow-up, 25,581 deaths were identified. Breastfeeding in infancy was associated with lower risks of mortality in middle and late adulthood, with adjusted HRs (95% CIs) of 0.95 (0.93-0.98) for all-cause mortality; 0.91 (0.87-0.96) for cardiovascular mortality and 0.94 (0.874-0.999) for respiratory mortality. Specifically, the association with mortality seemed to attenuate with age - stronger in middle-aged adults than in older adults. A similar association between breastfeeding in infancy and all-cause mortality was found in the meta-analysis.

CONCLUSION

Breastfeeding in infancy is associated with a lower risk of mortality - even decades later - in middle and late adulthood.

The Deferred Action for Childhood Arrivals program and birth outcomes in California: a quasi-experimental study

BACKGROUND

The Deferred Action for Childhood Arrivals (DACA) program provides temporary relief from deportation and work permits for previously undocumented immigrants who arrived as children. DACA faced direct threats under the Trump administration. There is select evidence of the short-term impacts of DACA on population health, including on birth outcomes, but limited understanding of the long-term impacts.

METHODS

We evaluated the association between DACA program and birth outcomes using California birth certificate data (2009-2018) and a difference-in-differences approach to compare post-DACA birth outcomes for likely DACA-eligible mothers to birth outcomes for demographically similar DACA-ineligible mothers. We also separately compared birth outcomes by DACA eligibility status in the first 3 years after DACA passage (2012-2015) and in the subsequent 3 years (2015-2018) - a period characterized by direct threats to the DACA program - as compared to outcomes in the years prior to DACA passage.

RESULTS

In the 7 years after its passage, DACA was associated with a lower risk of small-for-gestational age (- 0.018, 95% CI: - 0.035, - 0.002) and greater birthweight (45.8 g, 95% CI: 11.9, 79.7) for births to Mexican-origin individuals that were billed to Medicaid. Estimates were consistent but of smaller magnitude for other subgroups. Associations between DACA and birth outcomes were attenuated to the null in the period that began with the announcement of the Trump U.S. Presidential campaign (2015-2018), although confidence intervals overlapped with estimates from the immediate post-DACA period.

CONCLUSIONS

These findings suggest weak to modest initial benefits of DACA for select birthweight outcomes during the period immediately following DACA passage for Mexican-born individuals whose births were billed to Medicaid; any benefits were subsequently attenuated to the null. The benefits of DACA for population health may not have been sufficient to counteract the impacts of threats to the program's future and heightened immigration enforcement occurring in parallel over time.

The Role of Human Milk Lipids and Lipid Metabolites in Protecting the Infant against Non-Communicable Disease

Non-communicable diseases continue to increase globally and have their origins early in life. Early life obesity tracks from childhood to adulthood, is associated with obesity, inflammation, and metabolic dysfunction, and predicts non-communicable disease risk in later life. There is mounting evidence that these factors are more prevalent in infants who are formula-fed compared to those who are breastfed. Human milk provides the infant with a complex formulation of lipids, many of which are not present in infant formula, or are present in markedly different concentrations, and the plasma lipidome of breastfed infants differs significantly from that of formula-fed infants. With this knowledge, and the knowledge that lipids have critical implications in human health, the lipid composition of human milk is a promising approach to understanding how breastfeeding protects against obesity, inflammation, and subsequent cardiovascular disease risk. Here we review bioactive human milk lipids and lipid metabolites that may play a protective role against obesity and inflammation in later life. We identify key knowledge gaps and highlight priorities for future research.

Nutrition during Pregnancy and Lactation: Epigenetic Effects on Infants’ Immune System in Food Allergy

Food allergies are an increasing health problem worldwide. They are multifactorial diseases, in which the genome alone does not explain the development of the disease, but a genetic predisposition and various environmental factors contribute to their onset. Environmental factors, in particular nutritional factors, in the early stages of life are recognized as key elements in the etiology of food allergies. There is growing evidence advising that nutrition can affect the risk of developing food allergies through epigenetic mechanisms elicited by the nutritional factors themselves or by modulating the gut microbiota and its functional products. Gut microbiota and postbiotics can in turn influence the risk of food allergy development through epigenetic mechanisms. Epigenetic programming accounts not only for the short-term effects on the individual’s health status, but also for those observed in adulthood. The first thousand days of life represent an important window of susceptibility in which environmental factors, including nutritional ones, can influence the risk of developing allergies through epigenetic mechanisms. From this point of view, it represents an interesting window of opportunity and intervention. This review reports the main nutritional factors that in the early stages of life can influence immune oral tolerance through the modulation of epigenetic mechanisms.

Perinatal and Early-Life Nutrition, Epigenetics, and Allergy

Epidemiological studies have shown a dramatic increase in the incidence and the prevalence of allergic diseases over the last several decades. Environmental triggers including risk factors (e.g., pollution), the loss of rural living conditions (e.g., farming conditions), and nutritional status (e.g., maternal, breastfeeding) are considered major contributors to this increase. The influences of these environmental factors are thought to be mediated by epigenetic mechanisms which are heritable, reversible, and biologically relevant biochemical modifications of the chromatin carrying the genetic information without changing the nucleotide sequence of the genome. An important feature characterizing epigenetically-mediated processes is the existence of a time frame where the induced effects are the strongest and therefore most crucial. This period between conception, pregnancy, and the first years of life (e.g., first 1000 days) is considered the optimal time for environmental factors, such as nutrition, to exert their beneficial epigenetic effects. In the current review, we discussed the impact of the exposure to bacteria, viruses, parasites, fungal components, microbiome metabolites, and specific nutritional components (e.g., polyunsaturated fatty acids (PUFA), vitamins, plant- and animal-derived microRNAs, breast milk) on the epigenetic patterns related to allergic manifestations. We gave insight into the epigenetic signature of bioactive milk components and the effects of specific nutrition on neonatal T cell development. Several lines of evidence suggest that atypical metabolic reprogramming induced by extrinsic factors such as allergens, viruses, pollutants, diet, or microbiome might drive cellular metabolic dysfunctions and defective immune responses in allergic disease. Therefore, we described the current knowledge on the relationship between immunometabolism and allergy mediated by epigenetic mechanisms. The knowledge as presented will give insight into epigenetic changes and the potential of maternal and post-natal nutrition on the development of allergic disease.

A highly sensitive multiplex immunoassay for inflammatory cytokines in dried blood spots

OBJECTIVES

Inflammatory cytokines are key regulators of inflammation, but current measurement approaches require venous blood to quantify low circulating concentrations associated with chronic, low-grade inflammation. This article describes a highly sensitive multiplex immunoassay protocol for the measurement of IL6, IL8, IL10, and TNFα in finger stick dried blood spot (DBS) samples.

METHODS

The protocol uses a multiplex electrochemiluminescent immunoassay platform. The following measures of assay performance were evaluated: reliability (inter-assay percent coefficient of variation; %CV), precision (intra-assay %CV), lower limit of detection (LLD), linearity of dilution, and agreement with results from matched plasma samples.

RESULTS

Analysis of three control samples across the assay range indicated an acceptable level of precision and reliability for each cytokine. Linearity of dilution returned average values that ranged from 104.1 to 127.6% of expected. Lower limits of detection for IL6, IL8, and IL10 were <0.5, and <1.0 pg/ml for TNFα. Level of agreement in results between matched DBS and plasma samples was high for all cytokines except for IL8.

CONCLUSIONS

Finger stick DBS sampling provides a viable alternative to venipuncture for the quantification of IL6, IL10, and TNFα at low concentrations associated with chronic inflammation. The presence of red blood cells may interfere with the quantification of IL8 in DBS. In facilitating blood collection in nonclinical settings this method can advance scientific understandings of how social and ecological contexts shape immune function and health over the life course.

An Overview of Gut Microbiota and Colon Diseases with a Focus on Adenomatous Colon Polyps

It is known and accepted that the gut microbiota composition of an organism has an impact on its health. Many studies deal with this topic, the majority discussing gastrointestinal health. Adenomatous colon polyps have a high prevalence as colon cancer precursors, but in many cases, they are hard to diagnose in their early stages. Gut microbiota composition correlated with the presence of adenomatous colon polyps may be a noninvasive and efficient tool for diagnosis with a high impact on human wellbeing and favorable health care costs. This review is meant to analyze the gut microbiota correlated with the presence of adenomatous colon polyps as the first step for early diagnosis, prophylaxis, and treatment.

Revisiting the relationship between perceived discrimination and health: Evidence from sibling models with multiple health measures

Perceived discrimination (PD) is known to be significantly related to health outcomes. This link, however, warrants further scrutiny due to the possibility of unobserved family-level confounding. Using the Add Health and sibling fixed-effect approach, we examine whether the relationship between PD and health is confounded by family background characteristics such as genetics, family environment, and childhood social context (school and neighborhood effects). While the naive OLS models exhibit significant associations between PD and both physical and psychological health outcomes, our preferred sibling fixed-effect estimates reveal that the observed associations between PD and physical health outcomes are confounded by shared family background. In contrast, the observed associations for psychological health, self-reported health, and some of health behavior outcomes are robust to adjustment for sibling fixed-effects. Furthermore, we find similar overall patterns in the link between PD and health across races/ethnicities.

Nutri-Epigenetics and Gut Microbiota: How Birth Care, Bonding and Breastfeeding Can Influence and Be Influenced?

Maternal lifestyle is an important factor in the programming of an infant's epigenome, in particular when considered alongside the mode of birth and choice of feeding method (i.e., breastfeeding or formula feeding). Beginning in utero, and during the first two years of an infant's life, cells acquire an epigenetic memory of the neonatal exposome which can be influential across the entire lifespan. Parental lifestyle (e.g., malnutrition, alcohol intake, smoke, stress, exposure to xenobiotics and/or drugs) can modify both the maternal and paternal epigenome, leading to epigenetic inheritance in their offspring. This review aims to outline the origin of early life modulation of the epigenome, and to share this fundamental concept with all the health care professionals involved in the development and provision of care during childbirth in order to inform future parents and clinicians of the importance of the this process and the key role it plays in the programming of a child's health.

Detecting the Effects of Early-Life Exposures: Why Fecundity Matters

Prenatal exposures have meaningful effects on health across the lifecourse. Innovations in causal inference have shed new light on these effects. Here, we motivate the importance of innovation in the characterization of fecundity, and prenatal selection in particular. We argue that such innovation is crucial for expanding knowledge of the fetal origins of later life health. Pregnancy loss is common, responsive to environmental factors, and closely related to maternal and fetal health outcomes. As a result, selection into live birth is driven by many of the same exposures that shape the health trajectories of survivors. Lifecourse effects that are inferred without accounting for these dynamics may be significantly distorted by survival bias. We use a set of Monte Carlo simulations with realistic parameters to examine the implications of prenatal survival bias. We find that even in conservatively specified scenarios, true fetal origin effects can be underestimated by 50% or more. In contrast, effects of exposures that reduce the probability of prenatal survival but improve the health of survivors will be overestimated. The absolute magnitude of survival bias can even exceed small effect sizes, resulting in inferences that beneficial exposures are harmful or vice-versa. We also find reason for concern that moderately sized true effects, underestimated due to failure to account for selective survival, are missing from scientific knowledge because they do not clear statistical significance filters. This bias has potential real-world costs; policy decisions about interventions to improve maternal and infant health will be affected by underestimated program impact.

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.

Profiles of gene expression in maternal blood predict offspring birth weight in normal pregnancy

The association between lower birth weight and increased disease risk in adulthood has drawn attention to the physiological processes that shape the gestational environment. We implement genome-wide transcriptional profiling of maternal blood samples to identify subsets of genes and associated transcription control pathways that predict offspring birth weight. Female participants (N = 178, mean = 27.0 years) in a prospective observational birth cohort study were contacted between 2009 and 2014 to identify new pregnancies. An in-home interview was scheduled for early in the third trimester (mean = 30.3 weeks) to collect pregnancy-related information and a blood sample, and birth weight was measured shortly after delivery. Transcriptional activity in white blood cells was determined with a whole-genome gene expression direct hybridization assay. Fifty transcripts were differentially expressed in association with offspring birth weight, with 18 up-regulated in relation to lower birth weight, and 32 down-regulated. Examination of transcription control pathways identified increased activity of NF-κB, AP-1, EGR1, EGR4, and Gfi families, and reduced the activity of CEBP, in association with lower birth weight. Transcript origin analyses identified non-classical CD16+ monocytes, CD1c+ myeloid dendritic cells, and neutrophils as the primary cellular mediators of differential gene expression. These results point toward a systematic regulatory shift in maternal white blood cell activity in association with lower offspring birth weight, and they suggest that analyses of gene expression during gestation may provide insight into regulatory and cellular mechanisms that influence birth outcomes.

Maternal infections during pregnancy and offspring midlife inflammation

Background

Microbial exposures early in life have been found to be associated with lower levels of inflammation in adulthood; however, the role of prenatal exposure to infection on offspring inflammatory profiles is unexplored. The aim was to study if maternal infections during pregnancy are associated with inflammation among offspring in later life and to determine if there are sensitive periods of exposure.

Methods

The study was comprised of 1719 participants in the Copenhagen Aging and Midlife Biobank (CAMB) who were also members of the Copenhagen Perinatal Cohort (CPC). When the CPC was established, information on maternal infections during pregnancy was prospectively collected by a trained medical doctor. The inflammatory measures collected in late midlife included, C-reactive protein (CRP), Interleukin-6 (IL-6), TNF-alpha (TNF-α) and Interleukin-10 (IL-10). Multivariable ordinary least squared regression models were implemented to explore associations between maternal infection and inflammatory measures in offspring, controlling for maternal smoking, pre-pregnancy body mass index, age, marital status and parity.

Results

Maternal infection was associated with a 7% lower CRP level (95% CI, − 17,5%) among offspring compared with offspring born to women without an infection and similarly an 8% lower level of IL-6 (95% CI -15,1%), and a 9% lower level of IL-10 (95% CI, − 23,20%). However, differences did not reach significance. The effects of infection during the first trimester did not differ from infections later in the pregnancy.

Conclusions

Our results suggested that prenatal exposure to infection may be associated with lower levels of inflammatory markers among adult offspring. Additional prospective studies are needed to further explore this finding.

Pathways linking caesarean delivery to early health in a dual burden context: Immune development and the gut microbiome in infants and children from Galápagos, Ecuador

OBJECTIVES

Global increases in caesarean deliveries are exposing more infants to perinatal environments that are evolutionarily novel and potentially increasing their risks for inflammatory conditions. Yet, the pathways linking caesareans to later health outcomes are not well understood, particularly in dual burden contexts. We test two of the hypothesized pathways, altered immune function and gut microbiota, which may link delivery mode to later health outcomes and test whether these associations persist when controlling for postnatal nutritional and pathogenic exposures.

METHODS

Data come from infants, aged 0 to 2 (n = 41), and young children, aged 2 to 11 (n = 135), from the Galápagos, Ecuador. Differences in morbidity, C-reactive protein (CRP), and gut microbiota by delivery type were tested using linear and logistic regression models adjusted for nutritional and pathogenic exposures and infant age.

RESULTS

Over half of infants and over 40% of children were delivered by caesarean. Morbidity and CRP did not differ between infants or children born by caesarean or vaginally. Microbial taxa abundance differed by delivery mode. Infants born by caesarean had a higher abundance of Firmicutes and a lower relative abundance of Bacteroidales. Children born by caesarean had a higher abundance of Proteobacteria and Enterobacteriales. These differences remained after adjustment for environmental exposure.

CONCLUSIONS

Caesarean delivery is associated with differences in gut microbiota across childhood even in this dual burden context. Our results highlight the importance of examining caesarean delivery across diverse contexts to better understand the impact of perinatal interventions on short- and longer-term health outcomes.

Inflammation-related epigenetic risk and child and adolescent mental health: A prospective study from pregnancy to middle adolescence

In 785 mother-child (50% male) pairs from a longitudinal epidemiological birth cohort, we investigated associations between inflammation-related epigenetic polygenic risk scores (i-ePGS), environmental exposures, cognitive function, and child and adolescent internalizing and externalizing problems. We examined prenatal and postnatal effects. For externalizing problems, one prenatal effect was found: i-ePGS at birth associated with higher externalizing problems (ages 7-15) indirectly through lower cognitive function (age 7). For internalizing problems, we identified two effects. For a prenatal effect, i-ePGS at birth associated with higher internalizing symptoms via continuity in i-ePGS at age 7. For a postnatal effect, higher postnatal adversity exposure (birth through age 7) associated with higher internalizing problems (ages 7-15) via higher i-ePGS (age 7). Hence, externalizing problems were related mainly to prenatal effects involving lower cognitive function, whereas internalizing problems appeared related to both prenatal and postnatal effects. The present study supports a link between i-ePGS and child and adolescent mental health.

Childhood Family Instability and Young Adult Health

American children live in a variety of family structures throughout their childhoods. Such instability in family arrangements is common and has important demonstrated implications for short-term child outcomes. However, it is not known whether family instability experienced in childhood has enduring health consequences across the life course. Using demographic, social, and biological data from the National Longitudinal Study of Adolescent to Adult Health, we investigate the family stress model, testing the relationship between parental family instability in childhood and four biological markers of health in young adulthood. This is the first study to examine whether the accumulation of family change in childhood leaves a lasting physiological residue. While family instability is associated with poorer short-term behavioral and socioeconomic outcomes as documented in previous research, we find no evidence of deleterious young adult health consequences. These findings are robust across different measures of physiological health risk and types of family transitions.

Gender Differences in Biological Function in Young Adulthood: An Intragenerational Perspective

Sex/gender differences in health are a function of social and biological factors, and their interplay over the life course. Despite a large body of research documenting sex/gender as a determinant of health behavior and outcomes, far less scholarship examines how these differences are reflected in physiologic function-an important mediator through which social experiences "get under the skin"-in young adulthood. Using nationally representative, longitudinal data from the National Longitudinal Study of Adolescent to Adult Health (Add Health), we examine the relationship between gender and biological function (inflammation and immunosuppression) in young adulthood. Second, we examine the contribution of social and economic circumstances in childhood and early adulthood to gender differences in health. The findings reveal strong gender differences in physiologic function, which are robust to the inclusion of many indicators of the social environment, in both inflammation and immune function.

Adverse childhood experiences and adult inflammation: Findings from the 1958 British birth cohort

BACKGROUND

The relationship between adverse childhood experiences (ACE) and poorer health across the life course is well established. Increased chronic inflammation might be one mechanism through which these associations operate. The aim of this study was to explore the relationship between ACE and adult inflammation using a prospective longitudinal study. We also investigated whether associations were explained by life course socioeconomic, psychological and health behavioural factors, and whether associations differed by gender.

METHODS

Multiply imputed data on 7464 participants of the National Child Development Study (1958 British birth cohort) were used. Prospectively collected data on ACE included care placement, physical neglect, parental separation, family history of offences, mental illness, domestic conflict and alcohol misuse across childhood (0-16 years). Adult inflammation was indicated by C-reactive protein (CRP), fibrinogen and Von Willebrand factor (vWF) at age 44/45. Multivariable linear regression models were used to estimate associations between ACE and adult inflammation.

RESULTS

Graded associations for ACE with CRP and fibrinogen were observed (e.g. CRP: 1 ACE: 4.61% higher, 95% CI: -3.13, 12.97; 2+ ACE: 16.35% higher, 95% CI: 6.87, 26.66). Socioeconomic and health behavioral factors were found to particularly explain these associations. After inclusion of all covariates associations between ACE and mid-life inflammation were no longer significant. Associations did not differ for men and women.

CONCLUSIONS

ACE were associated in a graded manner with adult inflammation in a British birth cohort. The association was explained by life course socioeconomic and health behavioral factors, in particular. This study highlights the importance of protecting children from ACE and its negative health effects, and in supporting children through education and into skilled, secure work.

Birth weight and postnatal microbial exposures predict the distribution of peripheral blood leukocyte subsets in young adults in the Philippines

The immune system not only provides protection against infectious disease but also contributes to the etiology of neoplastic, atopic, and cardiovascular and metabolic diseases. Prenatal and postnatal nutritional and microbial environments have lasting effects on multiple aspects of immunity, indicating that immune processes may play important roles in the developmental origins of disease. The objective of this study is to evaluate the association between birth weight and the distribution of leukocyte (white blood cell) subsets in peripheral blood in young adulthood. Postnatal microbial exposures were also considered as predictors of leukocyte distribution. Participants (n=486; mean age=20.9 years) were drawn from a prospective birth cohort study in the Philippines, and analyses focused on the following cell types: CD4 T lymphocytes, CD8 T lymphocytes, B lymphocytes, natural killer cells, monocytes, granulocytes. Higher birth weight was a strong predictor of higher proportion of CD4 T lymphocytes (B=0.12, s.e.=0.041, P=0.003), lower proportion of CD8 T lymphocytes (B=-0.874, s.e.=0.364, P=0.016), higher CD4:CD8 ratio (B=1.964, s.e.=0.658, P=0.003), and higher B lymphocytes (B=0.062, s.e.=0.031, P=0.047). Measures of microbial exposure in infancy were negatively associated with proportions of B lymphocytes and granulocytes, and lower CD4:CD8 ratio. Leukocytes are the key regulators and effectors of innate and specific immunity, but the origins of variation in the distribution of cell type across individuals are not known. Our findings point toward nutritional and microbial exposures in infancy as potentially important determinants of immune-phenotypes in adulthood, and they suggest that leukocyte distribution is a plausible mechanism through which developmental environments have lasting effects on disease risk in adulthood.

Social and physical environments early in development predict DNA methylation of inflammatory genes in young adulthood

Chronic inflammation contributes to a wide range of human diseases, and environments in infancy and childhood are important determinants of inflammatory phenotypes. The underlying biological mechanisms connecting early environments with the regulation of inflammation in adulthood are not known, but epigenetic processes are plausible candidates. We tested the hypothesis that patterns of DNA methylation (DNAm) in inflammatory genes in young adulthood would be predicted by early life nutritional, microbial, and psychosocial exposures previously associated with levels of inflammation. Data come from a population-based longitudinal birth cohort study in metropolitan Cebu, the Philippines, and DNAm was characterized in whole blood samples from 494 participants (age 20-22 y). Analyses focused on probes in 114 target genes involved in the regulation of inflammation, and we identified 10 sites across nine genes where the level of DNAm was significantly predicted by the following variables: household socioeconomic status in childhood, extended absence of a parent in childhood, exposure to animal feces in infancy, birth in the dry season, or duration of exclusive breastfeeding. To evaluate the biological significance of these sites, we tested for associations with a panel of inflammatory biomarkers measured in plasma obtained at the same age as DNAm assessment. Three sites predicted elevated inflammation, and one site predicted lower inflammation, consistent with the interpretation that levels of DNAm at these sites are functionally relevant. This pattern of results points toward DNAm as a potentially important biological mechanism through which developmental environments shape inflammatory phenotypes across the life course.

Breastfeeding in Infancy Is Associated with Body Mass Index in Adolescence: A Retrospective Cohort Study Comparing American Indians/Alaska Natives and Non-Hispanic Whites

BACKGROUND

American Indians and Alaska Natives have the highest obesity prevalence in the United States, but the influence of early childhood variables on body mass index (BMI; calculated as kg/m2) is not well understood. Previous studies have investigated the association between breastfeeding in infancy and offspring BMI, but rarely included American Indians and Alaska Natives.

OBJECTIVE

This study investigated the association between breastfeeding in infancy and BMI in American Indians and Alaska Native and non-Hispanic white adolescents and young adults.

DESIGN

Longitudinal analysis based on data from the National Longitudinal Study of Adolescent to Adult Health (1994 to 2008).

PARTICIPANTS

Adolescent respondents who self-identified as American Indians and Alaska Native or non-Hispanic white, and whose parents completed the parental questionnaire, reported their height and weight. The final sample included 655 American Indians and Alaska Native and 10,305 non-Hispanic white respondents.

STATISTICAL ANALYSES PERFORMED

Generalized estimating equations were used to measure the mean differences, 95% CIs, and P values of the association between breastfeeding in infancy and offspring BMI in adolescence, stratifying by race, and adjusting for demographic and socioeconomic variables.

RESULTS

The length of breastfeeding was inversely associated with BMI in both populations. American Indians and Alaska Natives that were breastfed for 6 to 12 months or for more than 12 months had a mean BMI of 2.69 (95% CI -3.46 to -1.92; P<0.01) and 1.54 (95% CI -2.75 to -0.33; P<0.05) units lower than those that were never breastfed. Non-Hispanic whites that were breastfed for 3 to 6 months, 6 to 12 months, or more than 12 months had a mean BMI of 0.71 (95% CI -0.93 to -0.50; P<0.01), 0.68 (95% CI -0.87 to -0.50; P<0.01), and 0.85 (95% CI -1.09 to -0.62; P<0.01) units lower than those that were never breastfed. The association between the length of breastfeeding and offspring BMI varied by race (P<0.01).

CONCLUSIONS

Breastfeeding in infancy is associated with lower mean BMI. Future research should investigate causal pathways and whether interventions promoting breastfeeding in American Indians and Alaska Natives can prevent increasing BMI.

Mora‐Faife E, García‐García G, del Valle‐Infante I, Gómez‐Marrero L, Britton J, Fogarty AW. The association of low birth weight with serum C reactive protein in 3-year-old children living in Cuba: A population-based prospective study

OBJECTIVE

Low birthweight is associated with a decreased risk of childhood leukemia and an increased risk of both cardiovascular disease and all-cause mortality in adult life. Possible biological mediators include systemic innate immunity and inflammation. We tested the hypothesis that birthweight was inversely associated with serum high sensitivity C reactive protein assay (hsCRP), a measure of both innate immunity and systemic inflammation.

METHODS

Data on birthweight and current anthropometric measures along with a range of exposures were collected at 1 and 3 years of age in a population-based cohort study of young children living in Havana, Cuba. A total of 986 children aged 3-years-old provided blood samples that were analyzed for serum hsCRP levels.

RESULTS

Nearly 49% of children had detectable hsCRP levels in their serum. Lower birthweight was linearly associated with the natural log of hsCRP levels (beta coefficient -0.70 mg L-1 per kg increase in birthweight, 95% CI: -1.34 to -0.06). This was attenuated but still present after adjustment for the child's sex and municipality (-0.65 mg L-1 per kg birthweight; 95% CI: -1.38 to +0.08). There were no associations between growth from birth or anthropometric measures at 3 years and systemic inflammation.

CONCLUSIONS

Birthweight was inversely associated with serum hsCRP levels in children aged 3 years living in Cuba. These observations provide a potential mechanism that is present at the age of 3 years to explain the association between low birthweight and both decreased childhood leukemia and increased cardiovascular disease in adults.

Breastfeeding, overweight status, and inflammation

Research documents a host of health benefits of breastfeeding for infants and children, including long-term health conditions arising from inflammation. Here, we provide new evidence about this association, focusing on the link between breastfeeding in infancy and inflammation in early adulthood. Our study is based on the National Longitudinal Study of Adolescent to Adult Health (Add Health) which allows us investigate a potentially important mediating pathway - overweight status from early adolescence into young adulthood. Results from pathway analyses in a structural equation modeling framework indicate that, in addition to a direct pathway linking breastfeeding and inflammation, an indirect pathway through overweight status across adolescence into young adulthood partially explains the association between breastfeeding and inflammation. Overweight status, moreover, links breastfeeding to inflammation not only through proximal timing of overweight status, but also through an indirect cascading process of overweight status over the life course that is evident in adolescence. Overall, this study highlights the importance of considering breastfeeding, overweight status and inflammation as dynamic life course processes that contribute to development of health inequalities.

School and family-based interventions for promoting a healthy lifestyle among children and adolescents in Italy: a systematic review

AIMS

Cardiovascular diseases affect adult population but risk factors develop as a result of known or assumed behavior since childhood. In Italy, up to 22.2% of children are overweight, 10.6% are obese, and 2.5% have severe obesity.

METHODS

We performed a systematic review of the literature to identify studies and initiatives addressing health promotion among children in Italy. Given the high heterogeneity of interventions and outcomes assessed we opted to perform a qualitative synthesis of the results. We described also nonrandomized trial where the intervention of primary prevention was very innovative, explained in detail, and reached an improving outcome for participants.

RESULTS

We identified 11 projects since 1983, only five were randomized control trials. Three involved children and teachers of primary and secondary schools and were based on specific curricular lectures about health. One was based on a game developed for high schools with the purpose to promote healthy lifestyle and physical activity. The fifth project was based on an enhanced physical activity program.

CONCLUSION

Our results show that school and family should be considered as the privileged places for health promotion. In Italy, the development of scientific-validated lifestyle interventions for children is still an unmet need.

Insufficient physical activity increases cardiovascular risk in women with low birth mass

Study aim: The aim of the study was to evaluate the relationship between low birth mass and concentration of high-sensitivity C-reactive protein (hsCRP) as a cardiovascular risk factor in young women with various levels of physical activity.

Materials and methods: 102 female students aged 19.7 ± 0.8 (18.6-23.0) were included. The study group was divided according to the declared physical activity: high physical activity (HPA, n = 69) and low physical activity (LPA, n = 33). Anthropometric indices were measured: body mass, height, hip and waist circumference. hsCRP levels were obtained from venous blood samples. Birth body mass (BBM) and birth height were collected from medical documentation.

Results: Women with low BBM and LPA had a significantly higher concentration of hsCRP than women with low BBM and HPA, as well as women with normal BBM.

Conclusions: Low birth mass together with low physical activity is a strong predictor of raised concentration of hsCRP, which correlates with an increased risk of cardiovascular and metabolic diseases. Regular physical activity in women with low birth mass may prevent an increased hsCRP concentration, and as a result decrease the risk of cardiovascular and metabolic diseases.

Breastfeeding and Adult Personality

Five Factor Model (FFM) personality traits are implicated in long-term health-risk behaviors and outcomes. Less research has addressed how early-life experiences are associated with individual differences in these traits in adulthood. We examine whether having been breastfed is associated with adult personality and well-being in the National Longitudinal Study of Adolescent to Adult Health. At Wave 1, caregivers reported whether the target child had been breastfed. At Wave 4, participants (N=13,113; 53% female; M_age=28.98) completed measures of psychological functioning. We tested for mean-level differences in the traits by breastfeeding status (yes/no) and by the duration of breastfeeding, controlling for basic demographic factors and early-life factors that could confound the breastfeeding-personality association (e.g., mother education). Participants who had been breastfed scored lower in neuroticism, anxiety, and hostility and higher in openness and optimism than those not breastfed. A curvilinear relation suggested that neuroticism was lowest for those breastfed for 9-12 months and highest for those either breastfed for >24 months or exclusively bottle-fed. Breastfeeding was unrelated to conscientiousness or state psychological functioning. This research suggests long-term psychological benefits to breastfeeding and indicates that early life experiences are associated with traits that are consequential for adult health.

Early developmental exposures shape trade-offs between acquired and innate immunity in humans

BACKGROUND AND OBJECTIVES

Life history theory predicts resource allocation trade-offs between competing functions and processes. We test the hypothesis that relative investment towards innate versus acquired immunity in humans is subject to such trade-offs and that three types of early developmental exposures are particularly salient in shaping adult immunophenotype: (i) pathogen exposure, (ii) nutritional resources; and (iii) extrinsic mortality cues.

METHODOLOGY

We quantified one aspect each of innate and acquired immune function, via C-reactive protein and Epstein-Barr virus antibodies, respectively, in a sample of 1248 men and women from the Philippines (ca. 21.5 years old). Early developmental exposures were assessed via long-term data collected prospectively since participants' birth (1983-4). We calculated a standardized ratio to assess relative bias towards acquired versus innate immune function and examined its relationship to a suite of predictors via multiple regression.

RESULTS

In partial support of our predictions, some of the measures of higher pathogen exposure, greater availability of nutritional resources, and lower extrinsic mortality cues in early life were associated with a bias toward acquired immunity in both men and women. The immune profile of women, in particular, appeared to be more sensitive to early life pathogen exposures than those of men. Finally, contrary to prediction, women exhibited a greater relative investment toward innate, not acquired, immunity.

CONCLUSIONS AND IMPLICATIONS

Early environments can exert considerable influence on the development of immunity. They affect trade-offs between innate and acquired immunity, which show adaptive plasticity and may differ in their influence in men and women.

Nonlinear Relationship between Birth Weight and Visceral Fat in Adolescents

OBJECTIVE

To determine the association of birth weight with abdominal fat distribution and markers known to increase risk for cardiovascular disease and type 2 diabetes in adolescents.

STUDY DESIGN

In 575 adolescents aged 14-18 years (52% female, 46% black), birth weight was obtained by parental recall. Fasting blood samples were measured for glucose, insulin, lipids, adiponectin, leptin, and C-reactive protein. Subcutaneous abdominal adipose tissue and visceral adipose tissue were assessed by magnetic resonance imaging.

RESULTS

When we compared markers of cardiometabolic risk across tertiles of birth weight, adjusting for age, sex, race, Tanner stage, physical activity, socioeconomic status, and body mass index, there were significant U-shaped trends for homeostasis model assessment of insulin resistance, leptin, and visceral adipose tissue (all Pquadratic < .05). A significant linear downward trend across tertiles of birth weight was observed for triglycerides (Plinear = .03). There were no differences in fasting glucose, blood pressure, total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, adiponectin, C-reactive protein, or subcutaneous abdominal adipose tissue across tertiles of birth weight.

CONCLUSIONS

Our data suggest that both low and high birth weights are associated with greater visceral adiposity and biomarkers implicated in insulin resistance and inflammation in adolescents.

Number of colony-forming unit-Hill colonies among children and teenagers with obesity, dyslipidemia and breastfeeding history

BACKGROUND AND AIMS

The number of colony-forming unit (CFU)-Hill colonies has been proposed as a biomarker of vascular function and cardiovascular risk in adults but information about its role in children is scarce. This study evaluates the associations between obesity, cardiovascular risk factors and breastfeeding history with the numbers of CFU-Hill colonies in a sample of young people.

METHODS AND RESULTS

We selected 49 children and teenagers between ages 10 and 17 (65.3% boys) from Mexican Health Care system. Physical activity and Anthropometric measures data were registered. CFU-Hill colonies were cultured from mononuclear cells obtained from venous blood. We detected inverse associations between the formation of CFU-Hill colonies and body mass index (BMI; β = -1.53; 95% confidence interval [CI], -1.92, -1.13), triglycerides (β = -0.26; 95%CI = -0.34, -0.18), total cholesterol (β = -0.13; 95%CI = -0.17, -0.08), Low Density Lipoprotein (LDL) (β = -0.20; 95%CI = -0.31, -0.09) and glucose (β = -0.37; 95%CI = -0.55, -0.18) using multivariate models. Breastfeeding duration showed a 1.46-colony increase for each month of breastfeeding (95%CI = 0.73, 2.18).

CONCLUSIONS

CFU-Hill colony-forming capacity in children and teenagers was inversely associated with obesity, dyslipidemia and high blood levels of glucose. In contrast a longer breastfeeding duration was directly associated with an increased number of CFU-Hill colonies. However these results must be confirmed with further studies. Our findings support the importance of promoting breastfeeding and monitoring nutritional and metabolic status at an early age to prevent chronic disease development.

Adiposity and Chronic Inflammation in Young Women Predict Inflammation during Normal Pregnancy in the Philippines

BACKGROUND

Rates of overweight and obesity are on the rise globally, and excess adipose tissue may contribute to elevations in inflammation during pregnancy, leading to pregnancy complications and adverse birth outcomes.

OBJECTIVE

The purpose of this study was to evaluate adiposity and inflammation in young women as predictors of inflammation in the third trimester of pregnancy in a community-based sample of healthy women.

METHODS

Female participants (24-30 y) in a prospective observational cohort study (Cebu Longitudinal Health and Nutrition Survey) were contacted between 2009 and 2014 to identify new pregnancies. A total of 309 women provided data from 409 pregnancies. An in-home interview was scheduled for the third trimester to collect pregnancy information, anthropometric measurements, and a blood sample. Circulating C-reactive protein (CRP) was measured with a high-sensitivity immunoassay. Data collected from assessments in 2005 and 2009 were used to assess body mass index (BMI) and CRP in young adulthood, before pregnancy. Robust regression models were implemented to evaluate BMI and CRP in young adulthood as predictors of pregnancy CRP.

RESULTS

Pre-pregnancy BMI was a stronger predictor of third-trimester circulating CRP than BMI in the third trimester. No association was found between pregnancy weight gain and CRP. Pre-pregnancy CRP was a significant predictor of CRP in pregnancy, independent of BMI.

CONCLUSIONS

Levels of overweight/obesity and inflammation in young adulthood, before pregnancy, are important predictors of inflammation in the third trimester of pregnancy. These results may have implications for addressing the growing concern about the contribution of obesity to adverse birth outcomes, and they suggest that factors that influence the regulation of inflammation, before pregnancy and independent of adiposity, may be important in shaping the inflammatory response to pregnancy.

Clinical applications of bioactive milk components

Milk represents a unique resource for translational medicine: It contains a rich pool of biologically active molecules with demonstrated clinical benefits. The ongoing characterization of the mechanistic process through which milk components promote development and immunity has revealed numerous milk-derived compounds with potential applications as clinical therapies in infectious and inflammatory disease, cancer, and other conditions. Lactoferrin is an effective antimicrobial and antiviral agent in high-risk patient populations and a potentially potent adjuvant to chemotherapy in lung cancer. Enteric nutrition formulas supplemented with transforming growth factor β, a milk cytokine, have been shown to promote remission in pediatric Crohn's disease. A number of milk glycans, including human milk oligosaccharides, show promise in preclinical studies as antimicrobial and anti-inflammatory agents. While active preclinical investigations of human milk may soon result in large-scale production of human milk molecules, bovine milk components in many instances represent a practical source of bioactive milk compounds for use in clinical trials. This review summarizes current efforts to translate the compounds derived from human and bovine milk into effective clinical therapies. These efforts suggest a common pathway for the translation of milk-derived compounds into clinical applications.

Trade-offs between acquired and innate immune defenses in humans

Immune defenses provide resistance against infectious disease that is critical to survival. But immune defenses are costly, and limited resources allocated to immunity are not available for other physiological or developmental processes. We propose a framework for explaining variation in patterns of investment in two important subsystems of anti-pathogen defense: innate (non-specific) and acquired (specific) immunity. The developmental costs of acquired immunity are high, but the costs of maintenance and activation are relatively low. Innate immunity imposes lower upfront developmental costs, but higher operating costs. Innate defenses are mobilized quickly and are effective against novel pathogens. Acquired responses are less effective against novel exposures, but more effective against secondary exposures due to immunological memory. Based on their distinct profiles of costs and effectiveness, we propose that the balance of investment in innate versus acquired immunity is variable, and that this balance is optimized in response to local ecological conditions early in development. Nutritional abundance, high pathogen exposure and low signals of extrinsic mortality risk during sensitive periods of immune development should all favor relatively higher levels of investment in acquired immunity. Undernutrition, low pathogen exposure, and high mortality risk should favor innate immune defenses. The hypothesis provides a framework for organizing prior empirical research on the impact of developmental environments on innate and acquired immunity, and suggests promising directions for future research in human ecological immunology.

Birth weight, early life course BMI, and body size change: Chains of risk to adult inflammation?

This paper examines how body size changes over the early life course to predict high sensitivity C-reactive protein in a U.S. based sample. Using three waves of the National Longitudinal Study of Adolescent Health (Add Health), we test the chronic disease epidemiological models of fetal origins, sensitive periods, and chains of risk from birth into adulthood. Few studies link birth weight and changes in obesity status over adolescence and early adulthood to adult obesity and inflammation. Consistent with fetal origins and sensitive periods hypotheses, body size and obesity status at each developmental period, along with increasing body size between periods, are highly correlated with adult CRP. However, the predictive power of earlier life course periods is mediated by body size and body size change at later periods in a pattern consistent with the chains of risk model. Adult increases in obesity had effect sizes of nearly 0.3 sd, and effect sizes from overweight to the largest obesity categories were between 0.3 and 1 sd. There was also evidence that risk can be offset by weight loss, which suggests that interventions can reduce inflammation and cardiovascular risk, that females are more sensitive to body size changes, and that body size trajectories over the early life course account for African American- and Hispanic-white disparities in adult inflammation.

Physiological mechanisms, behavioral and psychological factors influencing the transfer of milk from mothers to their young

This article is part of a Special Issue "Parental Care".Producing milk to support the growth of their young is a central element of maternal care in mammals. In spite of the facts that ecological constraints influence nursing frequency, length of time until weaning and the composition of milk, there is considerable similarity in the anatomy and physiology of milk production and delivery across mammalian species. Here we provide an overview of cross species variation in nursing patterns and milk composition as well as the mechanisms underlying mammary gland development, milk production and letdown. Not all women breastfeed their infants, thus in later sections we review studies of factors that facilitate or impede the initiation and duration of breastfeeding. The results of these investigations suggest that the decisions to initiate and maintain breastfeeding are influenced by an array of personal, social and biological factors. Finally, studies comparing the development of breastfed and formula fed infants as well as those investigating associations between breastfeeding, maternal health and mother/infant interaction are reviewed. Leading health agencies including the World Health Organization and CDC advocate breastfeeding for at least the first 6months postpartum. To achieve these rates will require not only institutional support but also a focus on individual mother/infant dyads and their experience.

Breastfeeding and language outcomes: A review of the literature

Many researchers have investigated the potential impact of breastfeeding in infancy on a child's subsequent development, but only a small subset of these studies considers language development and impairment. This paper reviews that literature, discussing postnatal neurodevelopment, potential mechanisms for dietary influences on communication outcomes, studies of typically developing children, and studies of children with communication concerns. For population based studies of language development, a modest but statistically robust relationship is seen across large samples that account for breastfeeding exclusivity. A similar protective relationship is seen in studies that evaluate the relationship between breastfeeding and language disorders; effect sizes are typically larger in these papers. Implications for researchers and service providers are reviewed.

LEARNING OUTCOMES

Readers will be able to describe possible mechanisms by which early diet might influence neurodevelopment. They will be able to describe the relationships observed between diet in infancy and language outcomes in large population-based studies, as well as the trends observed in studies of the relationship between infant diet and communication impairment.

Developmental origins of chronic inflammation: a review of the relationship between birth weight and C-reactive protein

PURPOSE

The developmental origins of adult disease hypothesis suggests that the intrauterine environment may program postnatal health outcomes through mechanisms such as chronic inflammation. The purpose of this article was to review the literature on the association between infant birth weight and C-reactive protein (CRP), markers of the fetal environment and inflammation, respectively.

METHODS

We used PubMed, Google Scholar, Web of Science, ScienceDirect, the citation lists of the reviewed literature, and recommendations from experts in the field to identify potential articles. Inclusion criteria for the studies, regardless of study design, included human subjects, documented or self-reported infant birth weight, and a minimum of one measurement of CRP (during childhood, adolescence, or adulthood).

RESULTS

Several studies demonstrated a statistically significant inverse association between birth weight and CRP in adulthood, although in many cases only after controlling for markers of current adiposity. No studies significantly linked birth weight to CRP in childhood or adolescence.

CONCLUSIONS

Longitudinal studies, including multigenerational studies, are needed to further understand whether adult CRP has origins in the fetal environment.

Breastfeeding over two years is associated with longer birth intervals, but not measures of growth or health, among children in Kilimanjaro, TZ

OBJECTIVES

Breastfeeding has been associated with numerous health and well-being benefits for both children and their mothers, including prolonging the birth interval to the subsequent sibling. The clearest associations between breastfeeding and health outcomes, per se, reflect exclusive breastfeeding in the first months of postnatal life and are most evident during infancy. Fewer studies explore the consequences of breastfeeding for multiple years. In this article, we ask whether breastfeeding for more than 2 years is associated with discernible health and well-being benefits to children.

METHODS

Data were collected from 315 children, aged 2 to 7, and their caretakers residing in Kilimanjaro, Tanzania. Basic demographic and health information was solicited, and anthropometric and blood markers of health were evaluated.

RESULTS

Our results indicate a strong positive relationship between breastfeeding for 2 or more years and interbirth interval, but little evidence for a relationship between prolonged breastfeeding and several indicators of child growth and health.

CONCLUSIONS

We suggest that these relationships may support the recently rekindled birth spacing hypothesis, positing selection for longer interbirth intervals, rather than, or in addition to, more direct health benefits associated with breastfeeding for 2 or more years. Our results may indicate attenuating health benefits associated with longer breastfeeding.