Unravelling the fetal origins hypothesis: is there really an inverse association between birthweight and subsequent blood pressure?

The association of birth weight and current BMI on the risk of hypertension: the Tohoku medical megabank community-based cohort study

This study aimed to investigate the association of combination of birth weight and current body mass index (BMI) with the risk of hypertension in adulthood. This cross-sectional study used data from the Tohoku Medical Megabank Community-based Cohort Study conducted in Japan. A total of 10,688 subjects aged ≥20 years were eligible. We calculated the least square (LS) means of systolic blood pressure (SBP) and trend tests were performed to evaluate the linear relationships between birth weight categories and SBP. We also used a multivariate logistic regression analysis to assess the risk of hypertension associated with the combination of birth weight and current BMI. There was a statistically inverse association between birth weight and SBP in the 20-64 age group, but no significant association in the ≥65 age group. Low birth weight (LBW) with normal BMI group had a higher risk of hypertension than the normal or high birth weight groups with normal BMI. Furthermore, the group with LBW and BMI ≥25.0 kg/m2 was the highest risk for hypertension (adjusted odds ratio: 2.73; 95% CI, 2.04-3.65) compared to the reference group (birth weight 2500-3499 g and BMI 18.5-24.9 kg/m2). There was a significant association between LBW and subsequent risk of hypertension. In addition, participants with lower birth weights had a higher risk of hypertension than those with higher birth weights. However, even in participants with a lower birth weight, the risk of hypertension could be reduced when they maintained an optimal BMI.

Breastfeeding in infancy and cardiovascular disease in middle-aged and older adulthood: a prospective study of 0.36 million UK Biobank participants

BACKGROUND

Cardiovascular disease originates in early life. We aimed to investigate the association between breastfeeding in infancy and cardiovascular disease in adult life.

METHODS

We followed 364,240 participants from UK Biobank aged 40-73 years from 2006 - 2010 to 2021. Information on breastfeeding in infancy was self-reported by questionnaire. Cox proportional hazard regression models were used to estimate the hazard ratios (HR) and 95% confidence intervals (CI) for the association between breastfeeding and cardiovascular disease in middle-aged and older adulthood. The multivariable Cox models were used by adjusting for the age (used as the time scale), sex, ethnicity, assessment centre, birth weight, multiple birth status, maternal smoking during pregnancy, Townsend deprivation index, smoking status, alcohol drinker status, physical activity, and menopausal status for women. Binary and multinomial multivariable logistic regression models were used to explore the associations of breastfeeding in infancy with cardiovascular disease risk factors including obesity, body composition, metabolic and inflammatory disorders.

RESULTS

During a median of 12.6 years of follow-up, we documented 29,796 new cases of cardiovascular disease, including 24,797 coronary heart disease and 6229 stroke. The multivariable adjusted HRs for breastfed versus non-breastfed were 0.94 (95% CI: 0.91, 0.96) for cardiovascular disease, 0.94 (95% CI: 0.91, 0.96) for coronary heart disease, and 0.95 (95% CI: 0.89, 1.01) for stroke. Furthermore, the strength of observed association between breastfeeding and cardiovascular disease seems to decrease with age (P for interaction <0.001), and increase with polygenic risk for cardiovascular disease (P for interaction <0.001). Consistently, breastfeeding in infancy was associated with cardiovascular disease risk factors including lower body mass index 0.92 (95% CI: 0.89, 0.95), body fat percentage 0.85 (95% CI: 0.83, 0.87), android to gynoid fat ratio 0.89 (95% CI: 0.83, 0.96), visceral adipose tissue 0.92 (95% CI: 0.84, 1.01), as well as lower C-reactive protein level 0.95 (95% CI: 0.94, 0.97) and a lower risk of metabolic syndrome 0.89 (95% CI: 0.85, 0.92).

CONCLUSIONS

Breastfeeding in infancy was associated with a lower risk of cardiovascular disease in middle-aged and older adulthood. Promoting breastfeeding is vital not only for promoting child health, but also for halting the increasing trend of cardiovascular disease in adults.

Does the evidence support in utero influences on later health and disease? A systematic review of highly cited Barker studies on developmental origins

The developmental origins of health and disease hypothesis proposes that early exposure to adverse conditions during fetal development and early life have strong detrimental consequences on long-term health and susceptibility to chronic diseases. We conducted a systematic review to critically appraise Barker's highest cited publications using the risk-of-bias assessment tool (ROBINS-I) and investigate effects of overadjustment by later body weight. Our findings revealed that all included studies displayed high risks of bias, with particular concerns regarding confounding (8/8), selection of reported results (8/8), classification of exposure (7/8), selection of participants (5/8) and high rates of missing data (ranged from 15 to 87%). Later body weight was over-adjusted in most (6/8) of the studies. As all studies displayed high bias risk due to confounding, missing data and overadjustment, evidence is insufficient to support causal relationships between low birthweight and adult disease, warranting caution in clinical application. PROTOCOL REGISTRATION: PROSPERO CRD42023433179.

Associations between placental hydroxymethylation and birthweight

5-hydroxymethylcytosine (5hmC), formed through the ten-eleven translocation (TET) methylcytosine dioxygenase mediated oxidation of 5-methylcytosine (5mC) at cytosine-phosphate-guanine (CpG) dinucleotides, is believed to mainly serve as an intermediate in the DNA demethylation pathway, though recent evidence suggests that 5hmC may also play a functionally relevant role. We have conducted an epigenome-wide association study (EWAS) to assess the association between placenta 5hmC, obtained through parallel bisulfite and oxidative bisulfite modification of DNA and array-based assessment, and newborn birthweight in the Rhode Island Child Health Study (RICHS). We also assessed whether the removal of 5hmC signal impacts the observed results from traditional epigenome-wide studies that rely on BS modification-based (combined 5mC and 5hmC) assessment alone. We identified 5hmC at one CpG in the CUBN gene to be significantly associated with birthweight (FDR < 0.05) and demonstrate that expression of that gene was also associated with birthweight. Comparison of 5hmC+5mC and 5mC EWAS effect estimates reveal a strong correlation (r = 0.77, p < 0.0001). Our study suggests that traditional assessment of 5mC through bisulfite modification alone provides an accurate assessment of CpG-specific DNA methylation for EWAS studies but was unable to provide evidence of widespread associations between placental 5hmC and birthweight.

Expected and Desirable Preterm and Small Infant Growth Patterns

Adequate nutrition is necessary for achieving optimal growth and neurodevelopment. Growth is a natural and expected process that happens concomitantly with rapid advancements in neurodevelopment. Serial weight, length, and head circumference growth measures are essential for monitoring development, although identifying pathological deviations from normal growth can pose challenges. Appropriate growth assessments require considerations that a range of sizes for length, head circumference, and weight are expected and appropriate. Because of genetic differences and morbidities, there is a considerable overlap between the growth of healthy infants and those with growth alterations. Parents tend to be over-concerned about children who plot low on growth charts and often need reassurance. Thus, the use of terms such as "poor" growth or growth "failure" are discouraged when growth is approximately parallel to growth chart curves even if their size is smaller than specific percentiles. No specific percentile should be set as a growth goal; individual variability should be expected. An infant's size at birth is important information that goes beyond the common use of prognostic predictions of appropriate compared with small or large for gestational age. The lower the birthweight, the lower the nutrient stores and the more important the need for nutrition support. Compared to term infants, preterm infants at term-equivalent age have a higher percentage of body fat, but this diminishes over the next months. Current research findings support expert recommendations that preterm infants should grow, after early postnatal weight loss, similar to the fetus and then term-born infants, which translates to growth approximately parallel to growth chart curves. There is no need for a trade-off between optimum cognition and optimum future health. Each high-risk infant needs individualized nutrition and growth assessments. This review aims to examine infant growth expectations and messaging for parents of preterm and term-born infants within the broader causal framework.

Birth History and Cardiovascular Disease Risk Among Youth With Significant Obesity

Children born prematurely have greater lifetime risk for hypertension. We aimed to determine (1) the association between prematurity and cardiovascular disease (CVD) risk factors among 90 children with obesity and elevated blood pressure and (2) if dietary sodium intake modified these associations. Multivariable regression analysis explored for associations between prematurity (<37 weeks gestation; early gestational age) and low birth weight (<2.5 kg) with hypertension, left ventricular mass index (LVMI), and left ventricular hypertrophy (LVH). Effect modification by dietary sodium intake was also explored. Patients were predominately male (60%), black (78%), adolescents (13.3 years), and with substantial obesity (body mass index: 36.5 kg/m2). Early gestational age/low birth weight was not an independent predictor for hypertension, LVMI, or LVH. There was no effect modification by sodium load. Our results suggest the increased CVD risk conferred by prematurity is less significant at certain cardiometabolic profiles. Promoting heart-healthy lifestyles to prevent pediatric obesity remains of utmost importance to foster cardiovascular health.

Nutritional Approaches Targeting Gut Microbiota in Oxidative-Stress-Associated Metabolic Syndrome: Focus on Early Life Programming

Metabolic syndrome (MetS) denotes a constellation of risk factors associated with the development of cardiovascular disease, with its roots potentially traced back to early life. Given the pivotal role of oxidative stress and dysbiotic gut microbiota in MetS pathogenesis, comprehending their influence on MetS programming is crucial. Targeting these mechanisms during the early stages of life presents a promising avenue for preventing MetS later in life. This article begins by examining detrimental insults during early life that impact fetal programming, ultimately contributing to MetS in adulthood. Following that, we explore the role of oxidative stress and the dysregulation of gut microbiota in the initiation of MetS programming. The review also consolidates existing evidence on how gut-microbiota-targeted interventions can thwart oxidative-stress-associated MetS programming, encompassing approaches such as probiotics, prebiotics, postbiotics, and the modulation of bacterial metabolites. While animal studies demonstrate the favorable effects of gut-microbiota-targeted therapy in mitigating MetS programming, further clinical investigations are imperative to enhance our understanding of manipulating gut microbiota and oxidative stress for the prevention of MetS.

Hemodynamic evaluation of extremely low birth weight infants during the first 7 days of life

BACKGROUND AND AIM

We aimed to investigate the hemodynamic status of extremely low birth weight (ELBW) infants during the transitional period under intensive management.

METHODS

This retrospective cohort study analyzed left ventricular ejection fraction (LVEF), left ventricular end-systolic wall stress (ESWS), left ventricular internal dimension in diastole (LVIDd), and mean arterial pressure (MAP) of ELBW infants during their first week of life. Small for gestational age (SGA), histological chorioamnionitis (hCAM), severe intraventricular hemorrhage (IVH), and non-survival to discharge infants were compared to their counterparts.

RESULTS

Sixty-two infants (25.7 ± 2.1 weeks, 700.7 ± 165.4 g) were analyzed. MAP gradually increased. Median LVEF was 69.8 % on day 1, decreased to 62.7 % on day 2, then increased throughout the week. ESWS was lowest at birth, rose to 28.2 g/cm2 on day 2, and decreased on day 6. There were no significant changes in LVIDd. SGA infants had higher MAP throughout, higher LVEF on day 2 and 3, but lower LVEF on day 5 to 7. LVIDd was lower in hCAM group. Severe IVH group had a more significant drop in LVEF on day 2, higher ESWS, and a higher incidence of hemodynamic significant patent ductus arteriosus (hsPDA). Non-survival had lower LVIDd.

CONCLUSIONS

MAP increased gradually. Hemodynamic instability was observed in the first two days, with decreased LVEF and increased ESWS before stabilization. We observed an alteration in hemodynamic adaptation in SGA and hCAM infants. Severe IVH group experienced early hemodynamic instability and a higher incidence of hsPDA.

Diabetes incidence in Austria: The role of famines on diabetes and related NCDs

Undernutrition in early life associates with increased risk for type 2 diabetes in later life. Whether similar associations hold for other diseases remains unclear. We aim to quantify how perinatal exposure to famines relates to the risk of becoming incident with type 2 diabetes in later life. Using population-wide medical claims data for Austrians aged >50y, yearly diabetes incidence was measured in an epidemiological progression model. We find incidence rates that increase from 2013 to 2017 and observe two famine-related birth cohorts of 5,887 patients with incidence rate increases for diabetes of up to 78% for males and 59% for females compared to cohorts born two years earlier. These cohorts show increased risks for multiple other diagnoses as well. Public health efforts to decrease diabetes must not only focus on lifestyle factors but also emphasize the importance of reproductive health and adequate nutrition during pregnancy and early postnatal life.

Birth size, growth trajectory and later cardio-metabolic risk

There is increasing evidence of a strong association between intrauterine growth and subsequent development of chronic disease in adult life. Birth size and growth trajectory have been demonstrated to have an impact on cardio-metabolic health, both in childhood and adult life. Hence, careful observation of the children's growth pattern, starting from the intrauterine period and the first years of life, should be emphasized to detect the possible onset of cardio-metabolic sequelae. This allows to intervene on them as soon as they are detected, first of all through lifestyle interventions, whose efficacy seems to be higher when they are started early. Recent papers suggest that prematurity may constitute an independent risk factor for the development of cardiovascular disease and metabolic syndrome, regardless of birth weight. The purpose of the present review is to examine and summarize the available knowledge about the dynamic association between intrauterine and postnatal growth and cardio-metabolic risk, from childhood to adulthood.

The association of gestational age and birthweight with blood pressure, cardiac structure, and function in 4 years old: a prospective birth cohort study

BACKGROUND

Current evidence relating birthweight and gestational age to cardiovascular risk is conflicting. Whether these factors have independent or interactive impacts on cardiovascular parameters during early childhood remains unclear. The goal of this study was to explore whether there were any independent and interactive effects of gestational age and birthweight on blood pressure, left ventricle (LV) structure, and function in 4 years old.

METHODS

This study included 1194 children in the Shanghai Birth Cohort from 2013 to 2016. Information about the mothers and children was recorded at time of birth using a questionnaire. Follow-up measurements, including anthropometric, blood pressure, and echocardiography, were taken between 2018 and 2021, when the children were 4 years old. Multiple linear or logistic regressions and restricted cubic spline were used to explore the association of birthweight and gestational age with cardiovascular measurements.

RESULTS

Gestational age had a significant negative correlation with both systolic blood pressure [β =  - 0.41, 95% CI: (- 0.76, - 0.07)] and mean arterial pressure [β =  - 0.36, 95%CI: (- 0.66, - 0.07)]. The risk of prehypertension decreased with increased gestational age [OR = 0.54, 95% CI: (0.32, 0.93)]. The relationship between birthweight with blood pressure was U-shape (P for non-linear < 0.001). The wall thickness, volume, mass, and cardiac output of LV increased with birthweight, though the ejection fraction [β =  - 1.02, 95% CI: (- 1.76, - 0.27)] and shorten fraction [β = 0.72, 95% CI: (- 1.31, - 0.14)] decreased with birthweight. The risk of LV hypertrophy was not associated with birthweight [OR = 1.59, 95% CI: (0.68, 3.73)].

CONCLUSIONS

In this study, we found different associations of birthweight and gestational age with cardiovascular measurements in the offspring at 4 years old. Gestational age influenced blood pressure independent of birthweight. Heart size and function at 4 years old was influenced mostly by birthweight and not by gestational age.

Early origins of metabolic and overall health in young adults: An outcome-wide analysis in a general cohort population

INTRODUCTION

Long-term consequences of impaired fetal growth are well documented for cardiometabolic outcomes. We propose an outcome-wide analysis of the association between birth weight (BW) and long-term health in a large contemporary adult cohort.

METHODS

The study included 73,315 participants under 60 years with a reliable BW from the French nationwide Constances cohort. Low and high BW (LBW/HBW) were defined as BW<10th and >90th of sex-specific percentiles. Associations between BW and outcomes were analyzed with a sex-stratified modified Poisson regression adjusted for the participant's age, maternal health history, geographical origins, and parents' occupation.

RESULTS

Mean BW (10^th -90^th percentile) was 3390 g (2800-4000) for men and 3247g (2680-3820) for women. In men, LBW was associated with (RR [CI95]): fasting glucose impairment (1.33 [1.16;1.52]); hypertriglyceridemia (1.27 [1.17;1.37]); high blood pressure (HBP) (1.15 [1.07;1.24]); non-alcoholic fatty liver disease NAFLD (1.13 [1.02;1.24]); high LDL-cholesterol (1.12 [1.05;1.21]); anxiety (1.12 [1.01;1.24]) and depression (1.09 [1.00;1.18]). HBW was associated with obesity (1.21 [1.08;1.35]). In women, LBW was associated with fasting glucose impairment (1.31 [1.12;1.54]); HBP (1.27 [1.16;1.4]); hypertriglyceridemia (1.20 [1.05;1.36]); anxiety (1.10 [1.03;1.17]); and asthma (1.09 [1;1.19}). HBW was associated with obesity (1.24 [1.13;1.36]) and NAFLD (1.20 [1.06;1.37). LBW and HBW were associated with a lesser likelihood of tertiary education attainment in both sexes. Participants' education level was a significant partial mediator of the association between LBW and outcomes.

CONCLUSION

Extreme BW is associated with long-term health. It should be considered in the personalized prevention of cardiometabolic, respiratory, and mental health conditions in adulthood, especially in socio-economically disadvantaged populations.

Small for date preterm infants and risk of higher blood pressure in later life: A systematic review and meta-analysis

BACKGROUND

Historical reports suggest that infants born small for gestational age (SGA) are at increased risk for high blood pressure (BP) at older ages after adjustment for later age body size. Such adjustment may be inappropriate since adiposity is a known cause of cardiovascular and metabolic disease.

OBJECTIVES

To assess the association between SGA births and later BP among preterm births, considering potential background confounders and over-adjustment for later body size.

METHODS

A database search of studies up to October 2022 included MEDLINE, EMBASE and CINAHL. Studies were included if they reported BP (systolic [SBP] or diastolic [DBP]) (outcomes) for participants born preterm with SGA (exposure) or non-SGA births. All screening, extraction steps, and risk of bias (using the Risk of Bias In Non-randomised Studies of Interventions [ROBINS-I] tool) were conducted in duplicate by two reviewers. Data were pooled in meta-analysis using random-effects models. We explored potential sources of heterogeneity.

RESULTS

We found no meaningful difference in later BP between preterm infants with and without SGA status at birth. Meta-analysis of 25 studies showed that preterm SGA, compared to preterm non-SGA, was not associated with higher BP at age 2 and older with mean differences for SBP 0.01 mmHg (95% CI -0.10, 0.12, I²  = 59.8%, n = 20,462) and DBP 0.01 mm Hg (95% CI -0.10, 0.12), 22 studies, (I²  = 53.0%, n = 20,182). Adjustment for current weight did not alter the results, which could be due to the lack of differences in later weight status in most of the included studies. The included studies were rated to be at risk of bias due to potential residual confounding, with a low risk of bias in other domains.

CONCLUSIONS

Evidence indicates that preterm infants born SGA are not at increased risk of developing higher BP as children or as adults as compared to non-SGA preterm infants.

Antenatal Programming of Hypertension: Paradigms, Paradoxes, and How We Move Forward

PURPOSE OF REVIEW

Synthesize the clinical, epidemiological, and preclinical evidence for antenatal programming of hypertension and critically appraise paradigms and paradoxes to improve translation.

RECENT FINDINGS

Clinical and epidemiological studies persistently demonstrate that antenatal factors contribute to programmed hypertension under the developmental origins of health and disease framework, including lower birth weight, preterm birth, and fetal growth restriction. Preclinical mechanisms include preeclampsia, maternal diabetes, maternal undernutrition, and antenatal corticosteroid exposure. However, clinical and epidemiological studies to date have largely failed to adequately identify, discuss, and mitigate many sources and types of bias in part due to heterogeneous study designs and incomplete adherence to scientific rigor. These limitations have led to incomplete and biased paradigms as well as persistent paradoxes that have significantly limited translation into clinical and population health interventions. Improved understanding of these paradigms and paradoxes will allow us to substantially move the field forward.

Anthropometric indices, but not birth weight, are associated with high blood pressure risk among Malay adolescents in Kuala Lumpur

Background

With the high prevalence of hypertension, it is important to determine its predictors early. The aim of this study was to determine the association between blood pressure with anthropometric indices and birth weight among a population of Malay adolescents in Kuala Lumpur.

Design and methods

This cross-sectional study was carried out among 254 primary and secondary school adolescents aged 10 to 16 years. Anthropometric measurements and blood pressure were determined through standardized protocols, while participants' birth weight was obtained from birth certificate. Body mass index (BMI), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and a body shape index (ABSI) were calculated.

Results

Boys had significantly higher weight, height, WC, WHtR and systolic blood pressure (SBP) than girls (p < 0.05). SBP was moderately correlated with body weight (r = 0.60), WC (r = 0.55), BMI (r = 0.54), height (r = 0.47), WHtR (rs = 0.36) and WHR (r = 0.30). Moderate correlations were found between diastolic blood pressure (DBP) with BMI (r = 0.26), WC (r = 0.23) and body weight (r = 0.20). Participants with BMI > +1SD had higher odds of being prehypertensive or hypertensive (aOR 8.97; 95% CI 3.16, 25.48), followed by participants with WC ≥ 90th percentile (aOR 6.31; 95% CI 2.48, 16.01) and participants with WHtR > 0.5 (aOR 5.10; 95% CI 2.05, 12.69). Multiple linear regression showed BMI was positively associated with both SBP and DBP. No significant association was found between birth weight and BP.

Conclusion

BMI had the best predictive ability for SBP and DBP. These findings strongly emphasize the importance of primary prevention of hypertension in adolescents, especially among those with high BMI.

Cardiovascular Dysfunction in Intrauterine Growth Restriction

PURPOSE OF REVIEW

We highlight important new findings on cardiovascular dysfunction in intrauterine growth restriction.

RECENT FINDINGS

Intrauterine growth restriction (IUGR) is a multifactorial condition which negatively impacts neonatal growth during pregnancy and is associated with health problems during the lifespan. It affects 5-15% of all pregnancies in the USA and Europe with varying percentages in developing countries. Epidemiological studies have reported that IUGR is associated with the pathogenesis of hypertension, activation of the renin-angiotensin system (RAS), disruption in placental-mTORC and TGFβ signaling cascades, and endothelial dysfunction in IUGR fetuses, children, adolescents, and adults resulting in the development of cardiovascular diseases (CVD). Experimental studies are needed to investigate therapeutic measures to treat increased blood pressure (BP) and long-term CVD problems in people affected by IUGR. We outline the mechanisms mediating fetal programming of hypertension in developing CVD. We have reviewed findings from different experimental models focusing on recent studies that demonstrate CVD in IUGR.

Metabolic Syndrome Programming and Reprogramming: Mechanistic Aspects of Oxidative Stress

Metabolic syndrome (MetS) is a worldwide public health issue characterized by a set of risk factors for cardiovascular disease. MetS can originate in early life by developmental programming. Increasing evidence suggests that oxidative stress, which is characterized as an imbalance between reactive oxygen species (ROS), nitric oxide (NO), and antioxidant systems, plays a decisive role in MetS programming. Results from human and animal studies indicate that maternal-derived insults induce MetS later in life, accompanied by oxidative stress programming of various organ systems. On the contrary, perinatal use of antioxidants can offset oxidative stress and thereby prevent MetS traits in adult offspring. This review provides an overview of current knowledge about the core mechanisms behind MetS programming, with particular focus on the occurrence of oxidative-stress-related pathogenesis as well as the use of potential oxidative-stress-targeted interventions as a reprogramming strategy to avert MetS of developmental origins. Future clinical studies should provide important proof of concept for the effectiveness of these reprogramming interventions to prevent a MetS epidemic.

Low Birthweight as a Risk Factor for Non-communicable Diseases in Adults

According to studies undertaken over the past 40 years, low birthweight (LBW) is not only a significant predictor of perinatal death and morbidity, but also increases the risk of chronic non-communicable diseases (NCDs) in adulthood. The purpose of this paper is to summarize the research on LBW as a risk factor for NCDs in adults. The Barker hypothesis was based on the finding that adults with an LBW or an unhealthy intrauterine environment, as well as a rapid catch-up, die due to NCDs. Over the last few decades, terminology such as thrifty genes, fetal programming, developmental origins of health and disease (DOHaD), and epigenetic factors have been coined. The most common NCDs include cardiovascular disease, diabetes mellitus type 2 (DMT2), hypertension (HT), dyslipidemia, proteinuria, and chronic kidney disease (CKD). Studies in mothers who experienced famine and those that solely reported birth weight as a risk factor for mortality support the concept. Although the etiology of NCD is unknown, Barry Brenner explained the notion of a low glomerular number (nGlom) in LBW children, followed by the progression to hyperfiltration as the physiopathologic etiology of HT and CKD in adults based on Guyton's renal physiology work. Autopsies of several ethnic groups have revealed anatomopathologic evidence in fetuses and adult kidneys. Because of the renal reserve, demonstrating renal function in proportion to renal volume in vivo is more difficult in adults. The greatest impact of these theories can be seen in pediatrics and obstetrics practice.

Fetal Undernutrition Programming, Sympathetic Nerve Activity, and Arterial Hypertension Development

A wealth of evidence showed that low birth weight is associated with environmental disruption during gestation, triggering embryotic or fetal adaptations and increasing the susceptibility of progeny to non-communicable diseases, including metabolic and cardiovascular diseases, obesity, and arterial hypertension. In addition, dietary disturbance during pregnancy in animal models has highlighted mechanisms that involve the genesis of arterial hypertension, particularly severe maternal low-protein intake (LP). Functional studies demonstrated that maternal low-protein intake leads to the renal decrease of sodium excretion and the dysfunction of the renin-angiotensin-aldosterone system signaling of LP offspring. The antinatriuretic effect is accentuated by a reduced number of nephron units and glomerulosclerosis, which are critical in establishing arterial hypertension phenotype. Also, in this way, studies have shown that the overactivity of the central and peripheral sympathetic nervous system occurs due to reduced sensory (afferent) renal nerve activity. As a result of this reciprocal and abnormal renorenal reflex, there is an enhanced tubule sodium proximal sodium reabsorption, which, at least in part, contributes directly to arterial hypertension development in some of the programmed models. A recent study has observed that significant changes in adrenal medulla secretion could be involved in the pathophysiological process of increasing blood pressure. Thus, this review aims to compile studies that link the central and peripheral sympathetic system activity mechanisms on water and salt handle and blood pressure control in the maternal protein-restricted offspring. Besides, these pathophysiological mechanisms mainly may involve the modulation of neurokinins and catecholamines pathways.

Critical examination of relationships between early growth and childhood overweight in extremely preterm infants

OBJECTIVES

To identify the prevalence and risk factors for childhood overweight and obesity (OWO) at 3-year corrected age in children born <1500 g <29 weeks gestation.

STUDY DESIGN

A multicentre retrospective cohort study for preterm infants admitted to neonatal intensive care units between 2001 and 2014.

RESULTS

Data were available for 911 (89.4%) of the 1019 infants who met the inclusion criteria. Of them, 22 (2.4%) had OWO. There were no associations between OWO and being small for gestational age (RR = 1.3, 95% confidence interval (CI): 0.3-5.4) or weight <10th percentile at 36 weeks (RR = 1.1, 95% CI: 0.4-2.8). OWO was associated with low maternal education (RR = 7.4, 95% CI: 2.1-26), maternal diabetes (RR = 5.2, 95% CI: 1.9-15) and neonatal brain injury (RR = 4.9, 95% CI: 1.8-14). Adjusting for concurrent child weight at 3 years of age resulted in an overadjustment bias.

CONCLUSION

Small size at birth or at 36 weeks gestation in extremely preterm infants is not associated with increased risk of early childhood overgrowth or obesity.

CLINICAL TRIAL REGISTRATION

NCT03064022.

Birthweight predicts glomerular filtration rate in adult-life: population based cross sectional study

INTRODUCTION

Worldwide, there is a global progressive rise of chronic kidney disease. In parallel, children born after intra-uterine growth retardation are surviving to adult-life and beyond. This study describes the association of birthweight with and estimated glomerular filtration rate (eGFR).

METHODS

Australian Diabetes, Obesity and Lifestyle (AusDiab) study participants were asked to complete a birthweight questionnaire. The associations between birthweight and eGFR were determined.

RESULTS

A total of 4502 reported information related to their birthweight, with the other responders did not provide a value. The birthweight of the participants ranged from 0.4 to 7.0 kg with a mean-(SD) of 3.37 (0.7) kg. The mean (95%CI) birthweight was lower for females, 3.28 (0.6) kg, when compared to males, 3.5 (0.7) kg. Eight percent had a birthweight less than 2.5 kg. The eGFR was strongly and positively associated with birthweight, with people in the lowest sex-specific birthweight-quintiles having the lowest mean eGFR. This relationship persisted with adjustment for confounding factors. The OR(CI) for eGFR <10th-percentile (<61.4 ml/min for females and <73.4 for males) for people in the lowest vs. the higher birthweight-quintile was 2.19 (95%CI 1.14-4.2) for females and 2.37 (1.1-5.3) for males, after adjustment for other factors.

CONCLUSIONS

Birthweight had a positive relationship with eGFR. Possible explanations include an association of birthweight with nephron-endowment. From a global health perspective but more in developing countries and in populations in epidemiologic transition, where substantially lower birthweights coexist with recently improved infant and adult survivals, the overall impact of this phenomenon on the population health profile could be more substantial.

Maternal body mass index, offspring body mass index, and blood pressure at 18 years: a causal mediation analysis

OBJECTIVE

Understanding the natural history of hypertension is key to identifying prevention strategies. Previous work suggests that in utero exposures and offspring anthropometrics may play a role. This study examined the relationship between maternal pre-pregnancy body mass index (BMI) and the mediating role of childhood and adolescent BMI on offspring blood pressure at 18 years.

METHODS

We performed multivariable regression and causal mediation analyses within 3217 mother - offspring pairs from the Avon Longitudinal Study of Parents and Children prospective birth cohort. The main exposure was maternal pre-pregnancy BMI, and the outcome was offspring blood pressure at 18 years of age categorized as normal or elevated. Latent trajectory analysis was used to quantify the mediator, offspring BMI trajectories, derived from multiple measurements throughout childhood and adolescence. Mediation analyses were repeated using current offspring BMI at 18 years as a continuous variable.

RESULTS

Multivariable logistic regression revealed that for every 1 unit increase in maternal BMI, the risk of elevated blood pressure at 18 years of age increased by 5% (aOR: 1.05, 95% CI: 1.03-1.07; p < 0.001). The strength of this association was reduced after adjusting for offspring BMI trajectory (aOR: 1.03, 95% CI: 1.00-1.05; p = 0.017) and eliminated after adjusting for offspring BMI at 18 years (aOR: 1.00; 95% CI: 0.98-1.03; p = 0.70). Causal mediation analysis confirmed offspring BMI at 18 years as a mediator, where BMI trajectory accounted for 46% of the total effect of maternal BMI on elevated offspring blood pressure and current BMI account for nearly the entire effect.

CONCLUSIONS

Maternal pre-pregnancy BMI is associated with an increased risk of elevated blood pressure in offspring at 18 years of age although it appears to be entirely mediated by offspring BMI.

Birth Weight Predicts Anthropometric and Body Composition Assessment Results in Adults: A Population-Based Cross-Sectional Study

BACKGROUND

A poor intrauterine environment is associated with increased risks of hypertension, chronic kidney disease, and/or diabetes. This study evaluated relationships between birth weight and body habitus in a representative sample of the general population.

METHODS

Adult participants were asked to complete a birth weight questionnaire. Associations between various current anthropometric and body composition measurements and birth weight were investigated.

RESULTS

Of 7,157 respondents, 4,502 reported their birth weight, which ranged from 0.4 to 7.0 kg with a mean and standard deviation of 3.37±0.7 kg; of these, 384 had low birth weights (LBWs; <2.5 kg). In females, lower birth weights were associated with lower height, weight, lean body mass (LBM), total body water (TBW), fat mass (FM), fat%, and fat-free mass (FFM) than those of higher older birth weights (quintiles); however, waist circumference (WC), and hip circumference (HC) were similar across quintiles. In males, LBW was similarly associated with lower height, weight, LBM, TBW, FM, fat%, and FFM, and also with lower WC and HC. The obesity markers such as WC, WHR, and body mass index (BMI) were 47%, 61%, and 45% greater, respectively, in LBW females compared to normal birth weight females, while these associations showed non-significant trend in males with LBW.

CONCLUSION

In adult male and female respondents, LBW was associated with lower body habitus: central obesity and body fatness (BMI, FM, fat%, FFM, FM/FFM, and FM/FFM²) were more pronounced in females than males, even after taking into account current physical activity and socioeconomic status. These findings indicate LBW may contribute to high blood pressure, dysglycemia and metabolic-abnormalities in adults.

Short- and Long-Term Implications of Small for Gestational Age

Fetal growth restriction (FGR) describes a fetus' inability to attain adequate weight gain based on genetic potential and gestational age and is the second most common cause of perinatal morbidity and mortality after prematurity. Infants who have suffered fetal growth restriction are at the greatest risks for short- and long-term complications. This article specifically details the neurologic and cardiometabolic sequalae associated with fetal growth restriction, as well as the purported mechanisms that underlie their pathogenesis. We end with a brief discussion about further work that is needed to gain a more complete understanding of fetal growth restriction.

Are small-for-gestational-age preterm infants at increased risk of overweight? Statistical pitfalls in overadjusting for body size measures

OBJECTIVE

The objective of this study is to analyze the effect of adjusting for body measures on the association between small for gestational age (SGA) and overweight at 3 years.

STUDY DESIGN

Data were obtained from the Preterm Infant Multicenter Growth Study (n = 1089). Logistic regression was used, to adjust for confounders with additional adjustments separately for weight and height at 21 months. Marginal structural models (MSMs) estimated the direct effect of SGA on overweight.

RESULTS

The crude and adjusted for confounders models yielded null associations between SGA and overweight. Adjusting for height yielded a positive association (odds ratio (OR): 2.31, 95% CI: 0.52-10.26) and adjusting for weight provided a significantly positive association (OR: 6.60, 95% CI: 1.10-37.14). The MSMs, with height and weight held constant, provided no evidence for a direct effect of SGA on overweight (OR: 0.83, 95% CI: 0.14-5.01, OR: 0.71, 95% CI: 0.18-2.81, respectively).

CONCLUSION

Adjusting for body measures can change the association between SGA and overweight, providing spurious estimates.

Birth Size as a Determinant of Cardiometabolic Risk Factors in Children

The association between birth size and cardiometabolic disease risk may be U-shaped. Being born small for gestational age (SGA) has a definitive association with later cardiovascular risk, but the impact of being born large for gestational age (LGA) on cardiometabolic health is more controversial. In addition to birth size, early postnatal growth pattern and later weight gain affect cardiometabolic risk in adulthood. Most SGA-born children have catch-up and LGA-born children have catch-down growth during the first years of life. The extent of this early compensatory growth may contribute to the adverse health outcomes. Both SGA- and LGA-born children are at an increased risk for overweight and obesity. This may have a long-term impact on cardiometabolic health as overweight tends to track to adulthood. Other cardiometabolic risk factors, including alterations in glucose metabolism, dyslipidemia, hypertension, and low-grade inflammation are associated with birth weight. Many of these risk factors are related to overweight or adverse fat distribution. Since later cardiometabolic risk is often mediated by early growth pattern and later overweight in SGA and LGA children, it is important to focus on staying normal weight throughout life. Hence, effective interventions to reduce cardiometabolic risk in LGA and SGA children should be developed.

Birth Weight and Adult Obesity Index in Relation to the Risk of Hypertension: A Prospective Cohort Study in the UK Biobank

Objectives: To investigate the association between birth weight and the risk of hypertension, and to examine the interaction between birth weight and the adult obesity index.

Methods: We included 199,893 participants who had birth weight data and no history of hypertension at baseline (2006–2010) from the UK Biobank. A multivariate cubic regression spline was used to visually explore the dose-response relationship. Multivariate Cox proportional hazard regression models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).

Results: We observed a nonlinear inverse association between birth weight and hypertension. The risk for hypertension decreased as birth weight increased up to approximately 3.80 kg. Compared with the participants with the fourth quintile of birth weight (3.43–3.80 kg), those with the first quartile of birth weight (<2.88 kg) were associated with a 25% higher risk of hypertension [HR 1.25; 95% CI (1.18–1.32)]. In addition, the participants with birth weight <2.88 kg and body mass index ≥30 kg/m² had the highest risk [HR 3.54; 95% CI (3.16–3.97); p for interaction <0.0001], as compared with those with birth weight between 3.43–3.80 kg and body mass index between 18.5–25.0 kg/m². These associations were largely consistent in the stratified and sensitivity analyses.

Conclusion: Our findings indicate that lower birth weight is nonlinearly correlated with higher risk of hypertension, and birth weight between 3.43–3.80 kg might represent an intervention threshold. Moreover, lower birth weight may interact with adult obesity to significantly increase hypertension risk.

Effects of prenatal exposure factors on birth outcomes through mediation of favorable fetal growth conditions using structural equation modeling

Background

Birth weight, birth length, and gestational age are major indicators of newborn health. Several prenatal exposure factors influence the fetal environment. The aim of the study was to investigate the effect of prenatal exposure factors, including socio-demographic, behavioural, dietary, physical activity, clinical and environmental on birth outcomes through the mediation of Favourable Fetal Growth Conditions (FFGC).

Methods

Data was obtained from six hundred and fifty-six Mother and Child in the Environment birth cohort study in Durban, South Africa from 2013 to 2017. We adopted structural equation models which evaluate the direct and indirect effects by allowing multiple simultaneous equations to incorporate confounding and mediation.

Results

A significant direct and indirect effect of FFGC on newborn weight, length, and gestational age was seen. Gestational weight gain and maternal body mass index in the first trimester exerted a mediation effect between maternal behavioural risk factors and FFGC. Similarly, the level of physical activity during pregnancy was associated with decreased gestational weight gain. The effects of maternal characteristics on newborn weight, length, and gestational age were largely indirect, operating through FFGC as a latent variable.

Conclusions

Gestational weight gain and maternal pre-gestational BMI were observed to mediate the association between prenatal behavioural risk factors and favourable fetal growth conditions.

Trial registration

Retrospectively registered from 01 March 2013.

Developmental programming of cardiovascular function: a translational perspective

The developmental origins of health and disease (DOHaD) is a concept linking pre- and early postnatal exposures to environmental influences with long-term health outcomes and susceptibility to disease. It has provided a new perspective on the etiology and evolution of chronic disease risk, and as such is a classic example of a paradigm shift. What first emerged as the 'fetal origins of disease', the evolution of the DOHaD conceptual framework is a storied one in which preclinical studies played an important role. With its potential clinical applications of DOHaD, there is increasing desire to leverage this growing body of preclinical work to improve health outcomes in populations all over the world. In this review, we provide a perspective on the values and limitations of preclinical research, and the challenges that impede its translation. The review focuses largely on the developmental programming of cardiovascular function and begins with a brief discussion on the emergence of the 'Barker hypothesis', and its subsequent evolution into the more-encompassing DOHaD framework. We then discuss some fundamental pathophysiological processes by which developmental programming may occur, and attempt to define these as 'instigator' and 'effector' mechanisms, according to their role in early adversity. We conclude with a brief discussion of some notable challenges that hinder the translation of this preclinical work.

Age-related suppression effect of current body weight on the association between birthweight and blood pressure: The Bogalusa heart study

BACKGROUND

It has been controversial whether to adjust for current body weight while examining the relationship between birthweight and blood pressure (BP).

OBJECTIVE

The present study aims to partition the total effect of birthweight on BP into its direct effect and indirect effect through current body mass index (BMI).

METHODS

The study cohort consisted of 6251 participants who had birthweight information with 13 443 observations on BMI and BP in pre-adolescence (4-11 years), adolescence (12-19 years), young adulthood (20-30 years) and mid-adulthood (31-58 years). General third-variable models were used to distinguish the mediation and suppression effects of current BMI on the birthweight-BP association at different ages.

RESULTS

The total effect of birthweight on systolic BP measured as standardized regression coefficient (β) without current BMI included in the model was 0.003 (P = .810) in pre-adolescents, -0.032 (P = .029) in adolescents, -0.066 (P = .002) in young adults and -0.051 (P = .023) in midlife adults. With additional adjustment for BMI, the direct effect of birthweight on systolic BP was strengthened to β = -0.066 (P = .013), β = -0.058 (P = .014), β = -0.094 (P = .020), β = -0.066 (P = .023); the suppression effects of BMI were calculated at 0.070, 0.027, 0.028 and 0.015 in the respective age groups. The decreasing trend of suppression effects with increasing age mimicked the trends of birthweight-BMI and BMI-BP correlations.

CONCLUSIONS

Current body weight has a suppression effect, not a mediation effect, on the birthweight-BP association, with pre-adolescents having the greatest suppression effect. The suppression effect is predominantly determined by birthweight-BMI and BMI-BP correlations.

Associations of maternal metabolic profile with placental and fetal cerebral and cardiac hemodynamics

OBJECTIVE

Maternal obesity and metabolic health affect pregnancy outcomes. We examined whether maternal metabolic profiles are associated with placental and fetal hemodynamics.

STUDY DESIGN

In a population-based prospective cohort study among 1175 women we examined the associations of an adverse maternal metabolic profile in early pregnancy with placental, fetal cerebral and cardiac hemodynamic development. We obtained maternal pre-pregnancy BMI by questionnaire and measured blood pressure, cholesterol, triglycerides and glucose concentrations at a median gestational age of 12.6 (95 % range 9.6-17.1) weeks. An adverse maternal metabolic profile was defined as ≥4 risk factors. Placental and fetal hemodynamics were measured by pulsed-wave-Doppler at a median gestational age of 30.3 (95 % range 28.8-32.3) weeks.

RESULTS

An adverse maternal metabolic profile was associated with a 0.29 Z-score higher (95 %CI 0.08-0.50) fetal cerebral middle artery pulsatility index (PI), but not with placental or fetal cardiac hemodynamic patterns. When the individual components of an adverse maternal metabolic profile were assessed, we observed that higher maternal total cholesterol and triglyceride concentrations were associated with a higher cerebral middle artery PI (Z-score, 0.09 (95 %CI 0.02-0.15), 0.09 (95 %CI 0.03-0.15) per Z-score increase). Higher total and HDL maternal cholesterol concentrations were also associated with a higher aorta ascendens peak systolic velocity (PSV) Z-score, 0.08 (95 %CI 0.01-0.14)), and a larger left cardiac output (Z-score, 0.08 (95 %CI 0.00-0.15), respectively).

CONCLUSION

An adverse maternal metabolic profile, especially higher cholesterol and triglycerides concentrations, are associated with increased fetal cerebral vascular resistance and larger fetal aorta ascendens diameter, PSV and left cardiac output, but not with placental vascular resistance indices. Further studies are needed to identify long-term consequences of the observed associations.

Birth weight is inversely correlated with blood pressure: population-based study

BACKGROUND AND METHOD

The current representative national cross-sectional study examines the association of birth weight and blood pressure (BP) among the adult Australian population.Questions about birth weight were added to the second round of AusDiab study. Hypertension was defined based on WHO (≥140/90), and NCEP-ATPIII (≥130/85). Both definitions were examined against the continuous birth weight and dichotomous variable of low birth weight (LBW); less than 2.5 kg, adjusting for age, BMI, physical activity, smoking, alcohol intake and socioeconomic factors.

RESULTS

A total of 4502 respondents reported their birth weights with a mean (SD) of 3.37 (0.7) kg. Females with LBW had significantly higher mean SBP and DBP than those with normal birth weight. This relationship persisted with adjustments for various confounding factors. Males with LBW showed a trend towards a higher SBP and DBP, though NS, than normal birth weight more than 2.5 kg. LBW individuals, less than 2.5 kg were at higher risk for having high SBP hypertension at least 140/90 mmHg and at least 130/85 mmHg compared with those with normal birth weight. Among females, for each kilogramme of birth weight, there was a predicted decrease of 1.59 (0.7, 2.5) mmHg in SBP, P = 0.001 and 0.85 (0.2, 1.5) mmHg in DBP, P = 0.001; after adjustments for age, body size, physical activity, smoking status, alcohol intake and socioeconomic factors. Among males, for each kilogramme of birth weight, there was a decrease of 1.74 (0.7, 2.8) mmHg in SBP, P = 0.002 and 1.06 (0.3, 1.9) mmHg in DBP, P = 0.008 after adjustments for all confounding factor.

CONCLUSION

This study has examined the association of birth weight and BP in a representative adult population. LBW was significantly associated with the risk of developing high BP.

Birthweight predicts adult cardiovascular disorders: Population based cross sectional survey

BACKGROUND

Cardiovascular disease (CVD) is the primary cause of death in the developed-countries and mostly in the poorer areas of the country, and in lower income-groups.

HYPOTHESIS

Birthweight predicts adult development of angina, coronary heart disease, stroke, and combination of all CVD.

METHODS

The AusDiab is a cross-sectional study of Australians aged 25 years or over. Data on age, sex, previous-CVD, smoking-status, alcohol-intake, time-spent on watching television and physical-activity, total house-income, dwelling-type and education-level were collected by interviewer- administered-questionnaires.

RESULTS

Four thousand five hundred and two had birthweights (mean (SD) of 3.4(0.7) kg). Females in the lowest birthweight-quintile were at least 1.23, 1.48, 1.65, and 1.23 times more likely to have angina, CAD, stroke, and CVS compared to the referent group ≥3.72 kg with P = .123, .09, .099, and 0.176, respectively. Similarly, males in the lowest-birthweight-quintile were 1.23, 1.30, 1.39, and 1.26 times more likely to have angina, CAD, stroke, and CVS compared to the referent-group ≥4.05 kg with P = .231, .087, .102, and .123, respectively. Females with low birth weight (LBW) were at least 1.39, 1.40, 2.30, and 1.47 times more likely to have angina, CAD, stroke and CVS compared to those ≥2.5 kg with P = .06, .19, .03, and .13, respectively. Similarly, males with LBW were 1.76, 1.48, 3.34, and 1.70 times more likely to have angina, CAD, stroke, and CVS compared to those ≥2.5 kg with P = .14, .13, .03, and .08, respectively.

CONCLUSION

there was a negative relationship between birth weight and angina, CAD, stroke, and the overall CVS. It would be prudent, to adopt policies of intensified whole of life surveillance of lower-birthweight people, anticipating this risk.

Pre-pregnancy body mass index in mothers, birth weight and the risk of type I diabetes in their offspring: A dose-response meta-analysis of cohort studies

BACKGROUND

The incidence of type I diabetes among children has increased significantly and the relationship between maternal pre-pregnancy Body Mass Index (BMI), Birth weight and risk of Type 1 diabetes in children (T1DMC) is controversial.

OBJECTIVE

This dose-response meta-analysis was performed to investigate the association between maternal Pre-Pregnancy Body-Mass Index, Birth Weight and the Risk of Childhood Type I Diabetes.

SEARCH STRATEGY

A comprehensive systematic search was conducted in MEDLINE/PubMed, SCOPUS, Cochrane, and Web of Science databases from inception to April 2019. Key search terms included "body mass index" OR "Birth weight" AND "Type 1 diabetes".

SELECTION CRITERIA

Peer-reviewed studies that reporting association between BMI or birth weight and type I diabetes in a retrospective or prospective study by appropriate estimates such as the hazard ratio (HR), risk ratio (RR), or odds ratio (OR) and the corresponding 95 % confidence intervals (CI).

DATA COLLECTION AND ANALYSIS

MOOSE guidelines were followed. Data were extracted by 2 researchers, independently. Combined hazard ratios (HRs) was evaluated by DerSimonian and Laird Random-effects model.

RESULTS

Two studies continuing four arms with 1,209,122 participants were eligible for pre-pregnancy BMI section meta-analysis and six studies were eligible for inclusion, providing 10,340,036 participants for birth weight section meta-analysis. Pooled results demonstrated a significant association between obesity and risk of T1DMC (HR: 1.30, 95 % CI: 1.16-1.46, I2 = 7%). The combined HR (95 % CI) showed lower risk of T1DMC in low birth weight infants (HR: 0.78, 95 % CI: 0.69-0.88, I2 = 0%) and higher risk of T1DMC in the high birth weight infants versus the normal category of birth weight (HR: 1.08, 95 % CI: 1.00-1.17, I2 = 31 %). There was a significant non-linear association between birth weight and risk of T1DMC in children (Coef =-0.00032, p = 0.001).

CONCLUSIONS AND RELEVANCE

This systematic review and meta-analysis identified high maternal BMI and High birth weight (HBW) increase risk of childhood T1DMC.

Developmental origins of cardiometabolic health outcomes in twins: A systematic review and meta-analysis

BACKGROUND AND AIMS

Studies of twins can reduce confounding and provide additional evidence about the causes of disease, due to within-pair matching for measured and unmeasured factors. Although findings from twin studies are typically applicable to the general population, few studies have taken full advantage of the twin design to explore the developmental origins of cardiometabolic health outcomes. We aimed to systematically review the evidence from twin studies and generate pooled estimates for the effects of early-life risk factors on later-life cardiometabolic health.

METHODS AND RESULTS

An initial search was conducted in March 2018, with 55 studies of twins included in the review. Risk of bias was assessed using the Newcastle-Ottawa Scale, and eligible studies were included in a meta-analysis, where pooled estimates were calculated. Twenty-six studies analysed twins as individuals, and found that higher birthweight was associated with lower SBP (β = -2.02 mmHg, 95%CI: -3.07, -0.97), higher BMI (β = 0.52 kg/m², 95%CI: 0.20, 0.84) and lower total cholesterol (β = -0.07 mmol/L, 95%CI: -0.11, -0.04). However, no associations were reported in studies which adjusted for gestational age. Few of the included studies separated their analyses into within-pair and between-pair associations.

CONCLUSIONS

Early-life risk factors were associated with cardiometabolic health outcomes in twin studies. However, many estimates from studies in this review were likely to have been confounded by gestational age, and few fully exploited the twin design to assess the developmental origins of cardiometabolic health outcomes.

Appropriate-for-gestational-age infants who exhibit reduced antenatal growth velocity display postnatal catch-up growth

Background

Postnatally, small-for-gestational-age (SGA; birthweight <10th centile) infants who are growth restricted due to uteroplacental insufficiency (UPI) demonstrate ‘catch-up growth’ to meet their genetically-predetermined size. Infants who demonstrate slowing growth during pregnancy are those that cross estimated fetal weight centiles at serial ultrasound examinations. These infants that slow in growth but are born appropriate-for-gestational-age (AGA; ≥10th centile), exhibit antenatal, intrapartum and postnatal indicators of UPI. Here, we examine if and when these infants (labelled as AGA-FGR) also demonstrate catch-up growth like SGA infants, when compared with AGA infants with normal antenatal growth velocity (AGA-NG).

Methods

We followed-up the infants of women who had previously undergone ultrasound assessment of fetal size at 28- and 36-weeks’ gestation, enabling calculation of antenatal growth velocity. To assess postnatal growth, we asked parents to send their infant’s growth measurements, up to two years post-birth, which are routinely collected through the state-wide Maternal-Child Health service. Infants with medical conditions affecting postnatal growth were excluded from the analysis. From the measurements obtained we calculated age-adjusted z-scores for postnatal weight, length and body mass index (BMI; weight(kg)/height(m²)) at birth and 4, 8, 12, 18 and 24 months. We used linear spline regression modelling to predict mean weight, length and BMI z-scores at intervals post birth. Predicted mean age-adjusted z-scores were then compared between three groups; SGA, AGA with low antenatal growth (AGA-FGR; loss of >20 customised estimated fetal weight centiles), and AGA-NG to determine if catch-up growth occurred. In addition, we compared the rates of catch-up growth (defined as an increase in weight age-adjusted z-score of ≥0.67 over 1 year) between the groups with Fisher’s exact tests.

Results

Of 158 (46%) infant growth records received, 146 were AGA, with low antenatal growth velocity occurring in 34/146 (23.2%). Rates of gestational diabetes and SGA birthweight were higher in those lost to follow-up. Compared to AGA-NG infants, AGA-FGR infants had significantly lower predicted mean weight (p<0.001), length (p = 0.04) and BMI (p = 0.001) z-scores at birth. These significant differences were no longer evident at 4 months, suggesting that catch-up growth had occurred. As expected, the catch-up growth that occurred among the AGA-FGR was not as great in magnitude as that demonstrated by the SGA. When assessed categorically, there was no significant difference between the rate of catch-up growth among the AGA-FGR and the SGA. Catch-up growth was significantly more frequent among both the AGA-FGR and the SGA groups compared to the AGA-NG.

Conclusions

AGA infants that have exhibited reduced antenatal fetal growth velocity also exhibit significant catch-up growth in the first 12 months of life. This finding represents further evidence that AGA fetuses that slow in growth during pregnancy do so due to UPI.

Association of High Birth Weight With Incident Heart Failure in the ARIC Study

Background

Traditional risk factors for heart failure––coronary heart disease, hypertension, diabetes mellitus, obesity, and smoking––only account for about 50% of cases. Thus, the identification of novel risk factors is of significant public health importance. As high birth weight infants are at increased risk for obesity and diabetes mellitus later in life, which are both risk factors for the development of heart failure, we sought to assess the association of high birth weight with incident heart failure in the ARIC (Atherosclerosis Risk in Communities) study.

Methods and Results

The ARIC study is a biracial prospective community‐based investigation of 15 792 individuals aged 45 to 64 years at baseline. Study participants who were born premature or born a twin were excluded from this analysis, resulting in 9820 participants who provided either their birth weight category (low, medium, high) or exact birth weight. After adjusting for differences in demographics, risk factors, and comorbidities, compared with medium birth weight, those with high birth weight had a significantly increased risk of incident heart failure (hazard ratio, 1.27; 95% CI, 1.05–1.54 [P=0.014]). The hazard for all‐cause mortality for high birth weight compared with medium birth weight was 1.16 (95% CI, 0.99–1.34; P=0.06). There was no association of high birth weight with myocardial infarction (hazard ratio, 1.06; 95% CI, 0.84–1.34 [P=0.6]).

Conclusions

High birth weight was associated with a significantly increased hazard of incident heart failure independent of traditional risk factors and a trend toward an increased hazard of death. A history of high birth weight should be ascertained in young adults for primordial prevention of heart failure and in older adults for primary prevention.

The COVID-19 Pandemic: Does Our Early Life Environment, Life Trajectory and Socioeconomic Status Determine Disease Susceptibility and Severity?

A poor socioeconomic environment and social adversity are fundamental determinants of human life span, well-being and health. Previous influenza pandemics showed that socioeconomic factors may determine both disease detection rates and overall outcomes, and preliminary data from the ongoing coronavirus disease (COVID-19) pandemic suggests that this is still true. Over the past years it has become clear that early-life adversity (ELA) plays a critical role biasing the immune system towards a pro-inflammatory and senescent phenotype many years later. Cytotoxic T-lymphocytes (CTL) appear to be particularly sensitive to the early life social environment. As we understand more about the immune response to SARS-CoV-2 it appears that a functional CTL (CD8+) response is required to clear the infection and COVID-19 severity is increased as the CD8+ response becomes somehow diminished or exhausted. This raises the hypothesis that the ELA-induced pro-inflammatory and senescent phenotype may play a role in determining the clinical course of COVID-19, and the convergence of ELA-induced senescence and COVID-19 induced exhaustion represents the worst-case scenario with the least effective T-cell response. If the correct data is collected, it may be possible to separate the early life elements that have made people particularly vulnerable to COVID-19 many years later. This will, naturally, then help us identify those that are most at risk from developing the severest forms of COVID-19. In order to do this, we need to recognize socioeconomic and early-life factors as genuine medically and clinically relevant data that urgently need to be collected. Finally, many biological samples have been collected in the ongoing studies. The mechanisms linking the early life environment with a defined later-life phenotype are starting to be elucidated, and perhaps hold the key to understanding inequalities and differences in the severity of COVID-19.

Birthweight and Lipids in Adult Life: Population-Based Cross Sectional Study

The purpose of this study was to examine the association of birthweight with lipid profile in the general adult population. Participants in the second-wave of a nationally representative cross sectional AusDiab-study were asked to complete a birthweight questionnaire. Fasting total cholesterol (TC), LDL-C, HDL-C, and triacylglycerol levels were modeled against birthweight. Four thousand five hundred and two people reported their birthweights, mean (SD) of 3.4(0.7) kg. Females with low birthweight-LBW had higher levels of TC, LDL-C, and triacylglycerols, but no difference in HDL-C, than those with normal-birthweight-NBW;≥2.5 kg. People with LBW showed a trend toward increased risk for high TC (≥5.5 mmol/L) compared to NBW. Among females with LBW, the risk for high LDL-C (≥3.5 mmol/L) was increased compared to those of NBW. The risk for low HDL-C (<0.9 mmol/L) was increased among males with LBW compared to those with NBW. Examination of the relationship on the continuum showed no differences except for high triacylglycerol levels among females with the lowest birthweight quintile compared to the higher birthweight quintile. However, the risk for various abnormalities by birthweight quintiles was similar to that when we used the traditional definition of LBW vs. NBW. Females and males with low birthweight differ in their risk for lipids abnormalities. Females had higher risk for high LDL-C, whereas males had high risk for low HDL-C (<0.9 mmol/L). In addition, females with low birthweight had the highest triacylglycerol levels. High LDL-C, low HDL-C, and high triacylglycerols are well-recognized risk factors for cardiovascular disease.

Mendelian randomization analysis does not support causal associations of birth weight with hypertension risk and blood pressure in adulthood

Epidemiology studies suggested that low birthweight was associated with a higher risk of hypertension in later life. However, little is known about the causality of such associations. In our study, we evaluated the causal association of low birthweight with adulthood hypertension following a standard analytic protocol using the study-level data of 183,433 participants from 60 studies (CHARGE-BIG consortium), as well as that with blood pressure using publicly available summary-level genome-wide association data from EGG consortium of 153,781 participants, ICBP consortium and UK Biobank cohort together of 757,601 participants. We used seven SNPs as the instrumental variable in the study-level analysis and 47 SNPs in the summary-level analysis. In the study-level analyses, decreased birthweight was associated with a higher risk of hypertension in adults (the odds ratio per 1 standard deviation (SD) lower birthweight, 1.22; 95% CI 1.16 to 1.28), while no association was found between genetically instrumented birthweight and hypertension risk (instrumental odds ratio for causal effect per 1 SD lower birthweight, 0.97; 95% CI 0.68 to 1.41). Such results were consistent with that from the summary-level analyses, where the genetically determined low birthweight was not associated with blood pressure measurements either. One SD lower genetically determined birthweight was not associated with systolic blood pressure (β = - 0.76, 95% CI - 2.45 to 1.08 mmHg), 0.06 mmHg lower diastolic blood pressure (β = - 0.06, 95% CI - 0.93 to 0.87 mmHg), or pulse pressure (β = - 0.65, 95% CI - 1.38 to 0.69 mmHg, all p > 0.05). Our findings suggest that the inverse association of birthweight with hypertension risk from observational studies was not supported by large Mendelian randomization analyses.

"Extrauterine growth restriction" and "postnatal growth failure" are misnomers for preterm infants

Preterm infants are increasingly diagnosed as having "extrauterine growth restriction" (EUGR) or "postnatal growth failure" (PGF). Usually EUGR/PGF is diagnosed when weight is <10th percentile at either discharge or 36-40 weeks postmenstrual age. The reasons why the phrases EUGR/PGF are unhelpful include, they: (i) are not predictive of adverse outcome; (ii) are based only on weight without any consideration of head or length growth, proportionality, body composition, or genetic potential; (iii) ignore normal postnatal weight loss; (iv) are usually assessed prior to growth slowing of the reference fetus, around 36-40 weeks, and (v) are usually based on an arbitrary statistical growth percentile cut-off. Focus on EUGR/PGF prevalence may benefit with better attention to nutrition but may also harm with nutrition delivery above infants' actual needs. In this paper, we highlight challenges associated with such arbitrary cut-offs and opportunities for further refinement of understanding growth and nutritional needs of preterm neonates.

Are birthweight and postnatal weight gain in childhood associated with blood pressure in early adolescence? Results from a Ugandan birth cohort

BACKGROUND

In Africa, where low birthweight (LBW), malnutrition and high blood pressure (BP) are prevalent, the relationships between birthweight (BW), weight gain and BP later in life remain uncertain. We examined the effects of early life growth on BP among Ugandan adolescents.

METHODS

Data were collected prenatally from women and their offspring were followed from birth, with BP measured following standard protocols in early adolescence. Weight-for-age Z-scores (WAZ) were computed using World Health Organization references. Linear regression was used to relate BW, and changes in WAZ between birth and 5 years, to adolescents' BP, adjusting for confounders.

RESULTS

Among 2345 live offspring, BP was measured in 1119 (47.7%) adolescents, with mean systolic BP 105.9 mmHg and mean diastolic BP 65.2 mmHg. There was little evidence of association between BW and systolic [regression coefficient β = 0.14, 95% confidence interval (CI) (-1.00, 1.27)] or diastolic [β = 0.43, 95% CI (-0.57, 1.43)] BP. Accelerated weight gain between birth and 5 years was associated with increased BP: systolic β = 1.17, 95% CI (0.69, 1.66) and diastolic β = 1.03, 95% CI (0.59, 1.47). Between birth and 6 months of age, effects of accelerated weight gain on adolescent BP were strongest among the LBW (both premature and small-for-gestational-age) children [BW < 2.5 kg: β = 2.64, 95% CI (0.91, 4.37), BW≥2.5 kg: β = 0.58, 95% CI (0.01, 1.14), interaction P-value =  0.024].

CONCLUSIONS

Findings from this large tropical birth cohort in Uganda suggest that postnatal weight gain rather than BW is important in the developmental programming of BP, with fast-growing LBW children at particular risk. Efforts to control BP should adopt a life course approach.

Perceptions and practices related to birthweight in rural Bangladesh: Implications for neonatal health programs in low- and middle-income settings

BACKGROUND

Globally, low birthweight (LBW) infants (<2.5 kilograms) contribute up to 80% of neonatal mortality. In Bangladesh, approximately 62% of all births occur at home and therefore, weighing newborns immediately after birth is not feasible. Thus, estimates of birthweight in Bangladesh are mostly obtained based on maternal perception of the newborn's birth size. Little is known about how birthweight is perceived in rural communities, and whether families associate birthweight with newborn's health status. Our objective was to explore families' perceptions of newborn's birthweight, and preventive and care practices for a LBW newborn in rural Bangladesh.

METHODS

We conducted a qualitative study in two rural settings of Bangladesh, including 32 in-depth interviews (11 with pregnant women, 12 with recently delivered women, 4 with husbands whose wives were pregnant or had a recent birth, 5 with mothers-in-law whose daughters-in-law were pregnant or had a recent birth), 2 focus group discussions with husbands and 4 key-informant interviews with community health workers. We used thematic analysis to analyse the data.

RESULTS

Most participants did not consider birthweight a priority for assessing a newborn's health status, although there was a desire for a healthy newborn. Recognition of different categories of birthweight was subjective and often included several physical descriptors including birth size of the newborn. LBW was not considered as a criterion of a newborn's illness unless the newborn appeared unwell. Maternal poor nutrition, inadequate diet in pregnancy, anaemia, illness during pregnancy, short stature, twin births and influence of supernatural spirit were identified as the major causes of LBW. Women's preventive practices for LBW or small newborns were predominantly constrained by a lack of awareness of birthweight and fear of caesarean section. As an effort to avoid caesarean section during birth, several women tended to perform potentially harmful practices in order to give birth to a small size newborn; such as avoiding nutritious food and eating less in pregnancy. Common practices to treat a LBW or small newborn who appeared ill included breastfeeding, feeding animal milk, feeding sugary water, feeding formula, oil massage, keeping the small newborn warm and seeking care from formal and informal care providers including a spiritual leader. Maternal lack of decision-making power, financial constraint, home birth and superstition were the major challenges to caring for a LBW newborn.

CONCLUSION

Birthweight was not well-understood in the rural community, which highlighted substantial challenges to the prevention and care practices of LBW newborns. Community-level health education is needed to promote awareness related to the recognition of birthweight in rural settings.

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.

Anthropometric and Biochemical Predictors for Hypertension in a Cross-Sectional Study in Zanzibar, Tanzania

Background: Aim of this study was to describe the proportion of hypertension among Zanzibari of different age-groups and to detect possible correlates of this non-communicable disease.

Methods: In 2013 a cross-sectional survey was conducted in Unguja Island, Zanzibar. A total of 235 randomly selected households, including 1,229 (2 to 95 years) eligible study participants, were examined. Association between objectively assessed obesity markers, salt intake and hypertension were investigated. Estimates of 24 h sodium and potassium excretion from a single morning spot urine specimen were calculated and used as surrogate for salt intake. The association between overweight/obesity and hypertension in different age-groups was assessed in multilevel logistic regression models. Further associations between salt intake and hypertension were analyzed.

Results: Measures of systolic and diastolic blood pressure as well as proportion of overweight/obesity and hypertension both increased with age. Overweight and obesity were significantly associated with hypertension in adults. Moreover, thinness seems to be associated with hypertension as well. We observed a significantly reduced chance of hypertension for higher urinary sodium-to-potassium compared to a lower ratio in children.

Conclusion: Overweight/obesity and hypertension were highly prevalent (>47% of adults >40 years are overweight or obese and >69% are hypertensive in the same age group) in our sample. Weight status was confirmed as a correlate of high blood pressure in our sample from Zanzibar, Tanzania. To early and effectively prevent related severe cardiovascular outcomes, screening strategies but also monitoring strategies are required for this population.

Serum metabolic profile characteristics of offspring rats before and after birth caused by prenatal caffeine exposure

Epidemiological investigations have confirmed that prenatal caffeine intake could increase the incidence rate of intrauterine growth retardation (IUGR) and multiple diseases after birth. Based on liquid chromatography-mass spectrometry, we analyzed serum metabolic profiles of offspring rats before and after birth in IUGR model induced by prenatal caffeine exposure (PCE). We discovered that differential metabolites in PCE fetuses mainly manifested as amino acids and lipid metabolism. In adulthood, PCE offspring showed less and inconsistent types of differential metabolites compared to those in utero, which still exhibited gender differences. The main differential metabolites induced by PCE, including phospholipids, platelet-activating factor, arachidonic acid, bile acid, sphingosine-1-phosphoric acid, indoxyl sulfuric acid, and cortexolone, may participate in the pathological and physiological processes of organ toxicities. This study demonstrated the short- and long-term developmental toxicity and gender differences of caffeine, providing new ideas for exploring the early warning and drug intervention targets of IUGR offspring.

Arterial Structural and Functional Characteristics at End of Early Childhood and Beginning of Adulthood: Impact of Body Size Gain during Early, Intermediate, Late and Global Growth

An association between nutritional characteristics in theearlylife stages and the state of the cardiovascular (CV) system in early childhood itself and/or at the beginning of adulthood has been postulated. It is still controversial whether changes in weight, height and/or body mass index (BMI) during childhood or adolescence are independently associated with hemodynamics and/or arterial properties in early childhood and adulthood. Aims: First, to evaluate and compare the strength of association between CVproperties (at 6 and 18 years (y)) and (a) anthropometric data at specific growth stages (e.g., birth, 6 y, 18 y) and (b) anthropometric changes during early (0–2 y), intermediate (0–6 y), late (6–18 y) and global (0–18 y) growth. Second, to determine whether the associations between CVproperties and growth-related body changes depend on size at birth and/or at the time of CVstudy. Third, to analyze the capacity of growth-related body size changes to explain hemodynamic and arterial properties in early childhood and adulthood before and after adjusting for exposure to CV risk factors. Anthropometric, hemodynamic (central, peripheral) and arterial parameters (structural, functional; elastic, transitional and muscular arteries) were assessed in two cohorts (children, n = 682; adolescents, n = 340). Data wereobtained and analyzed following identical protocols. Results: Body-size changes in infancy (0–2 y) and childhood (0–6 y) showed similar strength of association with CV properties at 6 y. Conversely, 0–6, 6-18 or 0–18 ychanges were not associated with CV parameters at 18 y. The association between CV properties at 6 yand body-size changes during growth showed: equal or greater strength than the observed for body-size at birth, and lower strength compared to that obtained for current z-BMI. Conversely, only z-BMI at 18 y showed associations with CV z-scores at 18 y. Body size at birth showed almost no association with CVproperties at 6 or 18 y. Conclusion: current z-BMI showed the greatest capacity to explain variations in CV properties at 6 and 18 y. Variations in some CV parameters were mainly explained by growth-related anthropometric changes and/or by their interaction with current z-BMI. Body size at birth showed almost no association with arterial properties at 6 or 18 y.

The Long-Lasting Influenza: The Impact of Fetal Stress During the 1918 Influenza Pandemic on Socioeconomic Attainment and Health in Sweden, 1968-2012

The 1918 influenza pandemic had not only a massive instant death toll but also lasting effects on its survivors. Several studies have shown that children born in 1919, and thus exposed to the H1N1 virus in utero, experienced worse health and socioeconomic outcomes in older ages than surrounding birth cohorts. This study combines several sources of contemporary statistics with full-population individual-level data for Sweden during 1968-2012 to examine the influence of fetal exposure to the Spanish flu on health, adulthood income, and occupational attainment. For both men and women, fetal exposure resulted in higher morbidity in ages 54-87, as measured by hospitalization. For males, exposure during the second trimester also affected mortality in cancer and heart disease. Overall, the effects on all-cause mortality were modest, with about three months shorter remaining life expectancy for the cohorts exposed during the second trimester. For socioeconomic outcomes, results fail to provide consistent evidence supporting any long-term consequences of fetal exposure. We conclude that although the immediate health effects of exposure to the 1918 pandemic were huge, the long-term effects were modest in size.

Short-term and long-term distributional consequences of prenatal malnutrition and stress: using Ramadan as a natural experiment

INTRODUCTION

Fetal environments play significant roles in determining adult well-being, particularly as they relate to non-communicable diseases and skill formation. We studied gender-specific distributional consequences of fetal environment (in the form of in-utero exposure to Ramadan, the Islamic holy month of fasting), in Indonesia, on birth weights, performance on Raven's Colored Progressive Matrices (CPM), math scores, hours worked and earnings.

METHODS

We used quantile regressions to conduct a quantitative comparison of distributional consequences, by gender, of full month exposures to Ramadan in-utero on outcomes of interest. Our data included Muslim children and adults measured during rounds 1 and 4 of the Indonesian Family Life Survey. Our main outcome measures were: birth weights-559 observations (females) and 624 (males); Raven's CPM scores-1693 (females) and 1821 (males) for 8-15 year olds; math test scores-1696 (females) and 1825 (males) for 8-15 year olds; hours worked-3181 (females) and 4599 (males) for 18-65 year olds; earnings-2419 (females) and 4019 (males) for 18-65 year olds.

RESULTS

Full month of exposure to Ramadan in-utero led to significant reductions at the 5% significance level that were concentrated in the bottom halves of the outcome distributions: among 8-15 years, lower scores on Raven's CPM tests for females (mean: -9.2%, 10thQ: -19%, 25th Q: -19.4%) and males (mean: -5.6%, 10thQ: -12.5%); lower math scores for females (mean: -8.6%, 25thQ: -15.9%) and males (mean: -8.5%, 10thQ: -13.6%); among females 18-65 years, significant reduction in hours worked (mean: -7.5%, 10thQ: - 26.3%).

CONCLUSION

Events during the fetal period have far-reaching consequences for females and males in the lowest (10th and 25th) quantiles of outcome distributions, affecting the 'relatively poor' the most. These results call for caution in interpreting studies on child development that rely on mean comparisons alone.