Prematurity and programming of cardiovascular disease risk: a future challenge for public health?

Specialized Pro-Resolving Lipid Mediators in Neonatal Cardiovascular Physiology and Diseases

Cardiovascular disease remains a leading cause of mortality worldwide. Unresolved inflammation plays a critical role in cardiovascular diseases development. Specialized Pro-Resolving Mediators (SPMs), derived from long chain polyunsaturated fatty acids (LCPUFAs), enhances the host defense, by resolving the inflammation and tissue repair. In addition, SPMs also have anti-inflammatory properties. These physiological effects depend on the availability of LCPUFAs precursors and cellular metabolic balance. Most of the studies have focused on the impact of SPMs in adult cardiovascular health and diseases. In this review, we discuss LCPUFAs metabolism, SPMs, and their potential effect on cardiovascular health and diseases primarily focusing in neonates. A better understanding of the role of these SPMs in cardiovascular health and diseases in neonates could lead to the development of novel therapeutic approaches in cardiovascular dysfunction.

Very preterm birth results in later lower platelet activation markers

BACKGROUND

Premature birth entails an adverse cardiovascular risk profile, but the underlying mechanisms are insufficiently understood. Here, we employed an unbiased cardiovascular proteomics approach to profile former very preterm-born preschoolers.

METHODS

This observational study investigated differences in plasma concentrations of 79 proteins, including putative cardiovascular biomarkers between very preterm- and term-born children on average 5.5 years old (53.1% male) using multiple-reaction monitoring mass spectrometry.

RESULTS

Very preterm-born (n = 38; median gestational age 29.6 weeks) compared to term-born (n = 26; 40.2 weeks) children featured lower plasma concentrations of platelet factor 4 (PLF4; -61.6%, P < 0.0001), platelet basic protein (CXCL7; -57.8%, P < 0.0001), and hemoglobin subunit beta (-48.3%, P < 0.0001). Results remained virtually unchanged when adjusting for complete blood count parameters, including platelet count. Conversely, whole blood hemoglobin was higher (+7.62%, P < 0.0001) in preterm-born children.

CONCLUSIONS

Very preterm birth was associated with decreased markers of platelet activation among preschoolers. These findings are consistent with reduced platelet reactivity persisting from very preterm birth to a preschool age.

IMPACT

Former very preterm-born preschoolers featured reduced levels of platelet activation markers. While lower platelet reactivity in very preterm-born compared to term-born infants in the first days of life was established, it was unknown when, if at all, reactivity normalizes. The current study suggests that platelet hyporeactivity due to very preterm birth persists at least up to a preschool age. "Immaturity of the hemostatic system" may be a persistent sequel of preterm birth, but larger studies are needed to investigate its potential clinical implications.

Serial assessment of fat and fat-free mass accretion in very preterm infants: a randomized trial

BACKGROUND

Clinicians could modify dietary interventions during early infancy by monitoring fat and fat-free mass accretion in very preterm infants.

METHODS

Preterm infants were randomly assigned to either having reports on infant body composition available to the clinicians caring for them (intervention group) or not having reports available (control group). All infants underwent serial assessments of body composition by air-displacement plethysmography before 32 weeks of postmenstrual age (PMA) and at 36 weeks PMA. The primary outcome was percent body fat (%BF) at 3 months of corrected age (CA).

RESULTS

Fifty infants were randomized (median gestational age: 30 weeks; mean ± SD birth weight: 1387 ± 283 g). The mean %BF increased from 7 ± 4 before 32 weeks PMA to 20 ± 5 at 3 months CA. The differences in mean %BF between the intervention group and the control group were not statistically significant at 36 weeks PMA (14.5 vs. 13.6) or 3 months CA (20.8 vs. 19.4). Feeding practices and anthropometric measurements during hospitalization did not differ between groups.

CONCLUSIONS

Serial assessments of body composition in both intervention and control groups showed consistent increments in %BF. However, providing this information to clinicians did not influence nutritional practices or growth.

IMPACT

Serial assessments of body composition in preterm infants at 32 and 36 weeks postmenstrual age show consistent increments in % body fat up to 3 months of corrected age. However, providing this information to the clinician did not influence nutritional practices or growth.

Apolipoprotein Profiles in Very Preterm and Term-Born Preschool Children

Background

Little is known about plasma apolipoprotein profiles in very preterm‐born and term‐born preschool children compared with the adult population. This is of particular interest because apolipoprotein composition might contribute to cardiometabolic outcome in later life.

Methods and Results

Children aged 5 to 7 years born at term or with <32 weeks of gestation were included. Apolipoprotein concentrations were measured in plasma collected after an overnight fast using multiple‐reaction monitoring‐based mass spectrometry. Twelve apolipoproteins were measured in 26 former term and 38 former very preterm infants. Key findings were confirmed by assessing apolipoprotein levels using antibody‐based assays. Comparing children born term and preterm, apolipoprotein A‐I, A‐IV, C‐II, and C‐III were significantly higher in the latter group. Term‐born children showed plasma levels of apolipoprotein C‐II and C‐III quantitatively similar to the adult range (Bruneck study). Hierarchical clustering analyses suggested that a higher proportion of apolipoprotein C‐III and C‐II reside on high‐density lipoprotein particles in children than in adults given the marked correlations of apolipoprotein C‐III and C‐II with high‐density lipoprotein cholesterol and apolipoprotein A‐I in children but not adults. High‐density lipoprotein cholesterol concentrations were similar in children and adults but the pattern of high‐density lipoprotein cholesterol–associated apolipoproteins was different (lower apolipoprotein A‐I and C‐I but higher A‐II, A‐IV, and M).

Conclusions

Our study defines apolipoprotein profiles in preschoolers and reports potential effects of prematurity. Further large‐scale studies are required to provide evidence whether this apolipoprotein signature of prematurity, including high apolipoprotein C‐II and C‐III levels, might translate into adverse cardiometabolic outcome in later life.

Prematurity-related knowledge among mothers and fathers of very preterm infants

OBJECTIVE

Empowering parents as health promoters may contribute to decrease the costs associated with prematurity. In Portugal, 8% and 1% of the births occurring in 2018 were preterm and very preterm, respectively. This study aimed to assess prematurity-related knowledge with regard to its prevalence, causes and consequences, according to sociodemographic, obstetric and offspring's characteristics, among mothers and fathers of very preterm infants.

METHODS

Between May and July 2017, mothers and fathers of very preterm infants were invited to participate through the Portuguese association of parents for support to the premature baby, with 196 parents being included. Knowledge on prematurity (prevalence, causes and consequences) was collected through a structured online questionnaire. Reporting of this research follows STROBE guidelines for cross-sectional studies.

RESULTS

Parents estimated a median prevalence of preterm and of very preterm delivery in Portugal of 15% and 8%, respectively. However, approximately 20% did not provide an estimate. More than 90% of the participants acknowledged placental complications, hypertensive disorders of pregnancy, multiple pregnancy and intrauterine growth restriction as causes of preterm delivery, whereas only 24.2% identified low socioeconomic status. Cardiac complications and respiratory morbidity were recognised as the main consequences of prematurity by more than 80% of the parents. Overall, parents with a higher socioeconomic status tended to provide correct responses more frequently than those with a low socioeconomic status.

CONCLUSIONS

The results revealed the existence of knowledge gaps regarding the prevalence, causes and consequences of premature delivery. Understanding the main facilitators and barriers to the achievement of prematurity-related knowledge may contribute for the global improvement of preventing this condition.

RELEVANCE TO CLINICAL PRACTICE

It is crucial to include the improvement of parents' knowledge about prematurity as a complementary dimension during the provision of medical care, with nurses playing a key role as main sources of information.

Maternal Work and Spontaneous Preterm Birth: A Multicenter Observational Study in Brazil

Spontaneous preterm birth (sPTB) is a major pregnancy complication involving biological, social, behavioural and environmental mechanisms. Workload, shift and intensity may play a role in the occurrence of sPTB. This analysis is aimed addressing the effect of occupational activities on the risk for sPTB and the related outcomes. We conducted a secondary analysis of the EMIP study, a Brazilian multicentre cross-sectional study. For this analysis, we included 1,280 singleton sPTB and 1,136 singleton term birth cases. Independent variables included sociodemographic characteristics, clinical complications, work characteristics, and physical effort devoted to household chores. A backward multiple logistic regression analysis was applied for a model using work characteristics, controlled by cluster sampling design. On bivariate analysis, discontinuing work during pregnancy and working until the 7^th month of pregnancy were risks for premature birth while working during the 8^th - 9^th month of pregnancy, prolonged standing during work and doing household chores appeared to be protective against sPTB during pregnancy. Previous preterm birth, polyhydramnios, vaginal bleeding, stopping work during pregnancy, or working until the 7^th month of pregnancy were risk factors in the multivariate analysis. The protective effect of variables compatible with exertion during paid work may represent a reverse causality. Nevertheless, a reduced risk associated with household duties, and working until the 8^th-9^th month of pregnancy support the hypothesis that some sort of physical exertion may provide actual protection against sPTB.

Simplified pulse wave velocity measurement in children: Is the pOpmètre valid?

In population exposed to cardiovascular risk, aortic stiffness is an important marker which is assessed by carotid-to-femoral pulse wave velocity (PWV). In childhood, the validated applanation tonometer SphygmoCor® can be used to measure PWV, but is limited in routine practice by the child's cooperation and operator's experience. An alternative device, the pOpmètre® is validated in adults and rapidly measures finger-to-toe PWV using 2 oxymeter-like sensors. The aim of this study is to validate the pOpmètre® device in children aged between 4 and 8 years. We compared simultaneous PWV measurements of the two devices, SphygmoCor® and pOpmètre®, in a training group, using the Bland-Altman method. Then we proposed an algorithm to correct pOpmètre® PWV (PWVpop). Finally, we validated this new algorithm in a validation group of children using the Bland-Altman method. This prospective study enrolled 26 children in the training group. Mean PWVpop was 3.919 ± 0.587 m/s and mean SphygmoCor® PWV was 4.280 ± 0.383 m/s, with a difference of -0.362(CI95%(-0.546;-0.178)) m/s. A new algorithm was defined using transit time (TTpop): corrected PWVpop (m/s) = 0.150/TTpop(s) + 1.381*Height(m) + 1.148. We enrolled 24 children in the validation group. Mean corrected PWVpop was 4.231 ± 0.189 m/s and mean SphygmoCor® PWV was 4.208 ± 0.296 m/s with a corrected difference of 0.023(CI95%(-0.086;0.131)) m/s. With this algorithm correction, we found an agreement between PWV measured by the SphygmoCor® and the pOpmètre®, with a difference of less than 10%. Using this algorithm, the pOpmètre® could be used in clinical or research practice in young children exposed to cardiovascular risk. (This study was registered as NCT02991703).

Updates on Assessment and Monitoring of the Postnatal Growth of Preterm Infants

Assessing and monitoring the physical growth of preterm infants is fundamental to NICU care. The goals of nutritional care are to approximate the growth and body composition of the healthy fetus and to support optimal brain development while minimizing future cardiometabolic risk. Both poor and excessive growth predict adverse long-term health outcomes. Growth curves are clinical tools used to assess the preterm infant's growth status. Several growth curves for preterm infants were developed in the past decade. To use them effectively, clinicians need to understand how each growth curve was developed; the underlying reference population; intended use; and strengths and limitations. Intrauterine growth curves are references that use size at birth to represent healthy fetal growth. These curves serve 2 purposes-to assign size classifications at birth and to monitor postnatal growth. The INTERGROWTH-21 ^st preterm postnatal growth standards were developed to compare the postnatal growth of preterm infants to that of healthy preterm infants rather than the fetus. Individualized weight growth curves account for the water weight loss that frequently occurs after birth. In addition, body mass index (BMI) curves are now available. In this review, we discuss the main characteristics of growth curves used for preterm infants as well as the use of percentiles, z scores, and their change over time to evaluate size and growth status. We also review the differences in body composition between preterm infants at term-equivalent age and term-born infants and the potential role of monitoring proportionality of growth using BMI curves.

No. 364-Antenatal Corticosteroid Therapy for Improving Neonatal Outcomes

OBJECTIVE

To assess the benefits and risks of antenatal corticosteroid therapy for women at risk of preterm birth or undergoing pre-labour Caesarean section at term and to make recommendations for improving neonatal and long-term outcomes.

OPTIONS

To administer or withhold antenatal corticosteroid therapy for women at high risk of preterm birth or women undergoing pre-labour Caesarean section at term.

OUTCOMES

Perinatal morbidity, including respiratory distress syndrome, intraventricular hemorrhage, bronchopulmonary dysplasia, infection, hypoglycemia, somatic and brain growth, and neurodevelopment; perinatal mortality; and maternal morbidity, including infection and adrenal suppression.

INTENDED USERS

Maternity care providers including midwives, family physicians, and obstetricians.

TARGET POPULATION

Pregnant women.

EVIDENCE

Medline, PubMed, Embase, and the Cochrane Library were searched from inception to September 2017. Medical Subject Heading (MeSH) terms and key words related to pregnancy, prematurity, corticosteroids, and perinatal and neonatal mortality and morbidity were used. Statements from professional organizations including that of the National Institutes of Health, the American College of Obstetricians and Gynecologists, the Society for Maternal Fetal Medicine, the Royal College of Obstetricians and Gynaecologists, and the Canadian Pediatric Society were reviewed for additional references. Randomized controlled trials conducted in pregnant women evaluating antenatal corticosteroid therapy and previous systematic reviews on the topic were eligible. Evidence from systematic reviews of non-experimental (cohort) studies was also eligible.

VALIDATION METHODS

This Committee Opinion has been reviewed and approved by the Maternal-Fetal Medicine Committee of the SOGC and approved by SOGC Council.

BENEFITS, HARMS, AND/OR COSTS

A course of antenatal corticosteroid therapy administered within 7 days of delivery significantly reduces perinatal morbidity/mortality associated with preterm birth between 24 + 0 and 34 + 6 weeks gestation. When antenatal corticosteroid therapy is given more than 7 days prior to delivery or after 34 + 6 weeks gestation, the adverse effects may outweigh the benefits. Evidence on long-term effects is scarce, and potential neurodevelopment harms are unquantified in cases of late preterm, term, and repeated exposure to antenatal corticosteroid therapy.

GUIDELINE UPDATE

Evidence will be reviewed 5 years after publication to evaluate the need for a complete or partial update of the guideline. If important evidence is published prior to the 5-year time point, an update will be issued to reflect new knowledge and recommendations.

SPONSORS

The guideline was developed with resources provided by the Society of Obstetricians and Gynaecologists of Canada with support from the Canadian Institutes of Health Research (APR-126338).

SUMMARY STATEMENTS

RECOMMENDATIONS: Gestational Age Considerations Agents, Dosage, Regimen, and Target Timing Subpopulations and Special Consideration.

Preterm Birth as a Risk Factor for Metabolic Syndrome and Cardiovascular Disease in Adult Life: A Systematic Review and Meta-Analysis

OBJECTIVE

To determine if preterm birth is associated with components of the metabolic syndrome in adult life.

STUDY DESIGN

A structured literature search was performed using PubMed. All comparative studies reported metabolic and cardiovascular outcomes in adults (≥18 years of age) born preterm (<37 weeks of gestation) compared with adults born at term (37-42 weeks of gestation) and published through March 2018 were included. The major outcomes assessed were body mass index, waist circumference, waist-to-hip ratio, fat mass, systolic blood pressure (SBP), diastolic blood pressure (DBP), 24-hour SBP, 24-hour DBP, endothelium-dependent brachial artery flow-mediated dilation, carotid intima-media thickness, pulse wave velocity, fasting glucose and insulin, Homeostasis Model Assessment-Estimated Insulin Resistance Index, and lipid profiles. Quality appraisal was performed using a modified version of the Newcastle-Ottawa scale. A meta-analysis was performed for comparable studies which reported sufficient data.

RESULTS

Forty-three studies were included, including a combined total of 18 295 preterm and 294 063 term-born adults. Prematurity was associated with significantly higher fat mass (P = .03), SBP (P < .0001), DBP (P < .0001), 24-hour SBP (P < .001), and 24-hour DBP (P < .001). Furthermore, preterm-born adults presented higher values of fasting glucose (P = .01), insulin (P = .002), Homeostasis Model Assessment-Estimated Insulin Resistance Index (P = .05), and total cholesterol levels (P = .05) in comparison with adults born at term, in random effect models. No statistically significant difference was found between preterm and term-born adults for the other outcomes studied.

CONCLUSIONS

Preterm birth is strongly associated with a number of components of the metabolic syndrome and cardiovascular disease in adult life.

Support during pregnancy for women at increased risk of low birthweight babies

BACKGROUND

Studies consistently show a relationship between social disadvantage and low birthweight. Many countries have programmes offering special assistance to women thought to be at risk for giving birth to a low birthweight infant. These programmes, collectively referred to in this review as additional social support, may include emotional support, which gives a person a feeling of being loved and cared for, tangible/instrumental support, in the form of direct assistance/home visits, and informational support, through the provision of advice, guidance and counselling. The programmes may be delivered by multidisciplinary teams of health professionals, specially trained lay workers, or a combination of lay and professional workers. This is an update of a review first published in 2003 and updated in 2010.

OBJECTIVES

The primary objective was to assess the effects of programmes offering additional social support (emotional, instrumental/tangible and informational) compared with routine care, for pregnant women believed to be at high risk for giving birth to babies that are either preterm (less than 37 weeks' gestation) or weigh less than 2500 g, or both, at birth. Secondary objectives were to determine whether the effectiveness of support was mediated by timing of onset (early versus later in pregnancy) or type of provider (healthcare professional or lay person).

SEARCH METHODS

For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) on 5 February 2018, and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised trials of additional social support during at-risk pregnancy by either a professional (social worker, midwife, or nurse) or specially trained lay person, compared to routine care. We defined additional social support as some form of emotional support (e.g. caring, empathy, trust), tangible/instrumental support (e.g. transportation to clinic appointments, home visits complemented with phone calls, help with household responsibilities) or informational support (advice and counselling about nutrition, rest, stress management, use of alcohol/recreational drugs).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion and risk of bias, extracted data and checked them for accuracy. We assessed the quality of the evidence using the GRADE approach.

MAIN RESULTS

This updated review includes a total of 25 studies, with outcome data for 11,246 mothers and babies enrolled in 21 studies. We assessed the overall risk of bias of included studies to be low or unclear, mainly because of limited reporting or uncertainty in how randomisation was generated or concealed (which led us to downgrade the quality of most outcomes to moderate), and the impracticability of blinding participants.When compared with routine care, programmes offering additional social support for at-risk pregnant women may slightly reduce the number of babies born with a birthweight less than 2500 g from 127 per 1000 to 120 per 1000 (risk ratio (RR) 0.94, 95% confidence interval (CI) 0.86 to 1.04; 16 studies, n = 11,770; moderate-quality evidence), and the number of babies born with a gestational age less than 37 weeks at birth from 128 per 1000 to 117 per 1000 (RR 0.92, 95% CI 0.84 to 1.01, 14 studies, n = 12,282; moderate-quality evidence), though the confidence intervals for the pooled effect for both of these outcomes just crossed the line of no effect, suggesting any effect is not large. There may be little or no difference between interventions for stillbirth/neonatal death (RR 1.11, 95% CI 0.88 to 1.41; 15 studies, n = 12,091; low-quality evidence). Secondary outcomes of moderate quality suggested that there is probably a reduction in caesarean section (from 215 per 1000 to 194 per 1000; RR 0.90, 95% CI 0.83 to 0.97; 15 studies, n = 9550), a reduction in the number of antenatal hospital admissions per participant (RR 0.78, 95% CI 0.68 to 0.91; 4 studies; n = 787), and a reduction in the mean number of hospitalisation episodes (mean difference -0.05, 95% CI -0.06 to -0.04; 1 study, n = 1525) in the social support group, compared to the controls.Postnatal depression and women's satisfaction were reported in different ways in the studies that considered these outcomes and so we could not include data in a meta-analysis. In one study postnatal depression appeared to be slightly lower in the support group in women who screened positively on the Edinbugh Postnatal Depression Scale at eight to 12 weeks postnatally (RR 0.74, 95% CI 0.55 to 1.01; 1 study, n = 1008; moderate-quality evidence). In another study, again postnatal depression appeared to be slightly lower in the support group and this was a self-report measure assessed at six weeks postnatally (RR 0.85, 95% CI 0.69 to 1.05; 1 study, n = 458; low-quality evidence). A higher proportion of women in one study reported that their prenatal care was very helpful in the supported group (RR 1.17, 95% CI 1.05 to 1.30; 1 study, n = 223; moderate-quality evidence), although in another study results were similar. Another study assessed satisfaction with prenatal care as being "not good" in 51 of 945 in the additional support group, compared with 45 of 942 in the usual care group.No studies considered long-term morbidity for the infant. No single outcome was reported in all studies. Subgroup analysis demonstrated consistency of effect when the support was provided by a healthcare professional or a trained lay worker.The descriptions of the additional social support were generally consistent across all studies and included emotional support, tangible support such as home visits, and informational support.

AUTHORS' CONCLUSIONS

Pregnant women need the support of caring family members, friends, and health professionals. While programmes that offer additional social support during pregnancy are unlikely to have a large impact on the proportion of low birthweight babies or birth before 37 weeks' gestation and no impact on stillbirth or neonatal death, they may be helpful in reducing the likelihood of caesarean birth and antenatal hospital admission.

Paediatrician's guide to epigenetics

Epigenetic regulation of gene expression is critical for normal development. Dysregulation of the epigenome can lead to the development and progression of a number of diseases relevant to paediatricians, including disorders of genomic imprinting and malignancies. It has long been recognised that early life events have implications for future disease risk, and epigenetic modifications may play a role in this, although further high-quality research is needed to better understand the underlying mechanisms. Research in the field of epigenetics will contribute to a greater understanding of growth, development and disease; however, paediatricians need to be able to interpret such research critically, in order to use the potential advances brought about through epigenetic studies while appreciating their limitations.

Developmental origins of myocardial abnormalities in postnatal life 1

Poor quality and quantity maternal nutrition during pregnancy exerts permanent and damaging effects on the heart of the developing fetus. The developmental origin of adult heart disease is considered an important and critical factor in the pathogenesis of myocardial abnormalities in later life. Low birth mass, a marker of intrauterine stress, has been linked to a predisposition to heart disease. In this article, our work on the impact of exposure to a low-protein diet, in utero, on the developing heart and its long-term consequences are discussed. Other studies providing some supportive evidence are also described. It is proposed that normal fetal nutrition, growth, and development through efficient maternal nutrition (as well as other predisposing factors) before and during pregnancy may serve as a strategy for the primary prevention of heart disease.

Small-Scale Variations in Urban Air Pollution Levels Are Significantly Associated with Premature Births: A Case Study in São Paulo, Brazil

Premature birth is the result of a complex interaction among genetic, epigenetic, behavioral, socioeconomic, and environmental factors. We evaluated the possible associations between air pollution and the incidence of prematurity in spatial clusters of high and low prevalence in the municipality of São Paulo. It is a spatial case-control study. The residential addresses of mothers with live births that occurred in 2012 and 2013 were geo-coded. A spatial scan statistical test performed to identify possible low-prevalence and high-prevalence clusters of premature births. After identifying, the spatial clusters were drawn samples of cases and controls in each cluster. Mothers were interviewed face-to-face using questionnaires. Air pollution exposure was assessed by passive tubes (NO₂ and O₃) as well as by the determination of trace elements' concentration in tree bark. Binary logistic regression models were applied to determine the significance of the risk of premature birth. Later prenatal care, urinary infection, and hypertension were individual risk factors for prematurity. Particles produced by traffic emissions (estimated by tree bark accumulation) and photochemical pollutants involved in the photochemical cycle (estimated by O₃ and NO₂ passive tubes) also exhibited significant and robust risks for premature births. The results indicate that air pollution is an independent risk factor for prematurity.

N° 364 - La Corticothérapie Prénatale Pour Améliorer Les Issues Néonatales

OBJECTIF

Évaluer les avantages et les risques de la corticothérapie prénatale chez les femmes qui présentent un risque d'accouchement prématuré ou qui subissent une césarienne à terme avant début de travail, et formuler des recommandations visant l'amélioration des issues néonatales et des issues à long terme.

OPTIONS

Administrer ou ne pas administrer une corticothérapie prénatale aux femmes qui présentent un risque élevé d'accouchement prématuré ou qui subissent une césarienne avant travail à terme. RéSULTATS: Morbidité périnatale, notamment le syndrome de détresse respiratoire, l'hémorragie intraventriculaire, la dysplasie bronchopulmonaire, l'infection, l'hypoglycémie, ainsi que les troubles de la croissance somatique et cérébrale et du neurodéveloppement; mortalité périnatale; et morbidité maternelle, notamment l'infection et la suppression surrénalienne.

UTILISATEURS CIBLES

Fournisseurs de soins de maternité, notamment les sages-femmes, les médecins de famille et les obstétriciens.

POPULATION CIBLE

Femmes enceintes. ÉVIDENCE: Nous avons interrogé les bases de données Medline, PubMed et Embase ainsi que la Bibliothèque Cochrane, de leur création au mois de septembre 2017. Nous nous sommes servis de Medical Subjet Headings (MeSH) et de mots clés en lien avec la grossesse, la prématurité, les corticostéroïdes ainsi que la mortalité et la morbidité périnatales et néonatales. Nous avons également consulté les déclarations d'organismes professionnels tels que les National Institutes of Health, l'American College of Obstetricians and Gynecologists, la Society for Maternal-Fetal Medicine, le Royal College of Obstetricians and Gynaecologists et la Société canadienne de pédiatrie pour obtenir des références additionnelles. Les essais cliniques randomisés évaluant la corticothérapie prénatale menés sur des femmes enceintes et les revues systématiques antérieures sur le sujet étaient admissibles, tout comme les données venant de revues systématiques d'études non expérimentales (études de cohorte).

VALEURS

La présente opinion de comité a été révisée et approuvée par le Comité de médecine fœto-maternelle de la SOGC, et approuvée par le Conseil de la SOGC. AVANTAGES, INCONVéNIENTS ET COûTS: L'administration d'une corticothérapie prénatale dans les sept jours précédant l'accouchement réduit significativement la morbidité et la mortalité périnatales associées à la naissance prématurée survenant entre 24+0 et 34+6 semaines de grossesse. Si la corticothérapie prénatale est administrée plus de sept jours avant l'accouchement ou après 34+6 semaines de grossesse, les effets indésirables peuvent surpasser les avantages. Les données probantes sur l'impact à long terme de la corticothérapie prénatale sont rares. Par ailleurs, les effets neurodéveloppementaux néfastes potentiels de l'exposition répétée à la corticothérapie prénatale ou de l'administration de corticostéroïdes en période préterme tardive ou à terme n'ont pas été quantifiés. MIS-à-JOUR à LA DIRECTIVE: Une revue des données probantes sera menée cinq ans après la publication de la présente directive clinique afin d'évaluer si une mise à jour complète ou partielle s'impose. Si de nouvelles données probantes importantes sont publiées avant la fin de ces cinq ans, une mise à jour tenant compte des nouvelles connaissances et recommandations sera publiée.

COMMANDITAIRES

La présente directive clinique a été élaborée à l'aide de ressources fournies par la Société des obstétriciens et gynécologues du Canada et avec l'appui des Instituts de recherche en santé du Canada (APR-126338). MOTS CLéS: Corticothérapie prénatale, maturation fœtale, prématurité, période préterme tardive, césarienne avant travail DÉCLARATION SOMMAIRES: RECOMMANDATIONS: Considérations relatives à l'âge gestationnel.

Macronutrient and fibre intake of young Spanish children with reference to their in utero growth status: Are they eating a healthy diet?

AIM

To compare macronutrient and fibre intake by pre-school children born with intra-uterine growth restriction (IUGR) or as appropriate for gestational age (AGA) and to compare their intake with paediatric nutritional recommendations for identification of potential areas of modification during early life.

METHODS

A parental 3-day dietary record was obtained for children of age 1-6 years, born at Hospital Clinic, Barcelona, Spain (2002-2007) with IUGR (n = 37) or AGA (n = 53). Mean nutrient intake (adjusted for body mass index), nutrient adequacy ratios (NAR) and percentage of energy intake (EI%) were compared.

RESULTS

Macronutrient and fibre intake of the two groups did not differ significantly. However, IUGR children showed significantly higher than the recommended levels of protein EI% (18 (95% confidence interval (CI) 16-19)), NAR for saturated fatty acids (SFAs) (1.2 (95% CI 1.1-1.5)) and NAR for carbohydrate (1.4 (95% CI 1.2-1.6)) and significantly lower than the recommended levels of NAR for unsaturated fatty acids (UFAs) (0.6 (95% CI 0.5-0.8)) and for fibre (0.6 (95% CI 0.5-0.8)). Likewise, children born with AGA showed similar pattern compared to the recommended levels for protein EI% (17 (95% CI 16-18)), NAR for SFAs (1.3 (95% CI 1.2-1.4)), NAR for UFAs (0.6 (95% CI 0.5-0.7)) and NAR for fibre (0.8 (95% CI 0.7-0.9)).

CONCLUSION

Spanish pre-school children consume proteins and SFAs in abundance and UFAs and fibre in moderation. Reinforcement of healthy eating is recommended for long-term health benefits, especially for at-risk children born with IUGR, whose consumption of carbohydrate is additionally greater than that recommended.

Pediatric Cardiovascular Morbidity of the Early Term Newborn

OBJECTIVE

To determine whether early term delivery (at 37^0/7-38^6/7 weeks of gestation) is associated with long-term pediatric cardiovascular morbidity of the offspring.

STUDY DESIGN

A population-based cohort analysis was performed including all term deliveries occurring between 1991 and 2014 at a single tertiary medical center. Gestational age at delivery was subdivided into early term (37^0/7-38^6/7), full term (39^0/7-40^6/7), late term (41^0/7-41^6/7) and post term (≥42^0/7) delivery. Hospitalizations of children up to the age of 18 years involving cardiovascular morbidity were evaluated, including structural valvular disease, hypertension, arrhythmias, rheumatic fever, ischemic heart disease, pulmonary heart disease, perimyoendocarditis, congestive heart failure, and others. Kaplan-Meier survival curves were used to compare cumulative hospitalization incidence between groups. A multivariable Weibull parametric model was used to control for confounders.

RESULTS

During the study period, 223 242 term singleton deliveries met the inclusion criteria. Of them, 24% (n = 53 501) occurred at early term. Hospitalizations involving cardiovascular morbidity were significantly more common in children delivered at early term (0.7%) as compared with those born at full (0.6%), late (0.6%), or post term (0.5%; P = .01). The survival curve demonstrated a significantly higher cumulative incidence of cardiovascular-related hospitalizations in the early term group (log-rank P <.001). In the Weibull model, early term delivery was found to be an independent risk factor for cardiovascular-related hospitalization as compared with full term delivery (adjusted HR, 1.16; 95% CI, 1.01-1.32; P = .02).

CONCLUSION

Early term delivery is independently associated with pediatric cardiovascular morbidity of the offspring as compared with offspring born at full term.

Alterations in glucose concentrations affect DNA methylation at Lrg1 in an ex vivo rat cortical slice model of preterm brain injury

Preterm birth affects 5-18% of all babies and is associated with neurodevelopmental impairment and increased neuropsychiatric disease risk. Although preterm birth associates with differential DNA methylation at neurodevelopmental genes in buccal DNA, including leucine-rich alpha-2-glycoprotein 1 (LRG1), it is not known whether these differences also occur in the brain, or whether they persist. Thus, there is a need for animal models or in vitro systems in which to undertake longitudinal and mechanistic studies. We used a combination of in vivo rat studies and ex vivo experiments in rat cortical slices to explore their utility in modelling the human preterm brain. We identified temporal changes in DNA methylation at LRG1 in human buccal DNA over the first year of life and found persistent differences in LRG1 methylation between preterm and term infants at 1 year. These developmental changes also occurred in rat brains in vivo, alongside changes in global DNA hydroxymethylation and expression of the ten-eleven translocation (Tet1) enzyme, and were reproducible in ex vivo rat cortical slices. On the basis of the observation that neonatal glucose homeostasis can modify neurodevelopmental outcome, we studied whether glucose concentration affects Lrg1 methylation using cortical slices. Culture of slices in lower glucose concentration was associated with lower Lrg1 methylation, lower global 5hmC and Tet1 expression. Our results suggest that ex vivo organotypic cultures may be useful in the study of biological and environmental influences on the epigenome and that perturbations during early life including glucose concentration can affect methylation at specific genes implicated in neurodevelopment.

Preterm birth and the timing of puberty: a systematic review

BACKGROUND

An estimated 11% of births occur preterm, and survival is improving. Early studies suggested an association between preterm birth and earlier puberty. Given the adverse outcomes associated with early puberty this could have significant public health implications. The objective of this review was to assess the timing of puberty after preterm birth.

METHODS

Pubmed, Embase, Popline, Global Health and Global Health Library were searched using terms relating to "premature birth", "menarche", "puberty" and "follow up studies". Inclusion criteria were a population consisting of pubertal or post-pubertal adolescents and adults; studies which defined preterm delivery in participants and compared outcomes to those after term delivery; and a quantitative assessment of pubertal onset. Assessment of risk of bias was conducted using principles from the Critical Appraisal Study Process.

RESULTS

Our search identified 1051 studies, of which 16 met the inclusion criteria. In females, 8 studies found no association between preterm birth and the timing of menarche. Five studies found earlier onset in preterm infants, 1 found later onset, and 1 showed both earlier and later menarche, depending on birth weight. The range of effect of studies showing earlier menarche was - 0.94 to -0.07 years in the preterm group, with a median of - 0.3 years. In males, 2 studies showed earlier onset of puberty in the preterm group, 5 showed no difference, and 1 showed later onset. Most studies did not present outcomes in the form of a mean with standard deviation, precluding a meta-analysis. There was insufficient data to address potential confounding factors.

CONCLUSIONS

The published evidence does not suggest that being born preterm leads to a significant acceleration in the onset of puberty. This should prove reassuring for public health purposes, and for clinicians counseling parents of infants born preterm.

A systematic review of concepts related to women's empowerment in the perinatal period and their associations with perinatal depressive symptoms and premature birth

Background

The perinatal period, which we here define as pregnancy and the first year postpartum, is a time in women’s lives that involves significant physiological and psychosocial change and adjustment, including changes in their social status and decision-making power. Supporting women’s empowerment at this particular time in their lives may be an attractive opportunity to create benefits for maternal and infant health outcomes such as reductions in perinatal depressive symptoms and premature birth rates. Thus, we here systematically review and critically discuss the literature that investigates the effects of empowerment, empowerment-related concepts and empowerment interventions on reductions in perinatal depressive symptoms, preterm birth (PTB), and low birthweight (LBW).

Methods

For this systematic review, we conducted a literature search in PsychInfo, PubMed, and CINAHL without setting limits for date of publication, language, study design, or maternal age. The search resulted in 27 articles reporting on 25 independent studies including a total of 17,795 women.

Results

The majority of studies found that, for the most part, measures of empowerment and interventions supporting empowerment are associated with reduced perinatal depressive symptoms and PTB/LBW rates. However, findings are equivocal and a small portion of studies found no significant association between empowerment-related concepts and perinatal depressive symptoms and PTB or LBW.

Conclusion

This small body of work suggests, for the most part, that empowerment-related concepts may be protective for perinatal depressive symptoms and PTB/LBW. We recommend that future theory-driven and integrative work should include an assessment of different facets of empowerment, obtain direct measures of empowerment, and address the relevance of important confounders, including for example, ethnicity and socioeconomic status.

Electronic supplementary material

The online version of this article (doi:10.1186/s12884-017-1495-1) contains supplementary material, which is available to authorized users.

Growth attainment in German children born preterm, and cardiovascular risk factors in adolescence. Analysis of the population representative KiGGS data

AIM

To compare the growth attainment of preterm children and their cardiovascular risk factors at adolescence with the values measured in term children in Germany.

METHODS

About 17,641 children aged 0 to <18 years were studied between 2003 and 2006 in the population representative German KiGGS survey ("German Health Interview and Examination Survey for Children and Adolescents") using questionnaires, physical examinations, standardized anthropometric and blood pressure measurements, and blood sample analyses. Analysis of covariance (ANCOVA) was employed for the analyses of anthropometric parameters.

RESULTS

About 11.8% of the 16,737 children with complete and valid data had been born preterm. After adjustment for covariates the estimated z-scores over the total age range were larger in term compared to preterm children for length/height (P<0.001; estimated difference B=0.277, 95% CI 0.191-0.362), head circumference (P<0.001; B=0.238, 95% CI 0.144-0.333), BMI (P=0.001; B=0.160, 95% CI 0.069-0.252), and skinfold thickness (P=0.220; B=0.058, 95% CI -0.035 to 0.151). The onset of pubertal development was slightly (but not significantly) earlier in term compared to preterm children. At 14 to <18 years, anthropometric and biochemical indicators of cardiovascular diseases were not worse in preterm compared to term children.

CONCLUSIONS

Preterm-born German adolescents remained significantly shorter, lighter, and had a smaller head circumference than term-born adolescents, but the risk indicators for cardiovascular diseases were not higher.

Former very preterm infants show alterations in plasma amino acid profiles at a preschool age

BACKGROUND

Amino acid analysis is a valuable tool for cardiovascular risk assessment. Preterm infants display plasma amino acid changes in the newborn period. Whether these changes persist is unknown to date. The aim of this study was to assess whether former very preterm infants (VPI) show alterations in amino acid patterns indicative of an unfavorable cardiovascular risk profile at a preschool age.

METHODS

From 5-7 y-old children born at term or <32 wk gestation (VPI) were included in the study. Plasma amino acid concentrations were determined after an overnight fast.

RESULTS

29 former term infants and 79 former VPI were included in the study. Former VPI showed changes in various plasma amino acids including glutamine, arginine, citrulline, tryptophan, glutamate, ornithine, and taurine. Branched-chain amino acids were lower, alanine/lysine ratios significantly higher in the preterm population.

CONCLUSION

Former VPI show altered plasma amino acid profiles indicative of a dualistic cardiovascular risk profile (e.g., potentially beneficial elevations in citrulline, arginine, glutamine, and tryptophan, but also raised alanine/lysine ratios, low ornithine and taurine levels) at a preschool age. Whether this is associated with an adverse cardiovascular outcome has to be addressed by future studies. Long-term cardiometabolic follow-up of VPI might be warranted.

Pregnancy and kidney disease: from medicine based on exceptions to exceptional medicine

The Webster dictionary defines exception as an anomaly, a person or thing that does not follow a rule, while the adjective exceptional has a different nuance, and means "above average". These two words may describe how obstetric nephrology has shifted from the description of very rare cases, to the development of a complex new and fascinating branch of medicine, that counterbalances obstetricians' usually optimistic outlook by focusing on subtle challenges posed by chronic diseases, and mitigate the frequently grim approach of nephrologists, with a message of hope: women with kidney disease can have the same basic life goals as healthy women their age. Although studies relating to kidney disease in pregnancy are being published more frequently, not all questions have been considered or answered, and clinicians are often challenged by a lack of detailed information and practical guidelines. Thus in this complex, difficult, but also fascinating and evolving panorama, the Journal of Nephrology is publishing a issue dedicated to obstetric nephrology, in an attempt to contribute to the development of this field, with the specific aim of offering practical insights and critical contributions capable of helping clinicians in the management of these "exceptional exceptions".

Post-term growth and cognitive development at 5 years of age in preterm children: Evidence from a prospective population-based cohort

While the effects of growth from birth to expected term on the subsequent development of preterm children has attracted plentiful attention, less is known about the effects of post-term growth. We aimed to delineate distinct patterns of post-term growth and to determine their association with the cognitive development of preterm children. Data from a prospective population-based cohort of 3,850 surviving infants born at less than 35 weeks of gestational age were used. Growth was assessed as the Body Mass Index (BMI) Z-scores at 3, 9, 18, 24, 36, 48, and 60 months. Cognitive development at five years of age was evaluated by the Global School Adaptation score (GSA). Latent class analysis was implemented to identify distinct growth patterns and logistic regressions based on propensity matching were used to evaluate the relationship between identified growth trajectories and cognitive development. Four patterns of post-term growth were identified: a normal group with a Z-score consistently around zero during childhood (n = 2,469; 64%); a group with an early rapid rise in the BMI Z-score, but only up to 2 years of age (n = 195; 5%); a group with a slow yet steady rise in the BMI Z-score during childhood (n = 510; 13%); and a group with a negative Z-score growth until 3 years of age (n = 676; 18%). The group with a slow yet steady rise in the BMI Z-score was significantly associated with low GSA scores. Our findings indicate heterogeneous post-term growth of preterm children, with potential for association with their cognitive development.

Renal consequences of preterm birth

Background

The developmental origin of health and disease concept identifies the brain, cardiovascular, liver, and kidney systems as targets of fetal adverse programming with adult consequences. As the limits of viability in premature infants have been pushed to lower gestational ages, the long-term impact of prematurity on kidneys still remains a significant burden during hospital stay and beyond.

Objectives

The purpose of this study is to summarize available evidence, mechanisms, and short- and long-term renal consequences of prematurity and identify nephroprotective strategies and areas of uncertainty.

Results

Kidney size and nephron number are known to be reduced in surviving premature infants due to disruption of organogenesis at a crucial developmental time point. Inflammation, hyperoxia, and antiangiogenic factors play a role in epigenetic conditioning with potential life-long consequences. Additional kidney injury from hypoperfusion and nephrotoxicity results in structural and functional changes over time which are often unnoticed. Nephropathy of prematurity and acute kidney injury confound glomerular and tubular maturation of preterm kidneys. Kidney protective strategies may ameliorate growth failure and suboptimal neurodevelopmental outcomes in the short term. In later life, subclinical chronic renal disease may progress, even in asymptomatic survivors.

Conclusion

Awareness of renal implications of therapeutic interventions and renal conservation efforts may lead to a variety of short and long-term benefits. Adequate monitoring and supplementation of microelement losses, gathering improved data on renal handling, and exploration of new avenues such as reliable markers of injury and new therapeutic strategies in contemporary populations, as well as long-term follow-up of renal function, is warranted.

Former Very Preterm Infants Show an Unfavorable Cardiovascular Risk Profile at a Preschool Age

Cardiovascular disease is the leading cause of death worldwide. Evidence points towards an unfavorable cardiovascular risk profile of former preterm infants in adolescence and adulthood. The aim of this study was to determine whether cardiovascular risk predictors are detectable in former very preterm infants at a preschool age. Five- to seven-year-old children born at <32 weeks’ gestational age were included in the study. Same-aged children born at term served as controls. Basic data of study participants were collected by means of follow-up databases and standardized questionnaires. At study visit, anthropometric data, blood pressure readings and aortic intima-media thickness were assessed. Blood samples were obtained after an overnight fast. In comparison to children born at term, former preterm infants had higher systolic and diastolic blood pressure readings (odds ratio [95% confidence interval] per 1-SD higher blood pressure level 3.2 [2.0–5.0], p<0.001 and 1.6 [1.1–1.2], p = 0.008), fasting glucose levels (OR [95% CI] 5.2 [2.7–10.1], p<0.001), homeostasis model assessment index (OR [95% CI] 1.6 [1.0–2.6], p = 0.036), and cholesterol levels (OR [95% CI] 2.1 [1.3–3.4], p = 0.002). Systolic prehypertension (23.7% vs. 2.2%; OR [95% CI] 13.8 [3.1–60.9], p = 0.001), elevated glucose levels (28.6% vs. 5.9%; OR [95% CI] 6.4 [1.4–28.8], p = 0.016), and hypercholesterolemia (77.4% vs. 52.9%; OR [95% CI] 3.0 [1.3–7.1], p = 0.010) were significantly more prevalent in the preterm group. As former very preterm infants display an unfavorable cardiovascular risk profile already at a preschool age, implementation of routine cardiovascular follow-up programs might be warranted.

Possible relationship between common genetic variation and white matter development in a pilot study of preterm infants

BACKGROUND

The consequences of preterm birth are a major public health concern with high rates of ensuing multisystem morbidity, and uncertain biological mechanisms. Common genetic variation may mediate vulnerability to the insult of prematurity and provide opportunities to predict and modify risk.

OBJECTIVE

To gain novel biological and therapeutic insights from the integrated analysis of magnetic resonance imaging and genetic data, informed by prior knowledge.

METHODS

We apply our previously validated pathway-based statistical method and a novel network-based method to discover sources of common genetic variation associated with imaging features indicative of structural brain damage.

RESULTS

Lipid pathways were highly ranked by Pathways Sparse Reduced Rank Regression in a model examining the effect of prematurity, and PPAR (peroxisome proliferator-activated receptor) signaling was the highest ranked pathway once degree of prematurity was accounted for. Within the PPAR pathway, five genes were found by Graph Guided Group Lasso to be highly associated with the phenotype: aquaporin 7 (AQP7), malic enzyme 1, NADP(+)-dependent, cytosolic (ME1), perilipin 1 (PLIN1), solute carrier family 27 (fatty acid transporter), member 1 (SLC27A1), and acetyl-CoA acyltransferase 1 (ACAA1). Expression of four of these (ACAA1, AQP7, ME1, and SLC27A1) is controlled by a common transcription factor, early growth response 4 (EGR-4).

CONCLUSIONS

This suggests an important role for lipid pathways in influencing development of white matter in preterm infants, and in particular a significant role for interindividual genetic variation in PPAR signaling.

The Impact of Parental Personality on Birth Outcomes: A Prospective Cohort Study

Objective

To investigate the effect of parental personality on birth outcomes.

Design

Prospective cohort study.

Setting

727 pregnant women and 579 spouses receiving antenatal care at a single-center in rural Tokyo, Japan during 2010–2013.

Methods

We measured the association between maternal effect of parental personality traits assessed by the Cloninger’s Temperament and Character Inventory on birth outcomes, using multiple regression and adjusting for demographics.

Results

Maternal self-transcendence personality was inversely associated with gestational age [-0.26 (95% confidence interval (CI): -0.51 to -0.01) weeks per unit] and positively associated with preterm birth [odds ratio (OR) 2.60 (95% CI: 1.00 to 6.75) per unit], while paternal self-transcendence personality was positively associated with gestational age [0.31 (95% CI: 0.07 to 0.55) weeks per unit]. Maternal reward dependence was positively associated with fetal growth [0.30 (95% CI: 0.02 to 0.59) per unit]. Other maternal and paternal personality traits associated with adverse maternal behavior, such as novelty seeking, harm avoidance and self-directedness, were not associated with birth outcomes.

Conclusion

We found that specific parental personality traits can be associated with birth outcomes.

Dynamic Changes in DNA Methylation Occur during the First Year of Life in Preterm Infants

BACKGROUND

Preterm birth associates with a substantially increased risk of later cardiovascular disease and neurodevelopmental disorders. Understanding underlying mechanisms will facilitate the development of screening and intervention strategies to reduce disease risk. Changes in DNA methylation have been proposed as one mechanism linking the early environment with later disease risk. We tested the hypothesis that preterm birth associates with altered DNA methylation in genes encoding insulin-like growth factor 2 (IGF2) and FK506-binding protein 5 (FKBP5), which appear particularly vulnerable to early life adversity.

METHODS

Fifty preterm infants were seen and assessed at birth, term equivalent age, 3 months and 1-year corrected ages; 40 term infants were seen at birth, 3 months and 1 year. Saliva was collected for DNA extraction at birth, term, and 1 year. Pyrosequencing of bisulfite-converted DNA was performed to measure DNA methylation at specific CpG sites within the IGF2 and FKBP5 loci.

RESULTS

Weight and head circumference was reduced in preterm infants at all time points. Preterm infants had a higher percentage body fat at term-corrected age, but this difference was not persistent. DNA methylation at the differentially methylated region (DMR) of IGF2 (IGF2DMR2) and FKBP5 was lower in preterm infants at birth- and term-corrected age compared to term infants at birth. IGF2DMR2 and FKBP5 methylation was related to birthweight SD score in preterm infants. Among preterm infants, social deprivation was an independent contributor toward reducing DNA methylation at IGF2DMR2 at birth- and term-corrected age and maternal smoking was associated with reduced DNA methylation at FKBP5 at birth. There were no persistent differences in DNA methylation at 1 year of age.

CONCLUSION

Changes in DNA methylation were identified at key regions of IGF2/H19 and FKBP5 in preterm infants in early life. Potential contributing factors include maternal smoking and social deprivation. However, these changes did not persist at 1 year of age and further longitudinal studies are required to determine any associations between altered DNA methylation in the perinatal period of individuals born preterm and their long-term health.

Rate of establishing the gut microbiota in infancy has consequences for future health

The gut of the human neonate is colonized rapidly after birth from an early sparse and highly distinct microbiota to a more adult-like and convergent state, within 1 to 3 years. The progression of colonizing bacterial species is non-random. During the first months of life several shifts commonly occur in the species prevalent in our guts. Although the sequential progression of these species is remarkably consistent across individuals and geographies, there is inter-individual variation in the rate of progression. Our study and others suggest that the rate is influenced by environmental factors, and influences our future health. In this article, we review our recent contribution to cataloging the developing infant gut microbiota alongside other important recent studies. We suggest testable hypotheses that arise from this synthesis.

Developmental Programming: Priming Disease Susceptibility for Subsequent Generations

Racial and/or ethnic minorities carry the highest burden of many adverse health outcomes intergenerationally We propose a paradigm in which developmental programming exacerbates the effects of racial patterning of adverse environmental conditions, thereby contributing to health disparity persistence. Evidence that developmental programming induces a heightened response to adverse exposures ("second hits") encountered later in life is considered. We evaluated the evidence for the second hit phenomenon reported in animal and human studies from three domains (air, stress, nutrition). Original research including a gestational exposure and a childhood or adulthood second hit exposure was reviewed. Evidence from animal studies suggest that prenatal exposure to air pollutants is associated with an exaggerated reaction to postnatal air pollution exposure, which results in worse health outcomes. It also indicates offspring exposed to prenatal maternal stress produce an exaggerated response to subsequent stressors, including anxiety and hyper-responsiveness of the hypothalamic-pituitary-adrenal axis. Similarly, prenatal and postnatal Western-style diets induce synergistic effects on weight gain, metabolic dysfunction, and atherosclerotic risk. Cross-domain second hits (e.g., gestational air pollution followed by childhood stressor) were also considered. Suboptimal gestational environments induce exaggerated offspring responses to subsequent environmental and social exposures. These developmental programming effects may result in enhanced sensitivity of ongoing, racially patterned, adverse exposures in race/ethnic minorities, thereby exacerbating health disparities from one generation to the next. Empirical assessment of the hypothesized role of priming processes in the propagation of health disparities is needed. Future social epidemiology research must explicitly consider synergistic relationships among social environmental conditions to which gestating females are exposed and offspring exposures when assessing causes for persistent health disparities.

Behavior change, health, and health disparities: an introduction

This Special Issue of Preventive Medicine (PM) focuses on behavior change, health, and health disparities, topics of fundamental importance to improving population health in the U.S. and other industrialized countries. While the U.S. health care system and those of other industrialized countries were developed to manage infectious disease and acute illnesses, it is chronic health conditions that most need to be understood and managed in the 21st century. The evidence is clear that personal behavior patterns like cigarette smoking and physical inactivity/obesity are critically important proximal causes of chronic disease (cardiovascular disease, site-specific cancers, type-2 diabetes) and as such behavior change will need to be a key component of their management. As the outstanding contributions to this Special Issue illustrate, substantial headway is being made in advancing knowledge including developing effective prevention and treatment strategies, with cigarette smoking being an excellent example that change is possible. That said, cigarette smoking continues to be responsible for approximately 480,000 premature deaths annually in the U.S. alone and 5 million globally. So more needs to be done, especially in economically disadvantaged populations. The same certainly applies to the challenges of the obesity epidemic, which of course is a more recent problem and understandably efforts to curtail it are in earlier stages of development.