Early life influences on cardio-metabolic disease risk in aboriginal populations--what is the evidence? A systematic review of longitudinal and case-control studies

Determinants of Anishinabeck infant and early childhood growth trajectories in Northwestern Ontario, Canada: a cohort study

BACKGROUND

The Developmental Origins of Health and Disease (DOHaD) paradigm emphasizes the significance of early life factors for the prevention of chronic health conditions, like type 2 diabetes (T2DM) and obesity, which disproportionately affect First Nations communities in Canada. Despite increasing DOHaD research related to maternal health during pregnancy, early childhood growth patterns, and infant feeding practices with many populations, data from First Nations communities in Canada are limited. In partnership with Sandy Lake First Nation, the aims of this project were to characterize birthweights and growth patterns of First Nations infants/children over the first 6 years of life and to study the impact of maternal and infant social and behavioral factors on birthweight and growth trajectories.

METHODS

We recruited 194 families through community announcements and clinic visits. Infant/child length/height and weight were measured at 1 and 2 weeks; 1, 2, 6, 12, and 18 months; and 2, 3, 4, 5 and 6 years. Maternal and infant/child questionnaires captured data about health, nutrition, and social support. Weight-for-Age z-score (WAZ), Height-for-Age z-score (HAZ), and BMI-for-Age z-score (BAZ) were calculated using WHO reference standards and trajectories were analyzed using generalized additive models. Generalized estimating equations and logistic regression were used to determine associations between exposures and outcomes.

RESULTS

WAZ and BAZ were above the WHO mean and increased with age until age 6 years. Generalized estimating equations indicated that WAZ was positively associated with age (0.152; 95% CI 0.014, 0.29), HAZ was positively associated with birthweight (0.155; 95% CI 0.035, 0.275), and BAZ was positively associated with caregiver's BMI (0.049; 95% CI 0.004, 0.090). There was an increased odds of rapid weight gain (RWG) with exposure to gestational diabetes (OR: 7.47, 95% CI 1.68, 46.22). Almost 70% of parents initiated breastfeeding, and breastfeeding initiation was modestly associated with lower WAZ (-0.18; 95% CI -0.64, 0.28) and BAZ (-0.23; 95% CI -0.79, 0.34).

CONCLUSIONS

This work highlights early life factors that may contribute to T2DM etiology and can be used to support community and Indigenous-led prevention strategies.

The Marri Gudjaga project: a study protocol for a randomised control trial using Aboriginal peer support workers to promote breastfeeding of Aboriginal babies

BACKGROUND

Breastfeeding protects against a range of conditions in the infant, including sudden infant death syndrome (SIDS), diarrhoea, respiratory infections and middle ear infections [1, 2]. The World Health Organization (WHO) recommends exclusive breastfeeding until six months of age, with continued breastfeeding recommended for at least two years and other complementary nutritious foods [3]. The 2017-18 National Health Survey (NHS) and 2018-19 National Aboriginal and Torres Strait Islander Health Survey (NATSIHS) reported that the proportion of breastfeeding in Aboriginal and Torres Strait Islander infants (0-2 years) were less than half that of non-Indigenous infants (21.2% vs. 45%, respectively)[4]. There is a lack of research on interventions supporting Aboriginal women to breastfeed, identifying an evaluation gap related to peer support interventions to encourage exclusive breastfeeding in Aboriginal women.

METHODS

We will evaluate the effect of scheduled breastfeeding peer support for and by Aboriginal women, on breastfeeding initiation and the prevalence of exclusive breastfeeding. This MRFF (Medical Research Future Fund) funded project is designed as a single-blinded cluster randomised controlled trial recruiting six sites across New South Wales, Australia, with three sites being randomised to employ a peer support worker or undertaking standard care. Forty pregnant women will be recruited each year from each of the six sites and will be surveyed during pregnancy, at six weeks, four and six months postnatally with a single text message at 12 months to ascertain breastfeeding rates. In-depth interviews via an Indigenous style of conversation and storytelling called 'Yarning' will be completed at pre- and post-intervention with five randomly recruited community members and five health professionals at each site" [5]. Yarns will be audio recorded, transcribed, coded and thematic analysis undertaken. Health economic analysis will be completed to assess the health system incremental cost and effects of the breastfeeding intervention relative to usual care.

DISCUSSION

Evidence will be given on the effectiveness of Aboriginal peer support workers to promote the initiation and continuation of breastfeeding of Aboriginal babies. The findings of this study will provide evidence of effectiveness and cost-effectiveness of including peer support workers in postnatal care to promote breastfeeding practices.

TRIAL REGISTRATION

ACTRN12622001208796 The impact of breastfeeding peer support on nutrition of Aboriginal infants.

Potential Determinants of Cardio-Metabolic Risk among Aboriginal and Torres Strait Islander Children and Adolescents: A Systematic Review

Prevention initiatives during childhood and adolescence have great potential to address the health inequities experienced by Aboriginal and Torres Strait Islander (Indigenous) populations in Australia by targeting modifiable risk factors for cardio-metabolic diseases. We aimed to synthesize existing evidence about potential determinants of cardio-metabolic risk markers—obesity, elevated blood pressure, elevated blood glucose, abnormal lipids, or a clustering of these factors known as the metabolic syndrome (MetS)—for Indigenous children and adolescents. We systematically searched six databases for journal articles and three websites for relevant grey literature. Included articles (n = 47) reported associations between exposures (or interventions) and one or more of the risk markers among Indigenous participants aged 0–24 years. Data from 18 distinct studies about 41 exposure–outcome associations were synthesized (by outcome: obesity [n = 18]; blood pressure [n = 9]; glucose, insulin or diabetes [n = 4]; lipids [n = 5]; and MetS [n = 5]). Obesity was associated with each of the other cardio-metabolic risk markers. Larger birth size and higher area-level socioeconomic status were associated with obesity; the latter is opposite to what is observed in the non-Indigenous population. There were major gaps in the evidence for other risk markers, as well as by age group, geography, and exposure type. Screening for risk markers among those with obesity and culturally appropriate obesity prevention initiatives could reduce the burden of cardio-metabolic disease.

Recent Experimental Studies of Maternal Obesity, Diabetes during Pregnancy and the Developmental Origins of Cardiovascular Disease

Globally, cardiovascular disease remains the leading cause of death. Most concerning is the rise in cardiovascular risk factors including obesity, diabetes and hypertension among youth, which increases the likelihood of the development of earlier and more severe cardiovascular disease. While lifestyle factors are involved in these trends, an increasing body of evidence implicates environmental exposures in early life on health outcomes in adulthood. Maternal obesity and diabetes during pregnancy, which have increased dramatically in recent years, also have profound effects on fetal growth and development. Mounting evidence is emerging that maternal obesity and diabetes during pregnancy have lifelong effects on cardiovascular risk factors and heart disease development. However, the mechanisms responsible for these observations are unknown. In this review, we summarize the findings of recent experimental studies, showing that maternal obesity and diabetes during pregnancy affect energy metabolism and heart disease development in the offspring, with a focus on the mechanisms involved. We also evaluate early proof-of-concept studies for interventions that could mitigate maternal obesity and gestational diabetes-induced cardiovascular disease risk in the offspring.

Developmental origins of disease highlight the immediate need for expanded access to comprehensive prenatal care

The prenatal environment plays a critical role in shaping fetal development and ultimately the long-term health of the child. Here, we present data linking prenatal health, via maternal nutrition, comorbidities in pregnancy (e.g., diabetes, hypertension), and infectious and inflammatory exposures, to lifelong health through the developmental origins of disease framework. It is well-established that poor maternal health puts a child at risk for adverse outcomes in the first 1,000 days of life, yet the full health impact of the in utero environment is not confined to this narrow window. The developmental origins of disease framework identifies cognitive, neuropsychiatric, metabolic and cardiovascular disorders, and chronic diseases in childhood and adulthood that have their genesis in prenatal life. This perspective highlights the enormous public health implications for millions of pregnancies where maternal care, and therefore maternal health and fetal health, is lacking. Despite near universal agreement that access to antenatal care is a priority to protect the health of women and children in the first 1,000 days of life, insufficient progress has been achieved. Instead, in some regions there has been a political shift toward deprioritizing maternal health, which will further negatively impact the health and safety of pregnant people and their children across the lifespan. In this article we argue that the lifelong health impact attributed to the perinatal environment justifies policies aimed at improving access to comprehensive antenatal care globally.

Pregnancy and birth characteristics of Aboriginal twins in two Australian states: a data linkage study

Introduction

Perinatal outcomes for singleton pregnancies are poorer, on average, for Aboriginal people than non-Aboriginal people, but little is known about Aboriginal multifetal pregnancies. Yet multifetal pregnancies and births are often more complicated and have poorer outcomes than singleton pregnancies. We describe the pregnancies, births and perinatal outcomes for Aboriginal twins born in Western Australia (WA) and New South Wales (NSW) with comparisons to Aboriginal singletons in both states and to non-Aboriginal births in NSW.

Materials and methods

Whole-population birth records and birth and death registrations were linked for all births during 2000–2013 (WA) and 2002–2008 (NSW). Hospital records and the WA Register of Developmental Anomalies - Cerebral Palsy were linked for all WA births and hospital records for a subset of NSW births. Descriptive statistics are reported for maternal and child demographics, maternal health, pregnancy complications, births and perinatal outcomes.

Results

Thirty-four thousand one hundred twenty-seven WA Aboriginal, 32,352 NSW Aboriginal and 601,233 NSW non-Aboriginal births were included. Pregnancy complications were more common among mothers of Aboriginal twins than Aboriginal singletons (e.g. 17% of mothers of WA twins had hypertension/pre-eclampsia/eclampsia vs 8% of mothers of singletons) but similar to mothers of NSW non-Aboriginal twins. Most Aboriginal twins were born in a principal referral, women’s or large public hospital. The hospitals were often far from the mother’s home (e.g. 31% of mothers of WA Aboriginal twins gave birth at hospitals located more than 3 h by road from their home). Outcomes were worse for Aboriginal liveborn twins than Aboriginal singletons and non-Aboriginal twins (e.g. 58% of NSW Aboriginal twins were preterm compared to 9% of Aboriginal singletons and 49% non-Aboriginal twins).

Conclusions

Mothers of Aboriginal twins faced significant challenges during the pregnancy, birth and the postnatal period in hospital and, in addition to accessible specialist medical care, these mothers may need extra practical and psychosocial support throughout their journey.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03945-9.

Protocol for a scoping review of the qualitative literature on Indigenous infant feeding experiences

INTRODUCTION

Prudent infant nutrition, including exclusive breastfeeding to 6 months, is essential for optimal short-term and long-term health. Quantitative research to date has documented that many Indigenous communities have lower breastfeeding rates than the general population and that this gap in breastfeeding initiation and maintenance may have an important impact on chronic disease risk later in life. However, there are critical knowledge gaps in the literature regarding factors that influence infant feeding decisions. Qualitative research on infant feeding experiences provides a broader understanding of the challenges that Indigenous caregivers encounter, and insights provided by this approach are essential to identify research gaps, community engagement strategies, and programme and policy development. The objective of this review is to summarise the qualitative literature that describes breastfeeding and other infant feeding experiences of Indigenous caregivers.

METHODS AND ANALYSIS

This scoping review will follow guidelines from Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews, the Joanna Briggs Institute and the methodological framework from Arksey and O'Malley. In October 2020, we will conduct an electronic database search using Medline, Embase, The Cumulative Index to Nursing & Allied Health Literature (CINAHL), PsycINFO, and Scopus, and will focus on qualitative studies. Publications that have a focus on infant feeding in Canada, the USA, Australia and New Zealand, and the Indigenous caregiver experience from the caregiver perspective, will be included. We will conduct a grey literature search using Indigenous Studies Portal, country-specific browser searches, and known government, association, and community websites/reports. We will map themes and concepts of the publications, including study results and methodologies, to identify research gaps, future directions, challenges and best practices in this topic area.

ETHICS AND DISSEMINATION

Ethical approval is not required for this review as no unpublished primary data will be included. The results of this review will be shared through peer-reviewed publications and conference presentations. This protocol is registered through the Open Science Framework (osf.io/4su79).

Early life predictors of development of blood pressure from childhood to adulthood: Evidence from a 30-year longitudinal birth cohort study

BACKGROUND AND AIMS

The early life predictors of changes in the blood pressures of offspring between childhood and young adulthood have not been well defined. Thus, this study aimed to determine the life course association of offspring's blood pressure with prenatal and early infancy lifestyle, and other factors taking advantage of a large community-based, longitudinal study of a birth cohort in Australia - the MUSP study.

METHODS

The systolic and diastolic blood pressure (SBP, DBP) was measured for 3793, 3782, 2628 and 1780 offspring of the Australian longitudinal cohort study at 5, 14, 21 and 30 years of their age, respectively. Individual PP and mean arterial pressure (MAP) was equated, and Generalized Estimating Equations with time (age) and predictor interaction modelling were performed.

RESULTS

Blood pressures of the offspring increased significantly between 5 and 30 years. Early life factors such as pre-pregnancy overweight/obesity, and hypertensive disorder in pregnancy were significantly positively associated, and duration of gestation and pre-pregnancy thinness of the mothers negatively associated with this life course increase in the offspring's blood pressure. Rapid increase in body weight from birth to 5 years had a strong association with increasing blood pressures components throughout their life course.

CONCLUSIONS

Several maternal pre-pregnancy and pregnancy factors along with the early life growth characteristics of offspring are important predictors of increase in blood pressure of the offspring from their childhood to adulthood.

Early life risk and resiliency factors and their influences on developmental outcomes and disease pathways: a rapid evidence review of systematic reviews and meta-analyses

The Developmental Origins of Health and Disease (DOHaD) framework aims to understand how environmental exposures in early life shape lifecycle health. Our understanding and the ability to prevent poor health outcomes and enrich for resiliency remain limited, in part, because exposure-outcome relationships are complex and poorly defined. We, therefore, aimed to determine the major DOHaD risk and resilience factors. A systematic approach with a 3-level screening process was used to conduct our Rapid Evidence Review following the established guidelines. Scientific databases using DOHaD-related keywords were searched to capture articles between January 1, 2009 and April 19, 2019. A final total of 56 systematic reviews/meta-analyses were obtained. Studies were categorized into domains based on primary exposures and outcomes investigated. Primary summary statistics and extracted data from the studies are presented in Graphical Overview for Evidence Reviews diagrams. There was substantial heterogeneity within and between studies. While global trends showed an increase in DOHaD publications over the last decade, the majority of data reported were from high-income countries. Articles were categorized under six exposure domains: Early Life Nutrition, Maternal/Paternal Health, Maternal/Paternal Psychological Exposure, Toxicants/Environment, Social Determinants, and Others. Studies examining social determinants of health and paternal influences were underrepresented. Only 23% of the articles explored resiliency factors. We synthesized major evidence on relationships between early life exposures and developmental and health outcomes, identifying risk and resiliency factors that influence later life health. Our findings provide insight into important trends and gaps in knowledge within many exposures and outcome domains.

Diabetes during pregnancy and birthweight trends among Aboriginal and non-Aboriginal people in the Northern Territory of Australia over 30 years

Background

Early-life risk factors, including maternal hyperglycaemia and birthweight, are thought to contribute to the high burden of cardiometabolic disease experienced by Indigenous populations. We examined rates of pre-existing diabetes in pregnancy, gestational diabetes mellitus (GDM) and extremes of birthweight over three decades in the Northern Territory (NT) of Australia.

Methods

We performed a retrospective cohort analysis of the NT Perinatal Data Collection from 1987 to 2016, including all births >20 weeks gestation, stratified by maternal Aboriginal identification. Key outcomes were annual rates of pre-existing diabetes, GDM, small-for-gestational-age, large-for-gestational-age, low birthweight (<2500 g), and high birthweight (>4000 g). Logistic regression was used to assess trends and interactions.

Findings

109 349 babies were born to 64 877 mothers, 36% of whom identified as Aboriginal ethnicity. Among Aboriginal women, rates of GDM and pre-existing diabetes, respectively, were 3 · 4% and 0 · 6% in 1987 and rose to 13% and 5 · 7% in 2016 (both trends p<0 · 001). Among non-Aboriginal women, rates of GDM increased from 1 · 9% in 1987 to 11% in 2016 (p<0 · 001), while pre-existing diabetes was uncommon (≤0 · 7% throughout). Rates of small-for-gestational-age decreased, while rates of large-for-gestational-age and high birthweight increased in both groups (all trends p<0 · 001). Multivariable modelling suggests that hyperglycaemia was largely responsible for the growing rate of large-for-gestational-age births among Aboriginal women.

Interpretation

The burden of hyperglycaemia in pregnancy has grown substantially in the NT over three decades and is impacting birthweight trends. The prevalence of pre-gestational diabetes in Aboriginal women is among the highest in the world.

Funding

Diabetes Australia Research Program.

Review of online breastfeeding information for Aboriginal and Torres Strait Islander women

BACKGROUND

Breastfeeding provides the healthiest start to life, but breastfeeding rates amongst Aboriginal and Torres Strait Islanders is lower than non-Indigenous women.

AIM

To assess the accuracy, quality and appropriate presentation of online breastfeeding information for Aboriginal and Torres Strait Islander women in Australia.

METHODS

An online search conducted in Google, Bing and Yahoo search engines to identify any breastfeeding websites that provided information for Aboriginal and Torres Strait Islander women. Relevant websites were evaluated against: a) National Health and Medical Research Council clinical guidelines, b) the quality of health information on the Internet by using DISCERN instrument, and c) appropriate key design features for Aboriginal and Torres Strait Islander women.

RESULTS

The search located 348 sites with 31 being eligible for inclusion. Websites from governmental organizations had the highest accuracy while YouTube videos had the lowest accuracy. Three quarters (74%, n=23) of sites incorporated the national clinical guidelines adequately, and most of the sites (77.8%, n=24) were considered high quality. Only 23% (n=7) of sites had sufficient key design features appropriate for Aboriginal and Torres Strait Islander women. Four websites were considered exemplary for their accuracy, quality and cultural appropriateness of information for Aboriginal and Torres Strait Islander women.

CONCLUSION

Some websites are tailored to provide breastfeeding information and support to Aboriginal and Torres Strait Islander women. However, only a few contain culturally appropriate key design features. Further participatory action research is required to design online platforms for women from different cultural backgrounds that take into account cultural principles, beliefs and values.

Maternal betaine status, but not that of choline or methionine, is inversely associated with infant birth weight

Maternal one-carbon metabolism during pregnancy is crucial for fetal development and programming by DNA methylation. However, evidence on one-carbon biomarkers other than folate is lacking. We, therefore, investigated whether maternal plasma methyl donors, that is, choline, betaine and methionine, are associated with birth outcomes. Blood samples were obtained from 115 women during gestation (median 26·3 weeks, 90 % range 22·7-33·0 weeks). Plasma choline, betaine, methionine and dimethylglycine were measured using HPLC-tandem MS. Multivariate linear and logistic regression models were used to estimate the association between plasma biomarkers and birth weight, birth length, the risk of small-for-gestational-age and large-for-gestational-age (LGA). Higher level of maternal betaine was associated with lower birth weight (-130·3 (95 % CI -244·8, -15·9) per 1 sd increment for log-transformed betaine). Higher maternal methionine was associated with lower risk of LGA, and adjusted OR, with 95 % CI for 1 sd increase in methionine concentration was 0·44 (95 % CI 0·21, 0·89). Stratified analyses according to infant sex or maternal plasma homocysteine status showed that reduction in birth weight in relation to maternal betaine was only limited to male infants or to who had higher maternal homocysteine status (≥5·1 µmol/l). Higher maternal betaine status was associated with reduced birth weight. Maternal methionine was inversely associated with LGA risk. These findings are needed to be replicated in future larger studies.

Health outcomes for Australian Aboriginal and Torres Strait Islander children born preterm, low birthweight or small for gestational age: A nationwide cohort study

Objective

To examine health outcomes in Australian Aboriginal and Torres Strait Islander children experiencing perinatal risk and identify protective factors in the antenatal period.

Methods

Baby/Child cohorts of the Longitudinal Study of Indigenous Children, born 2001–2008, across four annual surveys (aged 0–8 years, N = 1483). Children with ‘mild’ and ‘moderate-to-high’ perinatal risk were compared to children born normal weight at term for maternal-rated global health and disability, and body-mass-index measured by the interviewer.

Results

Almost one third of children had experienced mild (22%) or moderate-to-high perinatal risk (8%). Perinatal risk was associated with lower body-mass-index z-scores (regression coefficients adjusted for pregnancy and environment factors: mild = -0.21, 95% CI = -0.34, -0.07; moderate-to-high = -0.42, 95% CI = -0.63, -0.21). Moderate-to-high perinatal risk was associated with poorer global health, with associations becoming less evident in models adjusted for pregnancy and environment factors; but not evident for disability. A range of protective factors, including cultural-based resilience and smoking cessation, were associated with lower risk of adverse outcomes.

Conclusions

Perinatal risks are associated with Australian Aboriginal and Torres Strait children experiencing adverse health particularly lower body weight. Cultural-based resilience and smoking cessation may be two modifiable pathways to ameliorating health problems associated with perinatal risk.

Nutritional dual burden in Indigenous young adults: The geographical differential

OBJECTIVE

Nutritional dual burden is defined as the coexistence of underweight and overweight in the same population. We report the rates of nutritional dual burden in Indigenous young men and women in the Northern Territory. Additionally, we examine the impact geographical area has on these rates.

DESIGN

Cross-sectional data obtained from the longitudinal Aboriginal Birth Cohort Study.

SETTING

Participants residing in over 40 urban and remote communities across the Top End of the Northern Territory.

PARTICIPANTS

Young adults aged 23-28 years; urban (n = 99) and remote (n = 316).

MAIN OUTCOME MEASURE(S)

Anthropometric data was directly collected using standardised methods. Underweight was defined as BMI ≤ 18.5 kg/m² and overweight/obese as body mass index ≥ 25 kg/m² . Remote residency was categorised by established shires/regions (Vic/Daly, Arnhem and Tiwi).

RESULTS

Significantly higher levels of underweight were seen in remote participants, compared to urban participants, irrespective of sex. Further differences were seen by regions, with the highest rates seen in Vic/Daly, compared to Arnhem and Tiwi. Higher rates of overweight/obesity were found in urban participants, compared to remote. The levels of overweight/obesity varied, depending on region of residence.

CONCLUSION

Underweight and overweight patterns coexist in Indigenous young adults, with variation across geographical regions. Health programs need to take this dual nutritional burden into consideration to avoid worsening the severity of underweight, whilst reducing levels of overweight.

Musculoskeletal health of Indigenous Australians

INTRODUCTION

Research on non-communicable diseases (NCD) in Indigenous Australians has mostly focused on diabetes mellitus and chronic kidney or cardiovascular disease. Osteoporosis, characterised by low bone mass and structural deterioration of bone tissue, and sarcopenia, the age-related loss of muscle mass and strength, often co-exist with these common NCDs-the combination of which will disproportionately increase bone fragility and fracture risk and negatively influence cortical and trabecular bone. Furthermore, the social gradient of NCDs, including osteoporosis and fracture, is well-documented, meaning that specific population groups are likely to be at greater risk of poorer health outcomes: Indigenous Australians are one such group.

PURPOSE

This review summarises the findings reported in the literature regarding the muscle and bone health of Indigenous Australians.

FINDINGS

There are limited data regarding the musculoskeletal health of Indigenous Australians; however, areal bone mineral density (aBMD) measured by dual-energy X-ray absorptiometry (DXA) is reported to be greater at the hip compared to non-Indigenous Australians. Falls are the leading cause of injury-related hospitalisations in older Australians, particularly Indigenous Australians, with a great proportion suffering from fall-related fractures. Despite sparse data, it appears that Indigenous men and women have a substantially higher risk of hip fracture at a much younger age compared to non-Indigenous Australians.

CONCLUSION

Data on more detailed musculoskeletal health outcomes are required in Indigenous Australians to better understand fracture risk and to formulate evidence-based strategies for fracture prevention and to minimise the risk of falls.

Influence of maternal adiposity, preterm birth and birth weight centiles on early childhood obesity in an Indigenous Australian pregnancy-through-to-early-childhood cohort study

Childhood obesity rates are higher among Indigenous compared with non-Indigenous Australian children. It has been hypothesized that early-life influences beginning with the intrauterine environment predict the development of obesity in the offspring. The aim of this paper was to assess, in 227 mother-child dyads from the Gomeroi gaaynggal cohort, associations between prematurity, Gestation Related-Optimal Weight (GROW) centiles, maternal adiposity (percentage body fat, visceral fat area), maternal non-fasting plasma glucose levels (measured at mean gestational age of 23.1 weeks) and offspring BMI and adiposity (abdominal circumference, subscapular skinfold thickness) in early childhood (mean age 23.4 months). Maternal non-fasting plasma glucose concentrations were positively associated with infant birth weight (P=0.005) and GROW customized birth weight centiles (P=0.008). There was a significant association between maternal percentage body fat (P=0.02) and visceral fat area (P=0.00) with infant body weight in early childhood. Body mass index (BMI) in early childhood was significantly higher in offspring born preterm compared with those born at term (P=0.03). GROW customized birth weight centiles was significantly associated with body weight (P=0.01), BMI (P=0.007) and abdominal circumference (P=0.039) at early childhood. Our findings suggest that being born preterm, large for gestational age or exposed to an obesogenic intrauterine environment and higher maternal non-fasting plasma glucose concentrations are associated with increased obesity risk in early childhood. Future strategies should aim to reduce the prevalence of overweight/obesity in women of child-bearing age and emphasize the importance of optimal glycemia during pregnancy, particularly in Indigenous women.

Placental surface area mediates the association between FGFR2 methylation in placenta and full-term low birth weight in girls

Background

Fibroblast growth factor receptor 2 (FGFR2) gene encodes a protein of the fibroblast growth factor receptor family. FGFR2 gene expression is associated with the regulation of implantation process of placenta which plays a vital role in fetal growth. DNA methylation is widely known as a mechanism of fetal growth. However, it is unclear whether and how DNA methylation of FGFR2 gene in the placenta is associated with full-term low birth weight. This case-control study aims to explore the links between FGFR2 methylation in placenta and full-term low birth weight and to further examine the mediation effect of placental surface area on this association.

Results

We conducted analyses for each of the five valid CpG sites at FGFR2 in 165 mother-baby pairs (86 FT-LBW vs. 79 FT-NBW) and found that per one standard deviation increase in the DNA methylation of CpG 11 at FGFR2 was associated with 1.64-fold higher risk of full-term low birth weight (OR = 1.64, 95% CI = [1.07, 2.52]) and 0.18 standard deviation decrease in placental surface area (β = - 0.18; standard error = 0.08, p = 0.02). The mediation effect of placental surface area on the association between DNA methylation and full-term low birth weight was significant in girls (OR = 1.38, 95% CI = [1.05, 1.80]) but not in boys. The estimated mediation proportion was 48.38%.

Conclusion

Our findings suggested that placental surface area mediated the association between DNA methylation of FGFR2 in placenta and full-term low birth weight in a sex-specific manner. Our study supported the importance of placental epigenetic changes in placental development and fetal growth.

[Nutritional Status of Japanese Women of Childbearing Age and the Ideal Weight Range for Pregnancy]

According to the recent 2015 Nutrition Survey, the prevalence of being underweight (Body Mass Index, BMI <18.5 kg/m²) among women in their 20s is 22.3%. Women of childbearing age tend to have a lower intake of protein and their total energy intake is lower than the requirements established by the 2015 Dietary Reference Intakes for Japanese. There is a growing body of evidence showing that underweight women tend to bear small babies and that these babies have an increased risk of diabetes or cancer in their adulthood. In order to prevent Japanese women from bearing small babies, the literature has suggested that women of childbearing age should be encouraged to remain at a normal weight before pregnancy. For optimal weight gain during pregnancy, existing guidelines recommend different ranges of weight gain based on prepregnancy BMI. Owing to the absence of official GWG recommendations in Asian countries, including China and Taiwan, the US Institute of Medicine (IOM) guidelines are generally followed. However, Asian women are smaller and experience lower weight gains; therefore, excessive weight gain may lead to harmful events including macrosomia, preterm birth, preeclampsia, gestational diabetes, pregnancy-induced hypertension, and short- and long-term postpartum weight retention. Thus, an accurate GWG range should be determined for Asian women. We introduce one epidemiological study in which the optimal weight gain range was investigated by analyzing receiver-operating characteristic curves together with potential research ideas in this field with the aim of encouraging young researchers to solve this public health problem affecting mothers and children.

The Barker hypothesis confirmed: association of low birth weight with all-cause natural deaths in young adult life in a remote Australian Aboriginal community

Barker et al. proposed that low birth weight predisposes to higher death rates in adult life. We previously confirmed this fact in a cohort of young adults who were born in a remote Australian Aboriginal community between 1956 and 1985. We now present data in these same people with four more years of follow-up and a greater number of deaths. The fates of participants were documented from age 15 years until death, start of dialysis, or until the end of 2010 and causes of death were derived from clinic narratives and dialysis records. Rates of natural deaths were compared by birth cohorts and birth weight, and hazard ratios were calculated using Cox proportional hazards methods, by birth weight and adjusted for birth cohort and sex. Over follow-up of 19,661 person-years, 61 people died of natural causes between age 15 and the censor date. Low birth weights (&lt;2.5 kg) were associated with higher rates of natural death, with HR (95% CI) 1.76 (1.1-2.9, P=0.03), after adjustment for year of birth and sex. The effect was particularly prominent for deaths at &lt;41 years of age, and with deaths from respiratory conditions/sepsis and unusual causes. A predisposing effect of low birth weight on adult deaths was confirmed. This phenomenon, occurring in the context of dramatically improved survivals of lower birth weight infants and children since the early 1960s, helps explain the current epidemic of chronic disease in Aboriginal people. Birth weights continue to improve, so excess deaths from this source should progressively be minimized.

Does Indigenous health research have impact? A systematic review of reviews

Background

Aboriginal and Torres Strait Islander Australians (hereafter respectfully Indigenous Australians) claim that they have been over-researched without corresponding research benefit. This claim raises two questions. The first, which has been covered to some extent in the literature, is about what type(s) of research are likely to achieve benefits for Indigenous people. The second is how researchers report the impact of their research for Indigenous people. This systematic review of Indigenous health reviews addresses the second enquiry.

Methods

Fourteen electronic databases were systematically searched for Indigenous health reviews which met eligibility criteria. Two reviewers assessed their characteristics and methodological rigour using an a priori protocol. Three research hypotheses were stated and tested: (1) reviews address Indigenous health priority needs; (2) reviews adopt best practice guidelines on research conduct and reporting in respect to methodological transparency and rigour, as well as acceptability and appropriateness of research implementation to Indigenous people; and (3) reviews explicitly report the incremental impacts of the included studies and translation of research. We argue that if review authors explicitly address each of these three hypotheses, then the impact of research for Indigenous peoples’ health would be explicated.

Results

Seventy-six reviews were included; comprising 55 journal articles and 21 Australian Government commissioned evidence review reports. While reviews are gaining prominence and recognition in Indigenous health research and increasing in number, breadth and complexity, there is little reporting of the impact of health research for Indigenous people. This finding raises questions about the relevance of these reviews for Indigenous people, their impact on policy and practice and how reviews have been commissioned, reported and evaluated.

Conclusions

The findings of our study serve two main purposes. First, we have identified knowledge and methodological gaps in documenting Indigenous health research impact that can be addressed by researchers and policy makers. Second, the findings provide the justification for developing a framework allowing researchers and funding bodies to structure future Indigenous health research to improve the reporting and assessment of impact over time.

Electronic supplementary material

The online version of this article (doi:10.1186/s12939-017-0548-4) contains supplementary material, which is available to authorized users.

Tissue differences in DNA methylation changes at AHRR in full term low birth weight in maternal blood, placenta and cord blood in Chinese

INTRODUCTION

Very few study addressed the relationship between Aryl-hydrocarbon receptor repressor (AHRR) DNA methylation and low birth weight, especially in multiple tissues of mother-infant pairs. In this study, we aimed to investigate AHRR DNA methylation modification in cord blood, placenta and maternal blood between full term low birth weight (FT-LBW) and full term normal birth weight (FT-NBW) newborns.

METHODS

We enrolled 90 FT-LBW and 90 FT-NBW mother-infant pairs, of which all placenta and cord blood samples were collected while 45 maternal blood samples of each group were collected. We measured AHRR DNA methylation (Chr5: 373013-373606) using Sequenom MassARRAY, and assessed associations between AHRR DNA methylation and FT-LBW using logistic regression adjusting for maternal age, education, family income, delivery mode, and passive smoking.

RESULTS

FT-LBW babies had 3% lower methylation at Chr5: 373378 (CpG 13) in cord blood, and 4-9% higher methylation levels at Chr5: 373315, 373378, 373423, 373476 and 373490/373494 (CpG 10; 13; 15; 16; 17/18 respectively) in maternal blood, comparing with FT-NBW. The methylation of Chr5: 373378 (CpG 13) remained significant association with FT-LBW both in cord blood (OR = 0.90; 95% CI: 0.82, 0.98) and maternal blood (OR = 1.14; 95% CI: 1.04, 1.25) further adjusting for each other in the same model. We observed no significant difference at any CpG sites in placenta.

DISCUSSION

AHRR DNA methylation of cord and maternal blood might be independently associated with FT-LBW in different ways.

Protein-restricted diet during pregnancy after insemination alters behavioral phenotypes of the progeny

Background

Epidemiological studies suggest that hyponutrition during the fetal period increases the risk of mental disorders such as attention deficit hyperactivity disorder and autism-spectrum disorder, which has been experimentally supported using animal models. However, previous experimental hyponutrition or protein-restricted (PR) diets affected stages other than the fetal stage, such as formation of the egg before insemination, milk composition during lactation, and maternal nursing behavior.

Results

We conducted in vitro fertilization and embryo transfer in mice and allowed PR diet and folic acid-supplemented PR diet to affect only fetal environments. Comprehensive phenotyping of PR and control-diet progenies showed moderate differences in fear/anxiety-like, novelty-seeking, and prosocial behaviors, irrespective of folic-acid supplementation. Changes were also detected in gene expression and genomic methylation in the brain.

Conclusions

These results suggest that epigenetic factors in the embryo/fetus influence behavioral and epigenetic phenotypes of progenies. Significant epigenetic alterations in the brains of the progenies induced by the maternal-protein restriction were observed in the present study. To our knowledge, this is first study to evaluate the effect of maternal hyponutrition on behavioral phenotypes using reproductive technology.

Electronic supplementary material

The online version of this article (doi:10.1186/s12263-016-0550-2) contains supplementary material, which is available to authorized users.

The early life origin theory in the development of cardiovascular disease and type 2 diabetes

Life expectancy has been examined from a variety of perspectives in recent history. Epidemiology is one perspective which examines causes of morbidity and mortality at the population level. Over the past few 100 years there have been dramatic shifts in the major causes of death and expected life length. This change has suffered from inconsistency across time and space with vast inequalities observed between population groups. In current focus is the challenge of rising non-communicable diseases (NCD), such as cardiovascular disease and type 2 diabetes mellitus. In the search to discover methods to combat the rising incidence of these diseases, a number of new theories on the development of morbidity have arisen. A pertinent example is the hypothesis published by David Barker in 1995 which postulates the prenatal and early developmental origin of adult onset disease, and highlights the importance of the maternal environment. This theory has been subject to criticism however it has gradually gained acceptance. In addition, the relatively new field of epigenetics is contributing evidence in support of the theory. This review aims to explore the implication and limitations of the developmental origin hypothesis, via an historical perspective, in order to enhance understanding of the increasing incidence of NCDs, and facilitate an improvement in planning public health policy.

Hypertension

Raised blood pressure is the biggest single contributor to the global burden of disease and to global mortality. The numbers of people affected and the prevalence of high blood pressure worldwide are expected to increase over the next decade. Preventive strategies are therefore urgently needed, especially in less developed countries, and management of hypertension must be optimised. Genetic advances in some rare causes of hypertension have been made lately, but the aggregate effect on blood pressure of all the genetic loci identified to date is small. Hence, intervention on key environmental determinants and effective implementation of trial-based therapies are needed. Three-drug combinations can control hypertension in about 90% of patients but only if resources allow identification of patients and drug delivery is affordable. Furthermore, assessment of optimal drug therapy for each ethnic group is needed.

Low birthweight increases risk for cardiovascular disease hospitalisations in a remote Indigenous Australian community--a prospective cohort study

OBJECTIVES

To investigate the association between low birthweight (LBW; <2,500 grams) and cardiovascular disease (CVD) hospitalisations in adult life in a remote Indigenous Australian community.

METHODS

This was a prospective cohort of 852 participants with recorded birthweight using community-wide health screening examinations conducted between 1992 and 1999 and hospitalisation records up to 2012. Cox proportional hazard models assessed the association between LBW and hypertension, major CVD (heart failure, myocardial infarction and stroke) and any CVD hospitalisations.

RESULTS

There were 236 participants (28%) who had a low birthweight. The LBW group had a higher risk of developing any CVD (HR = 1.43, 95%CI 1.01-2.03), major CVD (HR = 1.51, 95%CI 0.93-2.47) and hypertension (HR = 1.83, 95%CI 1.09-2.96) than the normal birthweight (NBW) group (≥2,500 g). Women with LBW had more than 2.6 times the risk of a hospitalisation associated with hypertension compared to their NBW counterparts (HR = 2.61, 95%CI 1.38-4.93), but this relationship was not seen in men.

CONCLUSIONS AND IMPLICATIONS

LBW increased the risk of cardiovascular disease hospitalisations in adult life in this group. Further CVD prevention initiatives should continue to include LBW as a key predictor of CVD in this community. The mechanisms of gender influence on the hypertension relationship are unknown and require further investigation in indigenous populations worldwide.

Early Life Predictors of Increased Body Mass Index among Indigenous Australian Children

Aboriginal and Torres Strait Islander Australians are more likely than non-Indigenous Australians to be obese and experience chronic disease in adulthood--conditions linked to being overweight in childhood. Birthweight and prenatal exposures are associated with increased Body Mass Index (BMI) in other populations, but the relationship is unclear for Indigenous children. The Longitudinal Study of Indigenous Children is an ongoing cohort study of up to 1,759 children across Australia. We used a multilevel model to examine the association between children's birthweight and BMI z-score in 2011, at age 3-9 years, adjusted for sociodemographic and maternal factors. Complete data were available for 682 of the 1,264 children participating in the 2011 survey; we repeated the analyses in the full sample with BMI recorded (n=1,152) after multilevel multiple imputation. One in ten children were born large for gestational age, and 17% were born small for gestational age. Increasing birthweight predicted increasing BMI; a 1-unit increase in birthweight z-score was associated with a 0.22-unit (95% CI:0.13, 0.31) increase in childhood BMI z-score. Maternal smoking during pregnancy was associated with a significant increase (0.25; 95% CI:0.05, 0.45) in BMI z-score. The multiple imputation analysis indicated that our findings were not distorted by biases in the missing data. High birthweight may be a risk indicator for overweight and obesity among Indigenous children. National targets to reduce the incidence of low birthweight which measure progress by an increase in the population's average birthweight may be ignoring a significant health risk; both ends of the spectrum must be considered. Interventions to improve maternal health during pregnancy are the first step to decreasing the prevalence of high BMI among the next generation of Indigenous children.

Somatic diseases and conditions before the first diagnosis of schizophrenia: a nationwide population-based cohort study in more than 900 000 individuals

OBJECTIVE

Schizophrenia is associated with excess physical comorbidity. Yet, to our knowledge, large studies are lacking on the associations with somatic diseases before the onset of schizophrenia. The authors conducted a nationwide study of the full spectrum of treated somatic diseases before the first diagnosis of schizophrenia.

METHOD

Nationwide sample of the Danish population consisting of singletons (n = 954351) born 1977-1993 and followed from birth to 2009, during which period 4371 developed schizophrenia. Somatic diagnoses at all general hospital contacts (admitted or outpatient care at a somatic hospital) from 1977 to 2009 were used as exposures. The incidence rate ratio (IRR) of schizophrenia was calculated using Poisson regression adjusted for confounders.

RESULTS

Among the 4371 persons who developed schizophrenia from 1992 to 2009, a total of 4180 (95.6%) persons had a previous somatic hospital contact. A history of any somatic hospital contact was associated with an elevated risk of schizophrenia (IRR = 2.04, 95% CI = 1.77-2.37). A wide range of somatic diseases and conditions were associated with an increased risk of schizophrenia, including epilepsy (IRR = 2.26, 95% CI = 1.93-2.62), nutritional or metabolic disorders (IRR = 1.57, 95% CI = 1.39-1.77), circulatory system diseases (IRR = 1.63, 95% CI= 1.38-1.92), and brain injury (IRR = 1.58, 95% CI = 1.45-1.72).

CONCLUSIONS

A wide range of potential etiological factors could have contributed to the observed associations, including genetic or physiological overlaps between conditions, and interacting immunological, behavioral, and neurodevelopmental factors.

Birthweight and risk markers for type 2 diabetes and cardiovascular disease in childhood: the Child Heart and Health Study in England (CHASE)

AIMS/HYPOTHESIS

Lower birthweight (a marker of fetal undernutrition) is associated with higher risks of type 2 diabetes and cardiovascular disease (CVD) and could explain ethnic differences in these diseases. We examined associations between birthweight and risk markers for diabetes and CVD in UK-resident white European, South Asian and black African-Caribbean children.

METHODS

In a cross-sectional study of risk markers for diabetes and CVD in 9- to 10-year-old children of different ethnic origins, birthweight was obtained from health records and/or parental recall. Associations between birthweight and risk markers were estimated using multilevel linear regression to account for clustering in children from the same school.

RESULTS

Key data were available for 3,744 (66%) singleton study participants. In analyses adjusted for age, sex and ethnicity, birthweight was inversely associated with serum urate and positively associated with systolic BP. After additional height adjustment, lower birthweight (per 100 g) was associated with higher serum urate (0.52%; 95% CI 0.38, 0.66), fasting serum insulin (0.41%; 95% CI 0.08, 0.74), HbA1c (0.04%; 95% CI 0.00, 0.08), plasma glucose (0.06%; 95% CI 0.02, 0.10) and serum triacylglycerol (0.30%; 95% CI 0.09, 0.51) but not with BP or blood cholesterol. Birthweight was lower among children of South Asian (231 g lower; 95% CI 183, 280) and black African-Caribbean origin (81 g lower; 95% CI 30, 132). However, adjustment for birthweight had no effect on ethnic differences in risk markers.

CONCLUSIONS/INTERPRETATION

Birthweight was inversely associated with urate and with insulin and glycaemia after adjustment for current height. Lower birthweight does not appear to explain emerging ethnic difference in risk markers for diabetes.

Birth data accessibility via primary care health records to classify health status in a multi-ethnic population of children: an observational study

Background:

Access to reliable birth data (birthweight (BW) and gestational age (GA)) is essential for the identification of individuals who are at subsequent health risk.

Aims:

This study aimed to explore the feasibility of retrospectively collecting birth data for schoolchildren from parental questionnaires (PQ) and general practitioners (GPs) in primary care clinics, in inner city neighbourhoods with high density of ethnic minority and disadvantaged populations.

Methods:

Attempts were made to obtain birth data from parents and GPs for 2,171 London primary schoolchildren (34% White, 29% Black African origin, 25% South Asians, 12% Other) as part of a larger study of respiratory health.

Results:

Information on BW and/or GA were obtained from parents for 2,052 (95%) children. Almost all parents (2,045) gave consent to access their children’s health records held by GPs. On the basis of parental information, GPs of 1,785 children were successfully contacted, and GPs of 1,202 children responded. Birth data were retrieved for only 482 children (22% of 2,052). Missing birth data from GPs were associated with non-white ethnicity, non-UK born, English not the dominant language at home or socioeconomic disadvantage. Paired data were available in 376 children for BW and in 407 children for GA. No significant difference in BW or GA was observed between PQ and GP data, with <5% difference between sources regardless of normal or low birth weight, or term or preterm status.

Conclusions:

Parental recall of birth data for primary schoolchildren yields high quality and rapid return of data, and it should be considered as a viable alternative in which there is limited access to birth records. It provides the potential to include children with an increased risk of health problems within epidemiological studies.

Role of the kidney in the fetal programming of adult cardiovascular disease: an update

It is well established that an adverse in utero environment can impinge upon fetal development and place the offspring on a track leading to future cardiovascular disease. Significantly, this may occur in the absence of any outward manifestations at birth. In this brief review, we focus on potential renal mechanisms that lead to adaptations in glomerular and tubular function that initiate hypertension of developmental origin and examine potential therapeutic interventions. This report updates recent data in this field.

Evidence for low high-density lipoprotein cholesterol levels in Australian indigenous peoples: a systematic review

Background

Low plasma high-density lipoprotein cholesterol (HDL-C) levels are a strong, independent, but poorly understood risk factor for cardiovascular disease (CVD). Although this atherogenic lipid abnormality has been widely reported in Australia’s Indigenous peoples, Aboriginal and Torres Strait Islanders, the evidence has not come under systematic review. This review therefore examines published data for Indigenous Australians reporting 1) mean HDL-C levels for both sexes and 2) factors associated with low HDL-C.

Methods

PubMed, Medline and Informit ATSI Health databases were systematically searched between 1950 and 2012 for studies on Indigenous Australians reporting mean HDL-C levels in both sexes. Retrieved studies were evaluated by standard criteria. Low HDL-C was defined as: <1.0 mmol/L. Analyses of primary data associating measures of HDL-C with other CVD risk factors were also performed.

Results

Fifteen of 93 retrieved studies were identified for inclusion. These provided 58 mean HDL-C levels; 29 for each sex, most obtained in rural/regional (20%) or remote settings (60%) and including 51–1641 participants. For Australian Aborigines, mean HDL-C values ranged between 0.81-1.50 mmol/L in females and 0.76-1.60 mmol/L in males. Two of 15 studies reported HDL-C levels for Torres Strait Islander populations, mean HDL-C: 1.00 or 1.11 mmol/L for females and 1.01 or 1.13 mmol/L for males. Low HDL-C was observed only in rural/regional and remote settings - not in national or urban studies (n = 3) in either gender. Diabetes prevalence, mean/median waist-to-hip ratio and circulating C-reactive protein levels were negatively associated with HDL-C levels (all P < 0.05). Thirty-four per cent of studies reported lower mean HDL-C levels in females than in males.

Conclusions

Very low mean HDL-C levels are common in Australian Indigenous populations living in rural and remote communities. Inverse associations between HDL-C and central obesity, diabetes prevalence and inflammatory markers suggest a particularly adverse CVD risk factor profile. An absence of sex dichotomy in HDL-C levels warrants further investigation.

Diabetes in pregnancy among indigenous women in Australia, Canada, New Zealand and the United States

Recently proposed international guidelines for screening for gestational diabetes mellitus (GDM) recommend additional screening in early pregnancy for sub-populations at a high risk of type 2 diabetes mellitus (T2DM), such as indigenous women. However, there are criteria that should be met to ensure the benefits outweigh the risks of population-based screening. This review examines the published evidence for early screening for indigenous women as related to these criteria. Any publications were included that referred to diabetes in pregnancy among indigenous women in Australia, Canada, New Zealand and the United States (n = 145). The risk of bias was appraised. There is sufficient evidence describing the epidemiology of diabetes in pregnancy, demonstrating that it imposes a significant disease burden on indigenous women and their infants at birth and across the lifecourse (n = 120 studies). Women with pre-existing T2DM have a higher risk than women who develop GDM during pregnancy. However, there was insufficient evidence to address the remaining five criteria, including the following: understanding current screening practice and rates (n = 7); acceptability of GDM screening (n = 0); efficacy and cost of screening for GDM (n = 3); availability of effective treatment after diagnosis (n = 6); and effective systems for follow-up after pregnancy (n = 5). Given the impact of diabetes in pregnancy, particularly undiagnosed T2DM, GDM screening in early pregnancy offers potential benefits for indigenous women. However, researchers, policy makers and clinicians must work together with communities to develop effective strategies for implementation and minimizing the potential risks. Evidence of effective strategies for primary prevention, GDM treatment and follow-up after pregnancy are urgently needed.