The fetal origin of adult disease: from sceptic to convert

When a birth cohort grows up: challenges and opportunities in longitudinal developmental origins of health and disease (DOHaD) research

High-quality evidence from prospective longitudinal studies in humans is essential to testing hypotheses related to the developmental origins of health and disease. In this paper, the authors draw upon their own experiences leading birth cohorts with longitudinal follow-up into adulthood to describe specific challenges and lessons learned. Challenges are substantial and grow over time. Long-term funding is essential for study operations and critical to retaining study staff, who develop relationships with participants and hold important institutional knowledge and technical skill sets. To maintain contact, we recommend that cohorts apply multiple strategies for tracking and obtain as much high-quality contact information as possible before the child's 18th birthday. To maximize engagement, we suggest that cohorts offer flexibility in visit timing, length, location, frequency, and type. Data collection may entail multiple modalities, even at a single collection timepoint, including measures that are self-reported, research-measured, and administrative with a mix of remote and in-person collection. Many topics highly relevant for adolescent and young adult health and well-being are considered to be private in nature, and their assessment requires sensitivity. To motivate ongoing participation, cohorts must work to understand participant barriers and motivators, share scientific findings, and provide appropriate compensation for participation. It is essential for cohorts to strive for broad representation including individuals from higher risk populations, not only among the participants but also the staff. Successful longitudinal follow-up of a study population ultimately requires flexibility, adaptability, appropriate incentives, and opportunities for feedback from participants.

An analysis of the distribution and spectrum of alpha thalassemia mutations in Rasht City, North of Iran

Background

Alpha thalassemia is one of the most common hereditary hemoglobin disorders worldwide, particularly in the Middle East, including Iran. Therefore, determining the spectrum and distribution of alpha thalassemia mutation is a fundamental component of preventive approaches and management strategies.

Methods

The present study reviews the genetic testing and blood laboratory results of 455 candidates eligible for marriage who were suspected of being thalassemia carriers and on whom genetic testing was performed from 21 March 2013 to 31 December 2020 in Rasht City.

Results

A total of 114 (25.05%) alpha thalassemia cases were identified. Fifteen different alpha mutations were found. The most common mutation among the study population was -α^3.7 deletion in 55 patients (48.24%), followed by Hb Constant Spring (C.S) in 21 patients (18.42%) and poly A2 in 16 (14.03%). Also, most of the patients were silent carriers. The deletion type of mutation was much more common than non-deletion mutations.

Conclusion

Our study reveals genetic heterogeneity and alpha thalassemia diversity among the Rasht City population. We expect that these findings will help guide premarital screening and genetic counseling, prenatal diagnosis of thalassemia, preventive strategy development, as well as a compilation of the alpha thalassemia catalog in Guilan province.

Placental insufficiency induces a sexually dimorphic response in the expression of cardiac growth and metabolic signalling molecules upon exposure to a postnatal western diet in guinea pigs

There is a strong relationship between low birth weight (LBW) and an increased risk of developing cardiovascular disease (CVD). In postnatal life, LBW offspring are becoming more commonly exposed to the additional independent CVD risk factors, such as an obesogenic diet. However, how an already detrimentally programmed LBW myocardium responds to a secondary insult, such as an obesogenic diet (western diet; WD), during postnatal life is ill defined. Herein, we aimed to determine in a pre-clinical guinea pig model of CVD, both the independent and interactive effects of LBW and a postnatal WD on the molecular pathways that regulate cardiac growth and metabolism. Uterine artery ablation was used to induce placental insufficiency (PI) in pregnant guinea pigs to generate LBW offspring. Normal birth weight (NBW) and LBW offspring were weaned onto either a Control diet or WD. At ˜145 days after birth (young adulthood), male and female offspring were humanely killed, the heart weighed and left ventricle tissue collected. The mRNA expression of signalling molecules involved in a pathological hypertrophic and fibrotic response was increased in the myocardium of LBW male, but not female offspring, fed a WD as was the mRNA expression of transcription factors involved in fatty acid oxidation. The mRNA expression of glucose transporters was downregulated by LBW and WD in male, but not female hearts. This study has highlighted a sexually dimorphic cardiac pathological hypertrophic and fibrotic response to the secondary insult of postnatal WD consumption in LBW offspring.

Fetal Growth Restriction and Asthma: Is the Damage Done?

Trajectories of airway remodeling and functional impairment in asthma are consistent with the notion that airway pathology precedes or coincides with the onset of asthma symptoms and may be present at birth. An association between intrauterine growth restriction (IUGR) and asthma development has also been established, and there is value in understanding the underlying mechanism. This review considers airway pathophysiology as a consequence of IUGR that increases susceptibility to asthma.

Mediation of the association between maternal pre-pregnancy overweight/obesity and childhood overweight/obesity by birth anthropometry

The mechanism through which developmental programming of offspring overweight/obesity following in utero exposure to maternal overweight/obesity operates is unknown but may operate through biologic pathways involving offspring anthropometry at birth. Thus, we sought to examine to what extent the association between in utero exposure to maternal overweight/obesity and childhood overweight/obesity is mediated by birth anthropometry. Analyses were conducted on a retrospective cohort with data obtained from one hospital system. A natural effects model framework was used to estimate the natural direct effect and natural indirect effect of birth anthropometry (weight, length, head circumference, ponderal index, and small-for-gestational age [SGA] or large-for-gestational age [LGA]) for the association between pre-pregnancy maternal body mass index (BMI) category (overweight/obese vs normal weight) and offspring overweight/obesity in childhood. Models were adjusted for maternal and child socio-demographics. Three thousand nine hundred and fifty mother-child dyads were included in analyses (1467 [57.8%] of mothers and 913 [34.4%] of children were overweight/obese). Results suggest that a small percentage of the effect of maternal pre-pregnancy BMI overweight/obesity on offspring overweight/obesity operated through offspring anthropometry at birth (weight: 15.5%, length: 5.2%, head circumference: 8.5%, ponderal index: 2.2%, SGA: 2.9%, and LGA: 4.2%). There was a small increase in the percentage mediated when gestational diabetes or hypertensive disorders were added to the models. Our study suggests that some measures of birth anthropometry mediate the association between maternal pre-pregnancy overweight/obesity and offspring overweight/obesity in childhood and that the size of this mediated effect is small.

Cardiorespiratory consequences of intrauterine growth restriction: Influence of timing, severity and duration of hypoxaemia

At birth, weight of the neonate is used as a marker of the 9-month journey as a fetus. Those neonates born less than the 10th centile for their gestational age are at risk of being intrauterine growth restricted. However, this depends on their genetic potential for growth and the intrauterine environment in which they grew. Alterations in the supply of oxygen and nutrients to the fetus will decrease fetal growth, but these alterations occur due to a range of causes that are maternal, placental or fetal in nature. Consequently, IUGR neonates are a heterogeneous population. For this reason, it is likely that these neonates will respond differently to interventions compared not only to normally grown fetuses, but also to other neonates that are IUGR but have travelled a different path to get there. Thus, a range of models of IUGR should be studied to determine the effects of IUGR on the development and function of the heart and lung and subsequently the impact of interventions to improve development of these organs. Here we focus on a range of models of IUGR caused by manipulation of the maternal, placental or fetal environment on cardiorespiratory outcomes.

Prenatal diagnosis and management of homozygous hemoglobin constant spring disease

OBJECTIVE

To describe fetal management of homozygous hemoglobin constant spring (Hb CS).

METHODS

Six fetuses with homozygous Hb CS disease undergoing intrauterine transfusion (IUT) were comprehensively reviewed. Additionally, when combined with 8 cases previously reported, a total of 14 cases were analyzed.

RESULTS

The first clues of diagnosis were hydropic changes suggesting fetal anemia. Increased cardiothoracic diameter ratio (CTR) was the most sensitive sonographic marker but slowly changed after IUT, whereas MCA-PSV was the most sensitive in response to IUT. Pre-IUT Hb varied from 1.1% to 6.8%. Gestational age at diagnosis was 17-29 (22.8 ± 3.3) weeks. Rates of adverse obstetric outcomes were relatively high; preterm birth: 35.7%, low birthweight: 42.9%, and fetal growth restriction: 28.6%. All showed good response to IUT with disappearance of hydropic signs and all survived without short-term complications. Their anemia gradually improved in childhood and transfusion independent.

CONCLUSION

Homozygous Hb CS can cause severe fetal anemia. Early diagnosis and IUT can improve neonatal outcomes, probably preventing adult diseases caused by fetal programming.

In utero exposure to tobacco smoke, subsequent cardiometabolic risks, and metabolic syndrome among U.S. adolescents

PURPOSE

Maternal smoking during pregnancy increases risk of adverse pregnancy outcomes. However, little is known regarding in utero smoke exposure and offspring cardiometabolic risk. Thus, we examined the association between in utero smoke exposure and cardiometabolic risk factors and the metabolic syndrome (MetS) in adolescents.

METHODS

Participants included 7464 adolescents aged 12-15 years identified from the National Health and Nutrition Examination Survey (1999-2014). Multiple logistic and linear regression analyses estimated sex-specific means and odds ratios (ORs) for the association between in utero smoke exposure and MetS and cardiometabolic risk factors.

RESULTS

MetS prevalence was 9.0% in exposed versus 5.9% in unexposed adolescents. In utero smoke exposure was significantly associated with increased odds of MetS among males in models controlling for adolescent age, maternal age, and race/ethnicity (OR: 2.48, 95% confidence interval: 1.19, 5.20), with attenuation of this effect in subsequent models. In utero smoke exposure was associated with significantly elevated mean body mass index and waist circumference percentiles among female adolescents across most models in regression analyses.

CONCLUSIONS

In utero smoke exposure appears to be associated with an increased likelihood of high waist circumference and body mass index percentiles, especially among female adolescents. Our study demonstrates the long-term cardiometabolic impact in offspring, highlighting the importance of prepregnancy smoking cessation.

Starvation during pregnancy impairs fetal oogenesis and folliculogenesis in offspring in the mouse

Although it is becoming increasingly evident that maternal starvation during pregnancy can have permanent effects on a range of physiological processes in the offspring, scant information is available about the consequence of such condition for oogenesis and hence for lifetime reproductive success of progeny in mammals. In the present study, we address this topic by starving pregnant mice at the time of ovarian differentiation (12.5 days post coitum (dpc)) for three consecutive days and analyzed the consequence first on the survival of the fetal oocytes and their capability to progress throughout the stages of meiotic prophase I (MPI) and then on the postnatal folliculogenesis of the offspring. The results showed that maternal starvation increased apoptosis in the fetal ovaries, resulting in reduction of the oocyte number. Moreover, MPI progression was slowed down in the surviving oocytes and the expression of DNA repair players in the starved ovaries increased. Transcriptome analysis identified 61 differentially expressed genes between control and starved ovaries, the most part of these being involved in metabolic processes. A significant decrease in the percentage of oocytes enclosed in primordial follicles and the expression of oocyte genes critically involved in folliculogenesis such as Nobox, Lhx8 and Sohlh2 in the 3 days post partum (dpp) starved ovaries were found. Finally, at the time of juvenile period (21 dpp), the number of oocytes and antral follicles resulted significantly lower in the ovaries of the offspring from starved mothers in comparison to controls. Our findings support the notion that maternal starvation can affect ovary development in the offspring that could adversely affect their reproductive success in the adult life.

Bagaimana Gizi Sejak Massa Konsepsi Dapat Mempengaruhi Kesehatan Biologis Anak?

Background: good nutrition for mothers since pre-conception and conception is an important preparation for the health of the fetus and the child in the future.Objective: The purpose in writing this literature review is to explain argumentatively how nutrition from the time of conception can affect the child's biological health.Discussion: The results of the literature review show evidence that nutrition from the time of conception can affect the child's biological health. Several articles show a mechanism that explains the possible mechanisms of nutritional influence as conception on the child's biological health as in the future as Barker Hyphothesis or fetal programming. However, the data obtained to date is still not fully convincing. It is necessary to develop a long or longitudinal and experimental research that can guarantee the truth of the theory. Conclusion: the argument that nutrition from the time of conception is believed to affect the biological health of children in the future is increasingly stronger in the current literature although evidence of experimental research results still need to be accumulated to ensure the truth.ABSTRAK Latar Belakang: gizi yang baik bagi ibu sejak masa pra konsepsi dan konsepsi merupakan persiapan yang penting untuk kesehatan janin dan anak dimasa dating. Tujuan: tujuan dalam penulisan literature review ini adalah untuk menjelaskan secara argumentative bagaimana gizi sejak masa konsepsi dapat mempengaruhi kesehatan biologis anak. Pembahasan: hasil literature review menunjukkan bukti bahwa gizi sejak masa konsepsi dapat mempengaruhi kesehatan biologis anak. Beberapa artikel menunjukkan mekanisme yang menjelaskan kemungkinan mekanisme pengaruh gizi saat konsepsi terhadap kesehatan biologis anak dimasa datang seperti halnya Barker Hyphothesis atau fetal programming. Namun begitu, data yang diperoleh hingga saat ini masih belum meyakinkan sepenuhnya. Untuk itu perlu dikembangkan penelitian yang panjang atau longitudinal dan eksperimental yang dapat menggaransi kebenaran teori tersebut.Kesimpulan: argumentasi bahwa gizi sejak masa konsepsi diyakini berpengaruh terhadap kesehatan biologis anak dimasa depan semakin menguat dalam literature terkini walaupun bukti hasil penelitian eksperimental masih perlu banyak diakumulasikan untuk memastikan kebenarannya. ABSTRAKLatar Belakang: gizi yang baik bagi ibu sejak masa pra konsepsi dan konsepsi merupakan persiapan yang penting untuk kesehatan janin dan anak dimasa dating. Tujuan: tujuan dalam penulisan literature review ini adalah untuk menjelaskan secara argumentative bagaimana gizi sejak masa konsepsi dapat mempengaruhi kesehatan biologis anak. Pembahasan: hasil literature review menunjukkan bukti bahwa gizi sejak masa konsepsi dapat mempengaruhi kesehatan biologis anak. Beberapa artikel menunjukkan mekanisme yang menjelaskan kemungkinan mekanisme pengaruh gizi saat konsepsi terhadap kesehatan biologis anak dimasa datang seperti halnya Barker Hyphothesis atau fetal programming. Namun begitu, data yang diperoleh hingga saat ini masih belum meyakinkan sepenuhnya. Untuk itu perlu dikembangkan penelitian yang panjang atau longitudinal dan eksperimental yang dapat menggaransi kebenaran teori tersebut. Kesimpulan: argumentasi bahwa gizi sejak masa konsepsi diyakini berpengaruh terhadap kesehatan biologis anak dimasa depan semakin menguat dalam literature terkini walaupun bukti hasil penelitian eksperimental masih perlu banyak diakumulasikan untuk memastikan kebenarannya.

Rates of obstetric intervention during birth and selected maternal and perinatal outcomes for low risk women born in Australia compared to those born overseas

BACKGROUND

There are mixed reports in the literature about obstetric intervention and maternal and neonatal outcomes for migrant women born in resource rich countries. The aim of this study was to compare the risk profile, rates of obstetric intervention and selected maternal and perinatal outcomes for low risk women born in Australia compared to those born overseas.

METHOD

A population-based descriptive study was undertaken in NSW of all singleton births recorded in the NSW Midwives Data Collection between 2000-2008 (n=691,738). Risk profile, obstetric intervention rates and selected maternal and perinatal outcomes were examined.

RESULTS

Women born in Australia were slightly younger (30 vs 31 years), less likely to be primiparous (41% vs 43%), three times more likely to smoke (18% vs 6%) and more likely to give birth in a private hospital (26% vs 18%) compared to women not born in Australia. Among the seven most common migrant groups to Australia, women born in Lebanon were the youngest, least likely to be primiparous and least likely to give birth in a private hospital. Hypertension was lowest amongst Vietnamese women (3%) and gestational diabetes highest amongst women born in China (14%). The highest caesarean section (31%), instrumental birth rates (16%) and episiotomy rates (32%) were seen in Indian women, along with the highest rates of babies <10th centile (22%) and <3rd centile (8%). Lebanese women had the highest rates of stillbirth (7.2/1000). Similar trends were found in the different migrant groups when only low risk women were included.

CONCLUSION

The results suggest there are significant differences in risk profiles, obstetric intervention rates and maternal and neonatal outcomes between Australian-born and women born overseas and these differences are seen overall and in low risk populations. The finding that Indian women (the leading migrant group to Australia) have the lowest normal birth rate and high rates of low birth weight babies is concerning, and attention needs to be focused on why there are disparities in outcomes and on effective models of care that might improve outcomes for this population.

The fetal origins of adult disease: a narrative review of the epidemiological literature

The fetal origins of adult disease (FOAD) hypothesis suggests that risk factors from intrauterine environmental exposures affect the fetus' development during sensitive periods, and increases the risk of specific diseases in adult life. This link was initially observed between prenatal exposures and adult coronary heart disease, but corresponding observations have later been published for a range of chronic conditions. Although the hypothesis has been praised as an essential shift in our understanding of determinants for health, the hypothesis has also been criticized on a number of accounts, both methodologically and theoretically. The aim of this paper is to critically discuss the FOAD-hypothesis, in relation to the epidemiological evidence. We conclude that much of the research literature on the FOAD-hypothesis finds support for the hypothesis. Despite this, it is still unclear if the effects are independent and what the public health relevance is. Notwithstanding the heart of the hypothesis – that environmental influences during gestation have an effect on later development – should be considered a major insight and constitutes a complement to a focus on genetic and more proximal factors (such as adult lifestyle) as causes of adult disease. As the search for determinants for disease and health continues, the FOAD-hypothesis is likely to remain an important perspective. It may however be better positioned as part of a broader life course perspective, rather than as an independent hypothesis.

Investigating maternal risk factors as potential targets of intervention to reduce socioeconomic inequality in small for gestational age: a population-based study

BACKGROUND

The major aim of this study was to investigate whether maternal risk factors associated with socioeconomic status and small for gestational age (SGA) might be viable targets of interventions to reduce differential risk of SGA by socioeconomic status (socioeconomic SGA inequality) in the metropolitan area of Vancouver, Canada.

METHODS

This study included 59,039 live, singleton births in the Vancouver Census Metropolitan Area (Vancouver) from January 1, 2006 to September 17, 2009. To identify an indicator of socioeconomic SGA inequality, we used hierarchical logistic regression to model SGA by area-level variables from the Canadian census. We then modelled SGA by area-level average income plus established maternal risk factors for SGA and calculated population attributable SGA risk percentages (PAR%) for each variable. Associations of maternal risk factors for SGA with average income were investigated to identify those that might contribute to SGA inequality. Finally, we estimated crude reductions in the percentage and absolute differences in SGA risks between highest and lowest average income quintiles that would result if interventions on maternal risk factors successfully equalized them across income levels or eliminated them altogether.

RESULTS

Average income produced the most linear and statistically significant indicator of socioeconomic SGA inequality with 8.9% prevalence of SGA in the lowest income quintile compared to 5.6% in the highest. The adjusted PAR% of SGA for variables were: bottom four quintiles of height (51%), first birth (32%), bottom four quintiles of average income (14%), oligohydramnios (7%), underweight or hypertension, (6% each), smoking (3%) and placental disorder (1%). Shorter height, underweight and smoking during pregnancy had higher prevalence in lower income groups. Crude models assuming equalization of risk factors across income levels or elimination altogether indicated little potential change in relative socioeconomic SGA inequality and reduction in absolute SGA inequality for shorter height only.

CONCLUSIONS

Our findings regarding maternal height may indicate trans-generational aetiology for socioeconomic SGA inequalities and/or that adult height influences social mobility. Conditions affecting foetal and childhood growth might be viable targets to reduce absolute socioeconomic SGA inequality in future generations, but more research is needed to determine whether such an approach is appropriate.

Adult onset lung disease following transient disruption of fetal stretch-induced differentiation

One of the mechanisms by which adult disease can arise from a fetal origin is by in utero disruption of organogenesis. These studies were designed to examine respiratory function changes in aging rats following transient disruption of lung growth at 16 days gestation. Fetuses were treated in utero with a replication deficient adenovirus containing the cystic fibrosis conductance transmembrane regulator (CFTR) gene fragment cloned in the anti-sense direction. The in utero-treated rats demonstrated abnormal lung function beginning as early as 30 days of age and the pathology progressed as the animals aged. The pulmonary function abnormalities included decreased static compliance as well as increased conducting airway resistance, tissue damping, and elastance. Pressure volume (PV) curves demonstrated a slower early rise to volume and air trapping at end-expiration. The alterations of pulmonary function correlated with lung structural changes determined by morphometric analysis. These studies demonstrate how transient disruption of lung organogensis by single gene interference can result in progressive change in lung function and structure. They illustrate how an adult onset disease can arise from subtle changes in gene expression during fetal development.

The effects of socioeconomic status and indices of physical environment on reduced birth weight and preterm births in Eastern Massachusetts

BACKGROUND

Air pollution and social characteristics have been shown to affect indicators of health. While use of spatial methods to estimate exposure to air pollution has increased the power to detect effects, questions have been raised about potential for confounding by social factors.

METHODS

A study of singleton births in Eastern Massachusetts was conducted between 1996 and 2002 to examine the association between indicators of traffic, land use, individual and area-based socioeconomic measures (SEM), and birth outcomes (birth weight, small for gestational age and preterm births), in a two-level hierarchical model.

RESULTS

We found effects of both individual (education, race, prenatal care index) and area-based (median household income) SEM with all birth outcomes. The associations for traffic and land use variables were mainly seen with birth weight, with an exception for an effect of cumulative traffic density on small for gestational age. Race/ethnicity of mother was an important predictor of birth outcomes and a strong confounder for both area-based SEM and indices of physical environment. The effects of traffic and land use differed by level of education and median household income.

CONCLUSION

Overall, the findings of the study suggested greater likelihood of reduced birth weight and preterm births among the more socially disadvantaged, and a greater risk of reduced birth weight associated with traffic exposures. Results revealed the importance of controlling simultaneously for SEM and environmental exposures as the way to better understand determinants of health.

Developmental origins theory from prematurity to adult disease

Developmental Origins Theory has received little coverage in the nursing literature, even though it has received much attention in other sciences. The theory proposes that prenatal stress provokes adaptive changes in endocrine and metabolic processes that become permanently programmed and impact later adult health. This paper reviews the theory and describes the primary neuroendocrine mechanism of hypothalamic-pituitary-adrenal axis function. Supporting research evidence in preterm infant and adult samples is presented. Through knowledge of the theory and the long-term sequelae for preterm infants, nurses will have a different theoretical perspective and growing evidence to consider in their care for pregnant women and infants.

Standards for the measurement of birth weight, length and head circumference at term in neonates of European, Chinese and South Asian ancestry

BACKGROUND

Fetal growth restriction is associated with metabolic derangements in the newborn, impaired functioning in childhood and chronic diseases in adulthood. Differences between ethnic groups with respect to fetal growth may result in the misclassification of constitutionally small or large babies as having abnormal growth for their gestational age. We have developed intrauterine growth charts based on precise measurements of newborns whose parents were both of European, Chinese or South Asian ethnicity.

METHODS

Weight, length and head circumference were measured in 2695 infants born to healthy non-smoking mothers in British Columbia at 37-41 completed weeks of gestation. Gestational age was confirmed by ultrasound before 20 weeks of gestation. Weight was measured by digital scale, length by stadiometer and head circumference by firm plastic tape measures. Means and 95% confidence intervals were compared among newborns grouped by ethnicity and sex. Smoothed graphs were constructed for visual interpretation.

RESULTS

At 40 weeks, infants of European descent ("European" infants) weighed 225.5 g more on average than infants of Chinese descent ("Chinese" infants) (p < 0.001) and 254.6 g more than infants of South Asian descent ("South Asian" infants) (p < 0.001). The mean difference in birth weight between Chinese and South Asian infants (19.1 g) was not statistically significant. The mean length of European infants at 40 weeks of gestation was 0.89 cm greater than that of Chinese infants (p < 0.001). Differences in mean length between European and South Asian babies or between Chinese and South Asian babies was not statistically significant. The mean head circumferance of European babies was 0.50 cm larger than that of Chinese babies at 40 weeks (p < 0.001) but did not differ significantly from that of South Asian babies. South Asian and Chinese babies had similar mean head circumferences at 40 weeks. When differences in mean birth weight, length and head circumference were examined within boys and girls, the observed differences according to ethnicity remained statistically significant.

CONCLUSION

Important differences in weight, length and head circumferences are reported among babies according to ethnicity. The use of sex- and ethnicity-specific growth charts may prevent the misclassification of newborns as small or large for gestational age.

What is the effect of adjusting for more than one measure of current body size on the relation between birthweight and blood pressure?

The statistical validity of the negative associations observed between birthweight and disease in later life has recently been questioned, because these associations might be due, in part, to inappropriate adjustment for current body size, creating a statistical artefact known as the 'reversal paradox'. The aim of this study was to explore the effect of adjusting for more than one measure of current body size on the association between birthweight and disease in later life using simulations and meta-analyses of empirical studies. The simulations examined the relation between birthweight and adult systolic blood pressure before and after adjusting for one, two or three measures of current body size by including current weight and subsequently adding body mass index and height in successive analytical models. Meta-analyses were then performed to compare the effect sizes observed among empirical studies reporting associations between birthweight and blood pressure before and after adjusting for one or two measures of current body size. The meta-analyses confirmed the results of the simulations - both showed that associations between birthweight and blood pressure tend to become increasingly negative following adjustment for current body size, and that this effect is enhanced after adjusting for additional measures of current body size.

Embryonic and fetal programming of physiological disorders in adulthood

In the past decade, data from numerous epidemiological studies have indicated strong inverse associations between birth weight and risk of coronary heart disease, hypertension, type 2-diabetes, and other diseases in adulthood. The "Barker hypothesis" thus postulates that a number of organ structures and functions undergo programming during embryonic and fetal life. This developmental programming determines the set points of physiological and metabolic responses in adult life. Alterations of nutrient availability during gestation may lead to developmental adaptations, via hormonal maneuvers by the embryo and fetus that readjust these set points. These adaptive measures have short-term benefits to the embryo and fetus, so that the newborn will be better prepared for the adverse environment (e.g., undernutrition). However, adequate nutritional support during postnatal life that enables catch-up growth may create metabolic conflicts that predispose the adult to aberrant physiological functions and, ultimately, increased risk of disease. It is plausible that other adverse in utero conditions, including exposure to developmental toxicants, may similarly alter adult disease susceptibility. This article provides an overview of the Barker hypothesis, its supporting evidence, the current advances in understanding the biological mechanisms underlying this phenomenon, and its implications for developmental toxicology.

Studies of twins: what can they tell us about the fetal origins of adult disease?

There has been much interest in evidence that people with lower birthweight have higher risk of adult cardiovascular disease, but the causal pathways underlying such observations are uncertain. Study of twins offers an opportunity to shed light on the underlying causal pathways, in particular by investigating the role of 'shared' factors vs. factors affecting each individual fetus. This involves comparing results of within-cohort vs. within-pair analyses. Twins share many factors during gestation but birthweight discordance (difference in birthweight within a twin pair) cannot be determined by these shared factors and must relate to factors affecting growth of each individual fetus. If associations seen in a cohort of twins remain in within-pair analyses, then factors specific to each individual must be involved in the underlying causal pathways. Conversely, if the relationships disappear or substantially diminish in within-pair analyses, then factors common to the pair must be involved. Comparison of findings in monozygotic vs. dizygotic twins may provide insights into the role of genetic factors, although issues related to chorionicity need to be taken into account. We tabulate published data and conclude that differences in methodology and analyses preclude informative meta-analysis, and that analysis of pooled data would provide more useful information.

Translating pharmacogenetics and pharmacogenomics into drug development for clinical pediatrics and beyond

Pharmacogenetic and pharmacogenomic investigations conducted in children must consider that human development from conception through to adolescence is a rapidly changing, dynamic process. An improved understanding of the gene networks that are involved in growth and development and of the unintended consequences of modulating those systems could provide insights into the susceptibility of an individual to drug-induced birth defects and to pediatric adverse drug reactions. Furthermore, these technologies potentially present the opportunity to develop novel, effective treatments for childhood diseases and for adult diseases that manifest primarily during childhood. The lack of pharmacogenetic and pharmacogenomic investigations in children and the potential to impact on all age groups provides a considerable incentive to invest in this area of research.

Combination of low birth weight and high adult body mass index: at what age is it established and what are its determinants?

OBJECTIVE

To investigate growth trajectories and predictive factors for those with low birth weight and high adult BMI.

DESIGN

Birth cohort study.

SETTING

England, Scotland, and Wales.

PARTICIPANTS

All born 3-9 March, 1958.

MAIN OUTCOME MEASURES

People at "high risk" of adult disease were defined as having a combination of lower birth weight (in the lowest third of the distribution) and high BMI (in the highest third of the distribution at age 33).

RESULTS

284 of 3462 men and 338 of 3555 women were identified as "high risk". This group was shorter than other cohort members at age 7, on average by 1.2 cm (boys) and 1.8 cm (girls), with a deficit of about 3 cm in adult height. The "high risk" group had a similar mean weight to other subjects at age 7, but were heavier thereafter through to age 23. BMI was increased at all ages in the "high risk" group. Independent predictors include paternal BMI, maternal height and smoking in pregnancy, and social class. For each SD increase in father's BMI the odds of low birth weight/high BMI increased by about 20%. For maternal height, a 1 cm increase reduced the odds of low birth weight/high BMI by about 5%. Increased ORs for "high risk" were found for those with manual social origins (1.61 for men; 1.49 for women) and for maternal smoking in pregnancy (1.79 and 2.27 respectively).

CONCLUSIONS

Maternal short stature, low social class, and smoking during pregnancy influence the development of "high risk" for adult chronic disease. The causes of high risk therefore seem to reside in utero and even earlier, in the mother's lifetime, with adverse conditions having a detrimental affect and favourable conditions protecting against high risk.

Fetal Neurobehavioral Development: A Tale of Two Cities

Longitudinal neurobehavioral development was examined in 237 fetuses of low-risk pregnancies from 2 distinct populations--Baltimore, Maryland, and Lima. Peru--at 20, 24, 28, 32, 36, and 38 weeks gestation. Data were based on digitized Doppler-based fetal heart rate (FHR) and fetal movement (FM). In both groups. FHR declined while variability, episodic accelerations, and FM-FHR coupling increased, with discontinuities evident between 28 and 32 weeks gestation. Fetuses in Lima had higher FHR and lower variability, accelerations, and FM-FHR coupling. Declines in trajectories were typically observed 1 month sooner in Lima, which magnified these disparities. Motor activity differences were less consistent. No sex differences in fetal neurobehaviors were detected. It is concluded that population factors can influence the developmental niche of the fetus.

Cardiovascular risk factor profiles and their social gradient from adolescence to age 74 in a Swiss region

BACKGROUND

Few European studies have investigated how cardiovascular risk factors (CRF) in adults relate to those observed in younger generations.

OBJECTIVE

To explore this issue in a Swiss region using two population health surveys of 3636 adolescents ages 9-19 years and 3299 adults ages 25-74 years.

METHODS

Age patterns of continuous CRF were estimated by robust locally weighted regression and those of high-risk groups were calculated using adult criteria with appropriate adjustment for children.

RESULTS

Gender differences in height, weight, blood pressure, and HDL cholesterol observed in adults were found to emerge in adolescents. Overweight, affecting 10-12% of adolescents, was increasing steeply in young adults (three times among males and twice among females) in parallel with inactivity. Median age at smoking initiation was decreasing rapidly from 18 to 20 years in young adults to 15 in adolescents. A statistically significant social gradient in disfavor of the lower education level was observed for overweight in all age groups of women above 16 (odds ratios (ORs) 2.4 to 3.3, P < 0.01), for inactivity in adult males (ORs 1.6 to 2.0, P < 0.05), and for regular smoking in older adolescents (OR 1.9 for males, 2.7 for females, P < 0.005), but not for elevated blood pressure.

CONCLUSION

Discontinuities in the cross-sectional age patterns of CRF indicated the emergence of a social gradient and the need for preventive actions against the early adoption of persistent unhealthy behaviors, to which low-educated girls and women are particularly exposed.

Is birthweight a good marker for gestational exposures that increase the risk of adult disease?

There is much evidence of a link between low birthweight and elevated risk of adult cardiovascular disease, from humans and experimental animals. However, if one relies on data linking birthweight to coronary heart disease to estimate the public health implications of this association, the effects are likely to be modest. The focus on birthweight may be misplaced, because reduced size at birth may not be in the causal pathway linking gestational factors to disease in adult offspring. We need to know more about this before we can estimate the public health implications of gestational factors and assess the potential for intervention. The most studied gestational factor is maternal nutrition. We review here evidence for and against birthweight being in the causal pathways between suboptimal maternal nutrition and increased risk of adult disease in the offspring and provide evidence suggesting that birthweight is not in all of them. From a public health point of view, we suggest that future research in this field should focus on modifiable gestational exposures that may be linked to adult disease, whether or not they influence size at birth.

Maternal smoking during pregnancy and severe antisocial behavior in offspring: a review

OBJECTIVES

Recent research suggests that in utero exposure to maternal smoking is a risk factor for conduct disorder and delinquency. We review evidence of causality, a controversial but important public health question.

METHODS

We analyzed studies of maternal prenatal smoking and offspring antisocial behavior within a causal framework.

RESULTS

The association is (1) independent of confounders, (2) present across diverse contexts, and (3) consistent with basic science. Methodological limitations of existing studies preclude causal conclusions.

CONCLUSIONS

Existing evidence provides consistent support for, but not proof of, an etiologic role for prenatal smoking in the onset of antisocial behavior. The possibility of identifying a preventable prenatal risk factor for a serious mental disorder makes further research on this topic important for public health.